CN101777965B - Channel state information feedback method and user terminal - Google Patents

Abstract

The invention provides a kind of channel state information feedback method and user terminal.Relate to digital communicating field；Solve and lack a kind of problem reporting the mechanism of channel condition information comprehensively and effectively in the system of SU MIMO and MU MIMO switching at runtime.The method includes: under single transmission mode, and UE sends channel condition information to network side, and described channel condition information includes the information indicating the best transport layer of channel quality.The technical scheme that the present invention provides is be applicable to LTE and LTE A system.

Description

Channel state information feedback method and user terminal

Technical field

The present invention relates to digital communicating field, particularly relate to a kind of channel state information feedback method and user terminal.

Background technology

In long evolving system (LTE:Long Term Evolution), the information of reflection down physical channel state (CSI:Channel State Information) has three kinds of forms: channel quality indicates (CQI:Channels quality Indication), pre-coding matrix instruction (PMI:Pre-coding MatrixIndicator), order instruction (RI:Rank Indicator)。

CQI is the index weighing down channel quality quality.In 36-213 agreement CQI with 0～15 integer value Representing, representing different CQI grades respectively, different CQI correspond to respective modulation system and encoder bit rate (MCS), altogether Divide 16 kinds of situations, 4 bit informations can be used to represent, as shown in table 1.

PMI refers to only under this emission mode of Closed-Loop Spatial Multiplexing, and terminal (UE:UserEquipment) is according to recording Channel quality tell base station (eNB:eNode B) should use which type of pre-coding matrix to issue this UE PDSCH believe Road carries out precoding, and RI is then for the UE number of plies to base station feedback downlink transfer.The feedback granularity of PMI can be whole bandwidth Feed back a PMI, it is also possible to feed back PMI according to subband.

RI is for describing the number of space independent channel, the order of respective channels response matrix.At Open-Loop Spatial Multiplexing and closing Under annular space multiplexer mode, need UE to feed back RI information, need not under other patterns feed back RI information.The sum of ranks layer of channel matrix Number correspondence.

Transport layer is the concept of multiple antennas in LTE and LTE-A " layer ", and in representation space multiplexing, effective independent channel is individual Number, with antenna port one_to_one corresponding in version 10, wherein in version 10, antenna port is logic port, and the sum of transport layer is just It is RI.It addition, in IEEE802.16m, layer is corresponding with " MIMO stream " concept, has identical physical meaning.

Relation between table 1CQI index and MCS

In LTE system, the feedback of CQI/PMI, RI can be periodically to feed back, it is also possible to is acyclic feedback, Concrete feedback is as shown in table 2.Wherein, for the CQI/PMI of periodic feedback, for RI, if UE need not send data, The then CQI/PMI of periodic feedback, RI row physically controls channel (PUCCH:Physical Uplink Control Channel) transmit with form 2/2a/2b (PUCCH format2/2a/2b) on, if UE needs to send data, then CQI/ PMI, RI transmit during row shares channel (PUSCH:Physical Uplink Shared Channel) physically；For non-week The CQI/PMI of phase property feedback, for RI, only transmits on PUSCH.

Table 2 periodic feedback and aperiodicity are fed back deserved uplink physical channel

Scheduling method	Periodically CQI channel	Aperiodicity CQI channel
			Frequency non-selective	PUCCH
Frequency selectivity	PUCCH	PUSCH

In LTE system, under different transmission modes, periodicity CQI/PMI of PUCCH channel, the load of RI (payload size) is different, but the load of maximum is 11 bits.During periodic feedback, first use Reed-Muller (20, A) M (M ＜=11) bit CQI/PMI, the RI coding that will feed back, is then modulated the bit after coding, with PUCCH format The form transmission of 2/2a/2b.

Advanced long-term evolution system (LTE-A:Long Term as the evolution standard of LTE EvolutionAdvanced) need to support bigger system bandwidth (reaching as high as 100MHz), and need to improve average frequency spectrum Efficiency and the spectrum efficiency of Cell Edge User, to this end, lte-a system introduces a lot of new technique: how defeated (1) descending high-order is Enter multi output (MIMO:Multiple Input MultipleOutput), descending 4 antenna transmission that could support up of LTE system, and The introducing of high-order mimo makes the descending transmission that could support up 8 antennas of lte-a system, then the dimension of channel state matrix increases； (2) cooperative multipoint transmission (CoMP:Coordinated multiple point transmission), this technology utilizes exactly The cooperation transmission of multiple cell transmission antennas, then UE may need to feed back the channel condition information of multiple community.

Using many antennas at transmitting terminal (eNB), we can improve transfer rate, i.e. in the way of taking spatial reuse Different data are launched in different antennae position on the running time-frequency resource that transmitting terminal is identical, also use many skies at receiving terminal (UE) Line, the resource of all antennas can be distributed on same user in the case of single user by us, and this transmission form is called list User MIMO (SU-MIMO), additionally the resource in different antennae space also can be distributed to difference in the case of multi-user by us User, this transmission form is called multiuser MIMO (MU-MIMO).Under single transmission mode, eNB is according to the channel shape reported State information can be dynamically selected transmission or the transmission of MU-MIMO of descending SU-MIMO, we term it SU/MU MIMO Switching at runtime.

