Note: Descriptions are shown in the official language in which they were submitted.
CA 03116921 2021-04-16
WO 2020/096860 PCT/US2019/059196
COOPERATIVE MULTIPLE-INPUT MULTIPLE-OUTPUT DOWNLINK
SCHEDULING
CROSS REFERENCE TO PRIORITY APPLICATIONS
[0001] This application claims the benefit of priority of U.S. Patent
Application
No. 16/180,848, filed November 5, 2018 and titled "COOPERATIVE MULTIPLE-INPUT
MULTIPLE-OUTPUT DOWNLINK SCHEDULING;" U.S. Patent Application
No. 16/180,799, filed November 5, 2018 and titled "VARIABLE MULTIPLE-INPUT
MULTIPLE-OUTPUT DONWLINK USER EQUIPMENT," issued as U.S. Patent
No. 10,432,272 on October 1, 2019; U.S. Patent Application No. 16/180,869,
filed
November 5, 2018 and titled "USER EQUIPMENT ASSISTED MULTIPLE-INPUT
MULTIPLE-OUTPUT DOWNLINK CONFIGURATION; " and U.S. Patent Application
No. 16/180,947, filed November 5, 2018 and titled "DISTRIBUTED MULTIPLE-INPUT
MULTIPLE-OUTPUT DOWNLINK CONFIGURATION." The disclosures of each of the
above-mentioned applications are hereby incorporated by reference herein in
their entireties
and for all purposes.
BACKGROUND
Technical Field
[0002] Embodiments of this disclosure relate to wireless communication
systems
such as heterogeneous multiple-input multiple output wireless communication
systems.
Description of Related Technology
[0003] The types of modern computing devices continues to increase
along with
the differing and dynamic needs of each device. The wireless communication
systems
providing services to such devices are facing increasing constraints on
resources and
demands for quality and quantities of service. Accordingly, improvements in
providing
wireless communication services, such as in a multiple-input multiple-output
system, are
desired.
1
CA 03116921 2021-04-16
WO 2020/096860 PCT/US2019/059196
SUMMARY OF CERTAIN INVENTIVE ASPECTS
[0004] The innovations described in the claims each have several
aspects, no
single one of which is solely responsible for its desirable attributes.
Without limiting the
scope of the claims, some prominent features of this disclosure will now be
briefly described.
[0005] One aspect of this disclosure is a network system that includes
antenna
elements and a scheduler in communication with the antenna elements. The
scheduler is
configured to receive, via at least one antenna element included in the
antenna elements,
channel state information for a user equipment. The channel state information
identifies a
quality of a transmission from one or more of the antenna elements to the user
equipment.
The scheduler is configured to determine a downlink data transmission mode to
the user
equipment based at least in part on the channel state information and
additional network
system information. The scheduler is configured to cause transmission of
active set data to
the user equipment. The active set data identifies one or more serving nodes
to provide a
wireless downlink transmission service to the user equipment in the downlink
data
transmission mode.
[0006] The additional network system information can include load
information
for coordinated multipoint resources. Alternatively or additionally, the
additional network
system information can include a characteristic of the user equipment, in
which the
characteristic comprises at least one of: an application type to utilize the
transmission service,
a protocol to utilize over the transmission service, a device type for the
user equipment, or a
mobility state of the user equipment.
[0007] The additional network system information can include a measure
of
mobility associated with the user equipment. The scheduler can be configured
to determine
the downlink data transmission mode to the user equipment is coordinated
multipoint mode
based at last in part on the measure of mobility indicating that mobility of
the user equipment
is less than a mobility threshold and the channel state information indicating
that channel
state variation is less than a threshold. The scheduler can be configured to
adjust the
downlink data transmission mode to an alternate downlink data transmission
mode based at
least in part on the measure of mobility indicating that mobility of the user
equipment is
greater than the mobility threshold or the channel state information
indicating that the
channel state variation is greater than the threshold.
2
CA 03116921 2021-04-16
WO 2020/096860 PCT/US2019/059196
[0008] The downlink data transmission mode can be a coordinated
multipoint
mode, and the scheduler can adjust the downlink data transmission mode to an
alternate
downlink data transmission mode based at least in part on updated channel
state information
and the additional network system information.
[0009] The scheduler can be further configured to cause transmission
of a mode
indicator to the user equipment, in which the mode indicator identifies the
downlink data
transmission mode.
[0010] The scheduler can be further configured to: generate a metric
indicating at
least one of: spatial channel information, motion of the user equipment, link
quality between
user equipment and one or more serving nodes included in the active set, or
network load for
transmission to the user equipment; and identify the downlink data
transmission mode based
at least in part on a comparison between the metric and a threshold.
[0011] The scheduler can be further configured to receive, from the
user
equipment, a requested active set, in which the one or more serving nodes
includes a node
that is not included in the requested active set.
[0012] The scheduler can be configured to cause first downlink traffic
to be
routed to the user equipment in an alternate downlink data transmission mode;
and cause
second downlink traffic to be routed to a second user equipment in a
coordinated multipoint
mode. The alternate downlink data transmission mode can comprises at least one
of:
synchronized transmission across multiple network nodes for coherent
combining,
transmissions across multiple network nodes for non-coherent combining, or
individual
transmission from a selected best serving node.
[0013] The scheduler can be configured to: based at least in part on
the channel
state information and the additional network system information, determine a
transmission
characteristic for the one or more serving nodes; and transmit a control
message to the one or
more serving nodes to cause adjustment of a transmitter according to the
transmission
characteristic, in which the transmission characteristic comprises at least
one of: transmission
mode, transmission time, transmission frequency, transmission power,
beamforming matrix,
tone allocation, or channel rank. The scheduler can be configured to cause
transmission of
the control message via a physical downlink control channel (PDCCH).
3
CA 03116921 2021-04-16
WO 2020/096860 PCT/US2019/059196
[0014] Another aspect of this disclosure is a method controlling a
downlink data
transmission mode for a user equipment. The method includes receiving, via at
least one
antenna element included in the antenna elements, channel state information
for a user
equipment. The channel state information identifies a quality of a
transmission from one or
more of the antenna elements to the user equipment. The method includes
determining a
downlink data transmission mode to the user equipment based at least in part
on the channel
state information and additional network system information. The method also
includes
causing transmission of active set data to the user equipment. The active set
data identifies
one or more serving nodes to provide a wireless downlink transmission service
to the user
equipment in the downlink data transmission mode.
[0015] The additional network system information can comprise load
information
for coordinated multipoint resources. Alternatively or additionally, the
additional network
system information can comprise a spatial channel condition of a channel
associated with the
user equipment. Alternatively or additionally, the additional network system
information can
comprise a characteristic of the user equipment, in which the characteristic
comprises at least
one of: an application type to utilize the transmission service, a protocol to
utilize over the
transmission service, or a device type for the user equipment.
[0016] The method can further comprise generating a metric indicating
at least
one of: spatial channel information, motion of the user equipment, link
quality between the
user equipment and one or more serving nodes included in the active set, or
network load for
transmission to the user equipment; and identifying the downlink data
transmission mode
based at least in part on a comparison between the metric and a threshold.
[0017] The method can further comprise receiving, from the user
equipment, a
requested active set, in which the one or more serving nodes includes a node
that is not
included in the requested active set.
[0018] The method can further comprise causing first downlink traffic
to be
routed to the user equipment in an alternate downlink data transmission mode;
and causing
second downlink traffic to be routed to a second user equipment in a
coordinated multipoint
mode, in which the alternate downlink data transmission mode comprises at
least one of:
synchronized transmission across multiple network nodes for coherent
combining,
4
CA 03116921 2021-04-16
WO 2020/096860 PCT/US2019/059196
transmissions across multiple network nodes for non-coherent combining, or
individual
transmission from a selected best serving node.
[0019] The method can further comprise based at least in part on the
channel state
information and the additional network system information, determining a
transmission
characteristic for the one or more serving nodes; and transmitting a control
message to the
one or more serving nodes to cause adjustment of a transmitter according to
the transmission
characteristic, in which the transmission characteristic comprises at least
one of: transmission
mode, transmission time, transmission frequency, transmission power,
beamforming matrix,
tone allocation, or channel rank.
[0020] The wireless downlink transmission service can include at least
one of:
individual network node transmission, synchronized transmission across
multiple network
nodes for coherent combining, transmissions across multiple network nodes for
non-coherent
combining, and multiple transmissions for the user equipment to select.
[0021] Another aspect of this disclosure is a network system for
downlink data
transmission in multiple-modes. The network system includes a scheduler and a
transmitter
in communication with the scheduler. The scheduler is configured to schedule a
first
downlink data transmission to a user equipment in a coordinated multi-point
mode and to
schedule a second downlink data transmission to the user equipment in an
alternative
downlink data mode. The transmitter is configured to output first data
associated with the
first downlink data transmission for transmission to the user equipment in the
coordinated
multi-point mode and to output second data associated with the second downlink
data
transmission for transmission to the user equipment in the alternative
downlink data mode.
[0022] The scheduler can be configured to provide active set data to
the
transmitter. The active set data can identify one or more serving nodes to
provide wireless
transmission service to the user equipment. The active set data can identify
different sets of
one or more serving nodes for the first downlink data transmission and the
second downlink
data transmission.
[0023] The scheduler can be configured to schedule a third downlink
data
transmission to a second user equipment in the alternative downlink data mode
concurrently
with the first downlink data transmission.
CA 03116921 2021-04-16
WO 2020/096860 PCT/US2019/059196
[0024] Another aspect of this disclosure is a user equipment that
includes antenna
elements, a receiver configured to process a signal received by the antenna
elements, and a
processor. The processor is configured to receive, from the receiver, first
active set data
identifying one or more serving nodes to provide downlink data transmission
service to the
user equipment in a coordinated multipoint mode. The processor is configured
to detect a
characteristic of the user equipment. The characteristic comprises at least
one of: an
application type to utilize the downlink data transmission service, a protocol
to utilize over
the downlink data transmission service, or a device type for the user
equipment. The
processor is configured to cause transmission, via at least one of the antenna
elements, of
channel state information for the user equipment and the characteristic. The
channel state
information identifies a quality of a transmission from a network system to
the user
equipment. The processor is configured to receive, from the receiver via at
least one of the
antenna elements, updated active set data identifying one or more serving
nodes to provide
transmission service to the user equipment in an alternate downlink data
transmission mode.
The alternate downlink data transmission mode includes at least one of
synchronized
transmission across multiple network nodes for coherent combining,
transmissions across
multiple network nodes for non-coherent combining, or individual transmission
from a
selected best serving node. The processor is configured to cause the receiver
to be adjusted
for processing the signal in the alternative downlink data transmission mode
from the one or
more serving nodes identified by the updated active set data
[0025] Another aspect of this disclosure is a method of downlink
transmission
control for a user equipment. The method includes receiving, from a receiver
of a user
equipment, a first active set data identifying one or more serving nodes to
provide downlink
data transmission service to the user equipment in a coordinated multipoint
mode. The
method also includes detecting a characteristic of the user equipment. The
characteristic
comprises at least one of: an application type to utilize the downlink data
transmission
service, a protocol to utilize over the downlink data transmission service, or
a device type for
the user equipment. The method includes causing transmission, via at least one
of a plurality
of antenna elements of channel state information for the user equipment and
the
characteristic of the user equipment. The channel state information identifies
a quality of a
transmission from a network system to the user equipment. The method further
includes
6
CA 03116921 2021-04-16
WO 2020/096860 PCT/US2019/059196
receiving, from the receiver via at least one of the antenna elements, updated
active set data
identifying one or more serving nodes to provide the downlink data
transmission service to
the user equipment in an alternate downlink data transmission mode. The
alternate downlink
data transmission mode includes at least one of synchronized transmission
across multiple
network nodes for coherent combining, transmissions across multiple network
nodes for non-
coherent combining, or individual transmission from a selected best serving
node.
[0026] Another aspect of this disclosure is a user equipment that
includes antenna
elements and a processor. The antenna elements include a first antenna
element. The
processor is configured to receive, from a base station, information
identifying an active set
of one or more serving nodes to provide transmission service to the user
equipment. The
processor is configured to determine a selected mode of wirelessly receiving
data using the
first antenna element. The selected mode is either a coordinated multipoint
mode or an
alternate downlink data transmission mode. The processor is configured to
cause
transmission, via at least one of the antenna elements, of a request to
receive data at the first
antenna element in the selected mode.
[0027] The processor can be configured to: determine a desired active
set of one
or more serving nodes to provide the transmission service to the user
equipment; and cause
transmission, via at least one of the antenna elements, of data indicative of
the desired active
set. The desired active set can include at least one serving node from the
active set.
Alternatively or additionally, the desired active set can identify at least
one serving node
from a neighbor set.
[0028] The processor can be configured to determine the selected mode
based on
data indicating a mobility state of the user equipment. The data indicating
the mobility state
can comprise at least one of Doppler estimation data or channel state
variation data.
[0029] The processor can be configured to determine the selected mode
based on
a spatial channel condition of a channel associated with the user equipment.
The processor
can be configured to: detect a spatial parameter of the channel; and generate
a channel state
estimate based at least in part on the spatial parameter of the channel, in
which the channel
state estimate indicates the spatial channel condition.
7
CA 03116921 2021-04-16
WO 2020/096860 PCT/US2019/059196
[0030] The processor can be configured to determine that the selected
mode is the
coordinated multipoint mode based on a mobility measurement being less than a
first
threshold and channel state information variation being less than a second
threshold.
