WO2011131067A1

WO2011131067A1 - Method and apparatus for processing hybrid automatic repeat request retransmission in spatial multiplexing mode

Info

Publication number: WO2011131067A1
Application number: PCT/CN2011/071931
Authority: WO
Inventors: 谭源春; 李宪玺
Original assignee: 中兴通讯股份有限公司
Priority date: 2010-04-21
Filing date: 2011-03-17
Publication date: 2011-10-27
Also published as: CN102237987B; CN102237987A

Abstract

The present invention discloses a method and an apparatus for processing Hybrid Automatic Repeat Request (HARQ) retransmission in spatial multiplexing mode, which are applied for solving the problems of large retransmission delays of Transmission Blocks (TBs) and the Multi-Input Multi-Output (MIMO) channel capacity being not fully utilized. The basic idea of the technical solution is: according to the number of layers and the Modulation Coding Scheme (MCS) parameter which are used in the first TB transmission of the HARQ transmission of a User Equipment (UE), the retransmission count of each TB, Rank Indicator (RI) and Channel Quality Indicator (CQI) information reported lately from the UE and the layer which is used in current Transmission Time Interval (TTI) of the UE and obtained by rank self-adaptation processing, a base station determines HARQ TBs to be retransmitted in current TTI of the UE and the MCS used by each TB. The present invention performs, on the basis of an RI and a CQI reported from a UE, the HARQ retransmission processing in spatial multiplexing mode, reduces the retransmission delays of the TBs, and improves the utility of the MIMO channel capacity at the same time.

Description

HARQ retransmission processing method and device in spatial multiplexing mode

The present invention relates to the field of communications, and in particular, to a HARQ retransmission processing method and apparatus in a spatial multiplexing mode. Background technique

Mimo (Multi-Input Multi-Output) is a wireless transmission technology that uses multiple ( Ν _τ ) transmit antennas and multiple ( W« ) receive antennas to effectively increase the capacity and link of wireless networks. Transmission performance, etc. The MIMO channel (represented by a matrix) formed by the N _r transmit and receive antennas can be decomposed into N _s independent channels. In the LTE (Long Term Evolution) system, the UE (User Equipment) is called It is Rank, which is called Layer on the network side, and ^≤ rmn{ N _T , N _R }.

There are two main ways to implement MIMO technology: space diversity and spatial multiplexing. In the LTE system, for the spatial multiplexing mode, the UE needs to feed back the metric of the MIMO channel to the network side, and the network side performs the Rank adaptive transmission according to the Rank reported by the UE. Spatial multiplexing includes two transmission modes: large delay CDD (Cyclic Delay Diversity) transmission mode and closed-loop spatial multiplexing mode.

In the LTE system, Hybrid Automatic Repeat Request (HARQ) technology can simultaneously transmit multi-packet data when transmitting data in a MIMO channel, and each packet data uses a separate layer. For downlink HARQ, the transmission is performed in an asynchronous adaptive manner. HARQ transmission is performed separately for each data stream. The data transmitted at the same time can be a new transmission, a retransmission, or both.

The prior art adaptively adjusts the rank from the state of rank change, and does not consider the factors of HARQ retransmission. When HARQ performs data transmission, it needs to retransmit TB (Transport Block, The transport block) block is indeterminate, and the TB block is subject to rank restrictions when transmitting. For example, when the rank adaptive adjustment of the current TTI (Transmission Time Interval) is 1 for transmission, the current HARQ needs to retransmit 2 buffers.

The patent "Space Multiplexing Mode Hybrid Automatic Repeat Request Processing Method and Apparatus" (application number is CN200910171244.5) proposes a HARQ processing technique based on the retransmission times and rank adaptive spatial multiplexing mode, and the above situation is processed as follows : When the rank adaptively adjusts the current ΤΤΙ layer number to 1 for transmission, and the current H HARQ needs to retransmit 2 TB blocks, retransmit 1 TB block. This processing may result in the following two problems: Problem 1: When the retransmitted TB block requires a SINR (Signal to Interference plus Noise Ratio) that is less than the current SINR, it is likely that the TB Block retransmission is still unsuccessful; Problem 2: The delay of the TB block that is not retransmitted increases, and the capacity of the MIMO channel may not be fully utilized. Summary of the invention

The technical problem to be solved by the present invention is to provide a processing method and apparatus for HARQ retransmission in a spatial multiplexing mode, which is used to solve the problem that the TB block retransmission delay is large and the MIMO channel capacity cannot be fully utilized.

In order to solve the above technical problem, the present invention provides a HARQ retransmission processing method in a spatial multiplexing mode, where the method includes:

The base station stores the number of layers and modulation and coding scheme (MCS) parameters used by the new transmission of the transport block (TB) of the hybrid adaptive retransmission (HARQ) transmission of the user equipment (UE), the number of retransmissions of each TB block, and receives And storing the rank indication and channel quality indication information that the UE reported last time; the base station performs rank adaptation processing to obtain a layer used by the current transmission time interval (ΤΉ) of the UE; and the base station according to the new transmission of the TB block of the HARQ transmission of the UE Determining the UE by using the number of layers and the MCS parameters, the number of retransmissions of each TB block, the rank indication and channel quality indication information that the UE last reported, and the layer currently used by the UE obtained by the rank adaptation process. Currently, the TB block to be retransmitted HARQ and the MCS used by each TB block are urgently needed. In order to solve the above technical problem, the present invention further provides a HARQ retransmission processing apparatus in a spatial multiplexing mode, the apparatus comprising:

An information collecting and storing module, configured to store a layer number and an MCS parameter used by a new transmission of a TB block of a HARQ transmission of the UE, and a number of times of retransmission of each TB block; receive and store a rank indication and channel quality that the UE last reported Instructing information; transmitting the stored information to a HARQ retransmission processing module;

a rank adaptive processing module, configured to perform rank adaptive processing, obtain a layer used by a current transmission time interval (TTI) of the UE, and send the layer to the HARQ retransmission processing module;

a HARQ retransmission processing module, configured to receive a layer number and an MCS parameter used by a new transmission of a TB of a HARQ transmission of a UE that is sent by the information collection and storage module, a number of times of retransmission of each TB block, and a rank that the UE last reported The indication and the channel quality indication information are received by the UE sent by the rank adaptation processing module at the layer used by the current TTI, and the TB block of the current TTI to be retransmitted by the UE and the MCS used by each TB block are determined.

