Note: Descriptions are shown in the official language in which they were submitted.
CA 02635874 2008-06-30
WO 2007/079058 PCT/US2006/049214
[0001] METHOD AND APPARATUS FOR SELECTING MULTIPLE
TRANSPORT FORMATS AND TRANSMITTING MULTIPLE
TRANSPORT BLOCKS SIMULTANEOUSLY WITH
MULTIPLE H-ARQ PROCESSES
[0002] FIELD OF INVENTION
[0003] The present invention is related to wireless communication systems.
More particularly, the present invention is related to a method and apparatus
for selecting multiple transport formats and transmitting multiple transport
blocks (TBs) in a transmission time interval (TTI) simultaneously with
multiple
hybrid automatic repeat request (H-ARQ) processes in a wireless communication
system.
[0004] BACKGROUND
[0005] The objective of evolved high speed packet access (HSPA+) and long
term evolution (LTE) of universal terrestrial radio access (UTRA) and
universal
terrestrial radio access network (UTRAN) is to develop a radio access network
for
high data rate, low latency, packet optimization, and improved system capacity
and coverage. In order to achieve these goals, an evolution of a radio
interface
and radio network architecture are,being considered. In HSPA+, the air
interface
technology will still be based on code division multiple access (CDMA) but
with
more efficient physical layer architecture which may include independent
channelization codes, (distinguished with regard to channel quality), and
multiple-input multiple-output (MIMO). In LTE, orthogonal frequency division
multiple access (OFDMA) and frequency division multiple access (FDMA) are
proposed as the air interface technologies to be used in the downlink and the
uplink, respectively.
[0006] H-ARQ has been adopted by several wireless communication
standards, including third generation partnership project (3GPP) and 3GPP2.
Besides radio link control (RLC) layer automatic repeat request (ARQ)
function,
-1-
CA 02635874 2008-06-30
WO 2007/079058 PCT/US2006/049214
,
H-ARQ improves throughput, compensates for link adaptation errors and
provides efficient transmission rates through the channel. The delay caused by
H-ARQ feedback, (i.e., a positive acknowledgement (ACK) or a negative
acknowledgement (NACK)), is significantly reduced by placing the H-ARQ
functionality in a Node-B rather than in a radio network controller (RNC). A
user equipment (UE) receiver may combine soft bits of the original
transmission
with soft bits of subsequent retransmissions to achieve higher block error
rate
(BLER) performance. Chase combining or incremental redundancy may be
implemented.
[0007] ' Asynchronous H-ARQ is used in high speed downlink packet access
(HSDPA) and synchronous H-ARQ is used in high speed uplink packet access
(HSUPA). In both HSDPA and HSUPA, radio resources allocated for the
transmission are the number of codes at a certain frequency band based on one
channel quality indication (CQI) feedback. There is no differentiation among
channelization codes. Therefore, one HSDPA medium access control (MAC-hs)
flow or one HSUPA medium access control (MAC-e/es) flow multiplexed from
multiple dedicated channel MAC (MAC-d) flows is assigned to one H-ARQ process
and one cyclic redundancy check (CRC) is attached to one transport block.
[0008] A new physical layer attribute introduced in HSPA+ includes MIMO
and different channelization codes. New physical layer attributes introduced
in
LTE include MIMO and different subcarriers, (localized or distributed). With
introduction of these new physical layer attributes, the performance of
conventional single H-ARQ scheme and transport format combination (TFC)
selection procedure should be changed. In a conventional single H-ARQ scheme,
only one H-ARQ process is active at a time and a TFC of only one transport
data
block needs to be determined in each TTI. The conventional TFC selection
procedure does not have the ability to make TFC selection for more than one
data
block for multiple H-ARQ processes.
-2-
CA 02635874 2008-06-30
WO 2007/079058 PCT/US2006/049214
[0009] SUMMARY
[0010] The present invention is related to a method and apparatus for
selecting multiple transport formats and transmitting multiple TBs in a TTI
simultaneously with multiple H-ARQ processes in a wireless communication
system. Available physical resources and the channel quality of each of the
available physical resources are determined, and the H-ARQ processes
associated
with the available physical resources are identified. Quality of service (QoS)
requirements of higher layer data flow(s) to be transmitted are determined.
The
higher layer data flow(s) is mapped to at least two H-ARQ processes. Physical
transmission parameters and H-ARQ configurations to support QoS
requirements of the higher layer data flow(s) mapped to each H-ARQ process are
determined. TBs are generated from the mapped higher layer data flow(s) in
accordance with the physical transmission parameters and H-ARQ configurations
of each H-ARQ process, respectively. The TBs are transmitted via the H-ARQ
processes simultaneously.
