WO2011143970A1 - Multi-input multi-output channel self-adaptation method and device - Google Patents

Abstract

A Multi-Input Multi-Output (MIMO) channel self-adaptation method and device are provided by the present invention, which determines, according to the layer number Layer1 of channels indicated in a Rank Indication (RI) reported by a user equipment and channel quality indication information CQIreport reported by the user equipment, Modulation and Coding Schemes (MCSs) of self-adapted code words. With the present invention, MCSs of code words can be determined correctly when the layer number of MIMO channels is changed, thus the MIMO channel capacity is fully utilized.

Description

 Method and device for multi-input and multi-output channel adaptation

 The present invention relates to the field of communications technologies, and in particular, to a method and apparatus for multi-input and multi-output channel adaptation. Background technique

 In wireless communication systems, in order to increase the data transmission rate and system throughput, multi-input and multi-output (MIMO) technology can be used to achieve the highest data transmission through an acquireable system. The way the throughput of the system is transmitted via the MIMO channel, one or more data streams are transmitted to achieve good system performance.

 There are two main ways to implement MIMO technology: space diversity and spatial multiplexing. In the long-term implementation (LTE) system, for the spatial multiplexing mode, the user equipment (UE, User Equipment) needs to feed back the rank of the MIMO channel matrix to the network side, and the network side performs the adaptive transmission of the rank 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 MIMO transmission mode.

 In the prior art, the number of channel layers is adaptively adjusted from the change of the rank, but the problem of the modulation and coding scheme (MCS, Modulation and Coding Scheme) used in the adaptive adjustment of the channel layer number is not solved. The MCS determination on the word is not accurate enough, which may result in the problem of not being able to utilize the MIMO channel capacity sufficiently efficiently. Summary of the invention

It is an object of the present invention to provide a method and apparatus for multi-input and multi-output channel adaptation. When the number of layers of a MIMO channel changes, the MCS on the codeword can be accurately determined, thereby fully utilizing the MIMO channel capacity. According to an aspect of the present invention, a method for multi-input multiple-output channel adaptation is provided, the method comprising the steps of:

 The base station receives and stores the first layer number of the channel indicated by the rank indication RI recently reported by the user equipment, and the channel quality indication information CQIreport;

 The base station adaptively processes Layerl to obtain the second layer Layer2 used by the user equipment at the current transmission time interval TTI;

 The base station compares the size of the Layer 2 and the Layer1, and calculates a spectral efficiency of the layers of the Layer 2 according to the comparison result and the CQIreport; according to the preset number of layers and the spectral efficiency SpecEffa of each layer on the codeword, The average value of the spectral efficiency SpecEffa of all layers on the same codeword is taken as the frequency efficiency on the codeword; the MCS on the codeword is determined according to the frequency efficiency on the codeword and the mapping relationship between the spectral efficiency and the MCS.

 According to another aspect of the present invention, an apparatus for multi-input multiple-output channel adaptation is provided, the apparatus comprising:

 a layer number and channel quality indicator information storage module, configured to receive and store Layerl and channel quality indication information CQIreport of the channel indicated by the rank indication RI recently reported by the user equipment, and send the layer;

 The layer number adaptive processing module is configured to perform adaptive processing on the Layerl to obtain the Layer 2 used by the current TTI of the user equipment;

 An MCS determining module, configured to compare sizes of the Layer 2 and the Layer 1, and calculate a spectral efficiency SpecEffa of each layer of the Layer 2 according to the comparison result and the CQIreport, and then according to a preset correspondence between a number of layers and a codeword Determining the codeword corresponding to the Layer 2 and the frequency efficiency on the codeword, and determining the MCS on the codeword according to the frequency efficiency on the codeword and the mapping relationship between the frequency efficiency and the MCS.

Compared with the prior art, the present invention has the following advantages: In the present invention, Layer 1 and channel quality indication information CQIreport of a channel indicated by a rank indication RI reported by a user equipment The MCS on the adaptive codeword is determined such that when the number of layers of the MIMO channel changes, the MCS on the codeword is accurately determined, thereby making full use of the MIMO channel capacity. DRAWINGS

 FIG. 1 is a flow chart of a multiple input multiple output channel adaptive method according to an embodiment of the present invention; FIG.

 2 is a specific processing flowchart of a multiple input multiple output channel adaptive method according to an embodiment of the present invention;

 FIG. 3 is a diagram of a first embodiment of a multiple input multiple output channel adaptation method according to an embodiment of the present invention; FIG.