The present invention performs the HARQ retransmission processing in the spatial multiplexing mode by using the RI (Lead Indicator) and the CQI (Channel Quality Indicator) reported by the UE, thereby reducing the retransmission delay of the TB block and improving the TB block. Utilization of MIMO channel capacity. DRAWINGS

1 is a flow chart of a HARQ retransmission processing method in the spatial multiplexing mode of the present invention.

2 is a block diagram showing the structure of a HARQ retransmission processing apparatus in the spatial multiplexing mode of the present invention. detailed description

The main idea of the present invention is to perform HARQ retransmission in spatial multiplexing mode by using RI ( Rank Indicator) and CQI (Channel Quality Indicator) reported by the UE to reduce retransmission of TB blocks. Delay, while increasing the utilization of MIMO channel capacity. The technical solutions of the present invention are further described below in conjunction with the accompanying drawings and specific embodiments. Referring to FIG. 1, the HARQ retransmission processing method in the spatial multiplexing mode of the present invention includes the following steps:

Step S1: The base station stores the number of layers used by the new transmission of the TB block of the HARQ transmission of the UE, and the MCS (Modulation and Coding Scheme), the number of times of retransmission of each TB block, and receives and stores the last report of the UE. Rank indication and channel quality indication information;

The latest report includes the current TTI, that is, the rank indication and channel quality indication information that was last reported by the UE in the current frame.

Step S2: The base station performs rank adaptive calculation on the current layer;

Step S3: The number of layers used by the base station according to the new transmission of the TB block of the HARQ transmission of the UE, the MCS, the number of retransmissions of each TB block, the rank indication and the channel quality indication information that the UE last reported, and the The rank adaptively calculates the layer currently used by the UE to determine the TB block that the UE currently needs to retransmit the HARQ, and the MCS used by each TB block. The flow of the HARQ retransmission processing method in the spatial multiplexing mode of the present invention shown in Fig. 1 will be further explained below. The HARQ retransmission processing method in the spatial multiplexing mode of the present invention includes the following steps: Step 1: The base station stores the number of layers and MCS used by each new TB block in the HARQ of the UE, the number of retransmissions of each TB block, and the receiving and storing The rank indication RI and channel quality indication CQI information reported by the UE last time.

Let the number of TB blocks that the UE waits for HARQ retransmission in the current TTI is TBNumwait, and each TB block is represented by TBwait(i), where e {0,...,73⁄4N罗 and t-1}; each TB block new The number of layers used for transmission is denoted by Ltb (i), and the total number of layers used for each TB block is Lneed = ^ ^Ltb ^ , where ie {0,..., TBNumwait-\}; MCS used by each TB block respectively Expressed by MCStb(i), where e {0,...,73⁄4N _M mw t_l}; the number of retransmissions of each TB block is represented by RetransNumtb(i), where e {0,...,73⁄4N _M mvra T_l}. The rank indication of the UE's recent recent 用 is indicated by Rlreport, each layer Represented by Lr(Z), where il,.."port). The number of codewords (or TBblocks) that can be transmitted on Rlreport is represented by Ncwreport, and the codeword is represented by CW(p), where {0, .. Ncwreport - 1} The CQI reported by the UE last time is represented by CQIreport(p), where pe {0, ..., Ncwreport - 1}. The last time "^ includes the current TTI.

For the LTE system, the corresponding codeword information can be known by the number of layers. For the ΜΙΜΟ channel of the receiving antenna of the 2 transmitting antenna 2, the mapping relationship between the number of layers and the codeword is as shown in Table 1, and the receiving antenna of the 4 transmitting antenna 4 is used. The mapping relationship between channel, layer number and codeword is shown in Table 2.

Step 2: The base station performs rank adaptive processing to obtain the layer currently used by the UE, and is represented by Ladaptive (including the number of layers and its position). Each layer is represented by L (m), where m e {0,..., Ladaptive - \}.

For the LTE system, the corresponding location information can be known by the number of layers. For the MIMO channel of the 2 transmit antenna 2 receive antenna, the positional mapping relationship between the number of layers and the layer is as shown in Table 1, for the MIMO of the receive antenna of the 4 transmit antenna 4 The mapping relationship between channel, layer number and layer position is shown in Table 2.