[0011] BRIEF DESCRIPTION OF THE DRAWINGS
[0012] A more detailed understanding of the invention may be had from the
following description of a preferred embodiment, given by way of example and
to
be understood in conjunction with the accompanying drawings wherein:
[0013] Figure 1 is a block diagram of an apparatus configured in
accordance with the present invention; and
[0014] Figure 2 is a flow diagram of a process for transmitting multiple
TBs in a TTI simultaneously with multiple H-ARQ processes in accordance with
the present invention.
[0015) DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0016] When referred to hereafter, the terminology "wireless
transmit/receive unit" (WTRU) includes but is not limited to a user equipment
(UE), a mobile station, a fixed or mobile subscriber unit, a pager, a cellular
telephone, a personal digital assistant (PDA), a computer, or any other type
-3-
CA 02635874 2008-06-30
WO 2007/079058 PCT/US2006/049214
of user device capable of operating in a wireless environment. When referred
to
hereafter, the terminology "base station" includes but is not limited to a
Node-B,
an evolved Node-B (eNB), a site controller, an access point (AP), or any other
type
of interfacing device capable of operating in a wireless environment.
[0017] The present invention is applicable to any wireless communication
system including, but not limited to, wideband code division multiple access
(WCDMA), CDMA2000, HSPA+, LTE of 3GPP systems, OFDM, MIMO or
OFDM/MIMO.
[00181 The features of the present invention may be incorporated into an
integrated circuit (IC) or be configured in a circuit comprising a multitude
of
interconnecting components.
[0019] Different antenna spatial beams or channelization codes may
experience a different channel quality, which may be indicated by CQI
feedback.
The same adaptive modulation and coding (AMC) may be applied to all the
subcarriers, spatial beams or channelization codes which are independent of
the
quality of the subcarriers, spatial beams and channelization codes.
Alternatively,
the channel condition may be used to apply different AMC to different
subcarriers, spatial beams or channelization codes in order to maximize the
performance.
[0020] When subcarrier, spatial beam or channelization code-dependent
AMC is used, each data block that 'is assigned to each subcarrier, spatial
beam or
channelization code is associated with one CRC in accordance with the present
invention. Otherwise, upon transmission error, the entire packet distributed
to
different subcarriers, spatial beams or channelization codes need to be
retransmitted because the whole packet is associated with a single CRC.
Retransmitting every data block that has already been correctly received will
waste the valuable radio resources. The same situation applies when MIMO is
used because each antenna may be subject to different channel conditions.
Thus,
when multi-dimensional H-ARQ processes are used with each H-ARQ process
corresponding to one or more subcarriers, channelization codes, transmit
antennas (or spatial beams), a separate CRC is attached to each transport data
-4-
CA 02635874 2008-06-30
WO 2007/079058 PCT/US2006/049214
block in accordance with the present invention. In a conventional single H-ARQ
scheme, only one H-ARQ process is active at a time and a TFC of only one
transport data block needs to be determined in each TTI. The conventional TFC
selection procedure does not have the ability to make TFC selection for more
than
one data block for multiple H-ARQ processes to properly support QoS
requirements of higher layer data flows.
[0021] Figure 1 is a block diagram of an apparatus 100 for transmitting
multiple transport blocks (TBs) simultaneously in a transmission time interval
(TTI) with multiple H-ARQ processes in accordance with the present invention.
The apparatus 100 may be a WTRU, a Node-B, or any other communication
device. The apparatus 100 includes a plurality of H-ARQ processes 102a-102n, a
plurality of multiplexing and link adaptation processors 104a-104n and a
controller 106. Each multiplexing and link adaptation processor 104a-104n is
associated with one H-ARQ process 102a-102n. Each multiplexing and link
adaptation processor 104a-104n receives physical resource configuration,
(i.e.,
sub-carriers distributed or localized, MIMO antenna configurations, or the
like),
and CQIs associated with these physical resources.
[0022] Each available H-ARQ process 102a-102n is associated with a
specific set of physical resources. The association of physical resources to
the H-
ARQ processes 102a-102n may be determined dynamically, or the association
may be semi-statically configured. A network entity, (e.g., an eNB scheduler),
determines how many physical resources should be assigned. Physical resources
associated with a particular H-ARQ process may be dynamically reassigned each
time a TFC is selected by the multiplexing and link adaptation processor 104a-
104n or each time the H-ARQ processor 102a-102n generates an H-ARQ
retransmission for a particular TB. The reassignment of physical resources may
be performed based on the CQI of particular physical resources or determined
based on a predefined hopping pattern.