[0031] The processor can be configured to determine that the selected
mode is the
alternate downlink data transmission mode based on at least one of a mobility
measurement
being greater than a first threshold or channel state information variation
being greater than a
second threshold. The processor can be further configured to: detect a
characteristic of the
user equipment, in which the characteristic comprises at least one of: an
application type to
utilize the transmission service, a protocol to utilize over the transmission
service, or a device
type for the user equipment; and generate the first threshold based at least
in part on the
characteristic.
[0032] The processor can be configured to maintain data identifying a
neighbor
set of one or more neighbor serving nodes to provide transmission service to
the user
equipment, in which the request identifies at least one neighbor serving node
from the
neighbor set.
[0033] The user equipment can further include signal processing
circuitry
configured to combine data received at the antenna elements in the coordinated
multipoint
mode and to separately process the data received by the first antenna element
in the downlink
data transmission mode.
[0034] The downlink data transmission mode can comprise at least one
of:
synchronized transmission across multiple network nodes for coherent
combining,
transmissions across multiple network nodes for non-coherent combining, or
individual
transmission from a selected best serving node. When the downlink data
transmission mode
is individual transmission from a selected best serving node, the he selected
best serving
node can be identified by at least one of the user equipment or a network
entity providing the
transmission service.
[0035] The transmission service can comprise at least one of:
individual network
node transmission, synchronized transmission across multiple network nodes for
coherent
combining, transmissions across multiple network nodes for non-coherent
combining, and
multiple transmissions for the user equipment to select.
8
CA 03116921 2021-04-16
WO 2020/096860 PCT/US2019/059196
[0036] Another aspect of this disclosure is a method of requesting a
selected
communication mode. The method includes receiving, from a base station and
with a
processor of a user equipment, an active set of one or more serving nodes to
provide
transmission service to the user equipment. The method includes determining,
using the
processor of the user equipment, a selected mode of wirelessly receiving data
using a first
antenna element of the user equipment. The selected mode is either a
coordinated multipoint
mode or an alternate downlink data transmission mode. The method also includes
wirelessly
transmitting a request to receive data at the antenna element in the selected
mode.
[0037] The method can further comprise determining, via the processor
of the
user equipment, a desired active set of one or more serving nodes for wireles
sly receiving the
data; and wirelessly transmitting data indicative of the desired active set.
The desired active
set can include at least one serving node from the active set. Alternatively
or additionally,
the desired active set can include at least one serving node from a neighbor
set.
[0038] The method can further comprise determining the selected mode
based at
least in part on data indicating a mobility state of the user equipment, in
which the data
indicating the mobility state comprises at least one of Doppler estimation
data or channel
state variation data.
[0039] The method can further comprise determining the selected mode
based at
least in part on a spatial channel condition of a channel associated with the
user equipment.
[0040] The method can further comprise detecting a characteristic of
the user
equipment, in which the characteristic comprises at least one of: an
application type to utilize
the transmission service, a protocol to utilize over the transmission service,
or a device type
for the user equipment; generating a first threshold and a second threshold
based at least in
part on the characteristic; and determining that the selected mode is the
coordinated
multipoint mode based on a mobility measurement being less than a first
threshold and
channel state information variation being less than a second threshold.
[0041] The method can further comprise detecting a characteristic of
the user
equipment, wherein the characteristic comprises at least one of: an
application type to utilize
the transmission service, a protocol to utilize over the transmission service,
or a device type
for the user equipment; generating a first threshold and a second threshold
based at least in
part on the characteristic; and determining that the selected mode is the
alternate downlink
9
CA 03116921 2021-04-16
WO 2020/096860 PCT/US2019/059196
data transmission mode based on at least one of a mobility measurement being
greater than
the first threshold or channel state information variation being greater than
a second
threshold
[0042] The alternate downlink data transmission mode can comprise at
least one
of: synchronized transmission across multiple network nodes for coherent
combining,
transmissions across multiple network nodes for non-coherent combining, or
individual
transmission from a selected best serving node wherein the selected best
serving node is
identified by at least one of the user equipment or a network entity providing
the
transmission service.
[0043] The transmission service can comprise at least one of:
individual network
node transmission, synchronized transmission across multiple network nodes for
coherent
combining, transmissions across multiple network nodes for non-coherent
combining, and
multiple transmissions for the user equipment to select.
[0044] Another aspect of this disclosure is a network system that
includes antenna
elements and a scheduler in communication with the antenna elements. The
scheduler is
configured to receive, via at least one antenna element included in the
antenna elements, a
request from a user equipment to wirelessly receive data in a particular mode,
in which the
particular mode is either a coordinated multipoint mode or an alternate
downlink data
transmission mode. The scheduler is configured to determine a downlink data
transmission
mode to the user equipment and active set data based on the request and
additional network
system information. The active set data identifies one or more serving nodes
to provide a
wireless downlink transmission service to the user equipment via the downlink
data
transmission mode. The scheduler is configured to cause transmission of active
set data to
the user equipment.
[0045] The scheduler can be configured to cause transmission of an
indication of
the downlink data mode to the user equipment.
[0046] The request can identify a user equipment active set. The
scheduler can be
configured to dynamically generate the active set data identifying the one or
more serving
nodes. The one or more serving nodes can include a node that is not included
in the user
equipment active set. Alternatively or additionally, the one or more serving
nodes can
include a node that is included in the user equipment active set.
CA 03116921 2021-04-16
WO 2020/096860 PCT/US2019/059196
[0047] The additional network system information can include load
information
for coordinated multipoint resources. The additional network system
information can include
a spatial channel condition of a channel associated with the user equipment.
The additional
network system information can include a characteristic of the user equipment.
The
characteristic can include at least one of: an application type to utilize the
transmission
service, a protocol to utilize over the transmission service, a mobility state
of the user
equipment, or a device type for the user equipment.
[0048] The scheduler can be configured to cause downlink traffic to be
routed to
the user equipment in the alternate downlink data transmission mode and to be
routed to a
second user equipment in a coordinated multipoint mode.
[0049] The alternate downlink data transmission mode can include at
least one of:
synchronized transmission across multiple network nodes for coherent
combining,
transmissions across multiple network nodes for non-coherent combining, or
individual
transmission from a selected best serving node. In certain applications, the
alternate
downlink data transmission mode can include individual transmission from the
selected best
serving mode, the scheduler can be configured to identify the selected best
serving node, and
the one or more serving nodes include the selected best serving node.
[0050] The scheduler can be configured to: based on the request and
the
additional network system information, determine a transmission power for the
one or more
serving nodes; and transmit a control message to the one or more serving nodes
to cause
adjustment of a transmitter according to the transmission power.
[0051] The wireless downlink transmission service can include at least
one of:
individual network node transmission, synchronized transmission across
multiple network
nodes for coherent combining, transmissions across multiple network nodes for
non-coherent
combining, and multiple transmissions for the user equipment to select.
[0052] Yet another aspect of this disclosure is a method of
determining and
implementing a downlink traffic mode to a user equipment. The method includes
receiving,
via at least one antenna element, a request from a user equipment to
wirelessly receive data
in a particular mode, in which the particular mode is either a coordinated
multipoint mode or
an alternate downlink data transmission mode. The method includes determining
a downlink
data transmission mode for wirelessly transmitting data to the user equipment
and active set
11
CA 03116921 2021-04-16
WO 2020/096860 PCT/US2019/059196
data based on the request and additional network system information. The
active set data
identifies one or more serving nodes to provide a wireless downlink
transmission service to
the user equipment via the downlink data transmission mode. The method also
includes
transmitting active set data to the user equipment.
[0053] The method can further include transmitting an indication of
the downlink
data transmission mode to the user equipment.
[0054] The request can identifies a user equipment active set. The
method can
further include dynamically generating the active set data identifying the one
or more serving
nodes. The one or more serving nodes can includes a node that is not included
in the user
equipment active set.
[0055] The additional network system information can include load
information
for coordinated multipoint resources. The additional network system
information can include
a spatial channel condition of a channel associated with the user equipment.
The additional
network system information can include a characteristic of the user equipment.
The
characteristic can include at least one of: an application type to utilize the
transmission
service, a protocol to utilize over the transmission service, a mobility state
of the user
equipment, or a device type for the user equipment.
[0056] The method can further include causing downlink traffic to be
routed to
the user equipment in the alternate downlink data transmission mode and to be
routed to a
second user equipment in a coordinated multipoint mode. The alternate downlink
data
transmission mode can include at least one of: synchronized transmission
across multiple
network nodes for coherent combining, transmissions across multiple network
nodes for non-
coherent combining, or individual transmission from a selected best serving
node.
[0057] The method can further include determining a transmission power
for the
one or more serving nodes based at least in part on the request and the
additional network
system information; and transmitting a control message to the one or more
serving nodes to
cause adjustment of a transmitter according to the transmission power.
[0058] The wireless downlink transmission service can include at least
one of:
individual network node transmission, synchronized transmission across
multiple network
nodes for coherent combining, transmissions across multiple network nodes for
non-coherent
combining, or multiple transmissions for the user equipment to select.
12
CA 03116921 2021-04-16
WO 2020/096860 PCT/US2019/059196
[0059] For purposes of summarizing the disclosure, certain aspects,
advantages
and novel features of the innovations have been described herein. It is to be
understood that
not necessarily all such advantages may be achieved in accordance with any
particular
embodiment. Thus, the innovations may be embodied or carried out in a manner
that
achieves or optimizes one advantage or group of advantages as taught herein
without
necessarily achieving other advantages as may be taught or suggested herein.
BRIEF DESCRIPTION OF THE DRAWINGS
[0060] Embodiments of this disclosure will now be described, by way of
non-limiting example, with reference to the accompanying drawings.
[0061] Figure 1 is a diagram illustrating a heterogeneous multiple-
input
multiple-output (MIMO) network in which user equipment (UE) and a network
system
wireles sly communicate according to an embodiment.
[0062] Figure 2 is a logical diagram illustrating which types of
wireless
communications can be provided in which modes of operation in heterogeneous
MIMO
networks.
[0063] Figure 3 is a diagram illustrating an example environment for
coordinated
multipoint communications for a UE.
[0064] Figure 4 is a diagram illustrating an example environment
including macro
diversity communications for a UE.
[0065] Figure 5 is a schematic diagram illustrating a scheduler of a
network
system in a heterogeneous MIMO wireless network according to an embodiment.
[0066] Figure 6 is a message flow diagram of an embodiment for
configuring
downlink data transmission for a user equipment.
[0067] Figure 7 is a message flow diagram of an embodiment for
updating
downlink data transmission configuration for a user equipment.
[0068] Figure 8 is a block diagram illustrating network system that
includes an
example base band unit according to an embodiment.
[0069] Figure 9 is a flow diagram illustrating an example method of
dynamically
configuring downlink data traffic modes for a user equipment in a network.
13
CA 03116921 2021-04-16
WO 2020/096860 PCT/US2019/059196
[0070] Figure 10 is a flow diagram illustrating an example method of
dynamically configuring downlink data traffic modes for a user equipment in a
network from
the user equipment's perspective.
[0071] Figure 11 is a diagram that illustrates representative
communications and
events in a heterogeneous MIMO network associated with a user equipment
requesting to
receive downlink data in a desired mode according to an embodiment.
[0072] Figure 12 is a schematic block diagram of an example UE
according to an
embodiment.
[0073] Figure 13 is a flow diagram of an example process of requesting
a selected
communication mode in which to receive data at an antenna of a UE according to
an
embodiment.
[0074] Figure 14 is a flow diagram of an example process of
controlling a
downlink data transmission mode to a UE based on a request from the UE
according to an
embodiment.
[0075] Figure 15 is a diagram illustrating allocation of active sets
and
transmission modes in a heterogeneous MIMO environment.
[0076] Figure 16A is a diagram illustrating an active set and
transmission mode
allocation in a heterogeneous MIMO environment.
[0077] Figure 16B is a diagram illustrating an updated active set and
transmission
mode allocation for the heterogeneous MIMO network of Figure 16A with updated
network
demands.
DETAILED DESCRIPTION OF CERTAIN EMBODIMENTS
[0078] The following description of certain embodiments presents
various
descriptions of specific embodiments. However, the innovations described
herein can be
embodied in a multitude of different ways, for example, as defined and covered
by the
claims. In this description, reference is made to the drawings where like
reference numerals
can indicate identical or functionally similar elements. It will be understood
that elements
illustrated in the figures are not necessarily drawn to scale. Moreover, it
will be understood
that certain embodiments can include more elements than illustrated in a
drawing and/or a
subset of the elements illustrated in a drawing. Further, some embodiments can
incorporate
14
CA 03116921 2021-04-16
WO 2020/096860 PCT/US2019/059196
any suitable combination of features from two or more drawings. The headings
provided
herein are for convenience only and do not necessarily affect the scope or
meaning of the
claims.
[0079] A distributed coordinated multiple-input multiple-output (MIMO)
network
that is designed to provide high uniform data rates across the network can
face a number of
significant challenges. Such challenges can include servicing devices in
mobility and/or
providing reliable data service in the case of poor channel conditioning, such
as when most
of the devices are clustered around a few antenna nodes. Technology disclosed
herein can
enable high data rate and high reliability for devices across Doppler and
different channel
conditions in a distributed MIMO network, thereby extending the benefits of
distributed
MIMO to larger set of devices reliably across the network. Such a network can
provide low
latency and high throughput with low jitter. Efficient quality of service at
high user density
can also be achieved with such a network. Highly robust connections can enable
mobile
edge computing.
[0080] In addition, there can be challenges with scalability across a
wide area
network and/or complexity of implementing a distributed MIMO network at scale.
