I 1111111111111111 1111111111 lllll lllll lllll 111111111111111 lll111111111111111
`
`US010498515B2
`
`c12) United States Patent
`Xu et al.
`
`(IO) Patent No.: US 10,498,515 B2
`(45) Date of Patent:
`Dec. 3, 2019
`
`(54) FEEDBACK INFORMATION PROCESSING
`METHOD, DEVICE AND SYSTEM
`
`(71) Applicant: ZTE CORPORATION, Shenzhen,
`Guangdong Province (CN)
`
`(72)
`
`Inventors: Jun Xu, Shenzhen (CN); YuNgok Li,
`Shenzhen (CN); Bo Dai, Shenzhen
`(CN); Yuxin Wang, Shenzhen (CN);
`Jin Xu, Shenzhen (CN)
`
`(73) Assignee: ZTE CORPORATION (CN)
`
`(52) U.S. Cl.
`CPC .......... H04L 510055 (2013.01); H04L 110003
`(2013.01); H04L 111812 (2013.01);
`(Continued)
`(58) Field of Classification Search
`CPC ... H04L 1/0003; H04L 1/0005; H04L 1/0011;
`H04L 1/0021; H04L 1/0026; H04L
`1/0028; H04L 1/0035; H04L 1/1671;
`H04L 1/1692; H04L 1/1812; H04L 1/20;
`H04L 1/203; H04L 5/0048; H04L 5/0055;
`H04L 5/0057; H04W 72/0446
`See application file for complete search history.
`
`( * ) Notice:
`
`Subject to any disclaimer, the term ofthis
`patent is extended or adjusted under 35
`U.S.C. 154(b) by 250 days.
`
`(56)
`
`References Cited
`
`U.S. PATENT DOCUMENTS
`
`(21) Appl. No.:
`
`15/306,763
`
`(22) PCT Filed:
`
`Aug. 11, 2014
`
`2015/0139009 Al*
`
`2015/0264704 Al*
`
`5/2015 Park .................. H04W 72/1231
`370/252
`9/2015 Park .................. H04W 72/1231
`370/329
`
`(86) PCT No.:
`
`PCT/CN2014/084120
`
`FOREIGN PATENT DOCUMENTS
`
`§ 371 (c)(l),
`(2) Date:
`
`Dec. 5, 2016
`
`(87) PCT Pub. No.: WO2015/165166
`
`PCT Pub. Date: Nov. 5, 2015
`
`(65)
`
`Prior Publication Data
`
`US 2017/0141903 Al May 18, 2017
`
`(30)
`
`Foreign Application Priority Data
`
`Apr. 30, 2014
`
`(CN) .......................... 2014 1 0182804
`
`(51)
`
`Int. Cl.
`H04L 5100
`H04L 1100
`
`(2006.01)
`(2006.01)
`(Continued)
`
`CN
`CN
`
`7/2009
`101478786 A
`5/2012
`102457969 A
`(Continued)
`
`Primary Examiner - Paul H Masur
`(74) Attorney, Agent, or Firm - McDonald Hopkins LLC
`
`ABSTRACT
`(57)
`The present document discloses a method, apparatus and
`system for processing feedback information. The method
`includes: the first transmission node receiving a signal of a
`data shared channel, and determining data transmission level
`indication information of a transport block according to the
`signal; and the first transmission node transmitting the data
`transmission level indication information corresponding to
`the transport block to a second transmission node.
`
`21 Claims, 8 Drawing Sheets
`
`I
`The first transmission node receives a signal of a data shared
`channel and determines data transmission level indication
`information of a transport block according to the signal
`
`101
`
`I
`1'
`The first transmission node transmits the data transmission
`level indication information corresponding to the transport block
`to a second transmission node
`
`102
`
`1
`
`APPLE 1015
`
`

`

`US 10,498,515 B2
`Page 2
`
`(51)
`
`Int. Cl.
`H04L 1118
`H04L 1120
`H04W72/04
`(52) U.S. Cl.
`CPC ............ H04L 11203 (2013.01); H04L 510048
`(2013.01); H04L 510057 (2013.01); H04W
`7210446 (2013.01)
`
`(2006.01)
`(2006.01)
`(2009.01)
`
`(56)
`
`References Cited
`
`FOREIGN PATENT DOCUMENTS
`
`CN
`CN
`EP
`WO
`WO
`
`103297181 A
`103369694 A
`2663007 Al
`2008021573 A2
`2008051466 A2
`
`9/2013
`10/2013
`11/2013
`2/2008
`5/2008
`
`* cited by examiner
`
`2
`
`

