U.S. patent application number 14/239415 was filed with the patent office on 2014-07-31 for ack/nack feedback method in wireless communication system.
The applicant listed for this patent is Hong He, Yingyang Li, Chengjun Sun. Invention is credited to Hong He, Yingyang Li, Chengjun Sun.
Application Number | 20140211768 14/239415 |
Document ID | / |
Family ID | 47697565 |
Filed Date | 2014-07-31 |
United States Patent
Application |
20140211768 |
Kind Code |
A1 |
He; Hong ; et al. |
July 31, 2014 |
ACK/NACK FEEDBACK METHOD IN WIRELESS COMMUNICATION SYSTEM
Abstract
A method of ACK/NACK feedback in a wireless communication
system. The method includes determining, by a UE, a number of
public sub-frames, all of which are uplink sub-frame in PCC and any
SCC sub-frames of any radio frame in frame structure configurations
according to the frame structure configurations of the PCC and any
SCC, selecting, by the UE, a configuration, uplink sub-frames of
which merely include sub-frames corresponding to the determined
number of public sub-frames from existing seven kinds of frame
structure configurations, and feeding back, by the UE, to an eNB
ACK/NACK information corresponding to PDSCH in the SCC on the PCC
adopting a timing relationship between the PDSCH and the ACK/NACK
corresponding to the selected configuration.
Inventors: |
He; Hong; (Beijing, CN)
; Li; Yingyang; (Beijing, CN) ; Sun; Chengjun;
(Beijing, CN) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
He; Hong
Li; Yingyang
Sun; Chengjun |
Beijing
Beijing
Beijing |
|
CN
CN
CN |
|
|
Family ID: |
47697565 |
Appl. No.: |
14/239415 |
Filed: |
August 16, 2012 |
PCT Filed: |
August 16, 2012 |
PCT NO: |
PCT/KR2012/006517 |
371 Date: |
February 18, 2014 |
Current U.S.
Class: |
370/336 |
Current CPC
Class: |
H04L 5/0044 20130101;
H04L 5/14 20130101; H04L 5/0092 20130101; H04L 5/0094 20130101;
H04L 5/1469 20130101; H04L 1/1893 20130101; H04L 1/0034 20130101;
H04L 1/1854 20130101; H04L 5/001 20130101; H04W 72/0446 20130101;
H04L 5/0073 20130101; H04L 5/0055 20130101 |
Class at
Publication: |
370/336 |
International
Class: |
H04L 1/00 20060101
H04L001/00; H04W 72/04 20060101 H04W072/04 |
Foreign Application Data
Date |
Code |
Application Number |
Aug 15, 2011 |
KR |
201110270303.1 |
Claims
1. An Acknowledgement/Non Acknowledgement (NACK) feedback method in
a wireless communication system, the method comprising:
determining, by a User Equipment (UE), a number of public
sub-frames, all of which are uplink sub-frame in Primary Component
Carrier (PCC) and any Secondary Component Carrier (SCC) sub-frames
of any radio frame in frame structure configurations according to
the frame structure configurations of the PCC and any SCC;
selecting, by the UE, a configuration, uplink sub-frames of which
merely comprise sub-frames corresponding to the determined number
of public sub-frames from existing seven kinds of frame structure
configurations; and feeding back, by the UE, to an Evolved NodeB,
(eNB) ACK/NACK information corresponding to Physical Downlink
Shared Channel, (PDSCH) in the SCC on the PCC adopting a timing
relationship between the PDSCH and the ACK/NACK corresponding to
the selected configuration.
2. The method of claim 1, further comprising: feeding back, by the
UE, to the eNB the ACK/NACK information corresponding to the PDSCH
in the PCC on the PCC adopting the timing relationship between the
PDSCH and ACK/NACK corresponding to the selected configuration.
3. The method of claim 1, further comprising: feeding back, by the
UE, to the eNB the ACK/NACK information corresponding to the PDSCH
in the PCC on the PCC adopting the timing relationship between the
PDSCH and the ACK/NACK corresponding to the frame structure
configuration of the PCC.
4. The method of claim 2, wherein, when a bundled window of
downlink data sub-frames determined by the UE comprises uplink data
sub-frames, further comprising: mapping the ACK/NACK corresponding
to the uplink data sub-frames into a Discontinuous Transmission
(DTX) status, or not feeding back any ACK/NACK information.
5. The method of claim 1, wherein, when the UE is configured with
more than two PCCs, before determining, by the UE, the determined
number of public sub-frames, all of which are uplink sub-frame in
PCC and any SCC sub-frames of a radio frame in the frame structure
configurations, the method further comprises: notifying, by the
eNB, the UE of a number of PCC for feeding back the ACK/NACK
through Radio Resource Control (RRC), signaling.
6. The method of claim 1, wherein the selecting of, by the UE, the
configuration, uplink sub-frames of which merely comprise
sub-frames corresponding to the determined number of public
sub-frames from existing seven kinds of frame structure
configurations comprises: supposing that in any radio frame of the
frame structure configurations, a configuration including two
uplink and downlink sub-frame switching points is the configuration
of the first class and the other configurations are the
configurations of the second class, the two kinds of configurations
of UE are configuration A and configuration B; selecting, by the
UE, configuration B when configuration A and configuration B belong
to a same class of configuration, and proportion of uplink
sub-frames in configuration A is larger than that of configuration
B; selecting, by the UE, a configuration other than configuration 0
in configuration A and configuration B when configuration A and
configuration B do not belong to a same class of configuration, and
either of configuration A and configuration B is configuration 0;
selecting, by the UE, a configuration other than configuration 6 in
configuration A and configuration B when configuration A and
configuration B do not belong to a same class of configuration, and
neither of configuration A and configuration B is configuration 0
and either of them is configuration 6; selecting, by the UE,
configuration 5 when configuration A and configuration B do not
belong to a same class of configuration and either of configuration
A and configuration B is configuration 5; selecting, by the UE,
configuration 4 when (A, B) is (1, 3) or (1, 4); and selecting, by
the UE, configuration 5 when (A, B) is (2, 3) or (2, 4).