[0023) The multiplexing and link adaptation processors 104a-104n perform
link adaptation independently for each set of physical resources and
associated
H-ARQ processes 102a-102n. Each multiplexing and link adaptation processor
-5-
CA 02635874 2008-06-30
WO 2007/079058 PCT/US2006/049214
104a-104n determines a modulation and coding scheme (MCS), a multiplexed TB,
transmit power requirement, an H-ARQ redundancy version and maximum
number of retransmissions each TTI. This set of transmission information is
provided to each H-ARQ process 102a-102n.
[0024] The physical resources may be defined by independent spatial
streams (if MIMO is implemein.ted) in the space domain, independent
subcarriers
(if OFDMA or FDMA is implemented) in the frequency domain, independent
channelization codes (if CDMA is implemented) in the code domain, independent
timeslots in the time domain, or any combination thereof. The independent
subcarriers may be distributed or localized. The channelization codes are
physical resources that can be assigned to different TBs independently. In
CDMA systems, different channelization codes may be assigned to transmit one
TB, or several TBs based on the channel condition and data rate requirement
for
each TB. The maximum number of TBs that can be transmitted is less or equal
to the maximum number of channelization codes available. When several
independent spatial streams, subcarriers or channelization codes are
available,
several TBs may be transmitted simultaneously via different physical resources
with several H-ARQ processes. For example, if two spatial streams are
available
in a 2x2 MIMO system, two TBs may be transmitted simultaneously via two
spatial streams with two independent H-ARQ processes.
[0025] Different physical resources, (i.e., different subcarriers, antenna
spatial beams, channelization codes or timeslots), may experience different
channel quality. The quality of each physical resource is determined by one or
more CQI measurements. The CQI may be fed back from a communication peer
or may be obtained based on channel reciprocity. The CQI may also be
represented by an allowed MCS and/or maximum transport block size. .
[0026] The controller 106 identifies available physical resources and H-
ARQ processes associated with the. available physical resources. Since each H-
ARQ process 102a-102n is associated with a particular physical resource, when
available physical resources are identified, available H-ARQ processes are
also
identified. The available physical resources and associated H-ARQ processes
-6-
CA 02635874 2008-06-30
WO 2007/079058 PCT/US2006/049214
may be determined at the start of a common TTI boundary. The association may
also be semi-statically configured over a period of multiple TTIs.
[0027] The available physical resources are the number of independent
spatial streams, subcarriers, channelization codes and timeslots that can be
used
for data transmission within a certain period. The available physical
resources
for one WTRU are dependent on many factors such as number of WTRUs that a
Node-B needs to support in one cell, the interference level from other cells,
the
channel condition of the WTRU, the QoS levels (such as priorities, latency,
fairness and buffer status) of the services the WTRU needs to support, the
data
rates one WTRU needs to support, or the like.
[00281 In accordance with the present invention, multiple H-ARQ processes
102a-102n operate simultaneously and in parallel. Since H-ARQ processes 102a-
102n may take a different number of retransmissions for successful
transmission
and since the data flows mapped to the H-ARQ processes 102a-102n may have
QoS requirements that determine a different maximum number of
retransmissions or different TTI sizes, a certain H-ARQ may not be available
if
H-ARQ processes are not synchronized with each other. Any number of H-ARQ
processes may become available in any TTI. In accordance with the present
invention, more than one H-A.RQ process and associated set of physical
resources
become available in a common TTI. The association between H-ARQ processes
and physical resources is coordinated by the controller 106.
[0029] The controller 106 maps higher layer data flows 108a-108m, (i.e.,
multiple flows of MAC or RLC protocol data units (PDUs)), to at least two
multiplexing and link adaptation processors 104a-104n and their associated H-
ARQ processes 102a-102n. The same higher layer data flow 108a-108m may be
mapped to more than one multiplexing and link adaptation processor 104a-104n
and H-ARQ process 102a-102n in='a common TTI for QoS normalization. By
mapping the same higher layer data flow or set of higher layer data flows to
multiple H-ARQ processes, QoS requirement across the H-ARQ process 102a-
102n is common. In this case, each multiplexing and link adaptation processor
104a-104n determines an MCS, a transport block size, a transmit power,
-7-
CA 02635874 2008-06-30
WO 2007/079058 PCT/US2006/049214
maximum H-ARQ transmissions and transmission parameters in accordance
with the CQIs of the set of associated physical resources so that the QoS
achieved
for each transmission of the higher layer data flow or set of data flows is as
similar as possible.