`

`U.S. Patent
`
`Dec. 3, 2019
`
`Sheet 1 of 8
`
`US 10,498,515 B2
`
`I
`The first transmission node receives a signal of a data shared
`channel and determines data transmission level indication
`information of a transport block according to the signal
`
`101
`
`,,
`I
`The first transmission node transmits the data transmission
`level indication information corresponding to the transport block
`to a second transmission node
`
`102
`
`FIG. 1
`
`I
`The UE determines HARQ acknowledgment information and error
`level indication information corresponding to each transport block
`according to the received signal of the downlink data shared channel
`
`201
`
`,,
`
`202
`
`I
`
`The UE transmits the HARQ acknowledgment information NACK
`and the error level indication infom1ation BCER to the base station
`through the PUSCH
`
`FIG. 2
`
`I
`The UE determines the HARQ acknowledgment information and
`error level indication information corresponding to each transport
`block based on the received signal of the downlink data shared channel
`
`301
`
`''
`The UE transmits the HARQ acknowledgment information NACK
`and the error level indication information to the base station
`on the nth subframe through the PUSCH
`
`302
`
`I
`
`FIG. 3
`
`3
`
`

`

`U.S. Patent
`
`Dec. 3, 2019
`
`Sheet 2 of 8
`
`US 10,498,515 B2
`
`I
`The UE determines the soft ACK/NACK infom1ation corresponding
`to each transmission according to the received signal of the
`downlink data shared channel
`
`401
`
`,,
`
`402
`
`I
`
`The UE transmits the soft ACK/NACK information
`to the base station through the PUCCH
`
`FIG.4
`
`/
`The UE determines the triggered channel quality indication information
`and the HARQ acknowledgement information corresponding to each
`transport block according to the received signal of the downlink data
`shared channel
`
`501
`
`,
`
`I
`The UE transmits the triggered channel quality indication
`infom1ation and the HARQ acknowledgn1ent infom1ation to
`the base station through the PUSCH
`
`502
`
`FIG. 5
`
`/ 601
`
`/
`
`The UE determines the joint-coded indication information of
`the triggered error level indication infonnation and the ACK
`acknowledgment information corresponding to each transport block
`according to the received signal of the downlink data shared channel
`
`,,
`// 602
`The tem1inal transmits the joint-coded indication information of the
`triggered error level indication information and the ACK
`acknowledgment information to the base station through the PUCCH
`
`FIG. 6
`
`4
`
`

`

`U.S. Patent
`
`Dec. 3, 2019
`
`Sheet 3 of 8
`
`US 10,498,515 B2
`
`/
`The UE detennines the triggered power parameter indication
`information and the HARQ acknowledgement infom1ation
`corresponding to each transport block according to the
`received signal of the downlink data shared channel
`
`/ 701
`
`,,
`
`/
`
`702
`
`The UE transmits the triggered power parameter indication
`information and the HARQ acknowledgment information to
`the base station through the PUSCH
`FIG. 7
`
`/
`The base station receives the triggered repetition number
`indication information and the HARQ acknowledgement
`information corresponding to each transport block according
`to the received signal of the downlink data shared channel
`
`/ 801
`
`,,
`The base station transmits the triggered repetition number indication
`information and the HARQ acknowledgment information to
`the terminal through the PUSCH
`FIG. 8
`
`./ 802
`
`/
`The base station detem1ines the data transmission level indication
`information corresponding to each transport block according to
`the received signal of the downlink data shared channel
`
`/ 901
`
`',
`If the base station generates the blind-detectable ACK information,
`the base station transmits the blind-detectable ACK infom1ation
`to the terminal through the physical downlink channel
`FIG. 9
`
`// 902
`
`5
`
`

