Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
Application no. CA2,931,856
Agent ref: 223-005CAP
Amendment dated 2018/07/10
SYSTEM AND METHOD FOR WIRELESS USER EQUIPMENT ACCESS
TECHNICAL FIELD
[0001] The following relates generally to wireless communication system
operation and spectrum
access and more specifically to the configuration of user equipment access to
system radio
frequency resources.
BACKGROUND
[0002] Specific radio frequency bands are set aside for wireless cellular
communications by
spectrum regulatory authorities (such as the Federal Communications Commission
in the United
States of America) to ensure the reliable operation of cellular communication
systems, and are
referred to as cellular bands. The term 'spectrum' is commonly used to refer
to the aggregate
bands that are assigned to the cellular communication network, also referred
to as the cellular
communication system, in any given jurisdiction. Another analogous phrase to
spectrum is radio
frequency resources.
[0003] Cellular bands can be contiguous or non-contiguous and are typically
divided into sub-
bands, which again can be contiguous or non-contiguous, that are licensed to
mobile network
operators. A mobile network operator thus deploys the network infrastructure
of a cellular
communication system, typically comprising a Radio Access Network (RAN) and a
Core Network
(CN), upon obtaining a spectrum utilization license, i.e. a license to use a
particular cellular band
or sub-band. Connection of User Equipment (UE) to system radio Access Points
(AP) of the
network infrastructure is facilitated by a wireless radio air interface,
referred to as the Radio
Access Technologies (RAT), which utilizes a specific amount of spectrum
commonly measured
by the transmission bandwidth.
[0004] RATs are characterized by the required transmission bandwidth,
transmission frame
duration, frequency reuse factor between system radio APs, user multiple
access scheme,
modulation and coding configurations along with the transmission and reception
protocols. Due
to the limited amount of spectrum available for cellular systems, RATs are
typically designed with
the objective of enabling maximal spectrum reuse at all system radio APs while
having the highest
possible spectral efficiency.
[0005] In terms of RAT support, UE broadly fall into one of two categories:
Single Mode User
Equipment (SMUE), capable of utilizing a single RAT only, and Multimode User
Equipment
(MMUE), capable of utilizing multiple RATs. Multiple RATs are primarily
deployed at system radio
APs in cellular communication systems to accommodate variations in the
capabilities of UE and
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CA 2931856 2018-07-10
Application no. CA2,931,856
Agent ref: 223-005CAP
Amendment dated 2018/07/10
maintain connectivity of SMUE. Each system radio AP could support one or more
RATs and
available bands or sub-bands are generally partitioned between RATs when
deploying multiple
RATs at system radio APs covering the same geographical areas. MMUE also
support multiple
RATs to maintain UE connectivity when connecting to system radio APs
supporting a single RAT
or multiple RATs that are inferior to the highest performing RAT supported by
the MMUE.
[0006] When connecting to system radio APs, UE are typically configured to
utilize a single RAT
only at any time. Such a mode of operation is referred to herein as Single-
Mode Access (SMA).
MMUE are thus limited under SMA to utilizing a single RAT even when connecting
to system radio
APs deploying multiple RATs. When connecting to system radio APs deploying
multiple RATs
under the restriction of SMA, MMUE are typically configured to utilize the
highest performing RAT
jointly supported by MMUE and the connecting system radio APs, referred to as
the primary mode
of operation, and MMUE configuration is typically capable of adapting the
utilized RAT as MMUE
connect to different system radio APs as well as when the connectivity
requirements of user
applications change. Nevertheless, configuring MMUE to utilize a single RAT
only when
connecting to system radio APs deploying multiple RATs can result in the
suboptimal utilization
of system radiofrequency resources, MMUE capabilities and the capabilities of
system radio APs.