[0030] Alternatively, unequal error protection may also be achieved by
mapping the higher layer data flows 108a-108m, that may be grouped in
accordance with QoS requirements to different H-ARQ processes 102a-102n
based on the data flow QoS requirements and CQIs associated with the set of
physical resources assigned to each H-ARQ process. For example, CQIs may
show that one set of physical resources is better than other sets of physical
resources. A higher layer data flow with higher QoS requirements may be
mapped to an H-ARQ process associated with better physical resources. The
number of higher layer data flows that will be mapped to a specific H-ARQ
process is determined based on the QoS requirements of the higher layer data
flows, packet size, H-ARQ capacity; or the like. Once the respective higher
layer
data flows to be transmitted using specific H-ARQ processes are decided, those
data flows are multiplexed through the multiplexing and link adaptation
processors 104a - 104n for different H-ARQ processes.
[0031] Each multiplexing and link adaptation processor 104a- 104n receives
an input, (such as, CQIs of the assigned physical resources, buffer occupancy
of
the mapped data flows, or the like), and determines physical transmission
parameters and H-ARQ configurations to support QoS requirements of the higher
layer data flows 108a-108m mapped to each H-ARQ process. The physical
transmission parameters include a transmission power, a modulation and coding
scheme, a TTI size, a transport block size and a beamforming pattern, the
subcarrier allocation, MIMO antenna configuration or the like. The H-ARQ
configuration parameters include an H-ARQ identity, a maximum number of
retransmissions, a redundancy version (RV), a CRC size, or the like. The
multiplexing and link adaptation processor 104a-104n provides the H-ARQ
parameters to the associated H-ARQ process 102a-102n.
[0032] The multiplexing and link adaptation processor 104a-104n may
-8-
CA 02635874 2008-06-30
WO 2007/079058 PCT/US2006/049214
=.,:
apply the same MCS, transport block size, TTI size and/or transmit power to
all
physical resources which are independent of the quality of the physical
resources.
Alternatively, the multiplexing' arid link adaptation processor 104a-104n may
apply different MCS, transport block size, TTI size and/or transmit power to
different physical resources based on channel condition in order to maximize
tlie=
performance.
[0033] When physical resource-dependent AMC and H-ARQ operation is
used, each data block that is assigned to each physical resource is preferably
associated with a separate CRC. With this scheme, the entire packet
distributed
to different physical resources does not need to be retransmitted upon a
transmission error because each transport block is associated with a separate
CRC and is processed by a separate H-ARQ process 102a-102n.
[0034] The multiplexing and link adaptation processors 104a-104n then
generate TBs from the assigned higher layer data flows 112a-112m after
selecting a proper TFC, (i.e., TB size, TB set size, TTI size, modulation and
coding scheme (MCS), transmission power, antenna beams, the subcarrier
allocation, CRC size, redundancy version (RV) and data block to radio resource
mapping, or the like), for the TB based on channel quality indicators and the
physical transmission parameters: One or more higher layer data flows may be
multiplexed into one TB. A separate CRC is attached to each of the TBs for
separate error detection and H-ARQ processing. Each TB and associated
transmission parameters are provided to the assigned H-ARQ process 102a-102n.
The TBs are then transmitted via the assigned H-ARQ processes 102a-102n,
respectively.
[0035] The parameters supporting multiple H-ARQ processes may be
signaled to a receiving peer before transmission or a blind detection
technique
may be used at the receiving peer to decode the transmission parameters. The
generated TBs along with the associated transmission parameters are sent to
the
H-ARQ processes 102a-102n for transmission.
[0036] Figure 2 is a flow diagram of a process 200 for transmitting multiple
TBs in a TTI simultaneously with multiple H-ARQ processes in accordance with
-9-
CA 02635874 2008-06-30
WO 2007/079058 PCT/US2006/049214
the present invention. Available physical resources and their channel quality
associated with each H-ARQ process 102a-102n are identified (step 202). QoS
requirements and buffer occupancy of higher layer data flow 112a-112m to be
transmitted are determined (step 204). It should be noted that the steps in
the
process 200 may be performed in different order and some steps may be
performed in parallel. For example, the step 204 may be applied before the
step
202, or simultaneously.
[0037] The controller 106 may determine the type of higher layer data
flows 112a-112m for TFC selection processing based on QoS parameters
associated with those higher layer data flows. The controller 106 may also
determine the order in which the higher layer data flows are serviced. The
order
of processing may be determined.-by QoS requirements or absolute priority.
Alternatively, a life span time parameter may be used in determining the
duration that the higher layer data packets may stay in an H-ARQ queue so that
the controller 106 may prioritize or discard higher layer data packets based
on
the life span time parameter.
[0038] The higher layer data,flows 112a-112 are mapped to the respective
H-ARQ processes 102a-102n by the controller 106. Physical transmission
parameters and H-ARQ configurations are determined for each of the available
H-ARQ processes 102a-102n to support the required QoS of the higher layer data
flows 112a-112m mapped to each of the H-ARQ processes 102a-102n (step 206).