`

`U.S. Patent
`
`Dec. 3, 2019
`
`Sheet 4 of 8
`
`US 10,498,515 B2
`
`/
`The second transmission node receives data transmission level
`indication infom1ation of a transport block transmitted by a first
`transmission node
`
`1001
`
`/
`The second transmission node detennines a Modulation and Coding
`Scheme (MCS) or a retransmission number of the data information
`according to the data transmission level indication information
`
`1002
`
`,,
`
`/
`1'
`Modulation and coding is performed on the data information using
`the determined MCS to acquire bits of the data infom1ation, and
`the bits of the data infom1ation are transmitted to the first
`transmission node
`
`1003
`
`FIG. 10
`
`1101
`
`/
`
`The base station receives the data transmission level indication
`information of the transport block transmitted by the terminal
`
`/
`The base station determines the MCS of the data infom1ation
`according to the data transmission level indication information
`
`/ 1102
`
`,,
`
`FIG. 11
`
`6
`
`

`

`U.S. Patent
`
`Dec. 3, 2019
`
`Sheet 5 of 8
`
`US 10,498,515 B2
`
`An initial SINRO is predicted based on the CQI infonnation
`
`1201
`
`/
`
`',
`/
`In a first adjustment period T 1, adjustment of a first time is performed on the SINRO
`according to the HARQ acknowledgment information in the data transmission level
`indication information to acquire SINRl as SINRO after the adjustment of the first time
`
`1202
`
`',
`/
`In a second adjustment period T2, adjustment of a second time is performed on the
`SINR0 according to the error level indication information or the triggered channel
`quality indication information in the data transmission level indication infom1ation
`to acquire SINR2
`
`1203
`
`,,
`
`/
`The modulation and coding scheme of the transport block is detem1ined according
`to the SINR2 acquired after the adjustment of the second time and in accordance
`with a preset correspondence table between SINRs and MCSs
`FIG. 12
`
`1204
`
`/
`
`,.....1301
`
`Receiving
`module
`
`1304
`
`, /
`
`-
`-
`
`Calculation
`module
`
`,,
`- Determination
`-
`
`1302
`
`/
`
`module
`
`FIG. 13
`
`q,o3
`
`~ Transmission
`-
`module
`
`7
`
`

`

`U.S. Patent
`
`Dec. 3, 2019
`
`Sheet 6 of 8
`
`US 10,498,515 B2
`
`-CK1NACK
`
`CK/NACK
`
`ACK/NACKt
`
`•
`
`lts = SlNROu -
`1'iSINR16
`
`HARQ
`Transmission
`
`1 ~t HARQ Process
`
`2st HARQ Process
`
`•••••
`
`•••••
`
`t
`
`4
`
`5
`
`6
`
`c:)
`
`7
`
`t8
`
`t
`
`•••••
`
`ErrLevel14
`
`EITLevelrs
`
`FIG. 14
`
`8
`
`

`

`"'""' UI = N
`
`tit
`00
`\0
`"'""' = ~
`d r.,;_
`
`0 ....
`-....J
`.....
`rJJ =(cid:173)
`
`('D
`('D
`
`QO
`
`N
`~
`~
`
`~
`
`0 ....
`
`1,0
`
`c ('D
`
`~ = ~
`
`~
`~
`~
`•
`00
`
`e •
`
`Transmission
`
`module
`
`1503
`
`/
`
`sub-module
`
`Selection
`
`15024
`
`/
`
`FIG. 15
`
`Determination module
`
`15023
`
`1502
`
`/
`
`sub-module
`adjustment
`
`Second
`
`sub-module --
`
`First adjustment!
`
`15022
`
`/
`
`sub-module -
`
`Acquisition
`
`/
`15021
`
`module
`Receiving
`L
`1501
`
`9
`
`