 4 is a diagram of a second embodiment of a multiple input multiple output channel adaptation method according to an embodiment of the present invention;

 FIG. 5 is a block diagram of a multiple input multiple output channel adaptive apparatus according to an embodiment of the present invention; FIG. 6 is a schematic structural diagram of the MCS determining module shown in FIG. detailed description

 The preferred embodiments of the present invention are described in detail below with reference to the accompanying drawings.

 FIG. 1 is a flowchart of a multiple input multiple output channel adaptation method according to an embodiment of the present invention. As shown in FIG. 1 , the method includes the following steps:

 In step 101, the base station receives and stores the layer number (LayerNum) of the channel indicated by the rank indication (Rlreport) recently reported by the user equipment, and the channel quality indication information CQIreport.

In this step, LayerNum (herein referred to as Layer 1) is the number of layers of the channel indicated by the rank indication (RI), and each layer is represented by Lr(i), where {0, 1, .... , Layerl-1 }. The number of codewords (or transport blocks (TB)) that can be transmitted on each layer of LayerNum is represented by Ncwreport, and the codeword is represented by CW(i), where {0,1,...., Ncwreport-l }. User device recently The reported channel quality indication information is represented by CQIreport(i), where {0,1,...., Ncwreport-l }„ In addition, the information reported by the user equipment in this step also includes the current transmission time interval (TTI, Transmission Time). Interval).

 For the LTE system, the correspondence between the number of layers and the codeword is as shown in Table 1 and Table 2: For the MIMO channel of the 2 transmit antenna 2 receive antenna, the correspondence between the number of layers and the codeword is as shown in Table 1, for 4 The transmitting antenna 4 receives the MIMO channel of the antenna, and the correspondence between the number of layers and the codeword is as shown in Table 2.

 Table 2

 In step 102, the base station performs adaptive processing on the Layer 1 to obtain the number of layers of the adaptively processed layer used by the current TTI of the user equipment, and each layer is represented by La(i), where {0, 1, ... ., Layer2-1 }„

For the LTE system, the location mapping relationship between the layer number and the layer is as shown in Table 1 and Table 2: 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 4 The transmitting antenna 4 receives the MIMO channel of the antenna, and the positional mapping relationship between the number of layers and the layer is as shown in Table 2. In step 103, the base station compares the sizes of Layer1 and Layer2, calculates the frequency efficiency SpecEffa of each layer of Layer2 according to the comparison result and CQIreport, and further determines the spectral efficiency on the codeword according to the spectral efficiency and spectral efficiency on the codeword. The mapping relationship with the MCS determines the MCS on the codeword.

 In this step, the base station determines the codewords on the layers corresponding to the Layer 2 according to the correspondence between the number of layers and the codewords, obtains the spectral efficiency SpecEffa of each layer where the codewords are located, and performs spectral efficiency of all layers on the same codeword. The average value of SpecEffa is taken as the spectral efficiency of the codeword.

 2 is a specific processing flow of a multiple input multiple output channel adaptive method according to an embodiment of the present invention. As shown in FIG. 2, the method includes the following steps:

 In step 201, the base station receives and stores the Layer1 and channel quality indication information CQIreport of the channel indicated by the rank indication RI recently reported by the user equipment.

 In this step, the Layer1 is the number of layers of the layer indicated by the rank indicating RI, and each layer is represented by Lr(i), where ie {0,1,...., Layerl-1 }„ Layerl The number of codewords (or TB blocks) that can be transmitted on each layer is represented by Ncwreport, and the codeword is represented by CW(i), where ie {0,1,...., Ncwreport-l }„ recently reported by the user equipment The channel quality indication information is represented by CQIreport(i), where {0, 1, ..., Ncwreport-l }. In addition, the information reported by the user equipment in this step also includes the current Transmission Time Interval (TTI).