Once Single User MIMO and the general processing procedure of multiuser MIMO switching at runtime transmission mode described below:

First, transmitting terminal sends pilot tone to user terminal, tests downlink channel condition, user terminal root for user terminal Estimating down channel according to the pilot frequency information received, user terminal determines the form of feeding back channel state information, and reporting channel Status information, then by eNB according to the channel condition information reported, is dynamically selected transmission or the MU-of descending SU-MIMO The transmission means of MIMO, and communicate according to the transmission means selected.

For Single User MIMO and multiuser MIMO switching at runtime transmission mode, on the one hand need to keep backwards compatibility, To support SU-MIMO as priority principle, the feedback form of the CQI/PMI/RI of the most compatible R8, on the other hand, before needing to consider To compatibility, it is considered to the support to MU-MIMO and COMP, it is ensured that new technique has acceptable performance.And in prior art Lack a kind of mechanism reporting channel condition information comprehensively and effectively in the system of SU-MIMO and MU-MIMO switching at runtime, make Become the down channel selecting to use when UE sends data that base station cannot be correct, so cause not supporting at SU-MIMO and Being switched fast in MU-MIMO both transmission forms, reduces system work efficiency.

Summary of the invention

The invention provides feedback method and the user terminal of a kind of channel condition information, solve shortage a kind of at SU- The problem reporting the mechanism of channel condition information comprehensively and effectively in the system of MIMO and MU-MIMO switching at runtime.

A kind of channel state information feedback method, including:

Under single transmission mode, UE sends channel condition information to network side, and described channel condition information includes referring to Show the information of the best transport layer of channel quality.

Further, described single transmission mode is SU-MIMO transmission mode, or MU-MIMO transmission pattern, or SU- The mixed transmission modes of MIMO and MU-MIMO.

Further, the information of the described best transport layer of instruction channel quality is preset best transport layer fixed position, Described UE also included before network side sends the step of channel condition information:

Arranging best transport layer fixed position, being specially fixing ground floor is best layer, or fixes first and second layer for Good layer.

Further, the information of the described best transport layer of instruction channel quality is CQI, and described CQI includes respectively The CQI of transport layer, described UE also included before network side sends the step of channel condition information:

According to the CQI of each transport layer, generate CQI.

Further, the information of the described best transport layer of instruction channel quality be different transport layer set average CQI and Differential CQI between the average CQI of each transport layer and belonging transport layer set, described UE sends channel to network side Also include before the step of status information:

Transport layer is divided at least two transport layer set；

Seek the average CQI of each transport layer set respectively；

According to the average CQI of each transport layer set, ask each transport layer and belonging transport layer set average CQI it Between differential CQI.

Further, the information of the described best transport layer of instruction channel quality is up indication signaling, and described UE is to network Also include before the step of side transmission channel condition information:

UE judges best transport layer, and generates up indication signaling according to judged result, and instruction network side should according to use Best transmission layer transmission data.

Further, described channel condition information includes up indication signaling and the average CQI of each transport layer set, described UE also included before network side sends the step of channel condition information:

Transport layer is divided at least two transport layer set by UE；

Seek the average CQI of each transport layer set respectively；

Described UE, from transport layer set the highest for average CQI, chooses best transport layer, and generates according to choosing result Row indication signaling.

Present invention also offers a kind of UE, under single transmission mode, including:

Information feedback module, for sending channel condition information to network side, described channel condition information includes instruction letter The information of road transport layer best in quality.

Further, above-mentioned UE also includes:

First information generation module, for according to preset best transport layer fixed position, generates channel condition information；

Second information transmission modular, for the CQI according to each transport layer, obtains CQI, and according to this CQI, raw Become channel condition information；

Calculate the average of the average CQI of different transport layer set and each transport layer and belonging transport layer set Differential CQI between CQI, generates channel condition information according to result of calculation；

3rd information transmission modular, is used for generating up indication signaling, and according to this up indication signaling, generates channel shape State information；

4th information transmission modular, for according to up indication signaling and the average CQI of each transport layer set, generates channel Status information.

The embodiment provides a kind of channel state information feedback method and user terminal, at user terminal to net When network side sends channel condition information, carrying the instruction selecting best transport layer in this information, instruction network side passes through institute State best transport layer and issue data to this user terminal, so, when network side determines to use MU-MIMO, it is possible to according to this letter The instruction selecting best transport layer in channel state information, quickly determines best transport layer, improve efficiency of transmission and Transmission quality, solves shortage and reports channel status letter comprehensively and effectively in the system of SU-MIMO and MU-MIMO switching at runtime The problem of the mechanism of breath.