7. An Acknowledgement (ACK)/Non Acknowledgement (NACK) feedback
method in a wireless communication system, the method comprising:
notifying, by an Evolved NodeB (eNB), a User Equipment (UE) of
configured information of a Primary Component Carrier (PCC), and
all Secondary Component Carriers (SCC) through high-level
signaling, wherein the configured information of the PCC and all
SCCs of the UE comprises: a frame structure configuration of each
Component Carrier (CC) configured for the UE, and further
comprises: a number of the PCC and all SCCs; determining, by the
UE, a frame structure configuration according to the information of
the frame structure configurations of the PCC and all SCCs sent
from the eNB; and feeding back, by the UE, to the eNB, ACK/NACK
information corresponding to Physical Downlink Shared Channel
(PDSCH) in the SCCs on the PCC adopting a timing relationship
between the PDSCH and the ACK/NACK corresponding to the determined
frame structure configuration.
8. The method of claim 7, wherein, the determining of, by the UE,
the frame structure configuration according to the information of
the frame structure configurations of the PCC and all SCCs sent
from the eNB comprises: supposing that in any radio frame of the
frame structure configurations, a configuration including two
uplink and downlink sub-frame switching points is the configuration
of the first class and the other configurations are the
configurations of the second class, the two kinds of configurations
of UE are configuration A and configuration B; determining, by the
UE, configuration B when configuration A and configuration B belong
to a same class of configuration, and proportion of uplink
sub-frames in configuration A is larger than that of configuration
B; determining, by the UE, a configuration other than configuration
0 in configuration A and configuration B when configuration A and
configuration B do not belong to a same class of configuration, and
either of configuration A and configuration B is configuration 0;
determining, by the UE, a configuration other than configuration 6
in configuration A and configuration B when configuration A and
configuration B do not belong to a same class of configuration, and
neither of configuration A and configuration B is configuration 0
and either of them is configuration 6; determining, by the UE,
configuration 5 when configuration A and configuration B do not
belong to a same class of configuration and either of configuration
A and configuration B is configuration 5; determining, by the UE,
configuration 4 when (A, B) is (1, 3) or (1, 4); and determining,
by the UE, configuration 5 when (A, B) is (2, 3) or (2, 4).
9. The method of claim 7, further comprising: feeding back, by the
UE, to the eNB the ACK/NACK information corresponding to the PDSCH
in the PCC on the PCC adopting the timing relationship between the
PDSCH and ACK/NACK corresponding to the determined
configuration.
10. The method of claim 7, further comprising: feeding back, by the
UE, to the eNB the ACK/NACK information corresponding to the PDSCH
in the PCC on the PCC adopting the timing relationship between the
PDSCH and ACK/NACK corresponding to the frame structure
configuration of the PCC.
11. The method of claim 9, wherein, when a bundled window of
downlink data sub-frames determined by the UE comprises uplink data
sub-frames, further comprising: mapping the ACK/NACK corresponding
to the uplink data sub-frames into a Discontinuous Transmission
(DTX) status, or not feeding back any ACK/NACK information.
12. The method of claim 3, wherein, when a bundled window of
downlink data sub-frames determined by the UE comprises uplink data
sub-frames, further comprising: mapping the ACK/NACK corresponding
to the uplink data sub-frames into a Discontinuous Transmission
(DTX) status, or not feeding back any ACK/NACK information.
13. The method of claim 10, wherein, when a bundled window of
downlink data sub-frames determined by the UE comprises uplink data
sub-frames, further comprising: mapping the ACK/NACK corresponding
to the uplink data sub-frames into a Discontinuous Transmission
(DTX) status, or not feeding back any ACK/NACK information.
Description
TECHNICAL FIELD
[0001] The present invention relates to a field of mobile
communication technology, and more particularly, to an
Acknowledgement (ACK)/Non Acknowledgement (NACK) feedback method in
a wireless communication system.
BACKGROUND ART
[0002] In the 3.sup.rd Generation Partnership Project (3GPP) Long
Term Evolution (LTE) standard, a downlink transmission technology
is based on Orthogonal Frequency Division Multiplexing (OFDM) and
an uplink transmission technology is based on Single-Carrier
Frequency Division Multiple Access (SC-FDMA).
[0003] The LTE system uses two types of frame structure, i.e.,
frame structure type 1 adopting Frequency-Division Duplex (FDD) and
frame structure type 2 adopting Time Division Duplex (TDD). Frame
structure type 2 includes seven kinds of frame structure
configurations. The proportion of downlink sub-frames in each kind
of frame structure configuration is fixed, ranging from 40% to 90%.
As shown in FIG. 1, it can be clearly perceived from FIG. 1 that
each radio frame consists of 10 radio sub-frames, and numbered
sequentially from zero. Take configuration 0 for example:
[0004] Sub-frame 0 and sub-frame 5 are used for sending downlink
data, i.e., the sub-frame 0 and sub-frame 5 are used by the Evolved
NodeB (eNB) for sending information to the User Equipment (UE).
[0005] Sub-frames 2, 3 and 4 and sub-frames 7, 8 and 9 are used for
sending uplink data, i.e., the sub-frames 2, 3, 4, 7, 8 and 9 are
used by the UE for sending information to the eNB.
[0006] Sub-frame 1 and sub-frame 6 are known as special sub-frames,
consisting of three special time slots. The three special time
slots are respectively defined as Downlink Pilot Time Slot (DwPTS),
Guard Period (GP) and Uplink Pilot Time Slot (UpPTS). The length of
time of the DwPTS, GP, and UpPTS is variable. The specific value of
the length of the time is configured by the system. The special
sub-frames are used for sending the downlink data, and can be
regarded as truncated downlink sub-frames.