`

`U.S. Patent
`
`Dec. 3, 2019
`
`Sheet 8 of 8
`
`US 10,498,515 B2
`
`The base station transmits a measurement reference signal to the terminal
`
`The tem1inal perfonns measurement according to the measurement
`reference signal to acquire a CQI of a downlink channel
`
`The terminal UE detem1ines the data transmission level indication information
`corresponding to each transport block according to the received signal of
`the downlink data shared channel
`
`and the CQI information to the base station through the physical uplink
`control channel
`
`The base station receives the data transmission level indication information
`and the CQI information con-esponding to one transport block transmitted
`by the tenninal
`
`The base station acquires a predicted signal to noise
`ratio according to the CQI transmitted by the terminal
`
`The base station adjusts the predicted signal to noise ratio according
`to the HARQ acknowledgment information transmitted by the terminal
`
`The base station adjusts the predicted STNR2 according to the error 1eve1
`indication infonnation or the triggered channel quality indication infonnation
`
`J
`
`J
`
`J
`J
`
`•
`+
`•
`The terminal UE reports the data transmission level indication information J
`'
`J
`•
`+
`•
`+
`
`J
`
`The base station allocates N PRB subbands to the
`tem1inal according to the SINR2 and a fairness factor
`
`'
`•
`•
`If
`'
`The base station transmits TBS bits to the user on the allocated N_PRB physical J
`
`The base station determines all possible TBSs under the N _PRB
`according to the N_PRB and an N_PRB and I_MCS to the TBS table
`
`The base station traverses all possible TBSs, and acquires the BLERs
`corresponding to all TBSs according to a link level curve and the impact of
`the TBS on the perfom1ance
`
`If
`
`A TBS when the BLER is closest to and less than the target BLER=O.l and
`a corresponding I_MCS are determined, the TBS is allocated to the user
`
`resource blocks according to the modulation and coding mode indicated
`by the I_MCS
`
`FIG. 16
`
`1601
`
`1602
`
`1603
`
`1604
`
`1605
`
`1606
`
`1607
`
`1608
`
`1609
`
`1610
`
`1611
`
`1612
`
`1613
`
`10
`
`