When more than one H-ARQ process is available for transmission in a TTI, it is
necessary to determine which higher layer data flows 112a-112m should be
mapped to different H-ARQ processes. The higher layer data flows 112a-112m
may or may not have similar QoS requirements.
[0039] When all or a subset of higher layer data flows 112a-112m to be
mapped to different HARQ processes require similar QoS, then the QoS provided
by the H-ARQ processes 102a-102ri is normalized, (i.e., transmission
parameters,
(such as, MCS, TB size and transmission power), and H-ARQ configurations are
adjusted each TTI a TFC is selected such that the QoS provided across the H-
ARQ processes 102a-102n is similar). The QoS normalization across multiple H-
-10-
CA 02635874 2008-06-30
WO 2007/079058 PCT/US2006/049214
ARQ processes 102a-102n may be realized by adjusting the link adaptation
parameters (e.g., MCS, TB size, transmission power, or the like) across the H-
ARQ processes 102a-102n. For example, a higher MCS may be assigned to the
physical resources that have better channel quality and a lower MCS may be
assigned to the physical resources that have worse channel quality. This may
result in different sizes of the multiplexed data block for different H-ARQ
processes.
[0040] Alternatively, when the higher layer data flows 112a-112m require
different QoSs, the higher layer data flows 112a-112m maybe mapped to H-ARQ
processes 102a-102n associated with physical resources with quality that
closely
matches the QoS requirements of the higher layer data flows 112a-112m. An
advantage of using multiple H-ARQ processes is its flexibility to multiplex
logical
channels or MAC flows with different QoS requirements to different H-ARQ
processes 102a-102n and associated=physical resources. When a certain physical
resource indicates a better channel quality than others, data with a higher
QoS is
mapped to the H-ARQ process associated with that physical resource. This
enhances physical resource utilization and maximizes system throughput.
Alternatively, or additionally, an MCS and/or the maximum number of
retransmissions may be configured to differentiate the QoS to more closely
match
the logical channel or MAC flow's QoS requirements.
[0041] After the higher layer= data flows 112a-112m are mapped to the H-
ARQ processes 102a-102n, a TB for each H-ARQ process 102a-102n is generated
in accordance with the physical transmission parameters and H-ARQ
configurations for each H-ARQ process 102a-102n, respectively, by multiplexing
the higher layer data flows 112a-112m associated with each H-ARQ process
102a-102n (step 208). Data multiplexing for each H-ARQ process 102a-102n may
be processed sequentially or in parallel. The TBs are then transmitted
simultaneously via the associated H-ARQ processes 102a-102n (step 210).
[0042] The transmitted TBs may or may not be successfully received at the
communication peer. A failed TB is retransmitted in a subsequent TTI.
Preferably, the size of the retransmitted TB remains the same for soft combing
at
-11-
CA 02635874 2008-06-30
WO 2007/079058 PCT/US2006/049214
the communication peer. Several options are possible for retransmission of the
failed TB.
[0043] In accordance with the first option, the physical resources allocated
for H-ARQ retransmission of the TB remain unchanged, (i.e., the failed TB is
retransmitted via the same physical resources and H-ARQ process. The
transmission parameters and H-ARQ configurations, (i.e., a TFC), may be
changed.. Specifically, the link adaptation parameters, (such as antenna
selection, AMC or transmit power), may be changed to maximize the chance of
successful delivery of the retransmitted TB. When the link adaptation
parameters are changed for retransmission of the failed TB, the changed
parameters may be signaled to the receiving peer. Alternatively, a blind
detection technique may be applied at the receiving peer to eliminate the
signaling overhead for changed parameters.
[0044] In accordance with the second option, physical resources allocated
for H-ARQ retransmission of the transport block may be dynamically reassigned,
(i.e., the failed TB is retransmitted on different physical resources and the
same
H-ARQ process). The reassignment of physical resources may be based on CQI or
based on a known hopping pattern.
[0045] In another option, a failed H-ARQ transmission may be fragmented
across multiple H-ARQ processes and each fragment transmitted independently
to increase the probability of successful H-ARQ transmission. In accordance
with
this option, the physical resources for the retransmitted TB are newly
allocated,
(i.e., the failed TB is transmitted via a different H-ARQ process). The H-ARQ
process used to transmit the failed TB in the previous TTI becomes available
for
transmission of any other TB in the subsequent TTI. The maximum transmit
power, the number of subcarriers or channelization codes, the number or
allocation of antennas and recommended MCS may be re-allocated for
retransmission of the failed TB. Preferably, a new allowed TFCS subset may be
generated to reflect the physical resource change for the failed TB. The new
parameters may be signaled to the receiving peer to guarantee successful
reception. Alternatively, a blind detection technique may be applied at the
-12-
CA 02635874 2008-06-30
WO 2007/079058 PCT/US2006/049214
receiving peer to eliminate the signaling overhead for changed parameters.