Step 3: Base

The rank adaptively calculates the layer currently used by the UE, and the rank indication and the channel quality indicator reported by the UE last time to determine the TB block of the current TTI to be retransmitted by the UE and the MCS used by each TB block. Do the following:

Step 3.1: Compare the total number of layers Lneed used by the new transmission of each TB block TBwait(i) of the UE to be HARQ retransmitted and the layer Ladaptive used by the rank adaptive calculation UE, and obtain the current TTI of the UE according to the comparison result. The MCS used by the TB block corresponding to the required layer Lneed includes:

When Lneed is equal to Ladaptive, proceed to step 3.2; when Lneed is less than Ladaptive, proceed to step 3.3; when Lneed is greater than Ladaptive, proceed to step 3.4;

Step 3.2: Obtain the TB block corresponding to the layer Lneed required by the current TTI of the UE. The MCS is represented by MCSneed(k), where ke {0, ..., TBNum _W ait- . The prior art solves this problem; proceeds to step 3.5;

Step 3.3: When Lneed is less than Ladaptive, calculate the MCS used by the TB block corresponding to the layer Lneed required by the current TTI of the UE according to the last reported rank indication Rlreport and the channel quality indicator CQIreport(p) and the weighting factor of the UE, using MCSa (k) indicates, where ke {0, ..., TBNumwait - l}. The force weight factor has a range of e (0,1), which is related to Lneed and Ladaptive. When the ratio of Ladaptive/Lneed is larger, β is larger.

Use the following steps:

The CQI and frequency efficiency mapping relationship shown by CQIreport(p) and Table 3 is used to obtain the frequency efficiency on each layer corresponding to the last reported Rlreport of the UE. The frequency efficiency on each layer is represented by SpecEjfrd). , Z e {1,..., A/report};

Obtain the spectral efficiency SpecEffneed(n) on each layer corresponding to the layer Lneed required by the UE, and use the formula (1.1) to calculate:

SpecEffneed(n) =

(0. l)

Lneed

Among them, {0,..., LM^ - 1}.

Calculate the MCS used by the TB block corresponding to the layer Lneed required by the current TTI of the UE, and use MCSneed(k), where k G {0, ..., TBNumwait- , use the following method:

Integrating the frequency efficiency SpecEffneed(n) on each layer corresponding to the layer Lneed required by the current TTI of the UE into the codeword; for the LTE system, determining the layer Lneed required by the current TTI of the UE and Table 1 or Table 2 a layer on the codeword, and the average value of the spectral efficiency corresponding to the layer included in the codeword is recorded as the spectral efficiency on the codeword;

Determine the MCSneed(k) of the currently used codeword according to the frequency efficiency and frequency efficiency of the codeword currently used by the UE and the mapping relationship between the frequency and the MCS;

The MCS used on each codeword is the one that each TB block can use in the current ΤΉ retransmission. MCS; Go to step 3.5.

Step 3.4: When Lneed is greater than Ladaptive, calculate the MCS used by the TB block corresponding to the layer Lneed required by the current TTI of the UE according to the last reported rank indication Rlreport and the channel quality indicator CQIreport(p) and the weighting factor y. MCSa(k) denotes, where k G {0, ..., TBNumwait - l}; The force weight factor y ranges from ye (0, 1 ], related to Lneed and Ladaptive, when Ladaptive/Lneed ratio The smaller, the smaller ^;

Use the following steps to calculate:

The CQI and frequency efficiency mapping relationship shown by CQIreport(p) and Table 3 is used to obtain the frequency efficiency on each layer corresponding to the last reported Rlreport of the UE. The frequency efficiency on each layer is represented by SpecEjfrd). , le Rlreport} ,

Obtain the spectral efficiency SpecEffneed(n) on each layer corresponding to the layer Lneed required by the UE's current Spec, using the formula (1.2):

7* ∑ SpecEjfriD

SpecEffneed(n) = ^ (0. 2)

Lneed

Where {0, ..., LM^ - 1} ,

The MCS used to obtain the TB block corresponding to the layer Lneed required by the current TTI of the UE is represented by MCSneed(k), where k G {0, ..., TBNumwait_ , uses the following method:

The frequency efficiency SpecEffneed(n) on each layer corresponding to the layer Lneed required by the current TTI of the UE is integrated into the codeword. For the LTE system, the layer Lneed required by the current TTI of the UE is determined with Table 1 or Table 2. The layer on the codeword, and the average value of the spectral efficiency corresponding to the layer included in the codeword is recorded as the spectral efficiency on the codeword.

The MCSneed(k) of the currently used codeword is determined according to the spectral efficiency of the codeword used by the current TTI of the UE and the mapping relationship between the spectral efficiency and the MCS shown in Table 4. The MCS used on each codeword is the TB block. MCS that can be used at the time of retransmission; go to step 3.5.

Step 3.5: According to the new transmission of each TB block TBwait(i) of the UE to be HARQ retransmitted The relationship between the used MCStb(i) and the MCSneed(k) used by the TB block corresponding to the layer Lneed required by the current TTI of the UE is as follows:

When the number of data blocks to be retransmitted is TBNumwait=l, it is judged whether MCStb(i) and MCSneed(k) satisfy the formula (1.3).

MCSneed(0) ≥ MCStb(0) (0. 3)

When the formula (1.3) is satisfied, the TB block is retransmitted, and the used MCS is MCStb(O), and the codeword used for the TB block transmission is codeword 0;

When the formula (1.3) is not satisfied, the TB block under the HARQ is not retransmitted.

When the number of data blocks to be retransmitted is TBNumwait=2, it is judged whether MCStb(i) and MCSneed(k) satisfy formula (1.4) or formula (1.5),

If the formula (1.4) is satisfied, the two TB blocks (TBwait(O) and TBwait(l)) are retransmitted, wherein the MCS used by TBwait(O) is MCStb(O), and the codeword used is code. Word 0; TBwait(l) The MCS used is MCStb(l), and the codeword used is codeword 1;

If the formula (1.5) is satisfied, the two TB blocks (TBwait(O) and TBwait(l)) are retransmitted, wherein the MCS used by TBwait(O) is MCStb(O), and the codeword used is code. Word 1; TBwait(l) The MCS used is MCStb(l), and the codeword used is codeword 0.