Technology disclosed herein can scale across a wide area network without
significantly
adding to complexity at scale.
[0081] Aspects of this disclosure relate to a unified coordinated MIMO
network
across multiple transmit-receive points (TRPs) to serve devices in different
channel
conditions. Available network resources can be dynamically partitioned to be
used between
coordinated multi-point (CoMP) operation and an alternative downlink data
transmission
mode of operation (e.g., single-frequency network (SFN), non-coherent
combining (soft
handoff), best server selection SIMO (single-input multiple-output), best
server selection
single user MIMO (SU-MIMO), best server selection multi-user MIMO (MU-MIMO),
etc.).
Accordingly, a unified framework for operating in CoMP or the alternative
downlink data
transmission mode of operation is provided. The network and UE (user
equipment) can use a
criterion based on a set of metrics to determine the best operating regime to
serve a given
antenna and/or device for downlink data transmission. The metrics can include
a device
mobility state, a Doppler estimate, a measure of the network-to-UE channel
matrix condition
such as Eigen-value spread, a network congestion measure (e.g., network load),
the like, or
CA 03116921 2021-04-16
WO 2020/096860 PCT/US2019/059196
any suitable combination thereof. The UEs in mobility or with an ill-
conditioned channel
matrix can operate in the alternative downlink data transmission mode for
reliability, whereas
other UEs can be served with CoMP to increase and/or maximize overall system
capacity.
[0082] The technology disclosed herein relates to a wireless
communication
system with resources to operate in both CoMP mode and at least one
alternative downlink
data transmission mode. Moreover, the technology described herein provides a
mechanism
that enables the network to select the best mode of operation from between
CoMP mode and
at least one alternative downlink data transmission mode. User equipment can
request to
receive data in either CoMP mode or the alternative downlink data transmission
mode. The
wireless systems disclosed herein can enable robust, consistently high data
rate, ultra-low
latency wireless connection within a dense network. The wireless systems
disclosed herein
are applicable to user equipment with a variety of mobility and/or link
conditions.
[0083] The network and UEs may collect a set of monitoring metrics,
which can
include one or more of a channel matrix condition for each UE via measuring
Eigen spread,
UE mobility via Doppler estimation, network load via scheduling metrics, and
measure of
UE channel state information (CSI), or throughput over time. The channel state
information
may identify a quality of a transmission from one or more antenna elements
(e.g., a MIMO
antenna array) to the user equipment. The network can make a determination of
the best
downlink data transmission mode to a particular UE based on the metrics. The
network can
serve a UE in CoMP mode when conditions are suitable for CoMP mode. However,
the
network can serve the UE in the alternative downlink data transmission mode in
response to
detecting a condition indicating that CoMP mode is undesirable. For example,
for a UE with
a Doppler estimation exceeding a threshold or the channel Eigen spread larger
than another
threshold, the network can serve the UE in the alternative downlink data
transmission mode.
As another example, if the network is overly congested in CoMP mode, UEs with
less
favorable channel conditions can be served in the alternative downlink data
transmission
mode.
[0084] Technology disclosed herein can use UE channel conditions to
significantly improve the robustness of a coordinated MIMO network to ensure
reliability in
serving the users in adverse channel conditions while achieving high data
capacity across the
network for low mobility users. The technology disclosed herein provides a
comprehensive
16
CA 03116921 2021-04-16
WO 2020/096860 PCT/US2019/059196
consideration of operation regimes and the flexibility to choose the best one
for a particular
set of conditions.
Heterogeneous MIMO Network
[0085] Figure 1 is a diagram illustrating a heterogeneous multiple-
input
multiple-output (MIMO) network in which user equipment (UE) and a network
system
wirelessly communicate according to an embodiment. The heterogeneous MIMO
network
can implement a downlink coordinated joint transmission and/or reception
across distributed
antennas in a coordinated multipoint (CoMP) mode. The heterogeneous MIMO
network can
also implement a macro diversity mode for wirelessly communicating between UEs
and the
network system. The network system can partition system resources between the
different
modes of operation. For example, carriers in the frequency domain can be used
to partition
resources between the different modes of operation. Alternatively or
additionally, time slots
can be used to partition resources between the different modes of operation in
the time
domain.
[0086] The heterogeneous MIMO network provides a unified approach to
serve
low mobility and high mobility UEs. In addition, the heterogeneous MIMO
network can
implement robust processing to handle singularities. The heterogeneous MIMO
network an
address diverse channel conditions to provide spectrally efficient service.
Network system
spectral efficiency can be increased by dynamic load balancing.
[0087] Figure 1 shows an example environment for distributed MIMO
wireless
communications. Various standards and protocols may be included in the
environment 100 to
wirelessly communicate data between a base station and a wireless
communication device.
Some wireless devices may communicate using an orthogonal frequency-division
multiplexing (OFDM) digital modulation scheme via a physical layer. OFDM
standards and
protocols can include the third generation partnership project (3GPP) long
term evolution
(LTE), the Institute of Electrical and Electronics Engineers (IEEE) 802.16
standard
(e.g., 802.16e, 802.16m), which may be known as WiMAX (Worldwide
interoperability for
Microwave Access), and the IEEE 802.11 standard, which may be known as Wi-Fi.
In some
systems, a radio access network (RAN) may include one or more base station
associated with
one or more evolved Node Bs (also commonly denoted as enhanced Node Bs,
eNodeBs, or
17
CA 03116921 2021-04-16
WO 2020/096860 PCT/US2019/059196
eNBs, gNBs, or any other suitable Node Bs (xNBs)). In other embodiments, radio
network
controllers (RNCs) may be provided as the base stations. A base station
provides a bridge
between the wireless network and a core network such as the Internet. The base
station may
be included to facilitate exchange of data for the wireless communication
devices of the
wireless network.
[0088] The wireless communication device may be referred to a user
equipment
(UE). The UE may be a device used by a user such as a smartphone, a laptop, a
tablet
computer, cellular telephone, a wearable computing device such as smart
glasses or a smart
watch or an ear piece, one or more networked appliances (e.g., consumer
networked
appliances or industrial plant equipment), an industrial robot with
connectivity, or a vehicle.
In some implementations, the UE may include a sensor or other networked device
configured
to collect data and wirelessly provide the data to a device (e.g., server)
connected to a core
network such as the Internet. Such devices may be referred to as Internet of
Things devices
(IoT devices). A downlink (DL) transmission generally refers to a
communication from the
base transceiver station (BTS) or eNodeB to the wireless communication device,
and an
uplink (UL) transmission generally refers to a communication from the wireless
communication device to the BTS.
[0089] Figure 1 illustrates a cooperative, or cloud radio access
network (C-RAN)
environment 100. In the environment 100, the eNodeB functionality is
subdivided between a
base band unit (BBU) 110 and multiple remote radio units (RRUs) (e.g., RRU
125,
RRU 135, and RRU 145). An RRU may include multiple antennas, and one or more
of the
antennas may serve as a transmit-receive point (TRP). The RRU and/or a TRP may
be
referred to as a serving node. The BBU 110 may be physically connected to the
RRUs such
as via an optical fiber connection. The BBU 110 may provide operational
details to an RRU
to control transmission and reception of signals from the RRU along with
control data and
payload data to transmit. The RRU may provide data to the network received
from UEs
within a service area associated with the RRU. As shown in Figure 1, the RRU
125 provides
service to devices with a service area 120. The RRU 135 provides service to
devices within a
service area 130. The RRU 145 provides service to devices within a service
area 140. For
example, wireless downlink transmission service may be provided to the service
area 140 to
communicate date to one or more devices within the service area 140.
18
CA 03116921 2021-04-16
WO 2020/096860 PCT/US2019/059196
[0090] The RRUs may include multiple antennas to provide multiple in
multiple
out (MIMO) communications. For example, an RRU may be equipped with various
numbers
of transmit antennas (e.g., 1, 2, 4, 8, or more) that can be used
simultaneously for
transmission to one or more receivers, such as a user equipment (UE).
Receiving devices
may include more than one receive antenna (e.g., 2, 4, etc.). The array of
receive antennas
may be configured to simultaneously receive transmissions from the RRU. Each
antenna
included in an RRU may be individually configured to transmit and/or receive
according to a
specific time, frequency, power, and direction configuration. Similarly, each
antenna
included in a UE may be individually configured to transmit or receive
according to a
specific time, frequency, power, and direction configuration. The
configuration may be
provided by the BBU 110. The direction configuration may be generated based on
network
estimate using channel reciprocity or determined based on feedback from UE via
selection of
a beamforming codebook index, or a hybrid of the two.
[0091] The service areas shown in Figure 1 may provide communication
services
to a heterogeneous population of user equipment. For example, the service area
120 may
include a cluster of UEs 160 such as a group of devices associated with users
attending a
large public event. A mobile user equipment 170 may move from the service area
130 to the
service area 140. Another example of a mobile user equipment is a vehicle 156
which may
include a transceiver for wireless communications for real-time navigation, on-
board data
services (e.g., streaming video or audio), or other data applications. The
environment 100
may include semi-mobile or stationary devices such as robotic device 158
(e.g., robotic arm,
autonomous drive unit, or other industrial or commercial robot), or a
television 154 also
configured for wireless communications.
[0092] A user equipment 152 may be located with an area with
overlapping
service (e.g., the service area 120 and the service area 130). Each device in
the
environment 100 may have different performance needs which may, in some
instances,
conflict with the needs of other devices.
[0093] Figure 2 is a logical diagram illustrating which types of
wireless
communications can be provided in which modes of operation in heterogeneous
MIMO
networks. Macro diversity communications may be allocated for messages related
to
acquiring service, requesting access to the service, and control messages for
the service. Data
19
CA 03116921 2021-04-16
WO 2020/096860 PCT/US2019/059196
traffic may be communicated using either macro diversity communication mode or
coordinated multipoint mode for data traffic. Accordingly, the macro diversity
mode is an
alternative downlink data transmission mode. The alternative downlink data
mode can be the
mode in which acquisition, access, and control communications are
communicated. The
macro diversity mode or the coordinated multipoint mode can be selected based
on any
suitable criteria disclosed herein.
[0094] Figure 3 is a diagram illustrating an example environment for
coordinated
multipoint communications for a UE. In the environment 300, the UE 152 may
receive
downlink data traffic from the RRU 125 and the RRU 135 with each RRU sending
one or
more spatial layers via respective TRPs included in the RRU. Each spatial
layer can
correspond to a beam. The spatial layers may be coordinated such as by using a
weighted
combination for each layer to provide transmissions to a specific UE.
Different sets of
weighted combinations can be provided for different UEs. The transmissions
from the
RRU 125 and the RRU 135 may be coordinated by the base band unit 110.
Coordination may
include coordinating the timing of transmissions and data included in
transmissions for the
UE 152. The RRU 125 may use a first channel 310 to transmit data to the UE 152
while the
RRU 135 may use a second channel 320 to transmit data to the UE 152 where the
first and
second channel are the same for CoMP.
[0095] Figure 4 is a diagram illustrating an example environment
including macro
diversity communications for a UE. In the environment 400, a UE 410 may
receive data
traffic over a channel 420 from the RRU 125. The RRU 125 may be selected by
the
BBU 110 as the best serving node for the UE 410. The evaluation may be based
on signal
strength, channel state information (CSI) reports received from the UE 410,
mobility of the
UE 410, spatial channel condition of a channel for the UE 410, or other
factors of the
environment 400 detectable by the BBU 110. In some implementations, the UE 410
may
request the serving node. The UE 410 may identify the RRU 125 based on signal
strength,
anticipated data to be transmitted to or from the UE 410, or a control message
received from
the BBU 110. Another example of a macro diversity communication mode is
individual
network node transmissions from a selected node.
[0096] A further example of a macro diversity communication mode is
synchronized transmissions across multiple RRU that are coherently combined by
the
CA 03116921 2021-04-16
WO 2020/096860 PCT/US2019/059196
UE 410. In this mode, each RRU may transmit downlink data traffic and the UE
410 may
decode portions of different transmissions to assemble the data. The decoding
may be based
on transmission information (e.g., coefficients) shared between the
transmitting RRU and the
UE 410. Another example of a macro diversity communication mode is non-
coherent
combination of transmissions from multiple RRUs. In non-coherent systems, the
UE 410
may decode received transmissions based on statistical information (e.g.,
coefficients)
derived from received signal characteristics from one or more RRU's, not
necessarily time
aligned, and combine the received data as part of the demodulation process or
combine post
decode. In CoMP mode, different TRPs transmit different spatial layers (e.g.,
different data)
to one or more UEs. In a macro diversity mode, the transmission may be sent
from either
one TRP or the same data across multiple TRPs.
[0097] Existing systems are configured to use one communication mode,
system-
wide, for the downlink data traffic. By using only one downlink data traffic
mode, systems
may provide suboptimal service to at least some of the devices served. For
example, in cases
where a service area includes a high density of UEs concentrated near one of
the many RRUs
in the area, the beamforming and other transmission coordination needed to
provide a high
quality service to all UEs in the dense area may cause a substantial downgrade
in the
communication rate within a service area utilizing coordinated multipoint
methods.
Similarly, in cases where a UE is moving rapidly, CoMP methods may incur
substantial
overhead to provide service to the moving UE.