[0007] When connecting system radio APs utilizing a single RAT over multiple
bands, UE may
simultaneously utilize (i) all bands jointly supported by UE and connecting
system radio APs; or
(ii) a subset of bands jointly supported by UE and connecting system radio
APs. In the latter case,
UE may not utilize all bands jointly supported by UE and connecting system
radio APs for various
reasons that include, but are not limited to, connectivity requirements of
user applications that
may not be fulfilled at certain bands or are better fulfilled by other bands,
energy efficiency
considerations and UE hardware or processing limitations. Traffic split
mechanisms include, but
are not limited to, sequential and weighted traffic split. Under sequential
traffic split, traffic demand
is steered at a designated band and traffic demand exceeding the capacity of
the designated
band is steered at another designated band and so on. On the other hand,
weighted traffic split
divides traffic between bands based on band capacity, such that bands
providing equal capacity
would carry equal amounts of traffic.
SUMMARY
[0008] Multimode User Equipment (MMUE) connecting to system radio Access
Points (APs)
deploying multiple Radio Access Technologies (RATs) are configured to
simultaneously utilize all
or a subset of RATs jointly supported by MMUE and connecting system radio APs
in a mode of
operation referred to herein as Multimode Access (MMA).
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CA 2931856 2018-07-10
Application no. CA2,931,856
Agent ref: 223-005CAP
Amendment dated 2018/07/10
[0009] In one implementation of MMA, connectivity application software of the
MMUE transceiver
module is configured to determine a set of RATs jointly supported by the MMUE
and connected
AP, establish a communication link with the AP utilizing all or a subset of
the jointly supported
RATs, aggregate the traffic streams of simultaneously utilized RATs and
perform traffic split
between simultaneously utilized RATs based on traffic splitting priorities.
[0010] In another implementation of MMA, the connectivity application software
of the MMUE
transceiver module is configured to determine a set of RATs jointly supported
by the MMUE and
connected AP, establish a communication link with the AP utilizing all or a
subset of the jointly
supported RATs, and aggregate the traffic streams of simultaneously utilized
RATs while the
Radio Resource Management (RRM) function at the RAN performs traffic split
between
simultaneously utilized RATs based on traffic splitting priorities.
[0011] In one aspect, a wireless cellular communication system for connecting
user equipment
is provided, the system comprising a radio access network comprising one or
more system radio
access points, the system radio access points utilizing a plurality of radio
access technologies to
connect user equipment, the connected user equipment configured to
simultaneously utilize at
least two radio access technologies jointly supported by the connected user
equipment and the
connecting system radio access points.
[0012] In another aspect, a method is provided for connecting user equipment
to a radio access
network comprising one or more system radio access points, the radio access
points utilizing a
plurality of radio access technologies to connect user equipment is provided,
the method
comprising configuring the connected user equipment to simultaneously utilize
at least two radio
access technologies jointly supported by the connected user equipment and the
connecting
system radio access points.
[0013] In a further aspect, a cellular multimode user equipment (MMUE) is
provided, the MMUE
comprising a processor and a memory, the memory storing instruction which,
when executed by
the processor, cause the processor to provide a connectivity application
software configured to
determine a set of radio access technologies (RAT) jointly supported by the
MMUE and at least
one connected radio access point (AP) and establish a communication link with
the AP utilizing
all or a subset of the jointly supported RATs.
[0014] These and other embodiments are contemplated and described herein. It
will be
appreciated that the foregoing summary sets out representative aspects of
systems and methods
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CA 2931856 2018-07-10
Application no. CA2,931,856
Agent ref: 223-005CAP
Amendment dated 2018/07/10
for cryptographic suite management to assist skilled readers in understanding
the following
detailed description.
DESCRIPTION OF THE DRAWINGS
[0015] A greater understanding of the embodiments will be had with reference
to the Figures, in
which:
[0016] Figure 1 illustrates an exemplary block diagram of a cellular
communication system;
[0017] Figure 2 illustrates a system radio AP layout at a specific geographic
area;
[0018] Figure 3 illustrates an exemplary block diagram of a SMUE;
[0019] Figure 4 illustrates an exemplary block diagram of a MMUE;
[0020] Figure 5 provides a flowchart illustrating the operation of the
connectivity application
software of MMUE;
[0021] Figure 6 illustrates an example of wireless spectrum partitioning
between multiple RATs;
[0022] Figure 7 provides an example of user connectivity under SMA; and
[0023] Figure 8 provides an example of user connectivity under MMA.