Accompanying drawing explanation

The flow chart of a kind of channel state information feedback method that Fig. 1 provides for embodiments of the invention five；

The flow chart of a kind of channel state information feedback method that Fig. 2 provides for embodiments of the invention six；

The channel condition information structural representation that Fig. 3 is used by embodiments of the invention six；

The flow chart of a kind of channel state information feedback method that Fig. 4 provides for embodiments of the invention seven；

The structural representation of the channel condition information that Fig. 5 is used by embodiments of the invention seven；

The flow chart of a kind of channel state information feedback method that Fig. 6 embodiments of the invention eight provide；

The structural representation of a kind of UE that Fig. 7 provides for embodiments of the invention；

The structural representation of a kind of user terminal that Fig. 8 provides for another embodiment of the present invention.

Detailed description of the invention

In order to obtain higher peaks spectrum efficiency, in lte-a system, descending needs supports Single User MIMO and multi-user The switching at runtime of MIMO, on the one hand, the feedback control signaling of channel information needs to keep backwards compatibility, to support SU-MIMO For priority principle, the feedback form of the CQI/PMI/RI of the most compatible existing Release8；On the other hand, channel information is anti- Feedback controls signaling to be needed to consider forward compatibility, it is considered to the support to MU-MIMO and COMP, it is ensured that new technique has and can accept Performance.

In order to realize reporting channel condition information comprehensively and effectively in the system of SU-MIMO and MU-MIMO switching at runtime, The embodiment provides a kind of channel state information feedback method.

Below embodiments of the invention one are illustrated.

Embodiments providing a kind of channel state information feedback method, the method includes: at single transmission mould Under formula, UE sends channel condition information to network side eNB, and described channel condition information includes indicating the best transport layer of channel quality Information.

Further, described single transmission mode is SU-MIMO, or the transmission mode of MU-MIMO, or SU-MIMO and MU- The mixed transmission modes of MIMO.

Further, the information of the described best transport layer of instruction channel quality, referred to by the method for fixing best layer position Show, if fixing ground floor is best layer, or fix first and second layer for best layer.

Further, the information of the described best transport layer of instruction channel quality is specially right unitary matrice pre-of channel matrix Encoder matrix (PMI), before described UE sends the step of channel condition information to network side, also includes:

Described UE estimates the channel matrix obtained according to channel, and UE determines pre-coding matrix index from preset code book PMI so that the first transport layer of described PMI instruction has a best channel quality, or make the first He that described PMI indicates Transport layer corresponding to the second transport layer has best and second-best channel quality.

Further, described UE estimates the channel matrix obtained according to channel, determines and described biography from preset code book The unitary matrice of defeated layer coupling includes:

Described channel matrix is carried out singular value decomposition, obtains right unitary matrice and the diagonal matrix of this channel matrix, described right In the battle array of angle, the singular value of first row is maximum, and the singular value that each row are corresponding is reduced successively by each row sequence；

From preset code book, select one with the described immediate unitary matrice of right unitary matrice as with described transport layer The unitary matrice joined, the index of its correspondence is exactly pre-coding matrix index.

Further, described UE estimates the channel matrix obtained according to channel, determines and described biography from preset code book The unitary matrice of defeated layer coupling includes:

Described channel matrix is carried out singular value decomposition, obtains the right unitary matrice of this channel matrix；

Each column vector of described right unitary matrice is carried out fully intermeshing, and combination to various sequences quantifies respectively；

Select minimum the combining as final right unitary matrice of quantization error, from preset code book, select one and institute State the immediate unitary matrice of right unitary matrice as the unitary matrice mated with described transport layer.

More specifically, such as, in lte-a system, under the transmission mode of SU/MU MIMO switching at runtime, UE determines 4 transport layers, fixing first transport layer is best transport layer, or fixes first and second transport layer good biography best, the most secondary Defeated layer.

Below embodiments of the invention two are described in detail.

A kind of channel state information feedback method includes: under single transmission mode, and UE sends channel to network side eNB Status information, described channel condition information includes the information indicating the best transport layer of channel quality.

The information of the best transport layer of instruction channel quality described further refers to that CQI, UE are determined often by CQI Which layer the channel quality information CQI of individual transport layer, indicate best according to the CQI of each transport layer, and UE be by CQI Send to eNB.

Further, described CQI, the transport layer maximum including the CQI of each layer, CQI is exactly best layer.

Further, the average CQI of different transport layer set and each transport layer and belonging transport layer set Differential CQI between average CQI.The transport layer that in average transport layer set maximum for CQI, differential CQI is maximum is exactly best layer.

Further, first UE determines that total number of plies of Single User MIMO is r, and then UE determines (r/2) transmission from 1 to ceil Average channel quality CQI_1 of layer and average channel quality CQI_2 from foor (r/2) to r transport layer, and determine from 1 to Ceil (r/2) each transport layer differential CQI relative to CQI_1 with from floor (r/2) to the r each transport layer difference relative to CQI_2 Divide CQI.Here, r is the positive integer more than 1, and ceil represents and rounds up, and floor represents and rounds downwards.

More specifically, such as, in lte-a system, under the transmission mode of SU/MU MIMO switching at runtime, UE determines 4 transport layers, and each transport layer has CQI, respectively a COI₁、CQI₂、CQI₃And CQI₄.Assume wherein CQI₃It is Big, then would indicate that the 3rd transport layer is best transport layer.Assume wherein CQI₃Maximum and CQI₁Secondary greatly, then just refer to Show that the three, the one transport layers are respectively best and next best transport layer.