If they are not satisfied, further judge whether the formula (1.6) is satisfied:

MCSneedik) ≥ MCStbii) (0. 6)

Where i, k ^Q, .. " TBNumwait- r , JU≠;:.

When the formula (1.6) is satisfied, the Tbwait(k) is retransmitted, the MCS used is MCStb(k), and the codeword used is codeword 0; When the formula (1.6) is not satisfied, it is further judged whether the formula (1.7) is satisfied:

MCStb(i)≤ ^ MCSneed(k) (0. 7) where " is the weighting factor and takes the value (0, 1) (value greater than 0 and less than or equal to 1), ie {0, ... , TBNumwait - 1};

When both MCStb(O) and MCStb(l) satisfy the formula (1.7), the TB block with a large number of retransmissions in the two TB blocks is retransmitted, and the MCS used for retransmission is the number of retransmissions. The MCS used for the new TB block is the codeword 0. When the number of retransmissions is the same in the two TB blocks, the smaller MCSb(O) and MCStb(l) are taken. The corresponding TB block is retransmitted, and the MCS used for retransmission is the MCS newly used by the retransmitted TB block, and the used codeword is codeword 0; otherwise, one TB block is selected for retransmission, and The MCS used for the transmission is the MCS newly used for the retransmitted TB block, and the codeword used is codeword 0.

Table 1

Table 2

/3/: O S60nl£ z-90oiAV

24 4.5234

25 4.8193

26 5.1152

27 5.33495

28 5.5547 Referring to FIG. 2, which is a structural block diagram of a HARQ retransmission processing apparatus in a spatial multiplexing mode according to the present invention, the apparatus of the present invention includes: an information collecting and storing module 20, a rank adaptive processing module 21, and a HARQ retransmission processing. Module 22. among them,

The information collection and storage module 20 is configured to store the number of layers and MCS parameters used by the new transmission of the TB block of the HARQ transmission of the UE, and the number of times of retransmission of each TB block; and receive and store the RI and CQI information reported by the UE last time. Sending the stored information to the HARQ retransmission processing module;

The rank adaptive processing module 21 is configured to perform rank adaptation processing, obtain a layer used by a current transmission time interval (TTI) of the UE, and send the layer to the HARQ retransmission processing module;

The HARQ retransmission processing module 22 is configured to receive the number of layers and MCS parameters used by the new transmission of the TB of the HARQ transmission of the UE sent by the information collection and storage module 20, the number of times of retransmission of each TB block, and the last report of the UE. The RI and CQI information is received by the UE sent by the rank adaptive processing module 21 at the layer currently used by the UE, and the TB block of the current TTI to be retransmitted by the UE and the MCS used by each TB block are determined.

In a preferred embodiment of the present invention, the information collecting and storing module 20 receives the last time the UE includes the current TTI.

In a preferred embodiment of the present invention, the HARQ retransmission processing module 22 is further configured to compare the total number of layers used in the new transmission of the TB block of the HARQ transmission of the UE, Lneed, and the rank adaptive computing UE currently used. The layer is Ladaptive and processed according to the comparison results.

In a preferred embodiment of the present invention, the HARQ retransmission processing module 22 is further configured to: when Lneed is equal to Ladaptive, obtain the MCS used by the TB block corresponding to the layer Lneed required by the current TTI of the UE, and use MCSneed. (k) indicates, where k G {0, ..., TBNumwait - l}. In a preferred embodiment of the present invention, the HARQ retransmission processing module 22 is further configured to:

When Lneed is less than Ladaptive, the MCS used by the TB block corresponding to the layer Lneed required by the current UE is calculated according to the most recent uplink indication of the UE, the Rlreport and the channel quality indicator CQIreport(p), and the weighting factor, and the MCSa is used. k) denotes, where kG{0,...,TBNumwait-l}; the weighting factor has a value range of e (0,1), and the weighting factor is related to Lneed and Ladaptive, when the ratio of Ladaptive/Lneed is larger , the bigger the

From CQIreport(p) and CQI to the frequency efficiency mapping relationship, the spectral efficiency on each layer corresponding to the last Rlreport of the UE is obtained. The spectral efficiency on each layer is represented by SpecEffriT), where {l,. .., ?/re/wri};

Calculate the frequency efficiency SpecEffneed(n) on each layer corresponding to the layer Lneed required by the current UE, and let SpecEffneed(n) =

(0.8)

Lneed

Among them, we

1};

Obtaining the MCS used by the TB block corresponding to the layer Lneed required by the current TTI of the UE, represented by MCSneed(k), where ke {Q,...,TBNumwait-W ,

The frequency efficiency SpecEffneed(n) on each layer corresponding to the layer Lneed required by the current TTI of the UE is integrated into the codeword, and the average frequency efficiency corresponding to the layer included in the codeword is recorded as the codeword. Frequency efficiency

The MCSneed(k) of the currently used codeword is determined according to the frequency efficiency of the codeword used by the UE and the mapping relationship between the frequency efficiency and the MCS, and the MCS used on each codeword is the retransmission of each TB block in the current frame. The MCS that can be used.

In a preferred embodiment of the present invention, the HARQ retransmission processing module 22 is further configured to: When Lneed is greater than Ladaptive, then:

The MCS used for calculating the TB block corresponding to the layer Lneed required by the current TTI of the UE according to the rank indication Rlreport of the UE and the channel quality indicator CQIreport(p) and the weighting factor ^ is represented by MCSa(k), where , {0, ..., TBNumwait - l , the weighting factor y has a value range of ye (0, 1), which is related to Lneed and Ladaptive. When the ratio of Ladaptive/Lneed is smaller, ^ is smaller.