[0098] To indicate the downlink data traffic mode, the BBU 110 may
communicate one or more identifiers to a UE. The identifiers indicate the RRUs
providing
downlink data traffic to the UE. The set of identifiers may be referred to as
an active set for
the UE. In a macro diversity mode, the active set may include the identifier
of a single RRU
or a group of RRUs transmitting the same data to the UE for soft-combining
(SFN) or non-
coherent combining (soft handoff). In a coordinated multipoint mode, the
active set may
include the identifiers of the RRUs coordinating to provide one or more
spatial layers of
downlink data traffic to the UE.
[0099] As described in further detail below, the BBU 110 may
dynamically assess
characteristics of the network or the UE to determine which mode to use for
downlink data
traffic for a UE. This allows the BBU 110 to selectively communicate with UEs
based on
21
CA 03116921 2021-04-16
WO 2020/096860 PCT/US2019/059196
network conditions or operational needs of the UE. This also allows the BBU
110 to allocate
transmission resources in consideration of overall network impact rather than
treating each
UE as an independent assignment that has no impact on the traffic mode
assigned for other
devices.
[0100] The environment 100 shown in Figure 1 may represent a portion
of a
larger environment including additional or alternative base band units coupled
with
additional or alternative remote radio units.
Mode Determination
[0101] A downlink data transmission mode can be dynamically determined
in a
heterogeneous MIMO network. As discussed above, the downlink data transmission
mode
can be either a CoMP mode or an alternative downlink data transmission mode.
The
alternative downlink data transmission mode can be any of the macro diversity
modes
disclosed herein. The alternative downlink data transmission mode can be the
mode in which
acquisition, access, and control communications are communicated. A network
scheduler
can determine the downlink data transmission mode from a base station to a UE
and/or to one
or more particular antennas of a UE. The downlink data transmission mode can
be selected
based on a network centric determination or a UE assisted determination. The
network
centric determination can be based on a UE report and system load data. The UE
assisted
determination can be based on a request to receive downlink transmission data
in a selected
mode by a UE. More details regarding technical features of network centric
mode
determination and UE assisted mode determination are provided herein.
[0102] The desired mode of operation can be selected by a scheduler
based on
any suitable information. One or more of the following types of information
can be used in
determining a downlink data transmission mode: UE link quality, UE mobility
data, a
network to UE channel matrix condition, or network loading. Mobility data,
such as Doppler
estimation and/or channel state information (CSI) variation, can be used in
determining the
desired mode. With more mobility, CoMP mode can be more difficult and/or less
effective.
For instance, when a mobile phone is being used on a fast moving train, CoMP
can be
difficult due to poor channel estimates as a result of, for example, the fast
changing channel
conditions and an alternative downlink data transmission mode can be selected.
A network
22
CA 03116921 2021-04-16
WO 2020/096860 PCT/US2019/059196
to UE channel matrix condition, such as a CSI estimation, can be used in
determining the
desired mode. The alternative downlink data transmission mode can be used when
a network
to UE channel matrix is undesirable and/or unsuitable for CoMP. Network
loading data can
be used to generate interference data in a base station. Such network loading
data can be
used by a scheduler to determine the selected mode of operation. As an
example, a scheduler
can select the alternative downlink data transmission mode in response to the
network data
indicating a relatively high load on CoMP resources.
[0103] The scheduler can select a mode of downlink data transmission
from one
or more serving nodes to a user equipment. The network scheduler can select
CoMP as the
selected mode in response to determining that conditions are suitable for
CoMP. Otherwise,
the network scheduler can select the alternative downlink data transmission
mode as the
desired mode.
[0104] The scheduler can select CoMP as the selected mode in response
to
determining that mobility is less than a threshold. The mobility can be
determined by a
mobility measure of a UE, such as CSI or a Doppler estimate. Alternatively or
additionally,
the scheduler can select CoMP as the selected mode in response to determining
that the
difference between maximum and mean Eigen-values of a downlink channel matrix
is less
than a threshold. For example, the scheduler can select CoMP as the selected
mode in
response to determining that (1) mobility is less than a first threshold, (2)
the difference
between maximum and mean Eigen-values of a downlink channel matrix are less
than a
second threshold, (3) an estimated relative spectral efficiency for serving
CoMP mode to the
UE is higher than for the alternative downlink data transmission mode, or (4)
any suitable
combination of (1) to (3). For example, the CoMP mode can be selected by (1),
(2) and (3).
As another example, CoMP mode can be selected by any two of (1), (2), or (3).
In some
instances, CoMP mode can be selected by any one of (1), (2), or (3). The first
threshold
and/or the second threshold can be adjustable based on one or more
characteristics associated
with a UE. The one or more characteristics of the UE can include a device
type, a software
program running on a UE, a protocol, a use case, the like, or any suitable
combination
thereof.
[0105] The scheduler can select the alternative downlink data
transmission mode
as the selected mode in response to determining that a condition indicates
that CoMP mode is
23
CA 03116921 2021-04-16
WO 2020/096860 PCT/US2019/059196
undesirable. Such a condition can include one or more of mobility being
sufficiently high, a
relatively low Eigen spread of a downlink channel matrix for a UE, or a
sufficiently high
load is detected on CoMP resources. Accordingly, the scheduler can select the
alternative
downlink data transmission mode as the selected mode in response to
determining that (1)
mobility is sufficiently high or (2) there is a relatively low Eigen spread of
a downlink
channel matrix for a UE or (3) there is a sufficiently high load is detected
on CoMP resources
or (4) an estimated relative spectral efficiency for serving the alternative
downlink data mode
to the UE is higher than for the CoMP mode. Mobility can be sufficiently high
when
mobility exceeds the first threshold. The load on CoMP resources can be based
on detecting
interference and/or a relatively large number of UEs in proximity to each
other. A
sufficiently high load on CoMP resources can involve the number of UEs being
significantly
greater than the number of distributed antennas of a heterogeneous MIMO
network.
[0106] The scheduler may be implemented as a discrete hardware device.
The
scheduler may include one or more communication ports to transmit and/or
receive messages
via a network. For example, the scheduler may be communicatively coupled with
a BBU to
provide at least a portion of the scheduling features described. In some
implementations, the
scheduler may be integrated within a BBU. The scheduler may be implemented
using
specifically configured circuitry to provide at least a portion of the
scheduling features
described. In some implementations, the scheduler may include a processor
configured by
specific instructions stored in a non-transitory data store. When the
processor executes the
specific instructions, it may cause the scheduler to perform at least a
portion of the
scheduling features described.
[0107] Figure 5 is a schematic diagram illustrating a heterogeneous
MIMO
wireless network 500 that includes a baseband unit 510 according to an
embodiment. As
illustrated, the baseband unit 510 includes a user data queue block 512, a
scheduler
control 514, a time/frequency resource allocation block 516, an active set and
beam
management block 518, a transceiver 520, a CSI computation block 522, and an
active set
serving node update block 524. The baseband unit 510 can include any suitable
physical
hardware to implement the illustrated blocks. For example, the baseband unit
510 can
include a processor and computer readable storage to implement any suitable
blocks shown
24
CA 03116921 2021-04-16
WO 2020/096860 PCT/US2019/059196
in Figure 5. The
heterogeneous MIMO wireless network 500 also includes user
equipment 560 and 565 and serving nodes 570, 580, and 590.
[0108] The
baseband unit 510 includes a scheduler that schedules user data for
wireless transmission from serving nodes 570, 580, and 590 to user equipment
560 and 565.
The scheduler can schedule downlink data traffic in both the CoMP mode and the
alternative
downlink data transmission mode. For example, the scheduler can schedule
downlink data
traffic to one UE in the CoMP mode and to another UE in the alternative
downlink data. As
another example, the scheduler can schedule downlink data traffic to a UE in
the CoMP
mode at a first time and to the UE in the alternative downlink data at a
second time. The
serving nodes can alternatively be referred to as transmission points for
downlink data
transmission. The scheduler can schedule data from any suitable number of
serving nodes to
any suitable number of user equipment. The scheduler can include the user data
queue
block 512, the scheduler control 514, the time/frequency resource allocation
block 516, the
active set and beam management block 518, the CSI computation block 522, and
the active
set serving node update block 524.
[0109] The
transceiver 520 can provide a UE report from the user equipment 560
and/or 565 to the scheduler. The UE report can include CSI information and
active set
information. The UE report can also include any other suitable information
from a UE, such
as other information from which to determine a selected mode of downlink data
transmission.
The CSI computation block 522 can compute CSI data from data in the UE report.
The
active set serving node update block 524 can determine an updated active set
for one or more
UEs. In some instances, the active set serving node update block 524 can
determine an
updated active set for a subset of one or more antennas of a UE. The active
set serving node
update block 524 can use any suitable metrics disclosed herein to determine a
selected
downlink data transmission mode and update an active set associated with a UE.
[0110] The
updated active set data is provided to the scheduler control 514. The
user data queue block 512 can provide user data to the scheduler control 514.
The schedule
control 514 provides user data to the transceiver 520 and also provides
instructions to the
time/frequency resource allocation block 516. The time/frequency resource
allocation
block 516 can schedule timing and frequency of downlink data transmission from
serving
nodes 570, 580, and 590. This can avoid timing conflicts and conflicts in the
frequency
CA 03116921 2021-04-16
WO 2020/096860 PCT/US2019/059196
domain. The
active set and beam management block 518 can identify serving
nodes 570, 580, and 590 for providing wireless transmission services to UEs
560 and 565
from active set data. The active set and beam management block 518 can group
downlink
data transmissions and manage beamforming from the serving nodes 570, 580, and
590 to
UEs 560 and 565. The transceiver 520 provides data for transmission by the
serving
nodes 570, 580, and 590 to UEs 560 and 565.
[0111] As
shown in Figure 5, the scheduler can cause a network system of the
heterogeneous MIMO wireless network 500 to wirelessly transmit first user data
to a first
user equipment 565 in CoMP mode and to wirelessly transmit second user data to
a second
user equipment 560 in an alternative downlink data transmission mode.
Moreover, the
scheduler can cause a network system of the heterogeneous MIMO wireless
network to
wirelessly transmit user data to any suitable number of UEs in CoMP mode and
any suitable
number of UEs in the alternative downlink data transmission mode.
Network Centric Communication Mode Determination
[0112]
Figure 6 is a message flow diagram of an embodiment for configuring
downlink data transmission for a user equipment. The message flow 600
illustrates example
messages that may be transmitted between a user equipment 610, a remote radio
unit 620,
and a base band unit 630. Additional or alternative entities may be include to
mediate one or
more of the interactions shown such as network routers, switches, security
devices, or the
like.
[0113] Via
message 650, the UE 610 may request network services via the
RRU 620. The connection request may include an identifier for the UE 610 such
as a MEID
or UUID of the UE 610. In some implementations, the identifier may be
associated with
account information indicating service levels and other network services
accessible by the
UE 610. The message 650 may be received via a wireless communication channel
connecting
the UE 610 with the RRU 620.
[0114] Via
message 652, the RRU 620 may request connection for the UE 610
from the BBU 630. The request may include the identifier for the UE 610 along
with an
identifier of the RRU 620 receiving the connection request from the UE 610.
The
26
CA 03116921 2021-04-16
WO 2020/096860 PCT/US2019/059196
message 652 may be transmitted from the RRU 620 to the BBU 630 using a wired
or a
wireless communication channel.
[0115] Via message 654, the BBU 630 may generate an active set of one
or more
serving nodes (e.g., RRUs or TRPs) to provide the requested service to the UE
610. The
generation of the active set may include generating scheduling information for
the UE 610.
The scheduling information may identify one or more of transmission mode,
time, frequency,
power, beamforming matrix, tone allocation, or channel rank for downlink data
transmissions
to the UE 610. The generation of the active set may include consideration of
network system
information such as a network load. For example, if the number of UEs serviced
by the
RRU 620 exceeds a threshold, it may be desirable to assign an active set
representing a
macro diversity transmission mode.
[0116] Via message 656, the BBU 630 may transmit the downlink
scheduling
parameters to the RRU 620. The parameters may include transmission mode, time,
frequency, power, beamforming matrix, tone allocation, or channel rank. The
RRU 620 may
transmit a message 658 to the UE 610 indicating the active set for the
requested downlink
transmission service. The message 658 may include transmission parameters the
UE 610 may
expect from the active set (e.g., transmission mode, time, frequency, power,
beamforming
matrix, tone allocation or rank).
[0117] The UE 610 may, via message 660, adjust a transceiver or other
signal
processing circuitry based on the parameters received via message 658. The
adjustment may
include tuning one or more antennas of the UE 610. The adjustment may include
changing
demodulation and/or decoding pipeline for the UE 610 to properly interpret
downlink
messages. For example, if the UE 610 is initially assigned a CoMP mode,
subsequent
conditions may cause the BBU 630 to change the UE 610 to a macro diversity
mode. The
manner in which received messages are processed (e.g., decoded) may require a
change in
the demodulation and/or decoding pipeline or other element of the UE 610 to
ensure
continuity of a data transaction as the mode changes.
[0118] Via message 662, the RRU 620 may adjust a transceiver or other
signal
processing circuitry based on the downlink scheduling parameters received via
message 656.
The adjustment of the RRU 620 may occur concurrently or at an overlapping time
with the
adjustment of the UE 610.
27
CA 03116921 2021-04-16
WO 2020/096860 PCT/US2019/059196
[0119] Having configured both the RRU 620 and the UE 610 for the
downlink
data transmission mode identified by the BBU 630, messaging 664 may carry data
between
the UE 610 and the RRU 620. Other RRUs (not shown) may be configured by the
BBU 630
to provide downlink data transmission services. For example, if the downlink
transmission
mode is a coordinated multipoint mode, the RRU 620 and at least one additional
RRU may
be configured to transmit data to the UE 610. The uplink and downlink data
transmissions
can be in different modes. Alternatively or additionally, the uplink and
downlink data
transmissions can have different associated active sets. For instance, there
can be a downlink
active set and an uplink active set.