In step 202, the base station performs adaptive processing on the Layer 1 to obtain Layer 2 used by the current TTI of the user equipment, where the Layer 2 is the number of layers of the layer after the adaptive processing used by the current UI, and each layer is represented by La(i). Where IE {0,l,...., Layer2-l } _o

In step 203, the base station obtains the frequency efficiency SpecEffr(i) of Layer1 according to the mapping relationship between CQIreport(i) and CQI and spectrum efficiency (the mapping relationship between CQI and frequency efficiency in the LTE system is as shown in Table 3), where { 0,1,...., Layerl-1 }. CQI spectrum efficiency

 Rate

 0 out of range

 Wai

 1 0.1523

 2 0.2344

 3 0.3770

 4 0.6016

 5 0.8770

 6 1.1758

 7 1.4766

 8 1.9141

 9 2.4063

 10 2.7305

 11 3.3223

 12 3.9023

 13 4.5234

 14 5.1152

 15 5.5547

 table 3

 In step 204, the base station compares the sizes of Layer 2 and Layer 1.

 In this step, when Layer2 is equal to Layer1, step 205 is performed, when Layer2 is smaller than

In the case of Layerl, step 206 is performed. When Layer 2 is greater than Layer 1, step 209 is performed.

 In step 206, the mapping relationship between each layer in the Layer 2 and the Layer 2 layers in the Layer 1 is established by mapping, and the frequency efficiency of each layer of the Layer 2 layers in the Layer1 is established.

SpecEffr(i) as the initial spectral efficiency of the corresponding layers in Layer2 SpecEffa_initial(i) is SpecEjfa_initial (i) = SpecEjfr(i) In the embodiment of the present invention, Layer 2 layers can be selected in order from Layer D in the Layer 1 The layers in Layer 2 are mapped in order to obtain the initial spectral efficiency of Layer 2 SpecEffa_initial(i), ie, SpecEffa _ initial(i) = SpecEffr(i). In step 207, the spectral efficiency SpecEffr(i) of the remaining layers in Layer1 is calculated to obtain the incremental spectral efficiency deltaSpecEff of Layer 2. In the embodiment of the present invention, when the previous step selects Layer 2 layers from Layer 1 and layers in Layer 2 in order from the previous step, the remaining a* ∑ SpecEjfrii in Layer 1 can be used.

The spectral efficiency of the (Layerl-Layer2) layer is calculated using the formula te3⁄4^cE# = ~

The Layer! line calculation yields the incremental frequency efficiency deltaSpecEff of Layer2, where "is a weighting factor and takes the value of ^e (o' ¹ ] (a value greater than 0 and less than or equal to 1).

 In step 208, the spectral efficiency SpecEffa(i) of the Layer 2 is obtained by summing the SpecEffa_initial(i) and deltaSpecEff, ie, SpecEjfaii) = SpecEjfa_initial) + deltaSpecEff. β* ∑ SpecEjfrii)

 In step 209, the formula 2⁄4^ (0 =—— '- is calculated to obtain the layer 2

Layer! Spectral efficiency SpecEffa(i), where is the weighting factor, taking the value ^e ' ¹ ] (a value greater than 0 and less than or equal to 1).

 In step 210, according to the correspondence between the number of layers and the codeword (see Table 1 and Table 2), the codeword corresponding to Layer2 and the layer on the codeword are determined, thereby obtaining the spectral efficiency of each layer on the codeword SpecEffa And the average of the spectral efficiency SpecEffa of all layers on the same codeword is taken as the frequency efficiency on the codeword.

 In step 211, the MCS of the codeword is determined according to the spectral efficiency on the codeword and the mapping relationship between the spectral efficiency and the MCS.

 In this step, the mapping relationship between the spectrum efficiency and the MCS is as shown in Table 4. Specifically, the MCS corresponding to the spectral efficiency on the codeword and the closest one of the limited spectral efficiencies listed in Table 4 is the MCS on the codeword.

 MCS spectral efficiency

 0 0.2344

 1 0.3057

 2 0.377

3 0.4893 4 0.6016

 5 0.7393

 6 0.877

 7 1.0264

 8 1.1758

 9 1.3262

 10 1.3262

 11 1.4766

 12 1.69535

 13 1.9141

 14 2.1602

 15 2.4063

 16 2.5684

 17 2.5684

 18 2.7305

 19 3.0264

 20 3.3223

 21 3.6123

 22 3.9023

 23 4.21285

 24 4.5234

 25 4.8193

 26 5.1152

 27 5.33495

 28 5.5547

 Table 4

 The above method is applicable to the Large Delay CDD (Cyclic Delay Diversity) transmission mode and the closed-loop MIMO transmission mode. For the large-delay CDD transmission mode, the channel quality indication information CQI on each layer of the channel is close or equal, so the user equipment reports only one CQIreport; for the closed-loop MIMO transmission mode, the channel quality indication information CQI on each layer of the channel is The user equipment may not be close to or unequal, and the user equipment shall perform a CQIreport on each stream in a streaming manner.