From CQIreport(p) and CQI to the frequency efficiency mapping relationship, the spectral efficiency on each layer corresponding to the last Rlreport of the UE is obtained. The spectral efficiency on each layer is represented by SpecEffriT), where {l, . .., ?/re/wri};

Obtain the spectral efficiency SpecEffneed(n) on each layer corresponding to the layer Lneed required by the UE.

7* ∑ SpecEffriT)

Let SpecEffneed(n) = ^ (0.9)

Lneed

Where, w e {0, ..., Lwei^— 1} ;

Obtaining the MCS used by the TB block corresponding to the layer Lneed required by the current TTI of the UE, represented by MCSneed(k), where k e {Q, ..., TBNumwait_W ,

The frequency efficiency SpecEffneed(n) on each layer corresponding to the layer Lneed required by the current TTI of the UE is integrated into the codeword, and the average value of the spectral efficiency corresponding to the layer included in the codeword is recorded as the codeword. Frequency efficiency

The MCS used on each codeword is the MCS that each TB block can use during the current ΤΉ retransmission.

In a preferred embodiment of the present invention, the HARQ retransmission processing module 22 is further configured to: The relationship between the MCStb(i) used by each new TB block under the HARQ of the UE and the MCSneed(k) used by the TB block corresponding to the layer Lneed required by the current TTI of the UE is processed as follows:

When the number of data blocks to be retransmitted is TBNumwait=l, it is judged whether MCStb(i) and MCSneed(k) are satisfied:

MCSneed(0) ≥ MCStb(0) (0.10)

If yes, the TB block is retransmitted, and the used MCS is MCStb(O), and the codeword used for the TB block transmission is codeword 0;

If not, then the HARQ will not be retransmitted.

In a preferred embodiment of the present invention, the HARQ retransmission processing module 22 is further configured to:

When the number of data blocks to be retransmitted is TBNumwait=2, it is judged whether MCStb(i) and MCSneed(k) are satisfied:

Or is it satisfied:

If the formula (1.4) is satisfied, the two data blocks to be retransmitted, TBwait(O) and TBwait(l), are retransmitted, wherein the MCS used by TBwait(O) is MCStb(O), and the codeword used is code. Word 0; TBwait(l) The MCS used is MCStb(l), and the codeword used is codeword 1;

If the formula (1.5) is satisfied, the two data blocks to be retransmitted, TBwait(O) and TBwait(l), are retransmitted, wherein the MCS used by TBwait(O) is MCStb(O), and the codeword used is code. Word 1; TBwait(l) The MCS used is MCStb(l), and the codeword used is codeword 0;

If neither formulas (1.4) and (1.5) are satisfied, then further judge whether it is satisfied: MCSneed(k) ≥ MCStb(i) (0.13) where i, k TBNumwait— V , JU≠fc.

If the formula (1.6) is satisfied, then Tbwait(i) is retransmitted, the MCS used is MCStb(i), and the codeword used is codeword 0;

If the formula (1.6) is not satisfied, it is further judged whether it is satisfied:

MCStb(i) ≤ ^ MCSneed(k) (0.14) where " is a weighting factor and takes a value of (0, 1) (a value greater than 0 and less than or equal to 1), i, k € { 0, ... , TBNumwait - 1};

If both MCStb(O) and MCStb(l) satisfy the formula (1.7), the TB block with the highest number of retransmissions in the two TB blocks is retransmitted, and the MCS used for retransmission is the retransmission. For the MCS that is newly transmitted by the TB block with a large number of times, the codeword used is codeword 0; if the number of retransmissions in the two TB blocks is the same, the smaller MCS of MCStb(O) and MCStb(l) is taken. The corresponding TB block is retransmitted, and the MCS used for retransmission is the MCS newly used by the retransmitted TB block, and the used codeword is codeword 0; otherwise, one TB block is selected for retransmission, and The MCS used for retransmission is the MCS newly used for the retransmitted TB block, and the codeword used is codeword 0. The technical solutions of the present invention are exemplarily described below through examples in specific applications.

Application example 1 :

In the MIMO channel of the 2 transmit antenna and the 2 receive antenna, the closed loop MIMO transmission mode is adopted for the UE.

Step 1: The base station stores the current HARQ information that the UE needs to retransmit as follows: The number of TB blocks to be retransmitted is 2, which is represented by TBNumwait; each TB block is represented as TBwait(O) and TBwait(l) respectively; The number of layers used is 1 and 1, respectively, represented by Ltb (0) and Ltb (1), and the total number of layers used for each TB block is 2; the MCS used for each TB block is 11 and 9, respectively, using MCStb ( O) and MCStb(l) indicate; the number of retransmissions of each TB block is 1 and 1 respectively. RetransNumtb(O) and RetransNumtb(l) are used respectively. The base station receives and stores the most recently reported rank indication RI and channel quality indicator CQI information of the UE: the last reported rank indication of the UE is 2, denoted by Rlreport; each layer is represented by Lr(0) and Lr(l) in sequence; It can be seen that the number of codewords (or TB blocks) that can be transmitted on Rlreport is 2, which is represented by Ncwreport, and each codeword is represented by CW(0) and CW(1) in sequence; the recently reported CQI of the UE is 8 and 5, which are sequentially used. CQIreport(O) and CQIreport(l) are indicated.