[0120] The messaging in Figure 6 illustrates how an initial active set
and network
tuning parameters for a first transmission mode may be identified for a UE. As
discussed,
today's networks are dynamic ecosystems with devices moving, powering on,
powering off,
and such. These dynamic conditions may cause an initial assessment of a
downlink
transmission mode to change based on changing network and/or UE
characteristics.
[0121] Figure 7 is a message flow diagram of an embodiment for
updating
downlink data transmission configuration for a user equipment. The message
flow 700
illustrates example messages that may be transmitted between a user equipment
710, a
remote radio unit 720, and a base band unit 730. Additional or alternative
entities may be
include to mediate one or more of the interactions shown such as network
routers, switches,
security devices, or the like.
[0122] Via message 750, the UE 710 may detect UE conditions. The UE
conditions that may be detected include channel conditions of the connection
with the
RRU 720. Channel conditions may include signal strength, signal-to-noise
ratio, spatial
characteristics, Doppler information, UE capability changes such as active
receive and/or
transmit antennas. The UE conditions may include an operational characteristic
of the
UE 710 such as the application(s) executing on the UE 710, communication
protocols used
by the application(s) executing on the UE 710, or motion of the UE 710 (e.g.,
Doppler
estimation or channel state variation). The UE conditions may include
information about the
UE 710 such as device type, operating system, peripheral devices attached to
the UE 710, or
the like.
28
CA 03116921 2021-04-16
WO 2020/096860 PCT/US2019/059196
[0123] Via message 752, the UE 710 may provide at least a portion of
the UE
conditions detected via message 750 to the RRU 720. The message 752 may
include a
channel state information (CSI) report. In some implementations, the message
752 may
include multiple messages, each message including different UE conditions.
[0124] Via message 754, the RRU 720 may transmit the condition
information to
the BBU 730. The message 754 may include identifiers for the UE 710 and the
RRU 720 to
allow the BBU 730 to associate the condition information with a specific
downlink channel
(e.g., UE and RRU combination).
[0125] Based at least in part on the UE condition information along
with network
condition information that may be detected by the BBU 730, via message 756,
the BBU 730
may generate a downlink schedule for the UE 710. The generation via message756
may be
similar to the generation via message 654 shown in Figure 6. However, in
Figure 7 the
UE 710 may already have an initial active set and transmission mode
identified. This initial
active set and/or transmission mode may be changed due to changes in network
conditions or
UE condition information.
[0126] The BBU 730 may provide downlink scheduling parameters to the
RRU 720. The parameters may include one or more of transmission mode, time,
frequency,
power, beamforming matrix, tone allocation, or channel rank. The RRU 720 may
transmit a
message 760 to the UE 710 indicating the active set and/or scheduling
parameters for the
requested downlink transmission service. The message 760 may include
transmission
parameters the UE 710 may expect from the active set (e.g., transmission mode,
time,
frequency, power, beamforming matrix, tone allocation, or channel rank). The
message 760
may include an indication of the transmission mode identified for the UE 710.
[0127] The UE 710 may, via message 762, adjust a transceiver, a
receiver (e.g., a
receiver of a transceiver), or other signal processing circuitry based on the
parameters
received via message 760. The adjustment may include tuning one or more
antennas of the
UE 710. The adjustment may include changing demodulation and/or decoding
pipeline for
the UE 710 to properly interpret downlink messages. For example, if the UE 710
is initially
assigned a CoMP mode, subsequent conditions may cause the BBU 730 to change
the
UE 610 to a macro diversity mode. The manner in which received messages are
processed
29
CA 03116921 2021-04-16
WO 2020/096860 PCT/US2019/059196
(e.g., decoded) may require a change in the demodulation and/or decoding
pipeline or other
element of the UE 710 to ensure continuity of a data transaction as the mode
changes.
[0128] Via message 764, the RRU 720 may adjust a transceiver or other
signal
processing circuitry based on the downlink scheduling parameters received via
message 758.
The adjustment of the RRU 720 may occur concurrently or at an overlapping time
with the
adjustment of the UE 710.
[0129] Having configured both the RRU 720 and the UE 710 for the
downlink
data transmission mode identified by the BBU 730, messaging 766 may carry data
between
the UE 710 and the RRU 720. Other RRUs (not shown) may be configured by the
BBU 730
to provide downlink data transmission services. For example, if the downlink
transmission
mode is a coordinated multipoint mode, the RRU 720 and at least one additional
RRU may
be configured to transmit data to the UE 710.
[0130] Figure 8 is a block diagram illustrating an example base band
unit and
remote radio unit according to an embodiment. The base band unit 820 may be
coupled with
at least one remote radio unit 890. The remote radio unit 890 may include at
least a first
antenna 896 and a second antenna 898 for MIMO wireless communications. Any
antenna
disclosed herein, such as the antenna 896 or the antenna 898, can be referred
to as antenna
element. The first antenna 896 and the second antenna 898 may be coupled with
a radio
frequency (RF) front end 894. The RF front end 894 may process signals
received via the
first antenna 896 and the second antenna 898. Part of processing a signal may
include
transmitting the signal to a transceiver 820 included in the BBU 802.
[0131] A processor 805 may receive signals received by the transceiver
820. The
processor 805 may be configured to determine a type of the signal. For
example, if the signal
includes a request for connection services, the processor 805 may provide the
signal to an
active set selector 835. The active set selector 835 may be configured to
identify an active set
of serving nodes to provide the requested downlink data transmission service.
The active set
selector 835 can identify the active set for a UE based on information
associated with the UE.
Alternatively or additionally, the active set selector 835 can identify the
active set for a UE
based on information associated with one or more other UEs. In some instances,
the active
set selector 835 can determine a transmission mode for the downlink data
transmission
service. The BBU 802 may include a network monitor 825 to detect
characteristics of the
CA 03116921 2021-04-16
WO 2020/096860 PCT/US2019/059196
network such as the number of UEs server by each RRU, network data
transmission load, or
the like. The active set selector 835 may receive the network characteristics
from the network
monitor 825 as a factor considered when identifying an active set and/or
transmission mode
for a UE request. A beamformer 815 may be included in the BBU 802 to further
identify
parameters for the serving nodes (e.g., RRUs) included in an active set. The
parameters may
include one or more of transmission mode, time, frequency, power, beamforming
matrix,
tone allocation, or channel rank. The beamformer 815 may determine optimal
parameters for
RRUs coupled with the BBU 802 that facilitate a network-wide optimization of
downlink
data transmissions. In some implementations, a UE may provide a requested
active set. The
BBU 802 may include an active set arbitrator 830 to reconcile a requested
active set with an
active set selected by the active set selector 835. The active set arbitrator
830 may compare a
requested set of serving nodes to the serving nodes identified by the active
set selector 835.
The comparison may include ordering the serving nodes according to the UE
recommendation. In some implementations, the active set arbitrator 830 may
provide a
message to the UE indicating confirmation or other assessment for a requested
active set. For
example, if the UE requested nodes A and B but the BBU 802 identified only B
in the active
set, the message may include a code indicating a partial match for the active
set. Other status
codes may be included to facilitate efficient communication and assessment of
requested
active sets. The active set arbitrator 830 may additionally or alternatively
compare a
requested transmission mode to the transmission mode identified by the active
set
selector 835 or other element of the BBU 802.
[0132] The BBU 802 may include a data store 810. The data store 810
may
include instructions that can be executed by the processor 805 to implement
the features
described. In some implementations, the data store 810 may retain active sets
or other
scheduling information assigned to UEs served by the BBU 802. The data store
810 may be
indexed by UE identifier and/or RRU identifier. This can expedite
identification of
previously communicated scheduling information for the UE and for monitoring
network
conditions (e.g., number of UEs allocated to an RRU or antenna element of an
RRU).
[0133] In addition to providing the scheduling information to the UE,
the
scheduling information may be used to configure the RRU 890. The configuration
may
include adjusting the first antenna 896 such as by frequency modulation, time
modulation,
31
CA 03116921 2021-04-16
WO 2020/096860 PCT/US2019/059196
altering transmission power from a power source 892, or adjusting direction,
tone allocation,
or beamforming of the transmission.
[0134] Figure 9 is a flow diagram illustrating an example method of
dynamically
configuring downlink data traffic modes for a user equipment in a network. The
method 900
may be performed in whole or in part under control of a coordination device
such as a base
band unit. The method 900 demonstrates features for identifying coordinated
multipoint
communication or an alternate mode for downlink data traffic to a UE. The
identification
includes assessment of network conditions along with properties of the UE to
receive the
service. A non-transitory computer readable storage medium can store specific
instructions
that, when executed, cause some or all of the method 900 and/or some or all of
any other
suitable method disclosed herein to be executed.
[0135] The method 900 may begin at block 902. At block 904, the
coordination
device may receive channel state information for a user equipment. The channel
state
information may be received as part of a CSI report transmitted by the user
equipment. The
channel state information may include channel quality indicators for one or
more channels
available to the UE. The channel state information may include precoding
information such
as a preferred beamforming matrix for pre-processing signals to be transmitted
to the UE.
The channel state information may include channel rank information for the
channels
available to the UE, the desired modulation and coding selection (MCS), and
associated
active set. The channel rank may indicate a number of spatial layers /
channels available for
communications with the UE.
[0136] At block 906, the coordination device may detect additional
network
system information. In some implementations, the additional network system
information
may include a characteristic of the UE. The characteristic of the UE may be
received
concurrently or separately from the channel state information. Characteristics
of the UE
which may be received include application(s) executing on the UE which may
require the
downlink data traffic, communication protocol or data protocol the UE intends
to use for the
downlink data traffic (e.g., HTTPS, FTP, IMS, VoIP, MPEG-DASH, etc.), mobility
of the
UE (e.g., Doppler data or other motion estimation), device type, operating
system, antenna
capabilities (e.g., number of receive antenna), power class or quality of
service indicators
such as delay and throughput specification. The additional network system
information may
32
CA 03116921 2021-04-16
WO 2020/096860 PCT/US2019/059196
include a characteristic of the RRU currently serving the UE. For example, the
number of
UEs currently being served by the RRU may be used to determine a load within
the service
area of the RRU. The additional network system information may include
characteristics of
other UEs. Characteristics of multiple UEs or RRUs may be aggregated to
generate a metric
for the network. For example, an average signal-to-noise ratio may be
generated for a
sampling of UEs.
[0137] At block 908, the coordination device may determine whether
dynamic
thresholds are used. The determination may be based on a configuration value
accessible by
the coordination device. In some implementations, the configuration value may
indicate
whether or not dynamic thresholds should be generated. In some
implementations, the
configuration value may be implemented as a look up table identifying
different threshold
techniques based on, for example, UE characteristics, channel state
information, time, date,
network conditions, etc. If the determination at block 908 is affirmative, at
block 910, the
coordination device may generate selection thresholds for selecting downlink
traffic mode
for the UE. The generation may be based on an average mobility of UEs within
the network
or within a service area of the RRU. The generation may be based on maximum or
mean
Eigen-value of channel matrices of UEs within the network. The generation may
be based on
a total number of antennas within the network. In MIMO systems, the number of
antennas
available may be much greater than the number of RRUs because each RRU may
include
multiple antennas.
[0138] Returning to block 908, if the coordination device determines
that
thresholds will not be dynamically generated, at block 912, static selection
thresholds are
obtained. The static selection thresholds may be obtained from a memory or
other
configuration data store accessible by the coordination device.
[0139] At block 914, using either the dynamic thresholds or static
thresholds, the
coordination device may identify a downlink data transmission mode for the UE.
The
assessment may compare one or more of the thresholds to specific values for
the UE or
network to identify a mode. The comparison may be specified in a memory or
other
configuration data store accessible by the coordination device. For example,
the modes may
be selected using a truth table whereby satisfaction of certain conditions
cause selection of a
specific mode. Table 1 provides an example of such a truth table. The truth
table may be
33
CA 03116921 2021-04-16
WO 2020/096860 PCT/US2019/059196
organized in priority such that the mode corresponding to the first set of
conditions met will
be used.
TABLE 1
Option Condition Mode
1 UE Mobility < mobility threshold Coordinated multipoint
--AND--
UE DL Channel Matrix Eigen-value Spread <
matrix threshold
2 UE Mobility > mobility threshold Macro diversity
--OR--
UE channel matrix Eigen spread < matrix
threshold
--OR--
UE count ¨ TX Antenna Count > density
threshold
3 Macro diversity , TRUE Best Server Mode
--AND ¨
Best effort traffic
4 True (default mode) Coordinated multipoint
[0140] In some implementations, the truth table may be generated using
machine
learning. For example, observed characteristics of the network and/or UE may
be provided as
inputs to a neural network trained using historical active set / mode
decisions. The neural
network may provide an output vector of including one or more values
indicating a predicted
active set, transmission mode, or transmission parameters (e.g., time,
frequency, power,
beamforming matrix, tone allocation, or channel rank.
[0141] At block 920, the coordination device may select the serving
nodes to
provide transmission service according to the transmission mode identified at
block 914.
[0142] The coordination device may perform the selection at block 920
using the
network system information detected at block 906. In some implementations, the
UE may
identify a neighbor active set of serving nodes. The neighbor active set of
serving nodes may
34
CA 03116921 2021-04-16
WO 2020/096860 PCT/US2019/059196
include nodes which the UE can detect (e.g., receive transmissions from). The
selection may
consider any serving nodes currently assigned to the UE along with the
neighboring nodes.