Below embodiments of the invention three are described in detail.

A kind of channel state information feedback method includes: under single transmission mode, and UE sends channel to network side eNB Status information, described channel condition information includes the information indicating the best transport layer of channel quality.

Further, the information of the described best transport layer of instruction channel quality refers to newly increase up indication signaling, and UE Up indication signaling is sent reporting described extra up indication signaling to eNB together with other channel condition information.

Further, described channel condition information include increase extra up indication signaling have log2 (combnk (r, 1)) individual bit, instruction is the position of best layer transport layer from 1 to r.Here, total number of plies of Single User MIMO is that r, r are for being more than The positive integer of 1, (n, j) represents in n the number of combinations taking j to combnk, n and j is greater than the positive integer equal to 1 and n is more than or equal to j。

More specifically, such as, in lte-a system, under the transmission mode of SU/MU MIMO switching at runtime, UE determines 8 transport layers, the extra up indication signaling of described increase is made up of 3 bits, respectively b₁, b₂, b₃, different up fingers Show that the implication of signaling is as shown in table 3.

Relation between up indication signaling and best layer that table 3 is extra

B1, b2, b3	The best layer of instruction
		000	First transport layer
001	Second transport layer
		010	3rd transport layer
011	4th transport layer
		100	5th transport layer
101	6th transport layer
		110	7th transport layer
111	8th transport layer

Below embodiments of the invention four are described in detail.

A kind of channel state information feedback method includes: under single transmission mode, and UE sends channel to network side eNB Status information, described channel condition information includes the information indicating the best transport layer of channel quality.

Further, the information of the described best transport layer of instruction channel quality refers to up indication signaling, and UE will report Up indication signaling is sent to eNB together with other channel condition information by described extra up indication signaling.

Further, described channel condition information includes up indication signaling and the average CQI of different transport layer set, institute Stating up indication signaling for indicating the transport layer that in transport layer set maximum for average CQI, channel quality is best is in all layers Best transport layer.

Further, the average CQI of described different transport layer set is the average channel of (r/2) transport layer from 1 to ceil Quality CQI_1 and average channel quality CQI_2 from foor (r/2) to r transport layer.

Further, r=1, when 2, described extra indication signaling number is 0；R=3, when 4, described extra instruction Signaling number is 1；R=5, when 6,7,8, described extra indication signaling number is 2.

Further, if CQI_1 is less than or equal to CQI_2, then preferably transport layer occurs in from foor (r/2) to r transport layer In, the extra up indication signaling of log2 (combnk (ceil (r/2), 1)) individual bit is used to refer to the position of wherein preferably layer； If CQI_1 is more than CQI_2, then preferably transport layer occurs in from 1 to ceil (r/2) transport layer, log2 (combnk (ceil (r/ 2), 1)) the up indication signaling that individual bit is extra is used to refer to the position of wherein preferably layer；Here, first UE determines alone Total number of plies of family MIMO be r, r be the positive integer more than 1, ceil represents and rounds up, and floor represents and rounds downwards, combnk (n, j) represents in n the number of combinations taking j, n and j is greater than the positive integer equal to 1 and n more than or equal to j.

Further, then UE determines average channel quality CQI_1 of (r/2) transport layer from 1 to ceil and from foor (r/ 2) to average channel quality CQI_2 of r transport layer, if CQI_1 is less than CQI_2, then preferably transport layer occurs in from foor (r/2) In r transport layer, the extra up indication signaling of log2 (C (ceil (r/2), 1)) individual bit is used to refer to wherein best layer Position；If CQI_1 is more than or equal to CQI_2, then preferably transport layer occurs in from 1 to ceil (r/2) transport layer, log2 (C (ceil (r/2), 1)) the extra up indication signaling of individual bit is used to refer to the position of wherein preferably layer；Here, UE is first Determine total number of plies of Single User MIMO be r, r be the positive integer more than 1, ceil represents and rounds up, and floor represents and takes downwards Whole, (n, j) represents in n the number of combinations taking j to combnk, n and j is greater than the positive integer equal to 1 and n more than or equal to j.

More specifically, such as, in lte-a system, under the transmission mode of SU/MU MIMO switching at runtime, UE determines 8 transport layers, ground floor to the 4th layer has an average channel quality indication (CQI) information CQI-1, and layer 5 to the 8th layer has one Individual average channel quality indication (CQI) information CQI-2.Channel condition information, except including CQI-1, CQI-2 etc., also includes that one 2 is compared Special extra signaling, is used for indicating that transport layer in different transport layer set maximum.

Assuming CQI-1 ＞ CQI-2, this extra up indication signaling is b₁, b₂, the implication of each up indication signaling such as table 4 Shown in.

Relation between up indication signaling and best layer that table 4 is extra

B1, b2	The best layer of instruction
		00	First transport layer
01	Second transport layer
		10	3rd transport layer
11	4th transport layer

Assuming CQI-2 ＞ CQI-1, this extra signaling is b₁, b₂, the implication of the most each up instruction information such as table 5 institute Show.