 A multiple input multiple output channel adaptive method provided by the present invention will be described in detail below with reference to specific embodiments.

 Embodiment 1:

 Under the MIMO channel of 4 transmit antennas and 4 receive antennas, a closed loop is applied to the user equipment.

MIMO transmission mode, Layerl of the channel represented by the recently reported rank of the user equipment, where Layerl is 3, and recently reported CQIreport is 8 and 5, refer to Figure 3.

 Step 1201: The base station receives and stores Layer1 of the channel indicated by the rank indication recently reported by the user equipment, where the Layer1 is 3, and each layer is Lr(0), Lr(l), and Lr(2); The codeword (or TB block) number Ncwreport is 2, respectively CW(0) and CW(1) (or TB(0) and TB(1)); the channel quality indicator CQIreport(O) received and stored by the base station is 8 , CQIreport(l) is 5.

 Step 1202: The base station adaptively processes Layerl to obtain Layer 2, which is currently used by the user equipment, where Layer2 is 3, and each layer is La(0), La(l), and La(2). Step 1203: The base station obtains the frequency efficiency of the Lr(0) according to the mapping relationship between the CQIreport(i) and the CQI and the spectral efficiency (Table 3), the SpecEffr(O) is 1.9141, and the spectral efficiency SpecEffr(l) of the Lr(l) is 0.8770. The frequency efficiency of the Lr(2) SpecEffr(2) is 0.8770.

 Step 1204: Compare the sizes of Layer 2 and Layer 1 . Since Layer 2 and Layer 1 are equal, step S 1205 is performed. Language efficiency SpecEffr(i). That is, the frequency efficiency of La(0) is SpecEffa(0)=SpecEffr(0)=1.9141,

The spectral efficiency of La(l) is SpecEffa(l)=SpecEffr(l)=0.8770 and the spectral efficiency of La(2) is

SpecEffa(2)= SpecEffr(2)=0.8770, perform step SA210.

 Step 1210: Determine, according to the correspondence between the number of layers and the codeword (see Table 1), the codeword corresponding to Layer 2 and the layer on the codeword, thereby obtaining the spectral efficiency SpecEffa of each layer on each codeword, and the same code The average of the spectral efficiency SpecEffa of all layers on the word is taken as the spectral efficiency on the codeword. That is, the layer where CW(0) is located is La(0), so the spectral efficiency on CW(0) is SpecEffa(O)

=1.9141, the layer where the codeword CW(1) is located is La(l) and La(2), so the spectral efficiency on CW(1) is (SpecEffa(l)+ SpecEffa(2))/2=(0.8770+ 0.8770)/2=0.8770.

 Step 1211: Determine the MCS on the codeword according to the spectral efficiency on the codeword and the mapping relationship between the spectral efficiency and the MCS (see Table 4). That is, the frequency efficiency on the code word CW(0) is 1.9141 and the table

The frequency efficiency of 1.9141 is the closest, and the MCS corresponding to the frequency efficiency of 1.9141 is 13. Therefore, the MCS on the codeword CW(0) is 13. Similarly, the spectral efficiency on the codeword CW(1) is 0.8770. It is closest to the frequency efficiency 0.8771 in Table 4, and the MCS corresponding to the frequency efficiency 0.877 is 6, so the MCS on the codeword CW(1) is 6.

 Embodiment 2:

 In the MIMO channel of the 4 transmit antenna and the 4 receive antenna, the user equipment adopts a large delay CDD transmission mode, and the rank indicator of the recently reported rank of the user equipment indicates the Layer1 of the channel, where Layer1 is 4 and the recently reported CQIreport is 7. Refer to Figure 4.

 Step 2201: The base station receives and stores Layer1 of the channel indicated by the rank indication recently reported by the user equipment, where Layer1 is 4, and each layer is Lr(0), Lr(l), Lr(2), and Lr(3); The number of codewords (or TB blocks) on Layerl is 2, respectively CW(0) and CW(1) (or TB(0) and TB(1)); the channel quality indicator received and stored by the base station CQIreport(O) ) is 7, CQIreport(l) is 7.