The coordination device may consider the load for the nodes, current and
anticipated location
of the UE in comparison to the nodes, or other detectable information. Serving
nodes may be
selected based on one or more of: (1) the link quality to one or more TRPs in
the current
active set deteriorates below a threshold; (2) there is one or more new TRPs
where the link
quality exceed a threshold; or (3) a redirection command is received from the
network to
redirect the UE such as to distribute load to a more balanced allocation
across the network.
[0085] As part of the selection, the coordination device may also
identify
scheduling information for the serving nodes. The scheduling information may
be selected to
reduce interference between downlink transmissions to the UE and other
downlink
transmissions. The interference reduction may be achieved by adjusting the one
or more of
transmission mode, time, frequency, power, beamforming matrix, tone
allocation, channel
rank, or direction of the transmission relative to other transmissions from
the serving node or
other serving nodes in proximity to a selected serving node.
[0143] At block 922, the coordination device may configure the network
for the
selected downlink transmission mode. The configuration of the network may
include
adjusting one or more transceivers at the UE or the RRU. The configuration may
also include
causing the UE to switch signal processing pipeline for received data
transmissions (e.g.,
enable coordinated multipoint decoding and disable coherent / non-coherent
combining). In
some implementations, the configuration may include transmitting a physical
downlink
control channel (PDCCH) message including at least a portion of the
configuration
information. The configuration information (e.g., active set and/or
transmission mode), may
be provided to the UE via another control channel message, radio resource
control signaling,
mobility management protocol, appended to identifiers of the RRUs / TRPs in
the active set,
or other messaging from the coordination device to the UE.
[0144] Having achieved a configuration of the network suited to the
network
conditions and UE conditions, the method 900 may end at block 990. However,
the UE may
be configured to periodically or aperiodically provide channel state
information reports. The
coordination device may repeat the method 900 to assess updated reports. In
some
implementations, the coordination device may identify a difference between an
updated
CA 03116921 2021-04-16
WO 2020/096860 PCT/US2019/059196
report and a previous report. If the difference does not meet a threshold, the
method 900 may
not expend the resources to re-assess the downlink traffic configuration for
the UE.
[0145] The method 900 describes how a network device (e.g., BBU) may
direct
the downlink traffic configuration for a UE.
[0146] Figure 10 is a flow diagram illustrating an example method of
dynamically configuring downlink data traffic modes for a user equipment in a
network from
the UE's perspective. The method 1000 may be performed in whole or in part
under control
of a coordination device such as a UE. The method 1-00 demonstrates features
for
identifying coordinated multipoint communication or an alternate mode for
downlink data
traffic to a UE. The identification includes providing accurate and updated
reports of
characteristics of the UE to the BBU and adjusting the UE based on an
identified downlink
traffic mode.
[0147] The method 1000 may begin at block 1002. At block 1004, the
coordination device may receive a first active set including one or more
serving nodes to
provide downlink data transmission service in a first mode to a UE. The first
active set and
identifier for the first mode may be received from one or more TRPs serving
the UE. The
first active set and/or the first mode may be identified by a BBU controlling
the RRU. The
first active set and/or the first mode may be identified by the BBU using the
method 900.
[0148] At block 1006, the coordination device may detect a
characteristic of the
UE. The characteristic of the UE may include channel state information. The
channel state
information may include channel quality indicators for one or more channels
available to the
UE. The channel state information may include precoding information such as a
preferred
channel matrix for processing signals received from an antenna of the UE. The
channel state
information may include a channel rank. Additional or alternative
characteristics of the UE
which may be received include application(s) executing on the UE which may
require the
downlink data traffic, communication protocol or data protocol the UE intends
to use for the
downlink data traffic (e.g., HTTPS, FTP, IMS, VoIP, MPEG-DASH, etc.), mobility
of the
UE (e.g., Doppler data or other motion estimation), device type, operating
system, antenna
capabilities (e.g., number of receive antenna), power class, or quality of
service.
[0149] At block 1014, the coordination device may transmit the channel
state
information and the characteristic to a BBU (e.g., base station). The channel
state
36
CA 03116921 2021-04-16
WO 2020/096860 PCT/US2019/059196
information may be provided using a channel state information report. The
additional
characteristic(s) may be provided as a part of the report or via a separate
message transmitted
by the coordination device.
[0150] At block 1015, the coordination device may receive a second
active set of
one or more serving nodes to provide the downlink data transmission service in
a second
mode. At this point in the method 1000, the UE is being asked to switch modes
from the first
mode to a second mode. The coordination device may first determine which mode
is to be
used for downlink data traffic based on the received message and then adjust
accordingly.
[0151] At block 1016, the coordination device may determine whether
the second
transmission mode is CoMP. The determination at block 1016 may include
comparing a
transmission mode identifier included in a message received from an RRU to a
predetermined value associated with CoMP. If the determination at block 1016
is negative, at
block 1018, the coordination device may configure (e.g., adjust) the user
equipment for
macro diversity downlink data transmissions. If the determination at block
1016 is
affirmative, at block 1010, the coordination device may configure (e.g.,
adjust) the user
equipment for coordinated multipoint downlink data transmissions.
[0152] After configuring the UE for the selected downlink data traffic
mode, at
block 1022, the coordination device may determine whether the UE is still
actively using the
downlink channel. The determination may be based on receipt or transmission a
message to
or from the UE. The determination may be based on execution status of an
application or the
operating system. For example, the operating system of the UE may include an
airplane
mode or a mode whereby all wireless communications are turned off. The
determination may
be based on a power state for the UE (e.g., powering down). If the UE is no
longer active, the
method 1000 may end at block 1090. If the UE is still active, the method 1000
may return to
block 1006 to detect and transmit updated characteristics to thereby receive
additional
downlink transmission configuration information selected based on the updated
characteristics.
User Equipment Assisted Communication Mode Determination
[0153] User equipment can determine a desired mode in which to receive
a
downlink data transmission. The desired mode can be either CoMP mode or the
alternative
37
CA 03116921 2021-04-16
WO 2020/096860 PCT/US2019/059196
downlink data transmission mode. Then the user equipment can send a request to
a network
system, such as a base station, to provide the downlink data transmission in
the desired mode.
The request can include desired active set data that identifies a desired
active set of one or
more serving nodes associated with the desired mode. The request can include
an identifier
for a desired transmission mode. The identifier may be a mode select bit
included in the
request, a message transmitted by the UE, or a value appended to one or more
of the
identifiers of the desired active set of one or more serving nodes. The
network system can
determine a mode of downlink data transmission to the user equipment based on
the request
and other data. This can contribute to the operation of a high data rate and
high reliability
wireless network.
[0154] The user equipment can determine the desired mode for all
antennas of the
user equipment. In some instances, the desired mode can be determined for a
particular
antenna or subset of antennas of the user equipment. Accordingly, in certain
instances, a
subset of antennas of a user equipment can receive first user data in CoMP
mode and a
different subset of the antennas of the same user equipment can receive second
user data in
the alternative downlink data transmission mode.
[0155] The user equipment can determine the desired mode of operation
based on
any suitable information available to the user equipment, such as any suitable
information
disclosed herein associated with mode determination. Such information can
include, for
example, mobility data, a network to user equipment channel matrix condition,
inference
data, metrics or other data associated with serving nodes of a current active
set, metrics or
other data associated with neighbor nodes, the like, or any suitable
combination thereof.
Examples of metrics or other data associated with nodes include received
signal strength
indicator, signal-to-noise ratio estimate, or error rate statistics.
Accordingly, based on
information available to the UE, a request can be generated by the UE to
receive data in a
desired mode of operation.
[0156] The request to operate in the desired mode can include
information to
indicate that the user equipment would like to change from one mode to
another. For
example, the request can include information indicating to toggle between
receiving data in
the CoMP mode and the alternative downlink data mode. In some instances,
active set data
of the request can indicate to operate in the same mode with a different set
of serving
38
CA 03116921 2021-04-16
WO 2020/096860 PCT/US2019/059196
node(s). As one example, the request can indicate to continue receiving data
in CoMP mode
from a different set of serving nodes than the current active set. As another
example, the
request can indicate to continue receiving data in the alternative downlink
data mode from a
different set of serving node(s) than the current active set.
[0157] Figure 11 illustrates representative communications and events
in a
heterogeneous MIMO network 1100 associated with a user equipment 1100
requesting to
receive downlink data in a desired mode. The communications and events of
Figure 11 are
associated with the user equipment 1110, a remote radio unit (RRU) 1120,
and/or a base
band unit (BBU) 1130 of the heterogeneous MIMO network 1100. In the
communications
and events of Figure 11, the UE 1110 selects a desired mode to receive a
downlink data
transmission and the BBU 1130 generates a downlink schedule to schedule
downlink data
transmissions from one or more serving nodes to the UE 1110.
[0158] In event 1150 of Figure 11, the UE 1110 detects conditions. The
UE 1110
can gather any suitable information from which to determine a desired mode to
receive a
downlink data transmission. The UE 1110 can detect any suitable information
disclosed
herein for mode determination. The UE 1110 selects a desired mode of receiving
downlink
data transmissions based on the gathered information. This determination can
be based on
any suitable principles and advantages disclosed herein.
[0159] The UE 1110 stores and updates an active set of one or more
serving
nodes that provide wireless transmission services to the UE 1110. Active set
data is provided
by a network system that includes the RRU 1120 and the BBU 1130. The UE 1110
also
stores and updates a neighbor set of one or more serving nodes that are
available to provide
wireless transmission services to the UE 1110 and are not included in the
active set. The
UE 1110 may also store scheduling information such as the transmission mode or
other
parameters for transmissions to or from the UE 1110.
[0160] The UE 1110 generates a requested downlink schedule at event
1152. The
requested downlink schedule includes desired active set data identifying one
or more serving
nodes from which the UE 1110 requests to receive downlink wireless
transmission services.
The desired active set data can include one or more serving nodes from the
active set and/or
one or more serving nodes from the neighbor set. The desired active set data
is based on the
39
CA 03116921 2021-04-16
WO 2020/096860 PCT/US2019/059196
determination of the desired mode by the UE 1110. The schedule may include
information
identifying a desired transmission mode.
[0161] In event 1154, the UE 1110 and the RRU 1120 establish a
wireless
connection. This can include providing a UE identifier and a requested
downlink schedule.
The RRU 1120 and the BBU 1130 communicate at event 1156. The downlink schedule
is
provided from the RRU 1120 to the BBU 1130. The RRU 1120 can also provide a UE
identifier and an RRU identifier to the BBU 1130.
[0162] The BBU 1130 includes a scheduler that generates a downlink
schedule at
event 1158. BBU 1130 can receive information from a plurality of UEs and take
into
account more information than available to a single UE in determining the
downlink data
transmission mode to the UE 1110. Accordingly, it can be advantageous for a
network
system to determine the downlink data transmission mode to the UE 1110 even if
the
UE 1110 requests to receive downlink data in a particular mode. The network
system may
additionally or alternatively identify an active set of service nodes for data
transmissions for
the UE 1110.
[0163] The serving node schedule can be determined based on a request
from the
UE 1110 to receive downlink data in a desired mode and additional network
system
information. The additional network system information can include, for
example, one or
more of system load information such as load information for coordinated
multipoint
resources, data indicating a mobility state of the UE 1110, a spatial channel
condition of a
channel associated with the UE 1110, one or more characteristics of the UE
1110 (e.g., an
application type to utilize the transmission service, a protocol to utilize
over the transmission
service, or a device type for the UE 1110), one or more characteristics of one
or more UEs
other than the UE 1110, one or more conditions of one or more UEs other than
the UE 1110,
one or more behaviors of one or more UEs other than the UE 1110, the like, or
any suitable
combination thereof.
[0164] Based on the request and the additional network system
information, the
scheduler of the BBU 1130 can (1) grant the request, (2) continue to schedule
downlink data
transmission to the UE 1110 without changing the mode of operation or the
active set for the
UE 1110, or (3) cause the way the UE 1110 is being served to change in a way
that is
different than requested by the UE 1110.
CA 03116921 2021-04-16
WO 2020/096860 PCT/US2019/059196
[0165] The request can be granted when the additional network system
information is consistent with providing downlink data transmission to the UE
1110 in the
desired mode. To grant the request, the scheduler can update the active set
for the UE 1110
to match the desired active set in the request. Then the scheduler can cause
downlink data
transmission to the UE 1110 in the desired mode from the one or more serving
nodes of the
desired active set.
[0166] In some instances, the additional network system information
can indicate
that the active set and current mode of operation can provide better overall
network services
than granting the request. Accordingly, in such instances, the scheduler can
continue to route
downlink data to the UE 1110 without changing the mode of operation or the
active set for
the UE 1110.
[0167] The scheduler can cause the way the UE 1110 is being served to
change
differently than requested by the UE 1110 based on the request and the
additional network
system information. For example, the scheduler can determine to update the
active set for
the UE 1110 in a different way than requested by the UE based on the request
and the
additional network system information. According to some other instances, the
scheduler
can cause a power level of a downlink data transmission to the UE 1110 to be
adjusted based
on the request and the additional network information. Any other parameter of
the
transmission from the network system, such as frequency and/or time, can be
similarly
adjusted.