[0046] Embodiments.
[0047] 1. A method for transmitting multiple TBs in a TTI with
multiple H-ARQ processes in a wireless communication system.
[0048] 2. The method of embodiment 1 comprising the step of
identifying available physical resources and associated H-ARQ processes.
[0049] 3. The method as in any of the embodiments 1-2, comprising the
step of obtaining channel quality nieasurement of each of the available
physical
resources.
[0050] 4. The method as in any of the embodiments 1-3, comprising the
step of mapping at least one higher layer data flow to at least two H-ARQ
processes.
[0051] 5. The method of embodiment 4, comprising the step of
determining physical transmission parameters and H-ARQ configurations to
support QoS requirements of the higher layer data flow mapped to each H-ARQ
process.
[0052] 6. The method of embodiment 5, comprising the step of
generating TBs from the mapped higher layer data flow in accordance with the
physical transmission parameters and H-ARQ configurations of each H-ARQ
process, respectively.
[0053] 7. The method of embodiment 6, comprising the step of
transmitting the TBs via the H-ARQ processes simultaneously.
[0054] 8. The method as in any of the embodiments 5-7, wherein the
physical transmission parameters and H-ARQ configurations include a TFC for
each TB.
[0055] 9. The method as in any of the embodiments 2-8, wherein the
com.munication nodes include multiple antennas for MIMO and the available
physical resources are identified based on independent spatial data streams.
[0056] 10. The method as='in any of the embodiments 2-9, wherein the
available physical resources are identified based on independent frequency
subcarriers.
-13-
CA 02635874 2008-06-30
WO 2007/079058 PCT/US2006/049214
[0057] 11. The method of embodiment 10, wherein the subcarriers are
distributed subcarriers.
[0058] 12. The method of embodiment 10, wherein the subcarriers are
localized subcarriers.
[0059] 13. The method as in any of the embodiments 2-12, wherein the
available physical resources are identified based on independent
channelization
codes.
[0060] 14. The method as in any of the embodiments 2-13, wherein the
available physical resources are identified based on different time slots.
[0061] 15. The method as in any of the embodiments 2-14, wherein the
association of the physical resources and the H-ARQ processes is dynamically
determined.
[0062] 16. The method as in any of the embodiments 2-14, wherein the
association of the physical resources and the H-ARQ processes is semi-
statically
configured.
[0063] 17. The method as in any of the embodiments 4-16, further
comprising the step of selecting higher layer data flows to be transmitted in
a
next TTI, whereby only the selected higher layer data flows are mapped to the
H-
ARQ processes.
[0064] 18. The method of embodiment 17, wherein a packet on each
higher layer data flow is assigned a life span time, whereby the selection of
a
packet for transmission is made based on the life span time.
[0065] 19. The method as in any of the embodiments 5-18, wherein when
QoS requirements of the higher layer data flows are similar, the physical
transmission and H-ARQ configurations are determined such that QoS across the
available H-ARQ processes is similar.
[0066] 20. The method of embodiment 19, wherein a higher order MCS
is applied to an H-ARQ process with a higher channel quality and a lower order
MCS is applied to an H-ARQ process with a lower channel quality.
[0067] 21. The method as in any of the embodiments 19-20, wherein the
number of maximum retransmissions is assigned to each H-ARQ process based
-14-
CA 02635874 2008-06-30
WO 2007/079058 PCT/US2006/049214
on the QoS requirement of a higher layer data flow mapped to the H-ARQ
process.
[0068] 22. The method as in any of the embodiments 5-18, wherein when
QoS requirements of the higher layer data flows are not similar, each of the
higher layer data flows is mapped to an H-ARQ process associated with channel
quality that closely matches to a QoS requirement of the higher layer data
flow.
[0069] 23. The method as in any of the embodiments 5-18, wherein when
QoS requirements of the higher layer data flows are not similar, a maximum
number of retransmissions is assigned to an H-ARQ process based on the QoS
requirement of a higher layer data flow mapped to the H-ARQ process.
[0070] 24. The method as in any of the embodiments 2-23, wherein
physical resources mapped to the H-ARQ process are unchanged for
retransmission of a TB when transmission of the TB fails.
[0071] 25. The method of embodiment 24, wherein physical transmission
and H-ARQ configurations are changed for retransmission of the TB.