[0007] The subsequent evolution of the LTE system is known as the
"LTE-Advanced," called LTE-A for short. An objective of the LTE-A
is meeting system requirements of the International Mobile
Telecommunications (IMT)-Advanced advanced by the ITU. A critical
enhanced objective of the IMT-Advanced includes further enhanced
data rate, interoperability/compatibility with other systems and
worldwide roaming characteristics, etc. The objective of the data
rate for downlink is 1Gbps and the objective of the data rate for
uplink is 500Mbps.
[0008] Based on the above objectives, a concept of Carrier
Aggregation (CA) is introduced into LTE version 10. The spectral
efficiency of wireless resources is further improved by aggregating
multiple continuous or discontinuous carriers into system bandwidth
up to 100 Mhz and using the Multiple-Input Multiple-Output (MIMO)
technology applied in the LTE-A uplink and downlink. The system of
LTE version 10 is already able to meet the system requirements of
the IMT-Advanced. However, in the actual network deployment and
system operation, in most cases, competition of the spectrum and
scattered available spectrum makes such a large-scale continuous
spectrum aggregation unrealistic. In order to obtain the target
peak rate of the system of LTE version 10, in the future, the
system has to adopt the discontinuous spectrum allocation and
bandwidth aggregation. While the discontinuous spectrum aggregation
means that there are big differences between interferences of
different frequency bands. Especially for the network deployment of
the Time Division (TD)-LTE system, the interference between the
uplink and downlink severely restricts performances of the TD-LTE
system.
[0009] Based on the above analysis, in the future evolution of the
TD-LTE system, an important issue to be considered in the evolution
of the TD-LTE system is applying different frame structure
configurations to different Component Carriers (CC)s. In the system
of LTE Rel-10, when a UE is configured with multiple CCs, an eNB
notifies the UE of the number of the Primary Component Carrier
(PCC) and the number of aggregated Secondary Component Carriers
(SCC)s through high-level signaling. In addition, when the multiple
CCs configured for the UE are in different frequency bands, and the
frame structure configuration of at least one CC is different from
the frame structure of other CCs, how to design a timing
relationship between a downlink data sub-frame Physical Downlink
Shared Channel (PDSCH) and Uplink (UL) control information, and
more specifically how to feed back the ACK/NACK becomes a key issue
to be solved when the carrier aggregation between different bands
adopts different frame structure configurations.
DISCLOSURE OF INVENTION
Technical Problem
[0010] At present, on the basis of rational technical analysis, the
following two solutions are mainly adopted.
[0011] The first one is on the assumption that all UEs supporting a
carrier aggregation technology between different bands and
characteristics of different frame structure configurations
includes at least two Power Amplifiers (PA)s and Radio frequency
(RF) circuits. Specifically, refer to the feedback method described
in FIG. 2, i.e., when all CCs of the UE are in two different bands
and the frame structure configurations in either a different band
are the same, while the frame structure in different bands is
different, the eNB designates a CC for feeding back ACK/NACK
information for each UE in each band through the high-level
signaling. Each band continues to use an existing timing
relationship between the PDSCH and UL ACK/NACK in its band
according to each different frame structure configuration. Although
this method can successfully feed back the ACK/NACK information,
requires that all UEs supporting the carrier aggregation technology
between different bands and characteristics of different frame
structure configurations include at least two PAs, which greatly
increases the cost of the Rel-11 terminal and restricts the
realization and market of the Rel-11 products. Further, as for cell
edge users with limited power, the characteristics of Cubic Metric
(CM) needs to be considered when sending the UL ACK/NACK
information on multiple CCs, and the efficiency of the amplifier of
the UE needs to be further reduced, which inevitably deteriorates
the performances of the UL ACK/ANCK and even makes the UL ACK/ANCK
can not be correctly received for the cell edge users with
insufficient power.
[0012] Therefore, the problem of the above method leads to a second
method, i.e., merely sending the UL ACK/NACK information on a
single PCC to ensure that even low-end users with only one PA in
the Rel-11 system still can benefit from the carrier aggregation
technology between different bands with different frame structure
configurations, and continue to use the existing power control
mechanism of the UL ACK/NACK information. A typical method
includes: designing a new timing relationship between the PDSCH and
UL ACK/NACK for taking Load Balancing (LB) characteristics of the
UL ACK/NACK into account. Although this method can correctly feed
back the ACK/NACK on the basis of overcoming the problem of the
first method, the biggest concern is that the new timing
relationship between the PDSCH and UL ACK/NACK needs a scheduler to
use new scheduling policy for allocating and scheduling resources,
i.e., the method needs to change the existing scheduler
algorithms.
[0013] On the basis of the above analysis, the existing ACK/NACK
feedback technical solutions have different problems. Therefore,
finding a feasible timing relationship between the PDSCH and UL
ACK/NACK, i.e. how to feed back ACK/NACK becomes a primary
technical problem of the LTE evolution version 11 to be solved.
Solution to Problem
[0014] In view of this, embodiments of the present invention
provide an ACK/NACK feedback method in a wireless communication
system, by which the UE may adaptively feed back the ACK/NACK
according to the configured frame structure configuration of the
CC, the carrier aggregation between Bands of different frame
structure configurations is effectively supported and the
coexistence and performance optimization of different communication
systems is implemented without limiting the number of amplifiers of
the UE.
[0015] In order to achieve the above objective, the technical
solution of the present invention is accomplished in the following
way:
[0016] An ACK/NACK feedback method in a wireless communication
system includes:
[0017] determining, by a UE, number of public sub-frames, all of
which are uplink subframe in PCC and SCC sub-frames of any radio
frame in frame structure configurations according to the frame
structure configurations of the PCC and any SCC;
[0018] selecting, by the UE, a configuration, uplink sub-frames of
which merely include sub-frames corresponding to the determined
number of public sub-frames from existing seven kinds of frame
structure configurations; and
[0019] feeding back, by the UE, to a eNB ACK/NACK information
corresponding to PDSCH in the SCC on the PCC adopting a timing
relationship between the PDSCH and the ACK/NACK corresponding to
the selected configuration.
[0020] The method further includes: feeding back, by the UE, to the
eNB the ACK/NACK information corresponding to the PDSCH in the PCC
on the PCC adopting the timing relationship between the PDSCH and
ACK/NACK corresponding to the selected configuration.