DETAILED DESCRIPTION
[0024] For simplicity and clarity of illustration, where considered
appropriate, reference numerals
may be repeated among the Figures to indicate corresponding or analogous
elements. In addition,
numerous specific details are set forth in order to provide a thorough
understanding of the
embodiments described herein. However, it will be understood by those of
ordinary skill in the art
that the embodiments described herein may be practised without these specific
details. In other
instances, well-known methods, procedures and components have not been
described in detail
so as not to obscure the embodiments described herein. Also, the description
is not to be
considered as limiting the scope of the embodiments described herein.
[0025] Various terms used throughout the present description may be read and
understood as
follows, unless the context indicates otherwise: "or" as used throughout is
inclusive, as though
written "and/or'; singular articles and pronouns as used throughout include
their plural forms, and
vice versa; similarly, gendered pronouns include their counterpart pronouns so
that pronouns
should not be understood as limiting anything described herein to use,
implementation,
performance, etc. by a single gender. Further definitions for terms may be set
out herein; these
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Application no. CA2,931,856
Agent ref: 223-005CAP
Amendment dated 2018/07/10
may apply to prior and subsequent instances of those terms, as will be
understood from a reading
of the present description.
[0026] Any module, unit, component, server, computer, terminal or device
exemplified herein that
executes instructions may include or otherwise have access to computer
readable media such as
storage media, computer storage media, or data storage devices (removable
and/or non-
removable) such as, for example, magnetic disks, optical disks, or tape.
Computer storage media
may include volatile and non-volatile, removable and non-removable media
implemented in any
method or technology for storage of information, such as computer readable
instructions, data
structures, program modules, or other data. Examples of computer storage media
include RAM,
ROM, EEPROM, flash memory or other memory technology, CD-ROM, digital
versatile disks
(DVD) or other optical storage, magnetic cassettes, magnetic tape, magnetic
disk storage or other
magnetic storage devices, or any other medium which can be used to store the
desired
information and which can be accessed by an application, module, or both. Any
such computer
storage media may be part of the device or accessible or connectable thereto.
Further, unless the
context clearly indicates otherwise, any processor or controller set out
herein may be
implemented as a singular processor or as a plurality of processors. The
plurality of processors
may be arrayed or distributed, and any processing function referred to herein
may be carried out
by one or by a plurality of processors, even though a single processor may be
exemplified. Any
method, application or module herein described may be implemented using
computer
readable/executable instructions that may be stored or otherwise held by such
computer readable
media and executed by the one or more processors.
[0027] The following obviates or mitigates some or all of the foregoing
issues, including potentially
the underutilization of system radio frequency resources, underutilization of
UE capabilities and
underutilization of the capabilities of system radio APs. In suitable
implementations, the following
may provide optimal UE access to system radio frequency resources, full
utilization of system
radio frequency resources, full utilization of UE capabilities and full
utilization of the capabilities of
system radio APs.
[0028] The following provides a system and method for wireless user equipment
access. The
system comprises radio APs providing connectivity to UE using a plurality of
RATs and MMUE
configured to simultaneously utilize all or a subset of RATs jointly supported
by MMUE and
connecting radio APs. This mode of operation, referred to herein as Multimode
Access (MMA),
may avoid issues caused by limiting MMUE to utilizing a single-RAT when
connecting to system
radio APs deploying multiple RATs, a mode of operation referred to herein as
Single-Mode
CA 2931856 2018-07-10
Application no. CA2,931,856
Agent ref: 223-005CAP
Amendment dated 2018/07/10
Access (SMA). MMUE connecting to system radio APs deploying multiple RATs
under MMA may
utilize (i) all RATs jointly supported by MMUE and connecting system radio
APs; or (ii) a subset
of RATs jointly supported by MMUE and connecting system radio APs. In the
latter case, MMUE
may not utilize all RATs jointly supported by MMUE and connecting system radio
APs for various
reasons that include, but are not limited to, connectivity requirements of
user applications that
may not be fulfilled by certain RATs or are better fulfilled by other RATs,
energy efficiency
considerations and MMUE hardware or processing limitations.