`

`US 10,498,515 B2
`
`1
`FEEDBACK INFORMATION PROCESSING
`METHOD, DEVICE AND SYSTEM
`
`TECHNICAL FIELD
`
`The present document relates to control teclmologies in
`the field of mobile communications, and in particular, to a
`method, apparatus and system for processing feedback
`information.
`
`BACKGROUND
`
`Long Term Evolution (LTE) projects are the evolution of
`3G. LTE is not a 4G teclmology which is commonly
`misunderstood by people, and instead, it is a transition
`between 3G and 4G teclmologies. LTE is a 3.9G global
`standard, and uses OFDM and MIMO as an unique standard
`of its wireless network evolution, which improves and
`enhances the 3G air access teclmology. This teclmology with
`the OFDM/FDMA as a core teclmology can be treated as a
`"quasi-4G" teclmology. In a spectral bandwidth of 20 MHz,
`it can provide a peak rate of 100 Mbit/s in the downlink and
`a peak rate of 50 Mbit/s in the uplink, which improves the
`performance for users at a cell edge, enhances a cell capacity
`and reduces system latency.
`The performance of the wireless system depends on a
`time-varying condition of a wireless link, which means that,
`for example, Block Error Ratio (BLER), throughput and
`delay are not constant. In order to deal with the changing
`condition of the wireless link and provide a reliable QOS, it
`is necessary to select an appropriate scheduling strategy. A
`processing mechanism of achieving dynamic adjustment is
`link adaptation. Generalized link adaptation includes inner
`loop link adaptation and outer loop link adaptation, HARQ
`and resource scheduling for matching channels etc.
`The Inner Loop Link Adaption (ILLA) is mainly based on
`a Signal to Interference ratio (SINR). For this approach, a
`reasonable SINR threshold is set for each supported modu(cid:173)
`lation and coding scheme, which requires consistency with
`the UE capability. Specifically, a terminal provides a CQI to
`a base station and the base station selects a MCS based on
`the CQI which is fed back.
`The purpose of the Outer Loop Link Adaption (OLLA) is
`to maintain a packet loss rate to be above a fixed level by
`dynamic adaptive
`thresholds, except
`that differences
`between these thresholds remain the same. The base station
`may assign a specific offset value to a terminal, which can
`be used to adjust a predicted SINR value.
`Since the transmission power in the LTE downlink is
`constant, the LTE employs different link adaptation tech- 50
`nologies in order to accommodate rapid changes in the radio
`channel. Firstly, the Modulation and Coding Scheme (MCS)
`adapts to the channel quality at some frequency intervals
`based on feedback from a User Equipment (UE). Secondly,
`an evolved base station (eNodeB) has a capability of per(cid:173)
`forming Frequency Domain Packet Scheduling (FDPS) to
`allocate the most suitable resources to the user. The purpose
`of Link Adaptation (LA) is to process the resulting feedback
`information from the terminal and then to select an appro(cid:173)
`priate MCS based on the information on a location of
`allocation in the frequency domain.
`In Long Term Evolution (LTE) and Long Term Evolution
`Advanced (LTE-A) systems, the link adaptation adopts a
`method of combining inner loop link adaptation and outer
`loop adaptation. The ILLA is firstly responsible for selecting
`an appropriate MCS for the UE. This selection is based on
`a mapping relationship between a measured SINR and an
`
`5
`
`2
`allocated optimum MCS. The ILLA does not always adapt
`well to the channel (for example, rapid channel change) for
`a variety ofreasons. Therefore, the function of the OLLA is
`also necessary. The purpose of the OLLA is to achieve a
`target BLER by adjusting the MCS selection. For example,
`the target BLER=0.1 in the LTE, and the base station can
`determine a current BLER by statistically analyzing HARQ
`ACKs fed back by the UE. Therefore, this method is based
`on Hybrid Automatic Repeat Request (HARQ)-ACK feed-
`IO back information for first HARQ transmission.
`In the LTE and LTE-A, the HARQ is a scheme of
`combining the ARQ and the FEC to retransmit only data
`packets with errors. The HARQ teclmology can well com-
`15 pensate for the influences of time variation and multipath
`fading of the wireless mobile channel on signal transmis(cid:173)
`sion, and has become one of indispensable key teclmologies
`in the system. The HARQ uses an incremental redundancy
`retransmission mechanism, and for each transmitted data
`20 packet, a complementary deletion manner is adopted. Vari(cid:173)
`ous data packets can not only be decoded individually, but
`also can be combined into a coded packet with more
`redundant information and decoded as a whole. The system
`can support a plurality of HARQ processes simultaneously,
`25 and one HARQ process corresponds to one transport block.
`On the base station side, a CRC is firstly added to one
`transport block, which is then coded and modulated to form
`a stream of code words. One stream of code words is
`mapped to one or more layers, and is then mapped to a
`30 plurality of OFDMA sub-carriers, which are subsequently
`processed and are transmitted to a terminal through an air
`interface. On the terminal side, it is firstly judged whether
`the received stream of code words is first transmitted data or
`retransmitted data of the transport block. If it is first trans-
`35 mitted data, the stream of code words is directly decoded, if
`it is decoded correctly, ACK is generated, and if it is decoded
`wrongly, NACK is generated. Otherwise, data of the last
`code word and data of the currently received code word in
`an HARQ buffer are combined, and are then decoded. If it
`40 is decoded correctly, ACK is generated, and if it is decoded
`wrongly, NACK is generated. The generated ACK or NACK
`is referred to as HARQ-ACK acknowledgement informa(cid:173)
`tion, and the terminal feeds back the acknowledgement
`information to the base station. On the base station side, if
`45 the acknowledgment information is ACK, it indicates that
`transmitted successfully. If the
`the transport block is
`acknowledgment information is NACK, it indicates that the
`transport block fails to be transmitted and a retransmission
`packet is required to be transmitted.
`In the LTE and LTE-A, for control signaling required to
`be transmitted in the uplink, there are ACK/NACK and three
`forms which reflects downlink physical Channel State Infor(cid:173)
`mation (CSI), which are Channels quality indication (CQI),
`a Pre-coding Matrix Indicator (PMI), and a Rank Indicator
`55 (RI).
`The CQI plays a key role in the link adaptation process,
`and is a message transmitted by the UE to the eNodeB for
`describing a current downlink channel quality of the UE.
`The UE may measure a reference symbol transmitted by the
`60 base station, and then calculate the CQI.
`The CQI is an index used to evaluate whether the down(cid:173)
`link channel quality is good or bad. In the 36-213 protocol,
`the CQI is represented using an integer value within a range
`of O to 15, which represents different CQI levels respec-
`65 tively. Different CQis correspond to respective MCSs, as
`shown in Table 1. The selection of the CQI level should
`follow the following criteria:
`
`11
`
`