[0021] The method further includes: feeding back, by the UE, to the
eNB the ACK/NACK information corresponding to the PDSCH in the PCC
on the PCC adopting the timing relationship between the PDSCH and
the ACK/NACK corresponding to the frame structure configuration of
the PCC.
[0022] When a bundled window of downlink data sub-frames determined
by the UE includes uplink data sub-frames, the method further
includes:
[0023] mapping the ACK/NACK corresponding to the uplink data
sub-frames into a Discontinuous Transmission, DTX, status, or not
feeding back any ACK/NACK in- formation.
[0024] When the UE is configured with more than two PCCs, before
determining, by the UE, the number of public sub-frames, all of
which are uplink sub-frame in PCC and any SCC sub-frames of a radio
frame in the frame structure configurations, the method further
includes: notifying, by the eNB, the UE of number of PCC for
feeding back the ACK/NACK through Radio Resource Control, RRC,
signaling.
[0025] The method for selecting, by the UE, a configuration, uplink
sub-frames of which merely include sub-frames corresponding to the
determined number of public sub-frames from existing seven kinds of
frame structure configurations includes:
[0026] supposing that in any radio frame of the frame structure
configurations, a configuration including two uplink and downlink
sub-frame switching points is the configuration of the first class
and the other configurations are the configurations of the second
class, the two kinds of configurations of UE are configuration A
and configuration B;
[0027] selecting, by the UE, configuration B when configuration A
and configuration B belong to a same class of configuration, and
proportion of uplink sub-frames in configuration A is larger than
that of configuration B;
[0028] selecting, by the UE, a configuration other than
configuration 0 in configuration A and configuration B when
configuration A and configuration B do not belong to a same class
of configuration, and either of configuration A and configuration B
is configuration 0;
[0029] selecting, by the UE, a configuration other than
configuration 6 in configuration A and configuration B when
configuration A and configuration B do not belong to a same class
of configuration, and neither of configuration A and configuration
B is configuration 0 and either of them is configuration 6;
[0030] selecting, by the UE, configuration 5 when configuration A
and configuration B do not belong to a class kind of configuration
and either of configuration A and configuration B is configuration
5;
[0031] selecting, by the UE, configuration 4 when (A, B) is (1, 3)
or (1, 4); and
[0032] selecting, by the UE, configuration 5 when (A, B) is (2, 3)
or (2, 4).
[0033] An ACK/NACK feedback method in a wireless communication
system includes:
[0034] notifying, by a eNB, a UE of configured information of a PCC
and all SCCs through high-level signaling; wherein the configured
information of the PCC and all SCCs of the UE includes: a frame
structure configuration of each CC configured for the UE, and
further inlcudes: number of the PCC and all SCCs;
[0035] determining, by the UE, a frame structure configuration
according to the information of the frame structure configurations
of the PCC and all SCCs sent from the eNB; and
[0036] feeding back, by the UE, to the eNB, ACK/NACK information
corresponding to PDSCH in the SCCs on the PCC adopting a timing
relationship between the PDSCH and the ACK/NACK corresponding to
the determined frame structure configuration.
[0037] The method for determining, by the UE, a frame structure
configuration according to the information of the frame structure
configurations of the PCC and all SCCs sent from the eNB
includes:
[0038] supposing that in any radio frame of the frame structure
configurations, a configuration including two uplink and downlink
sub-frame switching points is the configuration of the first class
and the other configurations are the configurations of the second
class, the two kinds of configurations of UE are configuration A
and configuration B;
[0039] determining, by the UE, configuration B when configuration A
and configuration B belong to a same class of configuration, and
proportion of uplink sub-frames in configuration A is larger than
that of configuration B;
[0040] determining, by the UE, a configuration other than
configuration 0 in configuration A and configuration B when
configuration A and configuration B do not belong to a same class
of configuration, and either of configuration A and configuration B
is configuration 0;
[0041] determining, by the UE, a configuration other than
configuration 6 in configuration A and configuration B when
configuration A and configuration B do not belong to a same class
of configuration, and neither of configuration A and configuration
B is configuration 0 and either of them is configuration 6;
[0042] determining, by the UE, configuration 5 when configuration A
and configuration B do not belong to a same class of configuration
and either of configuration A and configuration B is configuration
5;
[0043] determining, by the UE, configuration 4 when (A, B) is (1,
3) or (1, 4); and
[0044] determining, by the UE, configuration 5 when (A, B) is (2,
3) or (2, 4).
[0045] The method further includes: feeding back, by the UE, to the
eNB the ACK/NACK information corresponding to the PDSCH in the PCC
on the PCC adopting the timing relationship between the PDSCH and
ACK/NACK corresponding to the determined configuration.
[0046] The method further includes: feeding back, by the UE, to the
eNB the ACK/NACK information corresponding to the PDSCH in the PCC
on the PCC adopting the timing relationship between the PDSCH and
ACK/NACK corresponding to the frame structure configuration of the
PCC.
[0047] When a bundled window of downlink data sub-frames determined
by the UE includes uplink data sub-frames, the method further
includes:
[0048] mapping the ACK/NACK corresponding to the uplink data
sub-frames into a Discontinuous Transmission, DTX, status, or not
feeding back any ACK/NACK information.