 Step 2202: The base station adaptively processes Layerl to obtain Layer 2, which is currently used by the user equipment, where Layer 2 is 2, and each layer is La(0) and La(l). Step 2203, the base station obtains the frequency efficiency of the Lr(0) according to the mapping relationship between the CQIreport(i) and the CQI and the spectral efficiency (Table 3), the SpecEffr(O) is 1.4766, and the spectral efficiency SpecEffr(l) of the Lr(l) is 1.4766. The frequency efficiency of the Lr(2) SpecEffr(2) is 1.4766, and the frequency efficiency of the Lr(3) SpecEffr(3) is 1.4766.

 In step 2204, the size of Layer 2 and Layer 1 is compared. Since Layer 2 is smaller than Layer 1, step S2206 is performed.

In step 2206, a mapping relationship between each layer in the Layer 2 and Layer 2 layers in the Layer 1 is established by mapping, and the frequency efficiency SpecEffr(i) of each layer of the Layer 2 layers in the Layer1 is used as Layer 2 Corresponding to the initial spectral efficiency SpecEffa_initial(i) of each layer. In this embodiment, Lr(0) and Lr(l) and L(0) and La corresponding to Layer2 are selected among Lr(0), Lr(l), Lr(2) and Lr(3) corresponding to Layer1. (l) Perform mapping to obtain initial spectral efficiency of La(0) SpecEffa_initial(0)=SpecEffa(0)=1.4766, initial spectral efficiency of La(l) SpecEffa_initial(l)=SpecEffa(l)=1.4766. Delta2's incremental spectral efficiency deltaSpecEff.

 This embodiment uses the formula deltaSpecEjf = deltaSpecEff=l.03362 for the spectral efficiency of the remaining Lr(2) and Lr(3) in Layer 1, where "=0.7.

 Step 2208, summing the SpecEffa_initial(i) and deltaSpecEff, that is, SpecEffa(i)=SpecEffa_initial(i)+deltaSpecEff, obtaining the spectral efficiency SpecEffa(i) of the Layer2, that is, the frequency efficiency of the La(0) layer is SpecEffa. (0) = 2.51022, the spectral efficiency of the La(l) layer is SpecEffa(l) = 2.51022.

 Step 2210: Determine, according to the correspondence between the number of layers and the codeword (see Table 2), the codeword corresponding to Layer2 and the layer on the codeword, thereby obtaining the spectral efficiency of each layer on each codeword SpecEffa,

The layer where CW(0) is located is La(0), so the frequency efficiency on CW(0) is SpecEffa(O)=2.51022, and the layer where codeword CW(1) is located is La(l), so CW(1) The frequency efficiency on the basis is SpecEffa(l) = 2.51022.

 Step 2211: Determine the MCS on the codeword according to the spectral efficiency on the codeword and the mapping relationship between the spectral efficiency and the MCS (see Table 4). That is, the frequency efficiency 2.51022 on the codeword CW(0) is closest to the frequency efficiency 2.5684 in Table 4, and the MCS corresponding to the frequency efficiency 2.5684 is 16, so the MCS on the codeword CW(0) is 16. Similarly, the frequency efficiency 2.51022 on the codeword CW(1) is closest to the frequency efficiency 2.5684 in Table 4, and the MCS corresponding to the frequency efficiency 2.5684 is 16, therefore, the codeword CW(1) The MCS is 16.

 5 is a block diagram of a multi-input multi-output channel adaptive apparatus according to an embodiment of the present invention, and FIG. 6 is a detailed refinement diagram of an MCS determining module in the apparatus shown in FIG. 5, which is described in detail below with reference to FIG. 5 and FIG. .

The apparatus includes a layer number and channel quality indication information storage module 11, a layer number adaptive processing module 12, and an MCS determination module 13. The MCS determining module 13 further includes a layer spectral efficiency calculation sub-module 131, a codeword spectral efficiency calculation sub-module 132, and a spectrum efficiency and MCS mapping. The injection module 133.

 The layer number and channel quality indication information storage module 11 receives and stores the Layer1 and channel quality indication information CQIreport of the channel indicated by the rank indication RI reported by the user equipment, and sends it to the MCS determination module 13, and the layer number adaptive processing module 12 performs Layerl on the Layer 1 The adaptive processing is performed to obtain the Layer 2 currently used by the user equipment, and the Layer 2 is sent to the MCS determining module 13.