`

`US 10,498,515 B2
`
`3
`the selected CQI level should enable a block error rate of
`a PDSCH transport block corresponding to the CQI under a
`corresponding MCS not to exceed 0.1.
`Based on a non-limited detection interval in the frequency
`domain and the time domain, the UE will obtain the highest 5
`CQI value, corresponding to each of the maximum CQI
`values transmitted in an uplink subframe n, the CQI serial
`numbers range from 1 to 15, and satisfy the following
`condition: an error rate BLER of a single PDSCH transport
`block is not more than 0.1 when the transport block is 10
`received, if CQI serial number 1 does not satisfy the
`condition, the CQI serial number is 0. The PDSCH transport
`block contains combined information, i.e. a modulation
`scheme and a transport block size, which corresponds to a
`CQI serial number and a set of occupied downlink physical 15
`resource blocks, i.e. CQI reference resources. Herein, the
`highest CQI value means a maximum CQI value which
`ensures that the BLER is not more than 0.1, this is beneficial
`for controlling the resource allocation. In general, the
`smaller the CQI value is, the more the resources are occu- 20
`pied, and the better the performance of the BLER is. Herein,
`the BLER is the error rate of the transport block, and the
`BLER is equal to the number of correctly transmitted TBs
`divided by the total number of transmitted TBs.
`For the combined information having the transport block 25
`size and the modulation scheme which corresponds to a CQI
`sequence number, according to the related transport block
`size, the combined information for PDSCH transmission in
`the CQI reference resources can be notified using signaling,
`and additionally:
`the modulation scheme is represented by the CQI serial
`number and uses the combined information including the
`transport block size and the modulation scheme in the
`reference resources, an effective channel coding rate gener(cid:173)
`ated by it is the most likely close effective channel coding 35
`rate which can be represented by the CQI serial number.
`When there is more than one piece of combined information
`and they can all generate equally close effective channel
`coding rates represented by the CQI serial number, com(cid:173)
`bined information with the smallest transport block size is 40
`used.
`Each CQI serial number corresponds to a modulation
`scheme and a transport block size. A correspondence rela(cid:173)
`tionship between transport block size and NPRB is shown in
`Table 1. A coding rate can be calculated according to the 45
`transport block size and a size of the NPRB.
`
`4
`There are many CQI definitions in the LTE, and the CQI
`can be divided according to different principles:
`according to a measurement bandwidth, the CQI is
`divided into a wideband CQI and a subband CQI;
`the wideband CQI refers to channel state indications of all
`the subbands, and CQI information of a subband set S is
`obtained;
`the subband CQI refers to CQI information for each
`subband. In the LTE, according to different system band(cid:173)
`widths, RBs corresponding to an effective bandwidth are
`divided into a number of RB groups, and each RB group is
`referred to as a subband.
`The subband CQI can also be divided into an all subband
`CQI and a Best M CQI. For the all subband CQI, CQI
`information of all subbands is transmitted; and for the Best
`M CQI, M sub bands are selected from the sub band set Sand
`CQI information of the M subbands is transmitted while
`location information of the M sub bands is transmitted.
`According to the number of code streams, the CQI is
`divided into a single-stream CQI and a dual-stream CQI.
`The single-stream CQI is applied in single-antenna trans(cid:173)
`mitting port 0, port 5, transmit diversity, MU-MIMO, and
`closed-loop spatial multiplexing with RI=l, and at this time,
`the UE transmits CQI information of a single code stream.
`The dual-stream CQI is applied in a closed-loop spatial
`multiplexing mode. For an open-loop spatial multiplexing
`mode, CQis of two code streams are equal in the open-loop
`spatial multiplexing since channel state information is
`unknown and double-stream characteristics are equalized in
`the precoding.
`According to a CQI representation method, the CQI is
`divided into an absolute value CQI and a differential CQI.
`The absolute value CQI is a CQI index represented by 4
`bits in Table 1; and the differential CQI is a CQI index
`represented by 2 bits or 3 bits. The differential CQI is further
`divided into a differential CQI of a second code stream with
`respect to a first code stream and a differential CQI of a
`subband CQI with respect to a subband CQI.
`According to a CQI transmission scheme, the CQI is
`divided into a wideband CQI, a UE selected (subband CQI),
`and a high layer configured (subband CQI); the wideband
`CQI refers to CQI information of a subband set S; the UE
`selected (subband CQI) is a Best M CQI, CQI information
`50 of selected M sub bands is fed back while positions of the M
`subbands are transmitted; and the high layer configured
`(subband CQI) is an all subband CQI, one piece of CQI
`information is fed back for each subband.
`
`30
`
`TABLE 1
`
`4-bit C I table
`
`CQI index
`
`modulation
`
`code rate x 1024
`
`efficiency
`
`0
`
`2
`3
`4
`5
`6
`7
`8
`9
`10
`11
`12
`13
`14
`15
`
`QPSK
`QPSK
`QPSK
`QPSK
`QPSK
`QPSK
`16QAM
`16QAM
`16QAM
`64QAM
`64QAM
`64QAM
`64QAM
`64QAM
`64QAM
`
`out of range
`78
`120
`193
`308
`449
`602
`378
`490
`616
`466
`567
`666
`772
`873
`948
`
`0.1523
`0.2344
`0.3770
`0.6016
`0.8770
`1.1758
`1.4766
`1.9141
`2.4063
`2.7305
`3.3223
`3.9023
`4.5234
`5.1152
`5.5547
`
`55
`
`60
`
`Both of the high layer configured and the UE selected are
`subband CQI feedback modes. In a non-periodic feedback
`mode, subband sizes defined by these two feedback modes
`are inconsistent. In the UE selected mode, a size of M is also
`defined.
`In the LTE system, an ACK/NACK response message is
`transmitted on a Physical Uplink Control Channel (PUCCH)
`in a format 1/la/lb (PUCCH format 1/la/lb), and ifa User
`Equipment (UE) needs to transmit uplink data, it is trans-
`65 mitted on a Physical Uplink Shared Channel (PUSCH). The
`feedback of the CQI/PMI and the RI may be periodic or
`non-periodic. A specific feedback is shown in Table 2.
`
`12
`
`