[0029] The MMUE comprises a MMUE transceiver module having a processor and a
memory,
wherein the memory stores instructions which, when executed by the processor,
causes the
processor to provide connectivity application software.
[0030] In one implementation of MMA, the connectivity application software of
the MMUE
transceiver module is configured to determine a set of RATs jointly supported
by the MMUE and
connected AP, establish a communication link with the AP utilizing all or a
subset of the jointly
supported RATs, aggregate the traffic streams of simultaneously utilized RATs
and perform traffic
split between simultaneously utilized RATs based on traffic splitting
priorities.
[0031] In another implementation of MMA, the connectivity application software
of the MMUE
transceiver module is configured to determine a set of RATs jointly supported
by the MMUE and
connected AP, establish a communication link with the AP utilizing all or a
subset of the jointly
supported RATs, and aggregate the traffic streams of simultaneously utilized
RATs while the
Radio Resource Management (RRM) function at the RAN performs traffic split
between
simultaneously utilized RATs based on traffic splitting priorities.
[0032] The connectivity application software aggregates the traffic streams of
simultaneously
utilized bands. On the other hand, traffic split between simultaneously
utilized RATs can be
performed, based on pre-set traffic splitting parameters for different user
applications, by either
the connectivity application software of the UE transceiver module or the RRM
function at the
RAN. Performing traffic split between simultaneously utilized bands by the
connectivity application
software of the UE transceiver module reduces the processing load on the RRM.
On the other
hand, performing the traffic split by the RRM function at the RAN reduces the
processing load on
the connectivity application software of the UE transceiver module and enables
the joint
optimization of the overall allocation of system radio frequency resources by
accounting for UE
capabilities of all system users. =
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CA 2931856 2018-07-10
Application no. CA2,931,856
Agent ref: 223-005CAP
Amendment dated 2018/07/10
[0033] Referring now to Fig. 1, an exemplary network structure for wireless
cellular
communication systems is shown. The network comprises a Radio Access Network
(RAN) (104)
linked to a Core Network (CN) (106). The RAN is deployed to wirelessly connect
User Equipment
(UE) (102) and carry user traffic to the CN (106), where cellular systems are
connected with other
communication systems (108). A RAN typically comprises radio Access Points
(APs) that are
deployed at different locations to facilitate connectivity of UE (102), in
addition to processing units
and equipment (such as antennas, circuits, connecting cables, etc.) that
collectively perform
Radio Transmission Functions (RTFs) (110) and non-Radio Transmission Functions
(non-RTFs)
(112). Connection of UE to system radio APs is facilitated by a wireless radio
air interface, referred
to as the Radio Access Technology (RAT) (100), which utilizes a specific
amount of spectrum.
[0034] RAN RTFs comprise, but are not limited to: wireless signal transmission
and reception,
using antennas housed in system radio APs; modulation and demodulation of
wireless signals
using carrier modem circuits; baseband processing of data using baseband
processors; and
synchronization of system users in frequency and time using synchronization
circuits and signals.
[0035] RAN Non-RTFs comprise, but are not limited to: System Access Control
(SAC) functions,
Radio Resource Management (RRM) functions and User Mobility Management (UMM)
functions.