Relation between up indication signaling and best layer that table 5 is extra

B1, b2	The best layer of instruction
		00	5th transport layer
01	6th transport layer
		10	7th transport layer

11	8th transport layer

Below in conjunction with the accompanying drawings, embodiments of the invention five are illustrated.

Embodiments of the invention five provide a kind of channel state information feedback method, by taking in channel condition information The instruction that best transport layer is selected by band, solves shortage and reports in the system of SU-MIMO and MU-MIMO switching at runtime comprehensively The problem of the mechanism of effective channel condition information.In the embodiment of the present invention, the instruction selecting best transport layer is specially the tenth of the twelve Earthly Branches The PMI of matrix, network equipment is specially data sending terminal (such as eNB), and UE is specially UE.The method is used to complete channel status The flow process of information feedback is as it is shown in figure 1, include:

Step 101, code book is set at UE and network side；

In the embodiment of the present invention, 16 u vectors near uniform distribution in n-dimensional space that LTE defines when 4 antenna.

N this refers to the size of each u vector, i.e. n=4.Here the meaning is, 16 typical u vectors, quantization means [a₁ a₂ a₃ a₄]^TVector, wherein a₁, a₂, a₃, a₄It is any plural number, and [a₁ a₂ a₃a₄]^T[a₁ a₂ a₃ a⁴]=1.

Householder based on u vector converts expression formula one, generates as shown in table 3 16 code book.

$W_n=I-2u_n{u}_n^H/u_n^H{u}_n$ Expression formula one

Wherein, I is the unit matrix of 4*4, it is assumed that the reception antenna number of certain UE is 4, then have 4 between UE and base station Individual transport layer, therefore order is 4, according to table 3, comprises 16 unitary matrice quantified in code book, the size of each unitary matrice is 4*4, UE and base station have same code book.

The lateral UE of step 102, network sends transport layer pilot reference information, tests downlink channel condition for UE；

Step 103, UE receive the transport layer pilot reference information that network side issues, and carry out transport layer according to this information Channel is estimated；

Step 104, UE estimate the channel matrix obtained according to channel, determine and described transport layer from preset code book The unitary matrice joined；

In step 103, after UE carries out channel estimation to whole transport layers, obtain in channel matrix H, this step, UE root According to expression formula two, H is carried out singular value decomposition (Singular valuedecomposition, SVD), obtain left unitary matrice U, the right side Unitary matrice V and diagonal matrix ∑, and ensure that each singular value in diagonal matrix ∑ meets | σ₁|≥|σ₂|≥|σ₃|≥|σ₄|。

V=[v₁, v₂, v₃, v₄], according to right unitary matrice V, from 16 unitary matrice of described code book, selection one is closest Unitary matrice, obtain the index PMI of this unitary matrice.

$H=\mathrm{U\Σ}{V}^H=[u_1,u_2,u_3{,u}_4]\left[\begin{array}{cccc}{\mathrm{\σ}}_1& 0& 0& 0\\ 0& {\mathrm{\σ}}_2& 0& 0\\ 0& 0& {\mathrm{\σ}}_4& 0\\ 0& 0& 0& {\mathrm{\σ}}_4\end{array}\right]{[v_1{,v}_2,v_3,v_4]}^H$ Expression formula two

By above-mentioned SVD and the determination of singular value order of magnitude relation, it is possible to obtain that there are implicit mapping relations PMI, it is ensured that best 1 or 2 column vectors are always placed on front 1 row or the first two columns of right unitary matrice corresponding for PMI.

Step 105, UE send channel condition information to base station；

In this step, UE sends channel condition information to base station, in this channel condition information, carry PMI, one to two CQI and RI.

So, after base station receives the channel condition information that UE sends, it is possible to according to PMI therein, deposit from this locality The preset code book of storage obtains the unitary matrice of correspondence, and then puts in order according to the column vector set up when arranging code book, determine Best transport layer.

Optionally, at step 104, it is also possible to determine unitary matrice according to following method:

First, UE carries out SVD to H, obtains the right unitary matrice V=[v of channel matrix₁, v₂, v₃, v₄], to described unitary matrice Carry out fully intermeshing in a different order, obtain following may 24 kinds of spread patterns:

V₁=[v₁, v₂, v₃, v₄]

V₂=[v₁, v₂, v₄, v₃]

V₃=[v₁, v₃, v₂, v₄]

V₂₄=[v₄, v₁,₂, v₃]

It is provided with certain arrangement V_h=[v_i, v_j, v_k, v_l], and selection one is closest from 16 unitary matrice of described code book Unitary matriceThe quantization error making first row vector is minimum, the quantization error of secondary series column vector the Two is little, the most satisfiedWherein, i, j, k, l belong to set { 1,2,3,4}, and i, j, k, l are four different numbers.Wherein,Represent vector v i and vectorBetween string away from From,Obtain the index PMI of this unitary matrice.Wherein, h for belong to set 1,2, 3 ..., a positive integer of 24}.In this manner it is possible to obtain the minimum unitary matrice of the quantization error square at the tenth of the twelve Earthly Branches as this UE Battle array.