[0049] In view of the above technical solutions, with the ACK/NACK
feedback method in the wireless communication system provided by
embodiments of the present invention, the UE determines the number
of public sub-frames, all of which are uplink sub-frames in the PCC
and SCC sub-frames of any radio frame according to the configured
frame structure configurations of the PCC and any SCC, selects the
configuration, the uplink frames of which merely include sub-frames
corresponding to the determined number of the public sub-frames
from the existing seven kinds of frame structure configurations,
and feeds back to the eNB the ACK/NACK information corresponding to
the PDSCH in the SCC on the PCC adopting the timing relationship
between the PDSCH and ACK/NACK corresponding to the selected
configuration. Alternatively, the eNB notifies the UE of the
configured information of the PCC and all SCCs through the
high-level signaling. The UE determines a frame structure
configuration according to the information of the frame structure
configurations of the PCC and all SCCs sent from the eNB, and feeds
back to the eNB the ACK/NACK information corresponding to the PDSCH
in the SCCs on the PCC using the timing relationship between the
PDSCH and ACK/NACK corresponding to the determined frame structure
configuration. Further, when the UE is configured with multiple
CCs, and the frame structure configuration of at least one CC is
different from the frame structure configurations of the other CCs,
the method of the present invention may adaptively select and
determine a timing relationship between the PDSCH and UL ACK/NACK
according to the configured frame structure configuration of the CC
without changing the existing algorithm of the scheduler, and feed
back the ACK/NACK information on the PCC. Therefore, the ACK/NACK
feedback method of the present invention may effectively support
the carrier aggregation between Bands of different frame structure
configurations and implement the coexistence and performance
optimization of different communication systems without limiting
the number of amplifiers of the UE.
ADVANTAGEOUS EFFECTS OF INVENTION
[0050] The ACK/NACK feedback method of the present invention may
effectively support the carrier aggregation between Bands of
different frame structure configurations and implement the
coexistence and performance optimization of different communication
systems without limiting the number of amplifiers of the UE.
BRIEF DESCRIPTION OF DRAWINGS
[0051] FIG. 1 is a schematic diagram illustrating frame structure
configurations of an existing TD-LTE system;
[0052] FIG. 2 is a scene schematic diagram illustrating an existing
ACK/NACK feedback method;
[0053] FIG. 3 is a work flow chart of ACK/NACK feedback method one
according to an embodiment of the present invention;
[0054] FIG. 4 is a scene schematic diagram illustrating a first
embodiment of the present invention for determining ACK/NACK
sub-frames;
[0055] FIG. 5 is a scene schematic diagram illustrating a second
embodiment of the present invention for determining ACK/NACK
sub-frames;
[0056] FIG. 6 is a scene schematic diagram illustrating a third
embodiment of the present invention for determining ACK/NACK
sub-frames;
[0057] FIG. 7 is a scene schematic diagram illustrating a fourth
embodiment of the present invention for determining ACK/NACK
sub-frames;
[0058] FIG. 8 is a scene schematic diagram illustrating a fifth
embodiment of the present invention for determining ACK/NACK
sub-frames; and
[0059] FIG. 9 is a work flow chart of ACK/NACK feedback method two
according to an embodiment of the present invention.
MODE FOR THE INVENTION
[0060] The present invention is further described in detail
hereinafter with reference to the accompanying drawings to make the
objective, technical solution and merits thereof more apparent.
[0061] The main idea of the present invention is:
[0062] UE determines number of public sub-frames, all of which are
uplink sub-frames in the PCC and SCC sub-frames of any radio frame
in the frame structure configurations according to the configured
frame structure configurations of the PCC and any SCC. The UE
selects a configuration, the uplink frames of which merely include
sub-frames corresponding to the determined number of the public
sub-frames, from the existing seven kinds of frame structure
configurations. The UE feeds back to the eNB the ACK/NACK
information corresponding to the PDSCH in the SCC on the PCC
adopting a timing relationship between the PDSCH and ACK/NACK
corresponding to the selected configuration.
[0063] Alternatively, the eNB notifies the UE of the configured
information of the PCC and all SCCs through high-level signaling.
The configured information of the PCC and all SCCs of the UE
includes the frame structure configuration of each CC configured
for the UE, and further includes the number of the PCC and all
SCCs. The UE determines a frame structure configuration according
to the information of the frame structure configurations of the PCC
and all SCCs sent from the eNB. The UE feeds back to the eNB the
ACK/NACK information corresponding to the PDSCH in the SCCs on the
PCC adopting the timing relationship between the PDSCH and ACK/NACK
corresponding to the determined frame structure configuration.
[0064] FIG. 3 illustrates a work flow of ACK/NACK feedback method
one according to an embodiment of the present invention. As shown
in FIG. 3, the flow includes:
[0065] Block 301: UE determines number of public sub-frames, all of
which are uplink sub-frames in the PCC and SCC sub-frames of any
radio frame in the frame structure configurations according to the
configured frame structure configurations of the PCC and any
SCC.
[0066] It should be noted that when the UE is configured with more
than two PCCs, the CC for feeding back the ACK/NACK is one of the
PCCs. Therefore, before executing this block, the eNB notifies the
UE of the number of the PCC used for feeding back the ACK/NACK
through the Radio Resource Control (RRC) signaling.
[0067] Block 302: The UE selects a configuration, the uplink frames
of which merely include sub-frames corresponding to the determined
number of the public sub-frames, from the seven kinds of existing
frame structure configurations.
[0068] The UE selects the configuration, the uplink frames of which
merely include sub-frames corresponding to the determined number of
the public sub-frames, i.e., selects the frame structure
configuration, in which the sub-frames except for the uplink
sub-frames, i.e. the sub-frames corresponding to the determined
number of the public sub-frames are downlink sub-frames. In this
block, the UE selecting the configuration, the uplink frames of
which merely include sub-frames corresponding to the determined
number of the public sub-frames, from the seven kinds of existing
frame structure configurations specifically includes:
[0069] Suppose that in the frame structure configuration and any
radio frame, the configuration including two uplink and downlink
sub-frame switching points is the configuration of the first class
and the other configurations are the configurations of the second
class. The two kinds of configurations of UE are configuration A
and configuration B.
[0070] When configuration A and configuration B belong to a same
class of configuration, and the proportion of the uplink sub-frames
in configuration A is larger than that of configuration B, the UE
selects configuration B.
[0071] When configuration A and configuration B do not belong to a
same class of configuration, and either of configuration A and
configuration B is configuration 0, the UE selects the
configuration other than the configuration 0 in configuration A and
configuration B.
[0072] When configuration A and configuration B do not belong to a
same class of configuration, neither of configuration A and
configuration B is configuration 0 and either of them is
configuration 6, the UE selects the configuration other than
configuration 6 in configuration A and configuration B.