SAC functions enable admission of authenticated users to access and utilize
system resources
using system user registries. RRM functions include determining which system
users have access
to radio frequency resources at any time using scheduling functions, with
opportunistic scheduling
commonly employed in data cellular systems to exploit wireless channel
variations. UMM
functions include maintaining connectivity of mobile users through user
connection handover;
paging system users to contact the RAN to initiate data transmission sessions;
and user location
positioning to enable location-based services.
[0036] RAN functions (both RTFs and non-RTFs) can be implemented in a single
entity or in
multiple entities. The Long-Term Evolution (LTE) standard is an example of
single entity RAN
implementations; as all RAN functions are implemented in a single RAN entity
referred to as the
enhanced Node B (eNB). On the other hand, The Universal Mobile
Telecommunication System
(UMTS) system implements RTFs in a RAN element referred to as the Node B (NB)
while non-
RTFs are implemented in a RAN element referred to as the Radio Network
Controller (RNC).
Note that RAN functions can be implemented over more than two elements and
that both RTFs
and non-RTFs can be implemented in any RAN element.
[0037] The choice of RAT transmission bandwidths and deployment configuration
at any system
radio AP is dependent on the amount of spectrum available for the mobile
network operator
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CA 2931856 2018-07-10
Application no. CA2,931,856
Agent ref: 223-005CAP
Amendment dated 2018/07/10
deploying the cellular communication system and the interference levels at
system radio APs.
Fig. 2 illustrates a top view layout of system radio AP deployment comprising
ten radio APs
deployed at different locations to provide required coverage and capacity at a
specific
geographical area. The coverage area of radio APs is referred to as cells
(120) and is determined
by the radio AP transmission power and radio propagation conditions. The
coverage area of a
radio AP utilizing a particular set of radio frequency resources, i.e. a
particular set of carriers,
specifies the area in which a radio AP causes significant levels of
interference that constrains the
reuse of the same set of radio frequency resources by any other radio AP in
that area. In the
example of Fig. 2, radio APs AP3 (126) and AP10 (140) have overlapping
coverage. Similarly,
radio APs AP2 (124), AP5 (130) and AP6 (132) also have overlapping coverage.
On the other
hand, radio APs AP7 (134) and AP9 (138) do not have overlapping coverage and
can thus utilize
the same set of radio frequency resources at any time. However, the coverage
of both radio APs
AP7 (134) and AP9 (138) overlaps with the coverage of AP4 (128) and AP8 (136).
Therefore,
radio APs AP7 (134) and AP9 (138) must both avoid interfering with radio APs
AP4 (128) and
AP8 (136) at anytime. Conversely, the coverage of radio AP AP1 (122) does not
overlap with the
coverage of any other system radio AP in the example of Fig. 2. All available
system radio
frequency resources can thus be utilized at AP1 (122) at any time. It should
be understood that
the provided radio AP deployment layout in Fig. 2 is for illustrative purposes
only and that other
deployment layouts are contemplated.
[0038] In terms of RAT support, UE can be broadly categorized into Single Mode
User Equipment
(SMUE), capable of utilizing a single RAT only, and Multimode User Equipment
(MMUE), capable
of utilizing multiple RATs. Variations in the capabilities of UE require the
deployment of multiple
RATs in cellular communication systems to maintain connectivity of both SMUE
and MMUE. This
consequently requires the partitioning of spectrum between RATs co-deployed at
any system AP
and in addition to RATs deployed at system radio AF's having overlapping
coverage, with each
RAT typically assigned one or more blocks of spectrum in most implementations.
The
transmission bandwidth for each RAT is typically determined at the time of
deployment, and
perhaps reconfigured from time to time, to reflect typical RAT utilization and
traffic demand. A
cellular communication system could support one or more RATs and generally
assigns bands or
sub-bands to each of the employed RATs at system radio APs using a
configuration that is
typically based on a historical, current and/or projected usage for each RAT
such that RATs with
higher utilization and traffic demand are assigned more spectrum, and vice
versa.