The precoding codebook of descending 4 antennas of table 6

Below in conjunction with the accompanying drawings, embodiments of the invention six are illustrated.

Embodiments of the invention six provide a kind of channel state information feedback method, by taking in channel condition information The instruction that best transport layer is selected by band, solves shortage and reports in the system of SU-MIMO and MU-MIMO switching at runtime comprehensively The problem of the mechanism of effective channel condition information.In the embodiment of the present invention, the instruction concrete CQI report that best transport layer is selected Accusing, comprise the CQI of whole transport layer in CQI, network equipment is specially data sending terminal (such as base station), and UE is specially UE。

In the embodiment of the present invention, 16 u vectors near uniform distribution in n-dimensional space that LTE defines when 4 antenna.Base Convert expression formula one in the Householder of u vector, generate as shown in table 3 16 code book.

The channel state information feedback method using the embodiment of the present invention to provide completes the flow process of information feedback As in figure 2 it is shown, include:

The lateral UE of step 201, network sends transport layer pilot reference information, tests downlink channel condition for UE；

Step 202, UE receive the transport layer pilot reference information that network side issues, and carry out transport layer according to this information Channel is estimated；

Step 203, UE estimate the channel matrix obtained according to channel, determine and described transport layer from preset code book The unitary matrice joined and the CQI of each transport layer；

In this step, channel, according to expression formula two, is estimated that the channel matrix H obtained carries out SVD, is obtained channel matrix by UE Right unitary matrice V=[v₁, v₂, v₃, v₄], and from 16 unitary matrice of described code book, select an immediate unitary matrice, Index PMI to this unitary matrice.

Now, UE also needs to determine the channel quality indication (CQI) information CQI of the transport layer corresponding to string every in unitary matrice, this Inventive embodiments has four transport layers, so there being 4 CQI.

Step 204, UE send channel condition information to base station；

The channel condition information structure that the embodiment of the present invention is used is as shown in Figure 3.

In this step, UE feedback PMI and 4 CQI is to base station.

After base station receives this channel condition information, it is possible to determine when carrying out MU-MIMO to this UE spendable Good transport layer (transport layer that i.e. maximum CQI value is corresponding).Such as, the CQI of four transport layers is respectively CQI₁、CQI₂、CQI₃With CQI₄, and CQI₂＞ CQI₁＞ CQI₄＞ CQI₃, second column vector v of the rightest unitary matrice V₂It is exactly best column vector, code book The secondary series v of the matrix of middle PMI instruction₂It is exactly v₂Quantized value, eNB can obtain described quantitative information, and then determine best Transport layer is exactly v₂Corresponding transport layer.

It should be noted that according to CQI value from high to low, the quality of each transport layer is also by getting well to secondary, therefore base station is using MU-MIMO, can according to actual needs when UE sends data, and a transport layer or signal that selection signal is best are the most Bar transport layer is transmitted, and this is not construed as limiting by embodiments of the invention.

Additionally, when the number of plies of transport layer is more, the CQI collective data amount of each transport layer is relatively big, needs to take more Bandwidth resources, reduce system transfers efficiency, therefore can be when transmitting the number of plies more (as there are 8 transport layers), UE is first Transport layer is divided into different set.Such as, 8 transport layers being divided into two set, each set comprises four transport layers, asks The average cqi value of each set；Seek the differential CQl values of each transport layer the most respectively, specifically can be by taking CQI and this transmission of transport layer The difference of the average CQI of layer place set obtains differential CQl values, using the differential CQl values of each transport layer as CQI, sends To base station, according to the difference value of each transport layer, base station judges that the channel quality of which transport layer is best, generally, makes even Transport layer maximum for difference value CQI in set the highest for CQI is as the best transport layer of channel quality.

Below in conjunction with the accompanying drawings, embodiments of the invention seven are illustrated.

Embodiments of the invention seven provide a kind of channel state information feedback method, by taking in channel condition information The instruction that best transport layer is selected by band, solves shortage and reports in the system of SU-MIMO and MU-MIMO switching at runtime comprehensively The problem of the mechanism of effective channel condition information.In the embodiment of the present invention, select best transport layer is designated as up finger Showing signaling, the most best column vector index (Best Layer Index, BLI), network equipment is specially data sending terminal (such as eNB), UE is specially UE.

In the embodiment of the present invention, 16 u vectors near uniform distribution in n-dimensional space that LTE defines when 4 antenna.Base Convert expression formula one in the Householder of u vector, generate as shown in table 6 16 code book.

The channel state information feedback method using the embodiment of the present invention to provide completes the flow process of information feedback As shown in Figure 4, including:

The lateral UE of step 401, network sends transport layer pilot reference information, tests downlink channel condition for UE；

Step 402, UE receive the transport layer pilot reference information that network side issues, and carry out transport layer according to this information Channel is estimated；

Step 403, UE estimate the channel matrix obtained according to channel, determine and described transport layer from preset code book The unitary matrice joined and BLI；

In this step, channel, according to expression formula two, is estimated that the channel matrix H obtained carries out SVD, is obtained channel matrix by UE Right unitary matrice V=[v₁, v₂, v₃, v₄] and diagonal matrix ∑, and selection one is closest from 16 unitary matrice of described code book Unitary matrice, obtain the index PMI of this unitary matrice.