[0073] When configuration A and configuration B do not belong to a
same class of configuration and either of configurations A and B is
configuration 5, the UE selects the configuration 5.
[0074] When (A, B) is (1, 3) or (1, 4), the UE selects the
configuration 4.
[0075] When (A, B) is (2, 3) or (2, 4), the UE selects the
configuration 5.
[0076] Table 1 shows the result of frame structure configurations
selected from the two different kinds of the frame structure
configurations. As shown in table 1, one is frame structure
configuration A, the other one is frame structure configuration B.
The UE finds existing configuration C which is backward compatible
frame structure configuration with the values of configuration A
and configuration B. Configuration C may be one of configuration A
and configuration B, or may be a new kind of frame structure
configuration.
TABLE-US-00001 TABLE 1 Frame structure configuration A 0 1 2 3 4 5
6 Frame 0 1 2 3 4 5 6 structure 1 1 2 4 4 5 1 configuration B 2 2 2
5 5 5 2 3 3 4 5 4 5 3 4 4 4 5 4 5 4 5 5 5 5 5 5 5 6 6 1 2 3 4 5
[0077] Block 303: The UE feeds back to the eNB the ACK/NACK
information corresponding to the PDSCH in the SCC on the PCC using
the timing relationship between the PDSCH and ACK/NACK
corresponding to the selected configuration.
[0078] It should be noted that in this block, for the PDSCH of the
PCC, two ACK/NACK feedback manners may be adopted. One is the same
as that of SCC, i.e., feeding back the ACK/NACK information on the
PCC according to the timing relationship between the PDSCH and
ACK/NACK corresponding to the selected configuration, That is, the
UE may feed back the ACK/NACK information corresponding to all
downlink data on a single CC, so that make the UL ACK/NACK obtained
by mapping the PCC and SCC exactly the same as the timing
relationship between the downlink data sub-frames. The other is
feeding back the ACK/NACK information on the PCC according to the
ACK/NACK timing relationship determined by its own frame structure
configuration.
[0079] It should be noted that, for any configured CC, when the
ACK/NACK information is fed back according to the timing
relationship between the PDSCH and ACK/NACK corresponding to the
selected configuration, and a bundled window of the downlink data
sub-frames determined by the UE includes the uplink data
sub-frames, the ACK/NACK corresponding to the uplink data
sub-frames are definitively mapped into a Discontinuous
Transmission (DTX) status, or not feeding back any ACK/NACK
information.
[0080] At this point, the whole work flow of ACK/NACK feedback
method one of the present invention is finished. In order to make
the method of the present invention more apparent, examples are
given hereafter for description.
Embodiment One
[0081] In this embodiment, suppose that the UE is configured with
two CCs, the number of which is CC0 and CC1. CC0 is PCC and CC1 is
SCC. Based on the consideration of minimized adjacent channel
interference, CC0 adopts frame structure configuration 1, while CC1
adopts frame structure configuration 2. Refer to the scene
schematic diagram shown in FIG. 4 for the method for determining
the ACK/NACK sub-frames. As shown in FIG. 4, the method
includes:
[0082] Step 401: The UE determines the number of uplink public
sub-frames, i.e. designates the number of the public uplink
sub-frames as sub-frame 2 and sub-frame 7 according to the frame
structure configurations of PCC and SCC.
[0083] Step 402: The UE selects the configuration, i.e., the frame
structure configuration 2 in Frame Structure 2 (FS2), the uplink
sub-frames of which merely include sub-frame 2 and sub-frame 7 from
the existing seven kinds of frame structure configurations
according to the result of step 401.
[0084] Step 403: The UE feeds back the ACK/NACK information for the
PCC and all SCCs adopting the timing relationship between the PDSCH
and ACK/NACK corresponding to the frame structure configuration 2
in the FS2.
[0085] It should be noted that in this embodiment, the PCC feeds
back the ACK/NACK information according to the timing relationship
between the PDSCH and ACK/NACK corresponding to the selected
configuration. Thus, the UL ACK/NACK obtained by mapping the PCC
and SCC is exactly the same as the timing relationship between the
downlink data sub-frames.
[0086] Specifically, in this embodiment, both the eNB and UE
definitely know that when specific sub-frames (the characteristics
are that in the configured CC, this sub-frame is the downlink
sub-frame of at least one CC, and meanwhile is the uplink sub-frame
of at least one CC, such as, sub-frames 3 and 8 in FIG. 4) in the
bundled window are uplink sub-frames of some CCs, the corresponding
ACK/NACK mapping of the specific sub-frames in the bundled window
is the DTC status.
Embodiment Two
[0087] In this embodiment, suppose that the UE is configured with
two CCs, the number of which is CC0 and CC1. CC0 is PCC and CC1 is
SCC. Based on the consideration of minimized adjacent channel
interference, CC0 adopts frame structure configuration 1, while CC1
adopts frame structure configuration 3. Refer to the scene
schematic diagram shown in FIG. 5 for the method for determining
the ACK/NACK sub-frames. As shown in FIG. 5, the method
includes:
[0088] Step 501: The UE determines the number of uplink public
sub-frames, i.e. designates the number of the public uplink
sub-frames as sub-frame 2 and sub-frame 3 according to the frame
structure configurations of PCC and SCC.
[0089] Step 502: The UE selects the configuration, i.e., the frame
structure configuration 4 in Frame Structure 2 (FS2), the uplink
sub-frames of which merely include sub-frame 2 and sub-frame 3 from
the existing seven kinds of frame structure configurations
according to the result of step 501.
[0090] Step 503: The UE feeds back the ACK/NACK information for the
PCC and all SCCs adopting the timing relationship between the PDSCH
and ACK/NACK corresponding to the frame structure configuration 4
in the FS2.
[0091] It should be noted that same as embodiment one, the PCC also
feeds back the ACK/NACK information according to the timing
relationship between the PDSCH and ACK/NACK corresponding to the
selected configuration.
