CN103220080A - Method and device for quantizing channel state information - Google Patents

Abstract

The invention discloses a method and a device for quantizing channel state information. According to the embodiment of the method and the device for quantizing the channel state information, the method that codeword indexes are provided for a base station from a user terminal is provided, the base station is provided with antennas, the number of the antennas is Nt, and the antennas are evenly arranged in a circular array. The method for quantizing the channel state information includes the following steps: according to an estimated wideband channel matrix, the user terminal determines a first codeword in a first codebook on the basis of a first predetermined rule, wherein the sequence of the first codebook is r, the first codeword is a group of beams for estimation of the wideband channel direction, and the r is equal to a positive integer from 1 to Nt; the codeword index of the first codeword is sent to the base station; for each subband, according to an estimated subband channel matrix, the user terminal determines a second codeword in a second codebook on the basis of a second predetermined rule, wherein the sequence of the second codebook is the r, the second codeword is used for describing the subband channel direction and is one wave beam in the first codeword; and then the codeword index of the second codeword is sent to the base station. Through the method and the device for quantizing the channel state information, a quite high system performance gain can be obtained at quite low PMI feedback cost.

Description

The method and apparatus that is used for the quantized channel state information

Technical field

The invention relates to a kind of method and apparatus that is used for channel condition information, especially be used for quantizing the method and apparatus of wireless communication system channel condition information about a kind of generation.

Background technology

As everyone knows, channel condition information (CSI, Channel State Information) quantizing is frequency division multiplexing (FDD, Frequency Division Duplex) key issue in the system, and uniform circular array row (UCA, uniform circular array) then be a kind ofly common be positioned at the base station, as the antenna structure of evolved node base station (eNB, evolved Node Base), especially be used for the little sub-district that focus (hotspot) covers.Be applicable to that uniform circular array is listed as the code book of configuration owing to lack, when quantizing to be used for the channel condition information of uniform circular array row, generally use the LTE Rel-10 code book that designs as linear antenna arrays originally in the industry, and this will certainly produce bigger quantization error.Therefore, need the method and apparatus that quantification is used for the channel condition information of uniform circular array row in the industry badly.

Summary of the invention

One object of the present invention is to provide a kind of method and apparatus that quantizes channel condition information in the wireless communication system, and it is applicable to the configuration of uniform circular array row, has lower feedback overhead when guaranteeing systematic function.

According to one embodiment of the invention, it provides from user terminal and provides the method for codewords indexes to the base station, and this base station configuration has N _tThe antenna of root uniform circular array row configuration.This method comprises: according to estimated broad-band channel matrix, described user terminal determines that based on first predetermined criterion order is first code word in first code book of r; Wherein this first code word is one group of wave beam that the broad-band channel direction is estimated, r=1, and 2 ... N _tThe codewords indexes of this first code word is sent to this base station; For each subband, according to estimated sub-band channel matrix, user terminal determines that based on second predetermined criterion order is second code word in second code book of r, and wherein second code word portrayal sub-band channel direction is a wave beam in first code word; The codewords indexes that reaches second code word is sent to the base station.

Accordingly, according to one embodiment of the invention, it provides a kind of base station to determine the method for code word.This method comprises: the order that receiving user terminal provides is the index of first code word of first code book of r; The order that receiving user terminal provides is the index of second code word of second code book of r; According to the index of first code word, be to determine first code word first code book of r from order; According to the index of second code word, be to determine second code word second code book of r from order; And determine final code word based on first code word and second code word.

According to one embodiment of the invention, comprise the r tabulation that the r tabulation in the code word W of this first code word and second code word is shown in the final code word W of determining and be shown:

W(：，r)＝diag(D(：，r))*W _tmp(：，r)，r＝1，2，...，N _t

W wherein _TmpFor described order is the product of first code word described in first code book of r and second code book and second code word, D is a hadamard matrix.In one embodiment, for realizing Nested property, first of hadamard matrix classifies complete 1 or complete-1 as.In another embodiment, order is the first code book C of r ₁And k first code word W ₁ ^(k)For:

$C_1=\{W_1^{\left(0\right)},W_1^{\left(1\right)},W_1^{\left(2\right)},\·\·\·,W_1^{(\frac{2(N-M)}{M}+1)}\}$