In addition it is also necessary to determine that the BLI of this UE, BLI represent that maximum singular value is absolute in the unitary matrice that PMI index is corresponding The column index of the column vector that value is corresponding.

Such as, there are 2 bit index, 00 represents v₁Being best column vector, 01 represents v₂It is best column vector, 10 represent v₃Being best column vector, 11 represent v₄Being best column vector, transport layer corresponding to best column vector is best Transport layer.

The index of multiple preferable column vector can also be indicated in BLI simultaneously, as exhausted in regulation BLI correspondence maximum singular value To value and the column index of two column vectors of second largest singular value absolute value.Such as, there are 3 bit index, 000 represents v₁, v₂Being preferable two column vectors, 001 represents v₁, v₃Being preferable two column vectors, 010 represents v₁, v₄It it is preferable two Column vector, 011 represents v₂, v₃Being preferable two column vectors, 100 represent v₂, v₄Being preferable two column vectors, 101 represent v₃, v₄It is preferable two column vectors.

It should be noted that the best column vector corresponding to each value of BLI is just to appoint when system initialization , i.e. eNB and UE both knows about best column vector and the corresponding transport layer that BLI value represents.

Step 404, UE send channel condition information to eNB；

The channel condition information structure that the embodiment of the present invention is used is as shown in Figure 5.

After eNB receives this channel condition information, it is possible to determine when carrying out MU-MIMO to this UE spendable best Transport layer (i.e. BLI index point to transport layer).

Below in conjunction with the accompanying drawings, embodiments of the invention eight are illustrated.

Embodiments of the invention eight provide a kind of channel state information feedback method, by taking in channel condition information The instruction that best transport layer is selected by band, solves shortage and reports in the system of SU-MIMO and MU-MIMO switching at runtime comprehensively The problem of the mechanism of effective channel condition information.In the embodiment of the present invention, the instruction selecting best transport layer is specially BLI And CQI, the average CQI (average channel quality) of each transport layer set is included in CQI, network equipment is specially Data sending terminal (such as eNB), UE is specially UE.

In the embodiment of the present invention, 16 u vectors near uniform distribution in n-dimensional space that LTE defines when 4 antenna.Base Convert expression formula one in the Householder of u vector, generate as shown in table 6 16 code book.

The channel state information feedback method using the embodiment of the present invention to provide completes the flow process of information feedback As shown in Figure 6, including:

The lateral UE of step 601, network sends transport layer pilot reference information, tests downlink channel condition for UE；

Step 602, UE receive the transport layer pilot reference information that network side issues, and carry out transport layer according to this information Channel is estimated；

Step 603, UE estimate the channel matrix obtained according to channel, determine and described transport layer from preset code book Unitary matrice, BLI and the average CQI joined；

In this step, channel, according to expression formula two, is estimated that the channel matrix H obtained carries out SVD, is obtained channel matrix by UE Right unitary matrice V=[v₁, v₂, v₃, v₄] and diagonal matrix ∑, and selection one is closest from 16 unitary matrice of described code book Unitary matrice, obtain the index PMI of this unitary matrice.

In addition it is also necessary to determine that the BLI of this UE, BLI represent that maximum singular value is absolute in the unitary matrice that PMI index is corresponding The column index of the column vector that value is corresponding.

Such as, there are 2 bit index, 00 represents v₁Being best column vector, 01 represents v₂It is best column vector, 10 represent v₃Being best column vector, 11 represent v₄Being best column vector, transport layer corresponding to best column vector is best Transport layer.

The index of multiple preferable column vector can also be indicated in BLI simultaneously, as exhausted in regulation BLI correspondence maximum singular value To value and the column index of two column vectors of second largest singular value absolute value.Such as, there are 3 bit index, 000 represents v₁, v₂Being preferable two column vectors, 001 represents v₁, v₃Being preferable two column vectors, 010 represents v₁, v₄It it is preferable two Column vector, 011 represents v₂, v₃Being preferable two column vectors, 100 represent v₂, v₄Being preferable two column vectors, 101 represent v₃, v₄It is preferable two column vectors.

In order to improve efficiency of transmission further, when the number of plies of transport layer is more, multiple transport layers can be divided into not Same set, seeks the average CQI that each is gathered, using set bigger for average CQI as channel quality best transport layer place Set, the set further according to channel quality best transport layer place builds BLI, referring specifically to table 4 and table 5.

It should be noted that the best column vector corresponding to each value of BLI is just to appoint when system initialization , i.e. eNB and UE both knows about best column vector and the corresponding transport layer that BLI value represents.

Step 604, UE send channel condition information to eNB；

After eNB receives this channel condition information, first determine whether the average CQI of each set, select the maximum collection of average CQI Close, then from this set, according to BLI, finally determine the best transport layer of channel quality.