[0092] Specifically, in this embodiment, both the eNB and UE
definitely know that when specific sub-frames (the characteristics
are that in the configured CC, this sub-frame is the downlink
sub-frame of at least one CC, and meanwhile is the uplink sub-frame
of at least one CC, such as, sub-frames 7 and 8 in FIG. 5) in the
bundled window are uplink sub-frames of some CCs, this embodiment
does not feed back any ACK/NACK information for the specific
sub-frames in the bundled window.
Embodiment Three
[0093] In this embodiment, suppose that the UE is configured with
two CCs, the number of which is CC0 and CC1. CC0 is PCC and CC1 is
SCC. Based on the consideration of minimized adjacent channel
interference, CC0 adopts frame structure configuration 2, while CC1
adopts frame structure configuration 4. Refer to the scene
schematic diagram shown in FIG. 6 for the method for determining
the ACK/NACK sub-frames. As shown in FIG. 6, the method
includes:
[0094] Step 601: The UE determines the number of uplink public
sub-frames, i.e. designates the number of the public uplink
sub-frames as sub-frame 2 according to the frame structure
configurations of PCC and SCC.
[0095] Step 602: The UE selects the configuration, i.e., the frame
structure configuration 5 in Frame Structure 2 (FS2), the uplink
sub-frames of which merely include sub-frame 2 from the existing
seven kinds of frame structure configurations according to the
result of step 601.
[0096] Step 603: The UE feeds back the ACK/NACK information for the
PCC and all SCCs adopting the timing relationship between the PDSCH
and ACK/NACK corresponding to the frame structure configuration 5
in the FS2.
[0097] Similarly, in this embodiment, both the eNB and UE
definitely know that when specific sub-frames (the characteristics
are that in the configured CC, this sub-frame is the downlink
sub-frame of at least one CC, and meanwhile is the uplink sub-frame
of at least one CC, such as, sub-frame 3 in FIG. 6) in the bundled
window are uplink sub-frames of some CCs, the corresponding
ACK/NACK mapping of the specific sub-frames in the bundled window
is the DTC status.
Embodiment Four
[0098] In this embodiment, suppose that the UE is configured with
two CCs, the number of which is CC0 and CC1. CC0 is PCC and CC1 is
SCC. Based on the consideration of minimized adjacent channel
interference, CC0 adopts frame structure configuration 2, while CC1
adopts frame structure configuration 4. Refer to the scene
schematic diagram shown in FIG. 7 for the method for determining
the ACK/NACK sub-frames. As shown in FIG. 7, the method
includes:
[0099] Step 701: The UE determines the number of uplink public
sub-frames, i.e. the sub-frame 2 in the figure according to the
frame structure configurations of the PCC and SCC.
[0100] Step 702: The UE selects the configuration, i.e., the frame
structure configuration 5 in Frame Structure 2 (FS2), the uplink
sub-frames of which merely include sub-frame 2 from the existing
seven kinds of frame structure configurations according to the
result of step 701.
[0101] Step 703: The UE merely feeds back the ACK/NACK information
for the SCC adopting the timing relationship between the PDSCH and
ACK/NACK corresponding to the frame structure configuration 5 in
the FS2. While the PCC still determines the timing relationship
between the PDSCH and ACK/NACK according to the frame structure
configuration of a real PCC.
[0102] It should be noted that in this embodiment, the PCC feeds
back the ACK/NACK information adopting its own frame structure
configuration.
[0103] Further, it should be noted that in this embodiment, both
the eNB and UE definitely know that when specific sub-frames (the
characteristics are that in the configured CC, this sub-frame is
the downlink sub-frame of at least one CC, and meanwhile is the
uplink sub-frame of at least one CC, such as, sub-frame 7 in FIG.
7) in the bundled window are uplink sub-frames of some CCs, this
embodiment does not feed back any ACK/NACK information for the
specific sub-frames in the bundled window.
Embodiment Five
[0104] In this embodiment, suppose that the UE is configured with
three CCs, respectively in different bands. Suppose that the number
of the three CCs is CC0 (in Band I), CC1 (in Band II) and CC2 (in
Band III). CC0 is PCC, CC1 is SCC0 and CC2 is SCC1. Based on the
consideration of minimized adjacent channel interference, CC0
adopts frame structure configuration 1, CC1 adopts frame structure
configuration 3 and CC2 adopts frame structure configuration 0.
Refer to the scene schematic diagram shown in FIG. 8 for the method
for determining the ACK/NACK sub-frames. As shown in FIG. 8, the
method includes:
[0105] Step 800: The UE respectively determines the timing
relationship between the PDSCH and ACK/NACK for each SCC with
different frame structure configuration according to the frame
structure configurations of the PCC, SCC0 and SCC1, which
specifically includes:
[0106] Step 801: The UE determines the number of uplink public
sub-frames as sub-frame 2 according to the frame structure
configurations of PCC and SCC0.
[0107] Step 802: The UE selects the configuration, i.e., the frame
structure configuration 4 in Frame Structure 2 (FS2), the uplink
sub-frames of which merely include sub-frame 2 and sub-frame 3 from
the existing seven kinds of frame structure configurations
according to the result of step 801.
[0108] Step 803: The UE determines the number of the uplink public
sub-frames as sub-frame 2, sub-frame 3, sub-frame 7 and sub-frame 8
according to the frame structure configurations of PCC and
SCC1.
[0109] Step 804: The UE selects the configuration, i.e., the frame
structure configuration 1 in Frame Structure 2 (FS2), the uplink
sub-frames of which merely include sub-frames 2, 3, 7 and 8 from
the existing seven kinds of frame structure configurations
according to the result of step 803.
[0110] Step 805: The UE merely adopts the timing relationship
between the PDSCH and
[0111] ACK/NACK corresponding to the frame structure configuration
determined in steps 802 and 804 for the SCCs. That is, the UE feeds
back the ACK/NACK information for SCC0 adopting the timing
relationship between the PDSCH and ACK/NACK corresponding to the
frame structure configuration 4 determined, and feeds back the
ACK/NACK information for SCC1 adopting the timing relationship
between the PDSCH and ACK/NACK corresponding to frame structure
configuration 1. But, the PCC sill determines the timing
relationship between the PDSCH and ACK/NACK according to its frame
structure configuration.