`

`US 10,498,515 B2
`
`5
`TABLE 2
`
`Uplink physical channels corresponding to periodic feedback
`and aperiodic feedback
`
`Scheduling mode
`
`Periodic CQI reporting
`channel
`
`Aperiodic CQI reporting
`channel
`
`Frequency
`non-selective
`Frequency
`selective
`
`PUCCH
`
`PUCCH
`
`PUSCH
`
`15
`
`6
`(LTE-A) system is an evolved standard of the LTE, which
`supports a greater system bandwidth (up to 100 MHz) and
`is backward compatible with the existing standard of the
`LTE. In order to achieve higher average spectral efficiency
`5 of a cell and improve the coverage and throughput at a cell
`edge, on the basis of the existing LTE system, in the Rel-10
`and Rel-11 releases, the LTE-A supports key technologies in
`the downlink such as SU/MU-MIMO dynamic switching of
`at most 8 antennas, Carrier Aggregation (CA), Coordinated
`10 Multi-point (COMP) transmission, Enhanced Inter-Cell
`Interference Coordination
`( eICIC),
`advanced Relay,
`enhanced PDCCH etc.
`In addition, in Release 10 of the LTE, in order to further
`enhance multi-antenna transmission in the downlink, a new
`transmission mode of closed-loop spatial multiplexing is
`added, which is defined as transmission mode 9, and DCI
`format 2C is added in the downlink control information to
`support such transmission mode. This transmission mode
`can not only support single-user SU-MIMO, but also can
`20 support multi-user MU-MIMO, and can support dynamic
`switching therebetween. In addition, this transmission mode
`also supports 8-antenna transmission. This new transmission
`mode has determined to use a demodulation pilot (UE
`Specific Reference Signal (URS for short)) as a pilot for
`demodulation, and the UE can estimate a channel and
`interference on the pilot only by acquiring a location of the
`pilot.
`Further, in Release 11 of the LTE, on the basis of the
`transmission mode 9, in order to further support the COMP
`transmission, transmission mode 10 is defined and DCI
`format 2D is added in the downlink control information to
`support this transmission mode.
`In the Rll release, the UE is semi-statically configured
`through high-level signaling to receive PDSCH data trans(cid:173)
`mission according to an indication of a PDCCH of a
`VE-specific search space based on one of the following
`transmission modes:
`Transmission mode 1: Single antenna port; Port 0
`Transmission mode 2: Transmit diversity
`Transmission Mode 3: Open-loop spatial multiplexing
`Transmission Mode 4: Closed-loop spatial multiplexing
`Transmission Mode 5: Multi-user MIMO
`Transmission mode 6: Closed-loop Rank=! precoding
`Transmission mode 7: single antenna port; port 5
`Transmission mode 8: dual-stream transmission, that is,
`dual-stream beamforming
`Transmission mode 9: up to 8 layer transmission
`Transmission mode 10: Support up to 8 layer transmission
`of COMP
`The Machine Type Communication (MTC for short) User
`Equipment (user device or terminal for short), which is also
`known as Machine to Machine (M2M for short) user com(cid:173)
`munication device, is a main application form of the current
`Internet of Things. In recent years, due to the high spectral
`efficiency of the Long-Term Evolution (LTE for short) or
`Long-Term Evolution Advanced (LTE-Advance or LTE-A
`for short), more and more mobile operators select the
`LTE/LTE-A as an evolution direction of broadband wireless
`communication systems. Based on the MTC of the LTE/
`LTE-A, various types of data services will also be more
`attractive.
`In the MTC application terminal, there is a class of
`terminals having a significant reduction in coverage perfor(cid:173)