[0168] Referring back to Figure 11, the BBU 1130 can provide downlink
scheduling parameters to the RRU 1120 in event 1160. This can include
providing updated
active set data for the UE 1110. Any other suitable scheduling information can
be provided
to the RRU 1120. In some instances where downlink scheduling parameters are
unchanged,
a confirmation that the downlink scheduling parameters are unchanged and be
sent in place
of the downlink scheduling parameters. Although Figure 11 illustrates the same
RRU 1120
receiving a request downlink schedule from the UE 1110 and providing a
downlink schedule
to the UE 1110, different RRUs can facilitate communication between the UE
1110 and the
BBU 1130 for different communications as suitable.
[0169] As shown in Figure 11, the RRU 1120 can provide downlink
parameters
to the UE 1110 in event 1162. This can include providing the UE 1110 with
updated active
41
CA 03116921 2021-04-16
WO 2020/096860 PCT/US2019/059196
set data and/or one or more other parameters to configure the UE 1110 for
receiving
downlink data from the network based on the downlink data transmission
schedule
determined by the scheduler. In some instances where downlink UE parameters
are
unchanged, a confirmation that the downlink UE parameters are unchanged and be
sent in
place of the downlink UE parameters.
[0170] The UE 1110 can adjust a receiver of the UE 1110 for receiving
data for
the selected downlink transmission mode in event 1164. The receiver of the UE
1110 can be
adjusted for processing downlink data received in the selected mode from one
or more
serving nodes in the active set provided by the network system. The receiver
of the UE 1110
can be adjusted for receiving signals having a different power, direction,
timing, frequency,
or any suitable combination thereof. This can involve adjusting any suitable
circuitry of the
receiver. The receiver of the UE 1110 can be included in a transceiver.
[0171] In event 1166, a transmitter of the RRU 1120 can be adjusted
for
transmitting downlink data in the selected mode to the UE 1110. This can
involve adjusting
one or more of a transmission power, direction, timing, or frequency of a
downlink data
transmission from the RRU 1120. Adjusting the transmitter can involve
adjusting any
suitable circuitry of the transmitter. The transmitter can be included in a
transceiver of the
RRU 1120.
[0172] The UE 1110 and the RRU 1120 wirelessly exchange downlink data
and
uplink data in event 1168. During this exchange of data, the UE 1110 can
provide updated
data to the BBU 1130 including an updated requested downlink schedule request
and
additional data associated with the UE from which to determine the selected
mode of
downlink data transmission. Accordingly, the scheduler of the BBU 1130 can
dynamically
select the mode of downlink data traffic in the heterogeneous MIMO network
1100.
[0173] As discussed above, a variety of different UEs can wirelessly
communicate with serving nodes in a heterogeneous MIMO network. As example UE
will
be discussed with reference to Figure 12.
[0174] Figure 12 is a schematic block diagram of an example UE 1200
according
to an embodiment. The UE 1200 is configured for wirelessly communicating with
a base
station in a heterogeneous MIMO network. As illustrated, the UE 1200 includes
a
processor 1240, a user interface 1245, a data store 1250, a beamformer 1255,
antennas 1262
42
CA 03116921 2021-04-16
WO 2020/096860 PCT/US2019/059196
and 1264, a transceiver 1265, a motion detector 1270, a signal quality
analyzer 1275, and an
active set selector 1280. Some other UEs can include additional elements
and/or a subset of
the elements illustrated in Figure 12.
[0175] The UE 1200 includes a plurality of antennas 1262 and 1264. Any
suitable number of antennas can be included for wireless communication in CoMP
mode
and/or the alternative downlink data transmission mode. The UE 1200 can
include one or
more arrays of antennas. A radio frequency (RF) front end 1260 can process RF
signals
received via the antennas 1262 and 1264. The RF front end can also provide RF
signals to
the antennas 1262 and 1264 for transmission. The transceiver 1265 includes a
transmitter
and a receiver. The transceiver 1265 can provide processing for transmitting
and receiving
RF signals associated with the antennas 1262 and 1264.
[0176] The processor 1240 is in communication with the transceiver
1265. The
processor 1240 is implemented by physical hardware arranged to perform
specific operations
to implement functionality related to determining a desired mode and causing a
request
related to the desired mode to be transmitted from the UE 1200. The processor
1240 can
determine a desired mode in which to receive downlink data and generated a
request to
receive downlink data in the desired mode in accordance with any suitable
principles and
advantages disclosed herein. The processor 1240 can cause active set and
neighbor set data
to be stored and updated. The processor 1240 can perform any other suitable
processing for
the UE 1200.
[0177] The processor 1240 can be in communication with the motion
detector 1270 and the signal quality analyzer 1275. Accordingly, the processor
1240 can
receive and process information associated with conditions of the UE 1200. The
motion
detector 1270 can include any suitable hardware arranged to detect mobility
information
associated with the UE 1200. The signal quality analyzer 1275 can analyze the
quality of
signals received and/or transmitted by the antennas 1262 and 1264. This can
provide
information associated with a spatial channel condition of the UE 1200. The
information
associated with conditions of the UE 1200 can be provided to the processor
1240 for
determining a desired mode in which to receive downlink data. In some
instances, some or
all of the functionality of the motion detector 1270 and/or the signal quality
analyzer can be
implemented by the processor 1240.
43
CA 03116921 2021-04-16
WO 2020/096860 PCT/US2019/059196
[0178] The active set selector 1280 can identify a desired active set
of one or
more serving nodes associated with the desired mode determined by the
processor 1240. The
active set selector 1280 can select the desired active set based on data
associated with one or
more of: one or more serving nodes in the active set, one or more serving
nodes in the
neighbor set, mobility data associated with the UE 1200, a spatial channel
condition
associated with the UE 1200, or one or more characteristics of the UE 1200.
Desired active
set data can be provided with the request to operate in the desired mode. The
active set
selector 1280 can be implemented by dedicated circuitry and/or circuitry of
the
processor 1240.
[0179] The beamformer 1255 can perform any suitable beamforming
functionality for the UE 1200. The beamformer 1255 can set and/or adjust one
or more
parameters associated with receiving and/or transmitting signals associated
with the
antennas 1262 and 1264 of the UE 1200. The beamformer 1255 can be implemented
by
dedicated circuitry and/or circuitry of the processor 1240.
[0180] The UE 1240 includes a data store 1250. The data store 1250 can
store
instructions that can be executed by the processor 1240 to implement the
features described.
The data store 1250 can store active set data and neighbor set data for the UE
1200. The data
store 1250 can store any other suitable data for the UE 1200. The data store
1250 can
include any suitable memory elements arranged to store data.
[0181] Several elements included in the UE 1200 may be coupled by a
bus 1290.
The bus 1290 can be a data bus, communication bus, other bus, or any suitable
combination
thereof to enable the various components of the UE 1200 to exchange
information.
[0182] As illustrated, the UE 1200 also includes a user interface
1245. The user
interface 1245 can be any suitable user interface, such as a display and/or an
audio
component. In some instances, the user interface 1245 can include one or more
of touch
screen capabilities, a button, a knob, a switch, or a slider.
[0183] Figure 13 is a flow diagram of an example process 1300 of
requesting a
selected communication mode in which to receive data at an antenna of a UE
according to an
embodiment. The process 1300 can be performed by any suitable UE, such as any
suitable
UE disclosed herein. The process 1300 illustrates aspects of a UE generating
and sending a
request to receive downlink data in a desired mode of operation. The process
1300 can be
44
CA 03116921 2021-04-16
WO 2020/096860 PCT/US2019/059196
performed in each of a plurality of UEs that are concurrently wirelessly
communicating with
the same base station.
[0184] The process 1300 begins at block 1302. At block 1304, active
set data
transmitted from a base station is received by a UE. The active set data
identifies a set of one
or more serving nodes to provide downlink data to the UE. The UE stores the
active set data
and updates the active set data in response to receiving updated active set
data from the base
station. The active set data can be received by the processor 1240 and stored
in the data
store 1250 of the UE 1200 of Figure 12, for example.
[0185] The UE detects conditions at block 1306. Detecting conditions
associated
with the UE can provide useful information from which the UE generates a
request to receive
downlink data in a selected mode. The detected conditions can include any
suitable
conditions and/or metrics disclosed herein. For example, the UE can detect a
mobility state
of the UE and/or a spatial channel condition of the UE. One or more conditions
can be
detected using the motion detector 1270 and/or the signal quality analyzer
1275 of the
UE 1200, for example.
[0186] The UE determines a selected mode of wirelessly receiving data
using an
antenna element. The selected mode is either a coordinated multipoint mode or
an alternate
downlink data transmission mode. The selected mode can be determined in
accordance with
any suitable principles and advantages disclosed herein. A processor, such as
the
processor 1240 of the UE 1200, can be used to determine the selected mode. The
selected
mode can be for some or all of the antennas of the UE. At decision block 1308,
the UE can
determine whether conditions are suitable for CoMP. If conditions are suitable
for CoMP
mode, CoMP mode is selected as the desired mode at block 1310. Alternatively,
if one or
more conditions are unsuitable for CoMP mode, an alternative downlink data
transmission
mode is selected as the desired mode at block 1312. The alternative downlink
data
transmission mode can be any suitable alternative downlink data transmission
mode
disclosed herein.
[0187] The determination of the selected mode can be based on the
conditions
detected at block 1306. For instance, the selected mode can be determined
based on a
mobility state of the UE and/or a spatial channel condition of the UE. A
threshold level of
the mobility state associated with operating in the CoMP mode can be
determined based on
CA 03116921 2021-04-16
WO 2020/096860 PCT/US2019/059196
the conditions detected at block 1306. Alternatively or additionally, a
threshold level of the
spatial channel state condition associated with operating in the CoMP mode can
be
determined based on the conditions detected at block 1306.
[0188] In some implementations, the UE may additionally or
alternatively
identify a desired active set of serving nodes for wireles sly receiving data.
The desired
serving nodes may be identified based on the conditions detected at block
1306. For example,
the UE may detect a signal from a TRP and based on received-signal-strength or
other metric
for one or more signals from the TRP, determine the quality for transmissions
received from
the TRP.
[0189] At block 1314, the UE can send a request via at least one
antenna to
receive data in the selected mode. The processor of the UE can cause the
transmission via at
least one antenna of the UE. For instance, in the UE 1200, the processor 1240
can cause
transmission of the request using antenna 1262. The request can include a
desired active set.
The request can include information identifying the selected mode, such as one
or more
mode select bits. The process ends at block 1316.
[0190] Some or all of the process 1300 can be performed repeatedly
while the UE
is active. Accordingly, the UE can provide requests to receive data in a
desired mode based
on up to date conditions detected by the UE. The request can be updated
periodically and/or
dynamically. As one example, a UE can be located in a crowded football stadium
and
request to receive data in the CoMP data transmission mode because of, for
instance, a higher
number of TRPs that are likely available in the stadium. After the UE leaves
the football
stadium and is located in a residential area, the UE can request to receive
data in an
alternative downlink mode because the TRPs may be more sparsely distributed in
the
residential area than in the stadium. As another example, the UE can receive
data in the
CoMP mode while the UE has relatively low mobility. In response to a
significant increase
in mobility, such as being located in a vehicle on a highway, the UE can
request to receive
data in the alternative downlink data transmission mode.
[0191] Figure 14 is a flow diagram of an example process 1400 of
controlling a
downlink data transmission mode to a UE based on a request from the UE
according to an
embodiment. The process 1400 can be performed by any suitable network system,
such as
any suitable base station. For instance, some or all of the process 1400 can
be performed by
46
CA 03116921 2021-04-16
WO 2020/096860 PCT/US2019/059196
the baseband unit 510 of Figure 5 and/or the baseband unit 820 of Figure 8.
The
process 1400 illustrates aspects of a network system determining a downlink
data
transmission mode based on a request from a UE to receive data in particular
mode and
additional network system information.
[0192] The process 1400 begins at block 1402. At block 1404, a
scheduler of the
network system receives network system information. The network system
information can
be received via one or more antennas of a base station. The network system
information can
be received from a plurality of UEs. Accordingly, the scheduler can have
access to
additional data that is unavailable to a UE requesting to receive downlink
date in the
particular mode. The network system information can include any suitable
information from
which a network scheduler determines a mode of downlink data transmission to a
UE
disclosed herein. The network system information can include mobility state
information for
one or more UEs, spatial channel state conditions for one or more UEs, system
load
information, characteristics of one or more UEs, the like, or any suitable
combination
thereof. The scheduler receives a request from a UE to receive downlink data
in a particular
mode at block 1406. The request can include desired active set data and/or a
one or more
mode select bits.
[0193] Based on the request and additional network system information,
the
scheduler determines a downlink data transmission mode for wirelessly
transmitting data to a
UE. The scheduler can also determine the active set for a UE and/or a subset
of antennas of a
UE. The determined downlink data transmission mode is either CoMP mode or an
alternative downlink data transmission mode. The alternative downlink data
transmission
mode is a non-CoMP mode. The alternative downlink data transmission mode can
be, for
example, synchronized transmission across multiple network nodes for coherent
combining,
transmissions across multiple network nodes for non-coherent combining, or
individual
transmission from a selected best serving node.
[0194] Referring to Figure 14, at decision block 1408, the scheduler
determines
whether to grant the request. The request can be granted or denied based on
any suitable
information and/or methods disclosed herein. If the request is granted at
block 1408, the
particular mode identified in the request is set as the downlink data
transmission mode to the
UE at block 1410. Alternatively, if the request is denied at block 1408, the
scheduler can
47
CA 03116921 2021-04-16
WO 2020/096860 PCT/US2019/059196
determine whether to adjust a downlink data transmission parameter based on
the request at
decision block 1412. In response to determining to adjust the downlink data
parameter at
block 1412, the scheduler can cause a downlink data transmission parameter to
be adjusted at
block 1414. One or more of the following downlink data transmission parameters
can be
adjusted: power, time, frequency, or direction. Alternatively or additionally,
active set data
can be adjusted without granting the request.