The spectral efficiency calculation sub-module 131 of the MCS determination module 13 compares the sizes of Layer2 and Layer1, and determines the spectral efficiency of the Layer2 according to the comparison result and CQIreport SpecEffa(i), wherein when Layer2 is equal to Layer1, the spectral efficiency of the Layer2 is SpecEffa ( i) The spectral efficiency of the Layer1 is 3⁄4^ ^c£ K0; when Layer2 is smaller than Layer1, the Layer 2 layer is randomly selected from Layer1 to perform mapping with Layer2 to obtain the initial spectral efficiency of Layer2, SpecEffa_initial(i). ¹ ^ ^ ^Ζ (0 = ^eCjE # ^r (0, then calculate the spectral efficiency SpecEffri^ of the remaining layers in Layer1 to get the incremental spectral efficiency deltaSpecEff of _Layer2 , and finally sum the above SpecEffa_initial(i) and deltaSpecEff to SpecEjfaii) = SpecEffa _ initialii) + deltaSpecEjf to get the spectral efficiency SpecEffa(i) of the Layer2; when Layer2 is greater than Layer1, use the formula β* ∑ SpecEj r(j)

 SpecEjfa(i) =—— ^ Calculate the spectral efficiency of the Layer 2 SpecEffa(i) , β is

 Layerl

The weighting factor; the codeword spectral efficiency calculation sub-module 132 determines the codeword corresponding to Layer2 according to the frequency efficiency SpecEffa of the layer2 obtained by the spectral efficiency calculation sub-module 131 of the layer and the correspondence between the layer and the codeword, thereby obtaining each code. The frequency efficiency SpecEffa of each layer where the word is located, and the average value of the spectral efficiency SpecEffa of all layers on the same codeword is used as the spectral efficiency on the codeword, and the spectral efficiency on the codeword is sent to the spectral efficiency. And the MCS mapping sub-module 133; the spectral efficiency and MCS mapping sub-module 133 determines the MCS on the codeword based on the spectral efficiency and spectral efficiency on the codeword obtained by the sub-module 132 according to the codeword spectral efficiency and the MCS and the mapping relationship. In summary, the present invention obtains the Layer 2 used by the current TTI by adaptively processing the layer in the Layer 1 of the channel indicated by the rank indication RI reported by the user equipment, and determines the adaptive layer according to the obtained Layer 2 and Layer 1 and CQIreport. The MCS on the codeword better realizes the full utilization of the MIMO channel capacity.

 Although the invention has been described in detail above, the invention is not limited thereto, and various modifications may be made by those skilled in the art in accordance with the principles of the invention. Therefore, modifications made in accordance with the principles of the present invention should be construed as falling within the scope of the present invention.