`mance due to limitations of their locations or their own
`65 characteristics. For example, MTC terminals such as intel(cid:173)
`ligent meter reading are mostly installed in low-coverage
`performance environments such as a basement, and they
`
`Herein, for the CQI/PMI and the RI which are fed back
`periodically, if the UE does not need to transmit the uplink
`data, the CQI/PMI and the RI which are fed back periodi-
`cally are transmitted on the PUCCH in a format 2/2a/2b
`(PUCCH format 2/2a/2b ), and if the UE needs to transmit
`the uplink data, the CQI/PMI and the RI are transmitted on
`the PUSCH. For the CQI/PMI and the RI which are fed back
`aperiodically, they are only transmitted on the PUSCH.
`The Release 8 standard of the Long Term Evolution (LTE
`for short) defines three downlink physical control channels
`as follows: a Physical Control Format Indicator Channel
`(PCFICH for short), a Physical Hybrid Automatic Retrans(cid:173)
`mission Request Indicator Channel (PRICH for short), and 25
`a Physical Downlink Control Channel (PDCCH for short).
`Herein, the PDCCH is used for carrying Downlink Control
`Information (DCI for short), including: uplink and downlink
`scheduling information, and uplink power control informa(cid:173)
`tion. The DCI formats are divided into the following: DCI 30
`format 0, DCI format 1, DCI format IA, DCI format lB,
`DCI format IC, DCI format ID, DCI format 2, DCI format
`2A, DCI format 3 and DCI format 3A etc., herein the
`transmission mode 5 supporting the MU-MIMO utilizes
`downlink control information of the DCI format ID, and a 35
`downlink power offset field opower-offeet in the DCI format ID
`is used to indicate information of reducing power of a user
`by a half (i.e., -10 log 10(2)) in the MU-MIMO mode, since
`the MU-MIMO transmission mode 5 only supports MU(cid:173)
`MIMO transmissions of two users. Through the downlink 40
`power offset field, the MU-MIMO transmission mode 5 can
`support dynamic switching between a SU-MIMO Mode and
`a MU-MIMO mode, but no matter whether in the SU-MIMO
`mode or the MU-MIMO mode, the DCI format only sup(cid:173)
`ports one stream transmission for one UE. Although the 45
`Release 8 of the LTE supports single-user transmission of at
`most two streams in the transmission mode 4, since switch(cid:173)
`ing between the transmission modes can only be semi-static,
`in the Release 8 of the LTE, dynamic switching between
`single-user multi-stream transmission and multi-user trans- 50
`mission cannot be achieved.
`In the Release 9 of the LTE, in order to enhance downlink
`multi-antenna transmission, a transmission mode of dual(cid:173)
`stream beamforming is introduced, which is defined as
`transmission mode 8, and DCI format 2B is added in the 55
`downlink control information to support such transmission
`mode. There is an identification bit of a Scrambling Identity
`(SCID for short) in the DCI format 2B to support two
`different scrambling sequences. The eNB can allocate the
`two scrambling sequences to different users, and multiplex- 60
`ing is performed for multiple users in the same resource. In
`addition, when only one transport block is enabled, a New
`Data Indication (NDI) bit corresponding to a disabled trans(cid:173)
`port block is also used to indicate an antenna port during
`single-layer transmission.
`As the mainstream standard of the fourth generation
`mobile communication, the Long Term Evolution Advanced
`
`13
`
`

`

`US 10,498,515 B2
`
`7
`mainly transmit small-packet data, require a low data rate,
`and can tolerate a large data transmission delay. Since such
`terminals require a low data rate, for a Physical Dow