[0112] It should be noted that in the above embodiments, when the
UE is configured with more than two PCCs, the eNB notifies the UE
of the number of the PCC for feeding back the ACK/NACK through the
RRC signaling.
[0113] All the above embodiments are illustrating examples, in
actual application, the PCC not only can feed back the ACK/NACK
information according to the timing relationship between the PDSCH
and ACK/NACK corresponding to the selected configuration, but also
can feed back the ACK/NACK information according its own frame
structure configuration. Further, for the specific sub-frames in
the bundled window, the ACK/NACK corresponding to the uplink data
sub-frames can be definitely either mapped into the DTC status, or
not feeding back any ACK/NACK information.
[0114] Corresponding to the flow of method one shown in FIG. 3,
FIG. 9 shows a work flow of ACK/NACK feedback method two of the
present invention. As shown in FIG. 9, the flow includes:
[0115] Block 901: The eNB notifies UE of the configured information
of the PCC and all SCCs through high-level signaling. The
configured information of the PCC and all SCCs of the UE includes:
the frame structure configuration of each CC configured for the UE,
and further includes the number of the PCC and all SCCs.
[0116] Block 902: The UE determines a kind of frame structure
configuration according to the information of the frame structure
configurations of the PCC and all SCCs sent from the eNB.
[0117] In this block, the UE may uniquely determine a kind of
backward compatible frame structure configuration according to the
configured information of the CCs sent from the eNB. The UE
determines a kind of frame structure configurations as shown in
table 1 according to the information of the frame structure
configurations of the PCC and all SCCs sent from the eNB, which
specifically includes:
[0118] Suppose that in the information of the CC configured for the
UE and any radio frame, the configuration including two uplink and
downlink sub-frame switching points is the configuration of the
first class and the other configurations are the configurations of
the second class. The two kinds of configurations of UE are
configuration A and configuration B.
[0119] When configuration A and configuration B belong to a same
class of configuration, and the proportion of the uplink sub-frames
in configuration A is larger than that of configuration B,
configuration B is determined.
[0120] When configuration A and configuration B do not belong to a
same class of configuration, and either of configuration A and
configuration B is configuration 0, the configuration other than
the configuration 0 in configuration A and configuration B is
determined.
[0121] When configuration A and configuration B do not belong to a
same class of configuration, neither of configurations A and B is
configuration 0 and either of them is configuration 6, the
configuration other than the configuration 6 in configuration A and
configuration B is determined.
[0122] When configuration A and configuration B do not belong to a
same class of configuration and either of configurations A and B is
configuration 5, configuration 5 is determined.
[0123] When (A, B) is (1, 3) or (1, 4), configuration 4 is
determined.
[0124] When (A, B) is (2, 3) or (2, 4), configuration 5 is
determined.
[0125] Block 903: The UE feeds back to the eNB the ACK/NACK
information corresponding to the PDSCH in the SCCs on the PCC
adopting the timing relationship between the PDCH and ACK/NACK
corresponding to the determined frame structure configuration.
[0126] Further, the UE feeds back to the eNB the ACK/NACK
information corresponding to the PDSCH in the PCC on the PCC
adopting the timing relationship between the PDCH and ACK/NACK
corresponding to the determined configuration. Alternatively, the
UE feeds back to the eNB the ACK/NACK information corresponding to
the PDSCH in the PCC on the PCC adopting the timing relationship
between the PDCH and ACK/NACK corresponding to its own frame
structure configuration.
[0127] It should be noted that when the bundled window of the
downlink data sub-frames determined by the UE includes the uplink
data sub-frames, the ACK/NACK corresponding to the uplink data
sub-frames are definitively mapped into a DTX status, or not
feeding back any ACK/NACK information.
[0128] At this point, the whole work flow of ACK/NACK feedback
method of the present invention is finished.
[0129] In brief, with the ACK/NACK feedback method in the wireless
communication system provided by embodiments of the present
invention, the UE determines the number of public sub-frames, all
of which are uplink sub-frames in the PCC and SCC sub-frames of any
radio frame according to the configured frame structure
configurations of the PCC and any SCC, selects the configuration,
the uplink frames of which merely include sub-frames corresponding
to the determined number of the public sub-frames from the existing
seven kinds of frame structure configurations, and feeds back to
the eNB the ACK/NACK information corresponding to the PDSCH in the
SCC on the PCC adopting the timing relationship between the PDSCH
and ACK/NACK corresponding to the selected configuration.
Alternatively, the eNB notifies the UE of the configured
information of the PCC and all SCCs through the high-level
signaling. The UE determines a frame structure configuration
according to the information of the frame structure configurations
of the PCC and all SCCs sent from the eNB, and feeds back to the
eNB the ACK/NACK information corresponding to the PDSCH in the SCCs
on the PCC using the timing relationship between the PDSCH and
ACK/NACK corresponding to the determined frame structure
configuration.
[0130] Further, when the UE is configured with multiple CCs, and
the frame structure configuration of at least one CC is different
from the frame structure configurations of the other CCs, the
method of the present invention may adaptively select and determine
a timing relationship between the PDSCH and UL ACK/NACK according
to the configured frame structure configuration of the CC without
changing the existing algorithm of the scheduler, and feed back the
ACK/NACK information on the PCC. Therefore, the ACK/NACK feedback
method of the present invention may effectively support the carrier
aggregation between Bands of different frame structure
configurations and implement the coexistence and performance
optimization of different communication systems without limiting
the number of amplifiers of the UE.
[0131] The foregoing only describes preferred examples of the
present invention and is not used to limit the protection scope of
the present invention. Any modification, equivalent substitution
and improvement without departing from the spirit and principle of
the present invention are within the protection scope of the
present invention.
* * * * *