Claims

Claim  A method for multi-input and multi-output channel adaptation, comprising the following steps: A. A base station receives and stores a first layer number Layer1 and channel quality indication information of a channel indicated by a rank indication RI recently reported by a user equipment. CQIreport;  B. The base station performs adaptive processing on Layerl to obtain the second layer number of Layer 2 used by the user equipment at the current transmission time interval TTI;  C. The base station compares the sizes of the Layer 2 and the Layer 1, and calculates the spectral efficiency of the layers of the Layer 2 according to the comparison result and the CQIreport SpecEffa; according to the preset number of layers and the spectral efficiency SpecEffa of each layer on the codeword, And the average value of the spectral efficiency SpecEffa of all layers on the same codeword is used as the frequency efficiency on the codeword; the MCS on the codeword is determined according to the frequency efficiency on the codeword and the mapping relationship between the spectral efficiency and the modulation coding mode MCS. . 2. The method according to claim 1, wherein in step C, calculating the frequency efficiency of the Layer 2 according to the comparison result and the CQIreport, the SpecEffa is specifically:  Determining the mapping according to the mapping relationship between the CQIreport and the preset CQI and spectral efficiency The spectral efficiency of Layerl SpecEffr(i) , where i e { 0, 1 , .... , Layerl-1 };  Calculating the frequency efficiency SpecEffa(i) of the Layer 2 according to the comparison result and the SpecEffr(i), where i e {0,1,...., Layer2-1 }.  3. The method according to claim 2, wherein the comparison result is a Layer 2 spectral efficiency SpecEffr(i); wherein i e {0, 1, . . . , Layerl-1 }.  4. The method according to claim 2, wherein the comparison result is Layer2 β* ∑ SpecEj r(j) When larger than Layer1, calculate the Layer 2 by using the formula 3⁄4^ (0 = - ^} - Layer! Spectral efficiency SpecEffa(i), where is the weighting factor, with a range of 0 < 1. The method according to claim 2, wherein when the comparison result is that Layer 2 is smaller than Layer 1, the mapping between the layers in the Layer 2 and the Layer 2 layers in the Layer 1 is established by mapping, The frequency efficiency SpecEffr(i) of each layer of the Layer 2 layers in the Layer1 is the initial spectral efficiency of the corresponding layers in Layer 2 SpecEffa_initial(i); the spectral efficiency of the remaining layers in the Layer1 SpecEffr(i) Performing calculations to obtain the incremental spectral efficiency deltaSpecEff of the Layer 2;  The SpecEffa_initial(i) and deltaSpecEff are summed to obtain the spectral efficiency SpecEffa(i) of each layer of the Layer 2.  The method according to claim 5, wherein the calculating the spectral efficiency SpecEffr(i) of the remaining layers in the Layer1 to obtain the incremental spectral efficiency of the Layer 2 to obtain the increment of the Layer 2 The spectral efficiency deltaSpecEff, where "is a weighting factor, with a range of 0 < "1.  A device for multi-input and multi-output channel adaptation, the device comprising: a layer number and channel quality indication information storage module, configured to receive and store a channel indicated by a rank indication RI recently reported by a user equipment Layerl and channel quality indication information CQIreport, and send;  The layer number adaptive processing module is configured to perform adaptive processing on the Layerl to obtain the Layer 2 used by the current TTI of the user equipment;  An MCS determining module, configured to compare sizes of the Layer 2 and the Layer 1, and calculate a spectral efficiency SpecEffa of each layer of the Layer 2 according to the comparison result and the CQIreport, and then according to a preset correspondence between a number of layers and a codeword Determining the codeword corresponding to the Layer 2 and the frequency efficiency on the codeword, and determining the MCS on the codeword according to the frequency efficiency on the codeword and the mapping relationship between the frequency efficiency and the MCS. The device according to claim 7, wherein the MCS determining module further comprises: a spectral efficiency calculation sub-module of the layer, configured to calculate a spectral efficiency SpecEffa of the Layer 2, when the comparison result is that Layer 2 is equal to Layer 1, the spectral efficiency SpecEffa(i) of the Layer 2 is sequentially the frequency efficiency of the Layer1 SpecEffr(i); where ie {0,1,...., Layerl-1 }; When the comparison result is that Layer2 is greater than Layer1, use the formula β* ∑ SpecEj r(j)  SpecEjfaii) =—— ^ Calculate the spectral efficiency of the Layer 2 SpecEffa(i), where Layerl is a weighting factor with a value range of 0 <1; when the comparison result is Layer 2 is less than Layerl

 The initial spectral efficiency SpecEffa_initial(i) of Layer2 is calculated by calculating the spectral efficiency SpecEffr(i) of the remaining layers in the Layer1 to obtain the incremental frequency efficiency deltaSpecEff of the Layer2, and summing the SpecEffa_initial(i) and deltaSpecEff Obtaining the spectral efficiency SpecEffa(i) of each layer of the Layer 2; a codeword spectral efficiency calculation sub-module, configured to calculate a spectral efficiency of the Layer 2 obtained by the sub-module according to the spectral efficiency of the layer, SpecEffa(i), and a preset correspondence between the number of layers and the codeword

 The spectrum efficiency and MCS mapping sub-module is configured to determine the MCS on the codeword according to the spectral efficiency of the codeword obtained by the sub-module and the mapping relationship between the spectral efficiency and the MCS. The device according to claim 8, wherein the spectral efficiency calculation sub-module of the layer determines the spectrum efficiency of each layer of the Layer 1 according to the mapping relationship between the CQIreport and the preset CQI and the spectral efficiency ^. ^^'). 10. The apparatus according to claim 8, wherein the frequency efficiency calculation sub-module of the layer establishes a map by mapping when the comparison result is that the Layer 2 is smaller than the Layer1. Corresponding relationship between layers in Layer 2 and Layer 2 layers in Layer 1. The spectral efficiency SpecEffr(i) of each layer of Layer 2 layers in Layer1 is used as the initial spectral efficiency of corresponding layers in Layer 2. SpecEffa_initial(i); factor", then divide by Layer2 to get the incremental frequency efficiency deltaSpecEff of the Layer 2, where "is a weighting factor, the value range is 0 <"1.