[0195] At block 1416, active set data is transmitted to the UE. The
active set data
can include any suitable data that identifies an active set. The active set
data can identify the
active set for the UE. In some instances, the active set data can identify
changes to the active
set for the UE. According to certain instances, the active set data can
indicate that the active
set for the UE is unchanged. In response to the particular mode being set as
the downlink
data transmission mode at block 1410, the active set data transmitted at block
1416 can
identify the desired active set provided by the UE as the active set for the
UE. In response to
the request being denied at block 1408 and the determination not to adjust
downlink data
transmission at block 1412, the active set data transmitted at block 1416 can
indicate that the
active set is unchanged. In response to the request being denied at block 1408
and the
determination to adjust downlink data transmission at block 1412, the active
set data
transmitted at block 1416 can indicate that the active set is unchanged in
some instances and
a change to the active set in some other instances.
[0196] At block 1418, downlink data is transmitted to the UE in the
downlink
data transmission mode determined based on the request and additional network
system
information. The UE receives the downlink data from the one or more serving
nodes in the
active set.
[0197] Some or all of the process 1400 can be performed repeatedly.
Accordingly, the scheduler can set the downlink data transmission mode to the
UE based on
an up to date request and up to date network system data. The process 1400 can
be
performed for each UE in communication with a network system. The process 1400
can be
performed for two or more different subsets of one or more antennas of the
same UE.
48
CA 03116921 2021-04-16
WO 2020/096860 PCT/US2019/059196
Further Embodiments
[0198] Additional embodiments are described with reference to Figures
15
to 16B. These figures illustrate examples of a heterogeneous MIMO network
serving UEs in
different modes with active set allocation.
[0199] Figure 15 is a diagram illustrating allocation of active sets
and
transmission modes in a heterogeneous MIMO environment 1500. This figure
illustrates that
different UEs can be served in different downlink data transmission modes. As
illustrated,
the heterogeneous MIMO environment 1500 includes four RRUs 1502, 1504, 1506,
and 1508 and three UEs 1512, 1514, and 1516.
[0200] The first UE 1512 is static. Thus, the first UE 1512 has low
mobility. The
first UE 1512 is also near several RRUs 1502, 1504, and 1506. Accordingly, a
network
system can schedule downlink data transmissions to the first UE 1512 in CoMP
mode. The
network system can identify RRUs 1502, 1504, and 1506 as the active set of
serving nodes
for the first UE 1502 in the CoMP mode.
[0201] The second UE 1514 is near a single RRU 1508. Without multiple
serving
nodes available, the network system can schedule downlink data transmissions
to the second
UE 1514 in an alternative downlink data transmission mode, such as best server
mode (e.g.,
best server selection SIMO, best server selection SU-MIMO, best server
selection MU-
MIMO). The network system can identify RRU 1508 as the active set for the
second
UE 1508 in the best server mode.
[0202] The third UE 1516 is moving at 30 kilometers per hour. Thus,
the third
UE 1516 has relatively high mobility. The first UE 1515 is also near RRUs 1502
and 1504.
With relatively high mobility and more than one serving node available, the
network system
can schedule downlink data transmissions to the third UE 1516 in an
alternative downlink
data transmission mode, such as SFN mode. The network system can identify RRUs
1502
and 1504 as the active set of serving nodes for the third UE 1506 in the SFN
mode.
[0203] Figures 16A and 16B are diagrams illustrating different
allocations of
active sets and transmission modes in a heterogeneous MIMO environment 1600
with
dynamic network demands. These figures illustrate that the active set and/or
downlink data
transmission mode can change due to changing network conditions in a
heterogeneous
MIMO environment. For instance, the active set and downlink data transmission
mode can
49
CA 03116921 2021-04-16
WO 2020/096860 PCT/US2019/059196
change as a function of active UEs in the heterogeneous MIMO environment 1600.
Figures 16A and 16B provide an example in which an active set for a UE can be
determined
based on network information associated with one or more other UEs.
[0204] In Figure 16A, there is a single UE 1612 in the heterogeneous
MIMO
environment 1600. As illustrated, the network can schedule downlink data to
the UE 1612 in
a best server mode with an active set of RRU 1606. The RRUs 1602, 1604, and
1608 can be
unused in this case.
[0205] Additional UEs can enter the heterogeneous MIMO environment
1600.
As shown in Figure 16B, two additional active UEs 1614 and 1616 are present in
the
heterogeneous MIMO environment 1600 relative to Figure 16A. The UEs 1614 and
1616 are
both relatively close to the UE 1612 and the RRU 1606. The network can
schedule downlink
data to each of the UEs 1612, 1614, and 1616 in CoMP mode an active set of
RRUs 1602, 1604, and 1608. In Figure 16A, the active set for the UE 1612
included
RRU 1606. However, upon assessment of the changing network conditions (e.g.,
the
additional presence of UE 1614 and UE 1616 and associated wireless
communication desires
of these UEs), the environment 1600 may be reconfigured to allocate the
resources to serve
the UE 1612, the UE 1614, and the UE 1616. The reconfiguration may include
assigning a
new active set of one or more serving nodes such as for UE 1612. Alternatively
or
additionally, the reconfiguration can include changing a downlink data
transmission mode
such as for UE 1612 from BSM in Figure 16A to CoMP in Figure 16B. The
configuration in
Figure 16B can provide improved spatial channel conditions relative to the
case where
RRU 1606 alone is used to separate beams for three concurrent UEs.
[0206] Although the embodiments discussed herein provide various
example of
operating in the CoMP mode or an alternative downlink data transmission mode,
there are
numerous use cases where one or another is preferred. Some additional examples
will briefly
be discussed.
[0207] CoMP mode can be preferred for high definition video streaming.
CoMP
mode can be preferred for downlink data transmission associated with virtual
and/or
augmented reality. CoMP mode can be preferred for relatively large file
transfers. When a
UE is in mobility, best server mode can be preferred for high definition video
streaming,
virtual and/or augmented reality data, and relatively large file transfers.
CA 03116921 2021-04-16
WO 2020/096860 PCT/US2019/059196
[0208] A soft combining mode can be preferred for relatively low
latency high
quality audio. Soft combining mode can be preferred for voice calling and
video telephony.
[0209] A non-coherent combining mode can be preferred for relatively
low
latency robotic control. For industrial automation control, a non-coherent
combining mode
can be preferred. Advanced driver assistance systems (ADAS) can prefer a non-
coherent
combining mode.
Terminology, Applications, and Conclusion
[0210] Depending on the embodiment, certain acts, events, or functions
of any of
the processes or algorithms described herein can be performed in a different
sequence, can be
added, merged, or left out altogether (e.g., not all described operations or
events are
necessary for the practice of the algorithm). Moreover, in certain
embodiments, operations,
or events can be performed concurrently, e.g., through multi-threaded
processing, interrupt
processing, or multiple processors or processor cores or on other parallel
architectures, rather
than sequentially.
[0211] Conditional language used herein, such as, among others, "can,"
"could,"
"might," "may," "e.g.," and the like, unless specifically stated otherwise, or
otherwise
understood within the context as used, is generally intended to convey that
certain
embodiments include, while other embodiments do not include, certain features,
elements,
and/or steps. Thus, such conditional language is not generally intended to
imply that features,
elements, and/or steps are in any way required for one or more embodiments or
that one or
more embodiments necessarily include logic for deciding, with or without other
input or
prompting, whether these features, elements, and/or steps are included or are
to be performed
in any particular embodiment. The terms "comprising," "including," "having,"
and the like
are synonymous and are used inclusively, in an open-ended fashion, and do not
exclude
additional elements, features, acts, operations, and so forth. Additionally,
the words "herein,"
"above," "below," and words of similar import, when used in this application,
shall refer to
this application as a whole and not to any particular portions of this
application. Where the
context permits, words in the above Detailed Description of Certain
Embodiments using the
singular or plural may also include the plural or singular, respectively.
Also, the term "or" is
51
CA 03116921 2021-04-16
WO 2020/096860 PCT/US2019/059196
used in its inclusive sense (and not in its exclusive sense) so that when
used, for example, to
connect a list of elements, the term "or" means one, some, or all of the
elements in the list.
[0212] Disjunctive language such as the phrase "at least one of X, Y,
Z," unless
specifically stated otherwise, is otherwise understood with the context as
used in general to
present that an item, term, etc., may be either X, Y, or Z, or any combination
thereof (e.g., X,
Y, and/or Z). Thus, such disjunctive language is not generally intended to,
and should not,
imply that certain embodiments require at least one of X, at least one of Y,
or at least one of
Z to each be present.
[0213] Unless otherwise explicitly stated, articles such as "a" or
"an" should
generally be interpreted to include one or more described items. Accordingly,
phrases such as
"a device configured to" are intended to include one or more recited devices.
Such one or
more recited devices can also be collectively configured to carry out the
stated recitations.
For example, "a processor configured to carry out recitations A, B and C" can
include a first
processor configured to carry out recitation A working in conjunction with a
second
processor configured to carry out recitations B and C.
[0214] The word "coupled," as generally used herein, refers to two or
more
elements that may be either directly coupled to each other, or coupled by way
of one or more
intermediate elements. Likewise, the word "connected," as generally used
herein, refers to
two or more elements that may be either directly connected, or connected by
way of one or
more intermediate elements.
[0215] As used herein, the terms "determine" or "determining"
encompass a wide
variety of actions. For example, "determining" may include calculating,
computing,
processing, deriving, generating, obtaining, looking up (e.g., looking up in a
table, a database
or another data structure), ascertaining and the like via a hardware element
without user
intervention. Also, "determining" may include receiving (e.g., receiving
information),
accessing (e.g., accessing data in a memory) and the like via a hardware
element without user
intervention. Also, "determining" may include resolving, selecting, choosing,
establishing,
and the like via a hardware element without user intervention.
[0216] As used herein, the terms "provide" or "providing" encompass a
wide
variety of actions. For example, "providing" may include storing a value in a
location of a
storage device for subsequent retrieval, transmitting a value directly to the
recipient via at
52
CA 03116921 2021-04-16
WO 2020/096860 PCT/US2019/059196
least one wired or wireless communication medium, transmitting or storing a
reference to a
value, and the like. "Providing" may also include encoding, decoding,
encrypting,
decrypting, validating, verifying, and the like via a hardware element.
[0217] As used herein, the term "message" encompasses a wide variety
of
formats for communicating (e.g., transmitting or receiving) information. A
message may
include a machine readable aggregation of information such as an XML document,
fixed
field message, comma separated message, or the like. A message may, in some
implementations, include a signal utilized to transmit one or more
representations of the
information. While recited in the singular, it will be understood that a
message may be
composed, transmitted, stored, received, etc. in multiple parts.
[0218] As used herein a "user interface" (also referred to as an
interactive user
interface, a graphical user interface or a UI) may refer to a network based
interface including
data fields and/or other controls for receiving input signals or providing
electronic
information and/or for providing information to the user in response to any
received input
signals. A UI may be implemented in whole or in part using technologies such
as hyper-text
mark-up language (HTML), Flash, Java, .net, web services, and rich site
summary (RSS). In
some implementations, a UI may be included in a stand-alone client (for
example, thick
client, fat client) configured to communicate (e.g., send or receive data) in
accordance with
one or more of the aspects described.
[0219] As used herein a "transmit-receive point" (TRP) (which can
alternatively
be referred to as a transmission reception point) may refer to a transceiver
device or one
transceiver element included in a device. When included as a transceiver
element, the device
may include multiple TRPs. The TRP may include one or more antennas which are
coupled
to signal processing circuitry. The signal processing circuitry may be
included in the device.
The TRP may include additional elements to facilitate transmission or receipt
of wireless
signals for one or more UEs. Example of such elements may include a power
source,
amplifier, digital-to-analog converter, analog-to-digital converter, or the
like. When a TRP is
allocated, such as by a BBU, to provide service to a UE, the TRP may be said
to be a
"serving node" for the UE.
[0220] As used herein a "remote radio unit" (RRU) may refer to a
device for
controlling and coordinating transmission and receipt of wireless signals for
one or more
53
CA 03116921 2021-04-16
WO 2020/096860 PCT/US2019/059196
UEs. An RRU may include or be coupled with one or more TRPs. The RRU may
receive
signals from the TRP and include the signal processing circuitry. The signal
processing
circuitry may be selectively operated to facilitate processing of signals
associated with
different TRPs.
[0221] While the above detailed description has shown, described, and
pointed
out novel features as applied to various embodiments, it can be understood
that various
omissions, substitutions, and changes in the form and details of the devices
or algorithms
illustrated can be made without departing from the spirit of the disclosure.
For example,
circuit blocks and/or method blocks described herein may be deleted, moved,
added,
subdivided, combined, arranged in a different order, and/or modified. Each of
these blocks
may be implemented in a variety of different ways. Any portion of any of the
methods
disclosed herein can be performed in association with specific instructions
stored on a
non-transitory computer readable storage medium being executed by one or more
processors.
As can be recognized, certain embodiments described herein can be embodied
within a form
that does not provide all of the features and benefits set forth herein, as
some features can be
used or practiced separately from others. The scope of certain embodiments
disclosed herein
is indicated by the appended claims rather than by the foregoing description.
All changes
which come within the meaning and range of equivalency of the claims are to be
embraced
within their scope.
54