[0072] 26. The method of embociiment 24, wherein the TB is fragmented
for retransmission.
[0073] 27. The method as in any of the embodiments 2-23, wherein
physical resources mapped to the TB are changed for retransmission of the TB
when transmission of the TB fails.
[0074] 28. The method as'in any of the embodiments 1-27, wherein the
wireless communication system is an HSPA+ system.
[0075] 29. The method as in any of the embodiments 1-27, wherein the
wireless communication system is an LTE of a 3G wireless communication
system.
[0076] 30. The method asin any of the embodiments 2-29, wherein the
available physical resources and associated H-ARQ processes are determined at
the start of common TTI boundary.
[0077] 31. The method as in any of the embodiments 5-30, wherein the
physical transmission parameters include an MCS for each TB.
[0078] 32. The method of embodiment 31, wherein an MCS for each TB
-15-
CA 02635874 2008-06-30
WO 2007/079058 PCT/US2006/049214
is selected to differentiate QoS requirements of the TBs.
[0079] 33. The method of embodiment 31, wherein an MCS for each TB
is selected such that the QoS supported across the H-ARQ processes is similar.
[0080] 34. The method as in any of the embodiments 5-33, wherein the
physical transmission parameters include a transport block size for each TB.
[0081] 35. The method of embodiment 34, wherein a TB size for each TB
is selected to differentiate QoS requirements of the TBs.
[0082] 36. The method of embodiment 34, where a TB size for each TB is
selected such that the QoS supported across the H-ARQ processes is similar.
[0083] 37. An apparatus for transmitting multiple TBs in a TTI
simultaneously with multiple H-ARQ processes in a wireless communication
system.
[0084] 38. The apparatus of embodiment 37, comprising a plurality of H-
ARQ processes.
[0085] 39. The apparatus of embodiment 38, comprising a controller
configured to identify available physical resources and H-ARQ processes
associated with the available physical resources, map at least one higher
layer
data flow to at least two H-ARQ processes based on channel quality of each of
the
available physical resources and Qo.S requirements of the higher layer data
flows,
and determine physical transmission parameters and H-ARQ configurations to
support QoS requirements of the higher layer data flows mapped to each H-ARQ
process.
[0086] 40. The apparatus of embodiment 39, comprising a plurality of
multiplexing and link adaptation processors, each multiplexing and link
adaptation processor being associated with an H-ARQ process and being
configured to generate a TB from the higher layer data flow mapped to the
multiplexing and link adaptation processor in accordance with the physical
transmission parameters and H-ARQ configurations of each H-ARQ process.
[0087] 41. The apparatus of embodiment 40, wherein each multiplexing
and link adaptation process deterinines a TFC for the higher layer data flow
mapped.
-16-
CA 02635874 2008-06-30
WO 2007/079058 PCT/US2006/049214
[0088] 42. The apparatus as in any of the embodiments 39-41, wherein
the controller identifies the available physical resources based on
independent
spatial data streams generated by multiple antennas for MIMO.
[0089] 43. The apparatus as in any of the embodiments 39-42, wherein
the controller identifies the available physical resources based on
independent
subcarriers.
[0090] 44. The apparatus of embodiment 43, wherein the subcarriers are
distributed subcarriers.
[0091] 45. The apparatus of embodiment 43, wherein the subcarriers are
localized subcarriers.
[0092] 46. The apparatus as in any of the embodiments 39-45, wherein
the controller identifies the available physical resources based on
independent
channelization codes.
[0093] 47. The apparatus as in any of the embodiments 39-46, wherein
the available physical resources are identified based on different time slots.
[0094] 48. The apparatus as in any of the embodiments 39-47, wherein
the association of the physical resources and the H-ARQ processes is
dynamically
determined.
[0095] 49. The apparatus as in any of the embodiments 39-47, wherein
the association of the physical resources and the H-ARQ processes is semi-
statically configured.
[0096] 50. The apparatus as in any of the embodiments 39-49, wherein
the controller is configured to select at least one higher layer data flow to
be
transmitted in a next TTI and map only the selected higher layer data flow to
the
H-ARQ processes. -
[0097] 51. The apparatus of embodiment 50, wherein a packet on the
higher layer data flow is assigned a life span time, whereby the controller
selects
a packet for transmission based on the life span time.
[0098] 52. The apparatus as in any of the embodiments 39-51, wherein
when QoS requirements of the higher layer data flows are similar, the
controller
determines the physical transmission and H-ARQ configurations to normalize
-17-
CA 02635874 2008-06-30
WO 2007/079058 PCT/US2006/049214
QoS across the available H-ARQ processes.