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CA 2931856 2018-07-10
Application no. CA2,931,856
Agent ref. 223-005CAP
Amendment dated 2018/07/10
[0039] An exemplary structure of a SMUE transceiver module is shown in Fig. 3.
The SMUE
transceiver module (142) comprises both dedicated communication hardware (144)
and a
software component divided into connectivity application software (148) and
dedicated
communication software (146) specific to the utilized RAT. Subsequently, as
Fig. 4 shows, MMUE
transceiver modules support multiple RATs by integrating communication
processors and
software of the supported RATs with the connectivity application software. In
the example of Fig.
4, an exemplary structure of a MMUE transceiver module supporting three RATs
is shown. The
MMUE transceiver module (142') comprises dedicated communication processors
for RAT 1
(144'), RAT 2 (144") and RAT 4 (144¨) supplemented by dedicated communication
software for
RAT 1 (146'), RAT 2 (146") and RAT 4 (146-) (i.e., RAT 3 is not supported by
this MMUE). The
connectivity application software (148') is configured to determine RATs
supported by the
connecting system radio AP(s). It is further configured to establish a
communication link with a
single or set of system radio APs utilizing a single RAT under SMA and all or
a subset of the jointly
supported RATs under MMA, and orchestrate the module operation for all
supported RATs.
Furthermore, the connectivity application software (148') continuously adapts
the RAT(s) MMUE
utilize to communicate with different system radio APs as well as when the
connectivity
requirements of user applications change. For example, the connectivity
application software
(148') may switch the utilized RAT to preserve energy at the UE.
[0040] Fig. 6 shows an example of spectrum partitioning between four RATs
deployed in the
same geographical area, with RAT performance monotonically increasing (i.e.
RAT 4 outperforms
RAT 3 and RAT 3 outperforms RAT 2 and RAT 2 outperforms RAT 1). In this
example, spectrum
at two non-contiguous radio frequency bands, the first comprising two spectrum
blocks (150, 152)
and the second comprising three spectrum blocks (154, 156, 158), is
apportioned between
deployed RATs, RAT 1 utilized over two blocks: Block 1 of Band 1 ((Carrier 1
or Cl (150)) and
Block 1 of Band 2 (Carrier 2 or C2 (154)), RAT 2 utilized over Block 2 of Band
1 (152), RAT 3
utilized over Block 2 of Band 2 (156) and RAT 4 utilized over Block 3 of Band
2 (158). A possible
mapping of the spectrum partitioning of Fig. 6 to the system radio AP layout
of Fig. 2 would have
all RATs co-deployed over all spectrum blocks (150¨ 158) at AP1 (122), RAT 1
Cl (150) deployed
at AP2 (124), AP3 (126), and AP4 (128), RAT 1 C2 (154) and RAT 2 (152) co-
deployed at AP5
(130), AP7 (134) and AP9 (138), RAT 3 (156) and RAT 4 (158) co-deployed at AP6
(132) and
AP8 (136) and RAT 1 C2 (154), RAT 2 (152), RAT 3 (156) and RAT 4 (158) co-
deployed at AP10
(140). It should be understood that the provided spectrum partitioning example
in Fig. 6 in addition
to the mapping example for the layout of Fig. 2 are for illustrative purposes
only and that other
contiguous and non-contiguous frequency band plans are contemplated.
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Application no. 0A2,931 856
Agent ref: 223-005CAP
Amendment dated 2018/07/10
[0041] UE in cellular communication systems are typically configured to
utilize only a single RAT
when connecting to system APs. Subsequently, MMUE operating in SMA connecting
to system
radio APs deploying multiple RATs typically utilize the highest performing RAT
jointly supported
by MMUE and connecting system radio APs, referred to as the primary mode of
operation and
typically identified by the connectivity application software of the MMUE
transceiver module, with
the connectivity application software of the MMUE transceiver module
continuously adjusting the
utilized RAT as MMUE connect to different system radio APs as well as when the
connectivity
requirements of user applications change. SMA can result in the suboptimal
utilization of system
radio frequency resources, MMUE capabilities and capabilities of system radio
APs.