Step 2: The base station performs rank adaptive processing to obtain the layer used by the current TTI of the UE, and is represented by Ladaptive (including the number of layers and its location). Let Ladaptive be 2, and each layer in Ladaptive is represented by Liz(0) and Liz(l) in turn. The rank adaptively calculates the layer currently used by the UE, and the rank indication and the channel quality indicator reported by the UE last time to determine the number of TBs of the current TTI to be retransmitted by the UE and the MCS used by each TB block. Do the following:

Step 3.1: Compare the total number of layers used by the new transmission of the TB block of the HARQ transmission of the UE Lneed and the rank adaptive calculation of the layer Ladaptive currently used by the UE. Lneed is equal to Ladaptive, proceed to step 3.2;

Step 3.2: Calculate the MCS used by the TB block corresponding to the layer Lneed required by the current TTI of the UE, and use MCSneed(O) and MCSneed(l) in turn. Let MCSneed(O) be 12 and MCSneed(l) be 10, proceed to step 3.5;

Step 3.5: According to the MCStb(i) used by each new TB block under the HARQ of the UE

The relationship between the MCSneed(k) used by the TB block corresponding to the layer Lneed required by the current TTI of the UE is processed as follows:

Judge TBNumwait=2,

Further judge that MCStb(i) and MCSneed(k) satisfy the formula (1.4),

If the formula (1.4) is satisfied, the two TB blocks (TBwait(O) and TBwait(l)) are retransmitted. Among them, the MCS used by TBwait(O) is MCStb(O), the codeword used is codeword 0; the MCS used by TBwait(l) is MCStb(l), and the codeword used is codeword 1. The process ends. Application example 2:

Under the MIMO channel of 4 transmit antennas and 4 receive antennas, a large delay CDD transmission mode is applied to the UE. Let "0.7.

Step 1: The base station stores the current HARQ information that the UE needs to retransmit as follows: The number of TB blocks to be retransmitted is 2, which is represented by TBNumwait; each TB block is represented as TBwait(O) and TBwait(l) respectively; The number of layers used is 1 and 2, respectively, where TBwait(O) uses Ltb (0), TBwait(l) uses Ltb (1) and Ltb (2), and the total TB block is used. The number is 3, denoted by Lneed; the MCS used by each TB block is 19 and 18, respectively, represented by MCStb(O) and MCStb(l); the number of retransmissions of each TB block is 1 and 2 times respectively, respectively, using RetransNumtb (O) and RetransNumtb (l) are indicated. The base station receives and stores the rank indication RI and the channel quality indicator CQI information recently reported by the UE as follows: the most recently reported rank indication of the UE is 4, which is represented by Rlreport; each layer sequentially uses Lr(0), Lr(l), Lr(2) And Lr (3) said; from Table 2, the number of codewords (or TB blocks) that can be transmitted on Rlreport is 2, represented by Ncwreport, each codeword is represented by CW (0) and CW (1) in turn; The reported CQI is 10, expressed by CQIreport(O);

Step 2: The base station performs rank adaptive processing to obtain a layer used by the current TTI of the UE, and is represented by Ladaptive (including the number of layers and its location). Let Ladaptive be 4, each layer in Ladaptive is sequentially represented by Liz(0) and Liz(l); the rank adaptively calculates the layer currently used by the UE, and the rank indication and channel quality indicator reported by the UE last time to determine the current UE. The number of TBs of the TTI to be retransmitted HARQ and the MCS used by each TB block are processed as follows: Step 3.1: Compare the total number of layers Lneed used by the new transmission of the TB block of the HARQ transmission of the UE and the rank adaptively calculate the layer Ladaptive currently used by the UE. It can be seen from step 1 that Lneed is 3, and it can be known from step 2 that Ladaptive is 4, and it is judged that Lneed is smaller than Ladaptive, and proceeds to step 3.3;

Step 3.3: According to the rank indication recently reported by the UE, the Rlreport and the channel quality indicator

CQIreport(p) and the weighting factor calculate the MCS used by the TB block corresponding to the layer Lneed required by the current TTI of the UE, and are represented by MCSa(k), where k^0, ..., TBNum _W ait_Y , Let the weighting factor be 0.7,

Use the following steps to calculate:

The mapping between CQIreport(p) and CQI and frequency efficiency shows that the UE has been in the last time.

The spectral efficiency on each layer corresponding to Rlreport. The spectral efficiencies on each layer are: SpecEffr(0) = 2.7305, SpecEffr(l) = 2.7305, SpecEffr(2) = 2.7305, SpecEffr(3) = 2.7305; Calculate each of the layers Lneed required by the UE's current ΤΉ The frequency efficiency of the layer, SpecEffneed(n), is calculated by the formula (1.1), and the SpecEffneed(O) is 2.548, the SpecEffneed(l) is 2.548, and the SpecEffneed(2) is 2.548.

Further calculating the MCS used by the TB block corresponding to the layer Lneed required by the UE, and using MCSneed(k), where ke { ), ···, TBN draw ait_, use the following method: The frequency efficiency SpecEffneed(n) on each layer corresponding to the layer Lneed required by the current TTI is integrated into the codeword. The average value of the spectral efficiency corresponding to the layer included in the codeword is recorded as the frequency efficiency on the codeword. The layer corresponding to the codeword CW(0) is Ltb (0), the frequency efficiency on the codeword is SpecEffneed(O) (ie, 2.548); the layer corresponding to the codeword CW(1) is Ltb (l) and Ltb(2), the frequency efficiency on the codeword is the average of SpecEffneed(l) and SpecEffneed(2) (ie 2.548);

The MCSneed(k) of the currently used codeword is determined according to the frequency efficiency of the codeword currently used by the UE and the mapping relationship between the frequency efficiency and the MCS. Wherein, the MCS used by the codeword CW(0) is 16, the code word CW (1) uses an MCS of 16;

The MCS used on each codeword is the MCS that each TB block can use during the current ΤΉ retransmission, and proceeds to step 3.5;

Step 3.5: According to the relationship between the MCStb(i) used by each new TB block in the HARQ of the UE and the MCSneed(k) used by the TB block corresponding to the layer Lneed required by the current TTI of the UE, the following processing is performed:

Judge TBNumwait=2,

Further judge that MCStb(i) and MCSneed(k) do not satisfy formula (1.4) and formula (1.5), and further judge that formula (1.6) is not satisfied.