[0099] 53. The apparatus of embodiment 52, wherein the controller
applies a higher order MCS to an H-ARQ process with a higher channel quality
and applies a lower order MCS to an H-ARQ process with a lower channel
quality.
[00100] 54. The apparatus'of embodiment 52, wherein the controller
assigns a maximum retransmission limit to each H-ARQ process based on the
QoS requirement of the higher layer data mapped to the H-ARQ process.
[001011 55. The apparatus as in any of the embodiments 39-51, wherein
when QoS requirements of the higher layer data are not similar, the controller
maps the higher layer data to an H7ARQ process associated with channel quality
that closely matches to the QoS requirement of the higher layer data.
[00102] 56. The apparatus as in any of the embodiments 39-51, wherein
when QoS requirements of the higher layer data are not similar, the controller
assigns a maximum retransmission limit to an H-ARQ process based on the QoS
requirement of the higher layer data mapped to the H-ARQ process.
[001031 57. The apparatus as in any of the embodiments 39-56, wherein
the controller assigns the same physical resources for retransmission of a TB
when transmission of the TB fails.
[00104] 58. The apparatus of embodiment 57, wherein the controller
changes physical transmission and H-ARQ configurations for retransmission of
the TB_
[00105] 59. The apparatus as in any of the embodiments 57-58, wherein
the controller fragments the TB for retransmission.
[00106] 60. The apparatus as in any of the embodiments 39-56, wherein
the controller changes physical resources for retransmission of a TB when
transmission of the TB fails.
[00107] 61. The apparatus as in any of the embodiments 37-60, wherein
the wireless communication system is an HSPA+ system.
[00108] 62. The apparatus as in any of the embodiments 37-60, wherein
the wireless communication system is an LTE of a 3G wireless communication
-18-
CA 02635874 2008-06-30
WO 2007/079058 PCT/US2006/049214
system.
[00109] 63. The apparatus as in any of the embodiments 39-62, wherein
the available physical resources and associated H-ARQ processes are determined
at the start of common TTI boundary.
[00110] 64. The apparatus as in any of the embodiments 39-63, wherein
the physical transmission parameters include an MCS for each TB.
[00111] 65. The apparatus of embodiment 64, wherein an MCS for each
TB is selected to differentiate QoS requirements of the TBs.
[00112] 66. The apparatus of embodiment 64, wherein an MCS for each
TB is selected such that the QoS supported across the H-ARQ processes is
similar. .
[00113] 67. The apparatus as in any of the embodiments 39-66, wherein
the physical transmission parameters include a transport block size for each
TB.
[001141 68. The apparatus of embodiment 67, wherein a TB size for each
TB is selected to differentiate QoS-requirements of the TBs.
[00115] 69.The apparatus of embodiment 67, where a TB size for each TB is
selected such that the QoS supported across the H-ARQ processes is similar.
[00116] Although the features and elements of the present invention are
described in the preferred embodiments in particular combinations, each
feature
or element can be used alone without the other features and elements of the
preferred embodiments or in various combinations with or without other
features
and elements of the present invention. The methods or flow charts provided in
the present invention may be implemented in a computer program, software, or
firmware tangibly embodied in a computer-readable storage medium for
execution by a general purpose computer or a processor. Examples of computer-
readable storage mediums include a read only memory (ROM), a random access
memory (RAM), a register, cache memory, semiconductor memory devices,
magnetic media such as internal hard disks and removable disks, magneto-
optical media, and optical media such as CD-ROM disks, and digital versatile
disks (DVDs).
-19-
CA 02635874 2008-06-30
WO 2007/079058 PCT/US2006/049214
[00117] Suitable processors include, by way of example, a general purpose
processor, a special purpose processor, a conventional processor, a digital
signal
processor (DSP), a plurality of mic'roprocessors, one or more microprocessors
in
association with a DSP core, a controller, a microcontroller, Application
Specific
Integrated Circuits (ASICs), Field Programmable Gate Arrays (FPGAs) circuits,
any other type of integrated circuit (IC), and/or a state machine.
[00118] A processor in association with software may be used to implement
a radio frequency transceiver for use in a wireless transmit receive unit
(WTRU),
user equipment (UE), terminal, base station, radio network controller (RNC),
or
any host computer. The WTRU may be used in conjunction with modules,
implemented in hardware and/or software, such as a camera, a video camera
module, a videophone, a speakerphone, a vibration device, a speaker, a
microphone, a television transceiver, a hands free headset, a keyboard, a
Bluetooth module, a frequency modulated (FM) radio unit, a liquid crystal
display (LCD) display unit, an organic light-emitting diode (OLED) display
unit,
a digital music player, a media player, a video game player module, an
Internet
browser, and/or any wireless local area network (WLAN) module.
-20-