[0042] Referring now to Fig. 7, an example of five UE, UE1 (160), UE2 (162),
UE3 (164), UE4
(166) and UE5 (168), connecting under SMA to three system radio APs adopting
the frequency
plan based on the system radio AP layout of Fig. 2 and the frequency band plan
example of Fig.
6, AP1 (122'), AP3 (126') and AP10 (140'), is provided. All RATs co-deployed
over all spectrum
blocks (150¨ 158) at AP1 (122'), RAT 1 Cl (150) is deployed at AP3 (126') and
RAT 1 C2 (154),
RAT 2 (152), RAT 3 (156) and RAT 4 (158) co-deployed at AP10 (140'). In this
example, UE1
(160), UE2 (162) and UE3 (164) connect to AP1 (122') while UE4 connects to
AP10 (140') and
UE5 (168) simultaneously connects to AP3 (126') and AP10 (140'). While SMUE
are capable of
utilizing a single RAT only when connecting to system radio APs, the
constraint of SMA limits
MMUE connectivity to system APs to the primary mode of operation, i.e. a
single RAT only.
Specifically, UE1 (160) connects to AP1 (122') using RAT 3 (156'), UE2 (162)
connects to AP1
(122') using RAT 4 (158'), UE3 (164) connects to AP1 (122') using RAT 4
(158'), UE4
simultaneously connects to AP3 (126') using RAT 1 Cl (150') and AP10 (140')
using RAT 1 C2
(154') while UE5 (168) connects to AP10 (140') using RAT 4 (158'). Therefore,
in the example of
Fig. 7, system radio frequency resources assigned to RAT 1 (150, 154) and RAT
2 (152) at AP1
(122') are completely unutilized in spite of connecting a UE, UE2 (162),
capable of utilizing RAT
1 (150, 154) and RAT 2 (152). Similarly, system radio frequency resources
assigned to RAT 2
(152) and RAT 3(156) are completely unutilized at AP10 (140') in spite of
connecting UE5 (168)
capable of utilizing RAT 2 (152) and RAT 3 (156). While the example of Fig. 7
clearly illustrates
the aforementioned limitations imposed by SMA, it should be understood that
the configuration
provided in Fig. 6 is for illustrative purposes only and that other
configurations are contemplated.
[0043] To circumvent the limitations of SMA, MMUE are allowed to
simultaneously utilize all RATs
jointly supported by MMUE and connecting radio APs under Multimode Access
(MMA). To
illustrate UE connectivity under MMA and contrast MMA to SMA, Fig. 8
illustrates UE connectivity
CA 2931856 2018-07-10
Application no. CA2,931,856
Agent ref: 223-005CAP
Amendment dated 2018/07/10
under MMA for the same UE and system radio AP configuration provided in Fig.
7. Connectivity
of UE1 (160') to API (122") is unaffected by the enablement of MMA as UE1
(160') is capable of
utilizing a single RAT only (RAT 3 (156")). On the other hand, UE2 (162')
simultaneously utilizes
all RATs jointly supported by UE2 (162') and AP1 (122") (RAT 1(150", 154"),
RAT 2(152") and
RAT 4 (158")) when connecting to AP1 (122"). Similarly, UE3 simultaneously
utilizes RAT 3
(156") and RAT 4 (158") when connecting to AP1 (122"). Similar to UE1 (160'),
UE4 (166') is
unaffected by the enablement of MMA and utilizes RAT 1 Cl (150") to connect to
AP3 (126")
while simultaneously connecting to AP10 (140") using RAT1 C2 (154").
Conversely, UE5 (168')
connects to AP3 (126") using RAT1 01(150") while simultaneously connecting to
AP10 (140")
using RAT 1 C2 (152"), RAT 2 (152"), RAT 3 (156"), and RAT 4 (158"). When
compared to the
example of Fig. 7, system radio frequency resources are fully utilized at all
system radio APs
under MMA as opposed to being partially utilized under SMA. Once again, it
should be understood
that the example provided in Fig. 8 is for illustrative purposes only and that
other configurations
are contemplated.