Embodiments of the invention additionally provide a kind of UE, the structure of this terminal as it is shown in fig. 7, comprises:

Information feedback module 701, for sending channel condition information to network side, described channel condition information includes instruction The information of the best transport layer of channel quality.

Further, above-mentioned UE as shown in Figure 8, also includes:

First information generation module 702, for according to preset best transport layer fixed position, generates channel status letter Breath；

Second information transmission modular 703, for the CQI according to each transport layer, obtains CQI, and reports according to this CQI Accuse, generate channel condition information；

Calculate the average of the average CQI of different transport layer set and each transport layer and belonging transport layer set Differential CQI between CQI, generates channel condition information according to result of calculation；

3rd information transmission modular 704, is used for generating up indication signaling, and according to this up indication signaling, generates letter Channel state information；

4th information transmission modular 705, for according to up indication signaling and the average CQI of each transport layer set, generates Channel condition information.

Above-mentioned UE, can combine, at UE with a kind of channel state information feedback method that embodiments of the invention provide When network side sends channel condition information, carrying the instruction selecting best transport layer in this information, instruction network side leads to Cross described best transport layer and issue data to this UE, so, when network side determines to use MU-MIMO, it is possible to according to this channel The instruction selecting best transport layer in status information, quickly determines best transport layer, improves efficiency of transmission and biography Transmission quality, solves shortage and reports channel condition information comprehensively and effectively in the system of SU-MIMO and MU-MIMO switching at runtime Mechanism problem.

Claims (8)

1. a channel state information feedback method, is applied to single user multiple-input and multiple-output SU-MIMO and multi-user's multi input The system of multi output MU-MIMO switching at runtime, it is characterised in that including:

Under the mixed transmission modes of SU-MIMO and MU-MIMO, user terminal UE sends channel condition information to network side, institute Stating channel condition information and carry the pre-coding matrix instruction PMI for SU-MIMO, network side is according in channel condition information PMI, determines best transport layer, best for make network side can determine to use when described UE carries out MU-MIMO transmission Transport layer.

Channel state information feedback method the most according to claim 1, it is characterised in that the instruction best transport layer of channel quality Information be preset best transport layer fixed position, described UE to network side send channel condition information step before also wrap Include:

Arranging best transport layer fixed position, being specially fixing ground floor is best transport layer, or fixes first and second layer for Good transport layer.

Channel state information feedback method the most according to claim 1, it is characterised in that the instruction best transport layer of channel quality Information be channel quality indication CQI report, described CQI include the CQI of each transport layer, described UE to network side send letter Also include before the step of channel state information:

According to the CQI of each transport layer, generate CQI.

Channel state information feedback method the most according to claim 1, it is characterised in that the instruction best transport layer of channel quality The average CQI that information is different transport layer set and each transport layer and belonging transport layer set average CQI it Between differential CQI, described UE to network side send channel condition information step before also include:

Transport layer is divided at least two transport layer set；

Seek the average CQI of each transport layer set respectively；

According to the average CQI of each transport layer set, ask between the average CQI of each transport layer and belonging transport layer set Differential CQI.

Channel state information feedback method the most according to claim 1, it is characterised in that the instruction best transport layer of channel quality Information be up indication signaling, described UE to network side send channel condition information step before also include:

UE judges best transport layer, and generates up indication signaling according to judged result, and instruction network side uses this preferably to transmit Layer transmission data.

Channel state information feedback method the most according to claim 1, it is characterised in that described channel condition information includes Row indication signaling and the average CQI of each transport layer set, described UE went back before network side sends the step of channel condition information Including:

Transport layer is divided at least two transport layer set by UE；

Seek the average CQI of each transport layer set respectively；

Described UE, from transport layer set the highest for average CQI, chooses best transport layer, and generates up finger according to choosing result Show signaling.

7. a user terminal UE, is applied to single user multiple-input and multiple-output SU-MIMO and multi-user multiple-input and multiple-output MU- The system of MIMO switching at runtime, it is characterised in that under the mixed transmission modes of SU-MIMO and MU-MIMO, including:

Information feedback module, for sending channel condition information to network side, described channel condition information carries for SU- The pre-coding matrix instruction PMI of MIMO, network side according to the PMI in channel condition information, determines best transport layer, is used for making net Network side can determine the best transport layer that can use when described UE carries out MU-MIMO transmission.

UE the most according to claim 7, it is characterised in that also include:

First information generation module, for according to preset best transport layer fixed position, generates channel condition information；

Second information transmission modular, for the channel quality indicator (CQI) according to each transport layer, obtains CQI, and according to this CQI, generates channel condition information；

Calculate the average CQI of different transport layer set and each transport layer and belonging transport layer set average CQI it Between differential CQI, according to result of calculation generate channel condition information；

3rd information transmission modular, is used for generating up indication signaling, and according to this up indication signaling, generates channel status letter Breath；

4th information transmission modular, for according to up indication signaling and the average CQI of each transport layer set, generates channel status Information.