Further judge that both MCStb(O) and MCStb(l) satisfy the formula (1.7),

Further, it is determined that the number of retransmissions of TBwait(l) is greater than the number of retransmissions of TBwait(O), so TBwait(l) is used for retransmission, and the MCS used for retransmission is the MCS used by TBwait(l) new transmission, that is,

18. The codeword used is codeword 0. The process ends.

It should be noted that the above description is only a preferred embodiment of the present invention, and is not intended to limit the technical solution of the present invention. Any equivalent replacement or corresponding improvement made by those skilled in the art to the technical features of the present invention is still in the present invention. Within the scope of the protection, the patent protection scope of the invention shall be determined by the appended claims.

Claims

Claim

A HARQ retransmission processing method in a spatial multiplexing mode, the method comprising:

The base station stores the number of layers and modulation and coding scheme (MCS) parameters used by the new transmission of the transport block (TB) of the hybrid adaptive retransmission (HARQ) transmission of the user equipment (UE), the number of retransmissions of each TB block, and receives And storing the rank indication and channel quality indication information that the UE reported last time; the base station performs rank adaptation processing to obtain a layer used by the current transmission time interval (ΤΉ) of the UE; and the base station according to the new transmission of the TB block of the HARQ transmission of the UE The number of layers used and the MCS parameters, the number of retransmissions of each TB block, the rank indication and channel quality indication information that the UE last reported, and the layer currently used by the UE obtained by the rank adaptation process to determine the current UE status. The TB block to be retransmitted HARQ and the MCS used by each TB block.

The method according to claim 1, wherein the base station uses the number of layers and MCS parameters used for new transmission of the TB block of the HARQ transmission of the UE, the number of retransmissions of each TB block, and the latest of the UE. The rank indication and the channel quality indication information that are reported at one time, and the layer used by the current TTI of the UE obtained by the rank adaptation process to determine the TB block of the current TTI to be retransmitted by the UE and the MCS used by each TB block, including:

The total number of layers used for the new transmission of the TB block of the HARQ transmission of the UE is compared with the Lneed and rank adaptive calculations. The layer Ladaptive currently used by the UE is processed according to the comparison result.

3. The method according to claim 2, wherein the processing according to the comparison result comprises:

When Lneed is less than Ladaptive, the MCS used by the TB block corresponding to the layer Lneed required by the current TTI of the UE is calculated according to the last uplink indication of the UE, the Rlreport and the channel quality indicator CQIreport(p), and the weighting factor. (k) represents, where k G {0, ..., TBNumwait - l} , TBNumwait is the number of TB blocks that the UE is to be retransmitted by the HARQ in the current TTI; the weighting factor has a value range of (0, 1), Includes the following steps:

Obtain the spectral efficiency SpecEffneed(n) on each layer corresponding to the layer Lneed required by the UE, and let SpecEffneed(n) =

(0.15)

Lneed

Where, w e {0, ..., Lwei^— 1} ;

The method according to claim 2, wherein the processing according to the comparison result further comprises:

When Lneed is greater than Ladaptive, then:

The MCS used by the TB block corresponding to the layer Lneed required for calculating the current TTI of the UE according to the most recent uplink indication of the UE, the Rlreport and the channel quality indicator CQIreport(p), and the weighting factor ^, is represented by MCSneed(k), Where ke { ), ···, TBNumwait— , y (0,1];

Includes the following steps:

The relationship between CQIreport(p) and CQI and frequency efficiency is derived from the last time the UE was up. The spectral efficiency on each layer corresponding to Rlreport, the spectral efficiency on each layer is represented by SpecEffrQ, where {l, ..., ?/re/wri};

Rlreport-1

∑ SpecEffr )

Let SpecEffneed(n) = (0.16)

Lneed

Where, w e {0, ..., Lwei^— 1} ;

The frequency efficiency SpecEffneed(n) on each layer corresponding to the layer Lneed required by the current TTI of the UE is integrated into the codeword, and the average value of the frequency efficiency corresponding to the layer included in the codeword is recorded as the code. Frequency efficiency in words;

The method according to any one of claims 3 or 4, wherein the method further comprises:

The relationship between the MCStb(i) used by each new TB block in the HARQ of the UE and the MCSneed(k) used by the TB block corresponding to the layer Lneed required by the current TTI of the UE is as follows:

MCSneed(0)≥ MCStb(0) (0.17)

If yes, the TB block is retransmitted, and the used MCS is MCStb(O); If not, the TTI does not retransmit the TB block under the HARQ.