[0044] Fig. 5 illustrates exemplary operation of the connectivity application
software of MMUE in
MMA. At block 500, the connectivity application software is initialized in
response to a user
application requiring a data connection. At block 502, the connectivity
application software
performs measurements for all supported RAT(s) over all supported bands to
determine the
performance capabilities of the RAT(s). At block 504, the connectivity
application software
determines the optimal radio AP(s), RAT(s) and band(s) to utilize based on the
needs of the
particular user application and the performance capabilities previously
determined. At block 506,
the connectivity application software causes the MMUE to establish a
connection to each APs
using the selected RAT(s) and band(s). At block 508, the connectivity
application software
performs the measurements of block 502, and blocks 504, 506 and 508 repeat
during the course
of connectivity.
[0045] Therefore, the utilization of system radio frequency resources, in
addition to the utilization
of UE capabilities and system radio AP capabilities, is substantially improved
with the enablement
MMA.
[0046] While MMA enables MMUE to simultaneously utilize all RATs jointly
supported by MMUE
and connecting system radio APs, MMUE may utilize a subset of RATs jointly
supported by
MMUE and connecting system radio APs for various reasons that include, but are
not limited to,
cost considerations, connectivity requirements of user applications that may
not be fulfilled by
certain RATs or are better fulfilled by other RATs, energy efficiency
considerations and MMUE
11
CA 2931856 2018-07-10
Application no. CA2,931,856
Agent ref: 223-005CAP
Amendment dated 2018/07/10
hardware or processing limitations. Traffic split between simultaneously
utilized RATs is thus
based on the traffic demand of user applications, the connectivity
requirements of user
applications, the traffic capacity of utilized RATs in addition to traffic
splitting priorities. For
example, if the user application traffic demand can be met by utilizing one of
two RATs only and
energy efficiency is prioritized then user traffic may be carried using the
most energy efficient RAT
of the two RATs capable of meeting user application traffic demand. In another
example, traffic
may be split between three RATs to achieve better energy efficiency when
compared to utilizing
a single RAT. It must be appreciated that such examples are for clarification
purposes only and
that other traffic split considerations and implementations are contemplated.
[0047] Similar to multi-band connectivity, the connectivity application
software of the MMUE
transceiver module aggregates traffic streams of simultaneously utilized RATs
while traffic split
between simultaneously utilized RATs can be performed, based on pre-set
traffic splitting
parameters for different user applications, by either the connectivity
application software of the
MMUE transceiver module or the RRM function at the RAN. Performing traffic
split between
simultaneously utilized RATs by the connectivity application software of the
MMUE transceiver
module reduces the processing load on the RRM function at the RAN, and thus
avoids imposing
any implementation requirements on the RAN when transitioning from SMA to MMA.
In contrast,
performing the traffic split by the RRM function at the RAN reduces the
processing load on the
connectivity application software of the MMUE transceiver module and enables
the joint
optimization of the overall allocation of system radio frequency resources by
accounting for UE
capabilities of all system users. Similar to multi-band connectivity, traffic
split mechanisms include,
but are not limited to, sequential and weighted traffic split. Under
sequential traffic split, traffic
demand is steered at a designated RAT and traffic demand exceeding the
capacity provided by
the designated RAT is steered at another designated RAT and so on. On the
other hand, weighted
traffic split divides traffic between RATs based on RAT capacity and packet
latency, such that
RATs providing equal capacity and packet latency would carry equal amounts of
traffic.
[0048] Although the foregoing has been described with reference to certain
specific
embodiments, various modifications thereto will be apparent to those skilled
in the art without
departing from the scope of the invention as outlined in the appended claims.
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CA 2931856 2018-07-10