The method according to claim 5, wherein the method further comprises: determining whether MCStb(i) and MCSneed(k) are satisfied when the number of data blocks to be retransmitted is TBNumwait=2:

MCSneed(0)≥MCStb(0)

□ (0.18)

MCSneed{\)≥MCStb{\) or is it satisfied:

MCSneed(0)≥MCStb(l)

□ (0.19)

MCSneed(l)≥MCStb(0) If the formula (1.4) is satisfied, the two data blocks to be retransmitted TBwait(O) and TBwait(l) are retransmitted, and the MCSs used are MCStb(O) and MCStb respectively. (l);

If formula (1.5) is satisfied, TBwait(O) and TBwait(l) are retransmitted, and the MCSs used are MCStb(l) and MCStb(O), respectively;

If they are not satisfied, further judge whether it is satisfied:

MCSneed(k)≥MCStb(i) (0.20)

Where i, k ^Q, .." TBNumwait_ r , JU≠fc. If formula (1.6) is satisfied, Tbwait(j) is retransmitted, and the used MCS is MCStb(i); if the formula is not satisfied ( 1.6), then further determine whether it is satisfied:

MCStb(i) ≤ ^ MCSneed(k) (0.21) where " is a weighting factor and takes a value of (0, 1) (a value greater than 0 and less than or equal to 1), i, k € { 0, ... , TBNumwait - 1};

If both MCStb(O) and MCStb(l) satisfy the formula (1.7), the TB block with the highest number of retransmissions in the two TB blocks is retransmitted, and the MCS used for retransmission is the retransmission. The MCS used by the newly transmitted TB block; if the number of retransmissions in the 2 TB blocks is the same, the MCStb(O) is taken. Retransmitting the TB block corresponding to the smaller MCS in the MCStb(l), and retransmitting the used MCS to the newly transmitted MCS of the retransmitted TB block; otherwise, selecting one TB block for retransmission, and The MCS used for retransmission is the MCS newly used for the retransmitted TB block.

A HARQ retransmission processing apparatus in a spatial multiplexing mode, wherein the apparatus comprises:

a rank adaptive processing module, configured to perform rank adaptive processing, obtain a layer currently used by the UE, and send the layer to the HARQ retransmission processing module;

The apparatus according to claim 7, wherein the HARQ retransmission processing module is further configured to compare a total layer number Lneed and a rank adaptive computing UE used for new transmission of a TB block of a HARQ transmission of the UE. The layer currently used by Ladaptive is processed according to the comparison result.

The device according to claim 8, wherein the HARQ retransmission processing module is further configured to:

When Lneed is less than Ladaptive, the MCS used by the TB block corresponding to the layer Lneed required by the current TTI of the UE is calculated according to the last uplink indication of the UE, the Rlreport and the channel quality indicator CQIreport(p), and the weighting factor. (k) indicates that, among them, k€{0,... BNumwait -1}; The range of the force weight factor is e (0, 1 ], and the mapping between CQIreport(p) and CQI and frequency efficiency shows that the UE has been on the last time. of

The spectral efficiency on each layer corresponding to Rlreport, the frequency efficiency on each layer is represented by SpecEfj j, where {l,..., ?/re/wri}; corresponding to the layer Lneed required by the UE Spectral efficiency on each layer

SpecEffneed(k) , β* ∑ SpecEjr(j)

Let SpecEffneed(k) = ^J — (0.22)

Lneed

Where te{0,...,Lw^_l};

The MCS used to obtain the TB block corresponding to the layer Lneed required by the current TTI of the UE is represented by MCSneed(k), where {0,...,TBNumwait-l

The frequency efficiency SpecEffneed(k) on each layer corresponding to the layer Lneed required by the current TTI of the UE is integrated into the codeword, and the average spectral efficiency corresponding to the layer included in the codeword is recorded as the codeword. Frequency efficiency

When Lneed is greater than Ladaptive, then:

The MCS used by the TB block corresponding to the layer Lneed required for calculating the current TTI of the UE according to the most recent uplink indication of the UE, the Rlreport and the channel quality indicator CQIreport(p), and the weighting factor ^, is represented by MCSneed(k), Where ke {), ···, TBNumwait— , y (0,1];

The spectral efficiency on each layer corresponding to the last Rlreport of the UE is obtained by CQIreport(p) and CQI and frequency efficiency mapping. The spectral efficiency on each layer is expressed by SpecEfj V). Among them, le {l, ..., RIreport);

(0.23)

Lneed

Where n e {0, ..., Lwei3⁄4? - 1} ;

The MCS used to obtain the TB block corresponding to the layer Lneed required by the current TTI of the UE is represented by MCSneed(k), where {0, ..., TBNumwait-l

The device according to any one of claims 9 or 10, wherein the HARQ retransmission processing module is further configured to:

MCSneed(0) ≥ MCStb(0) (0.24)

If it is satisfied, the TB block is retransmitted, and the adopted MCS is MCStb(O);

If not, the TTI does not retransmit the TB block under the HARQ.

The device according to claim 11, wherein the HARQ retransmission processing module is further configured to:

MCSneed(0)≥MCStb(0)

□ (0.25)

MCSneed{\)≥MCStb{\) or is it satisfied:

MCSneed(0)≥MCStb(l)

□ (0.26)

MCSneed(Y)≥MCStb(0) If the formula (1.4) is satisfied, the two data blocks to be retransmitted TBwait(O) and TBwait(l) are retransmitted, and the MCSs used are MCStb(O) and MCStb respectively. (l);

If they are not satisfied, further judge whether it is satisfied:

MCSneed(k)≥MCStb(i) (0.27)

Where i, k ^Q, .." TBNumwait_ r , JU≠fc. If formula (1.6) is satisfied, Tbwait(i) is retransmitted, and the used MCS is MCStb(i); if the formula is not satisfied ( 1.6), then further determine whether it is satisfied:

MCStb(i) ≤ ^ MCSneed(k) (0.28) where " is a weighting factor and takes a value of (0, 1) (a value greater than 0 and less than or equal to 1), i, k € { 0, ... , TBNumwait - 1};