$W_1^{\left(k\right)}=\left[\begin{array}{cccc}{b}_{\frac{\mathrm{Mk}}{2}\mathrm{mod}N}& b_{(\frac{\mathrm{Mk}}{2}+1)\mathrm{mod}N}& \·\·\·& b_{(\frac{\mathrm{Mk}}{2}+M-1)\mathrm{mod}N}\end{array}\right],k=\mathrm{0,1},\·\·\·,\frac{2(N-M)}{M}+1;$

Wave beam wherein $b_{\frac{\mathrm{Mk}}{2}\mathrm{mod}N},b_{(\frac{\mathrm{Mk}}{2}+1)\mathrm{mod}N},...b_{(\frac{\mathrm{Mk}}{2}+M-1)\mathrm{mod}N}$ Be expressed as:

$b_n={[e^{-j\frac{2\mathrm{\πR}}{\mathrm{\λ}}\sin {\mathrm{\β}}_p\cos (\frac{2\mathrm{\πn}}{N}-{\mathrm{\θ}}_0),}{e}^{-j\frac{2\mathrm{\πR}}{\mathrm{\λ}}\sin {\mathrm{\β}}_p\cos (\frac{2\mathrm{\πn}}{N}-{\mathrm{\θ}}_1)},...e^{-j\frac{2\mathrm{\πR}}{\mathrm{\λ}}\sin {\mathrm{\β}}_p\cos (\frac{2\mathrm{\πn}}{N}-{\mathrm{\θ}}_{N_t-1})}]}^T,$

$n=\frac{\mathrm{Mk}}{2}\mathrm{mod}N,...(\frac{\mathrm{Mk}}{2}+M-1)\mathrm{mod}N,$ R is the radius of uniform circular array row, and λ is the electromagnetic wavelength of this base station; N is used for number to the quantification of electromagnetic horizontal azimuth α on whole phase space of this base station, α ∈ [0,2 π); β _pBe that the electromagnetic elevation angle β of this base station carries out P p value when quantizing on whole phase space, β ∈ [0, π), p=0,1 ... P-1.

In one embodiment, order is the second code book C of r ₂I second code word W ₂ ⁽ⁱ⁾For:

Wherein

Be except that i+1 element, to be 0 M*1 basis vector.

In addition, the present invention also is provided for the device of quantized channel state information.

According to one embodiment of the invention, the present invention also provides a user terminal, and it provides codewords indexes to the base station, and base station configuration has N _tThe antenna of root uniform circular array row configuration.This user terminal comprises: first code word is determined device, according to estimated broad-band channel matrix, determines that based on first predetermined criterion order is first code word in first code book of r, wherein this first code word is one group of wave beam that the broad-band channel direction is estimated, r=1,2 ... N _tThe first codewords indexes dispensing device is sent to the base station with the codewords indexes of first code word; Second code word is determined device, for each subband, according to estimated sub-band channel matrix, determines that based on second predetermined criterion order is second code word in second code book of r, and wherein second code word portrayal sub-band channel direction is a wave beam in first code word; And the second codewords indexes dispensing device, the codewords indexes of second code word is sent to the base station.

According to one embodiment of the invention, the present invention also provides a base station, disposes N _tThe antenna of root uniform circular array row configuration.This base station comprises: the first codewords indexes receiving system, receive order and be the index of first code word of first code book of r, and wherein this first code word is one group of wave beam that the broad-band channel direction is estimated, r=1,2, The second codewords indexes receiving system receives order and is the index of second code word of second code book of r, and wherein second code word portrayal sub-band channel direction is a wave beam in first code word; First code word is determined device, according to the index of first code word, is to determine described first code word first code book of r from described order; Second code word is determined device, according to the index of second code word, is to determine second code word second code book of r from order; And final code word determines device, finally determines code word based on first code word and second code word.

Compared to prior art, by in the configuration of uniform circular array row, using the method and apparatus of the quantized channel state information of this invention, it under the situation of the feedback overhead that does not increase pre-coding matrix index, greatly improves system performance gain with simple quantification manner.

Description of drawings

Fig. 1 is that user terminal provides the flow chart of codewords indexes to the base station according to an embodiment of the invention;

Fig. 2 is that the flow chart of code word is determined in the base station according to an embodiment of the invention;

Fig. 3 is the system configuration calcspar that is used for the quantized channel state information according to an embodiment of the invention.

Embodiment

Spirit for a better understanding of the present invention is described further it below in conjunction with part preferred embodiment of the present invention.

The method and apparatus that is used for the quantized channel state information of the present invention provides the code book that comprises the two-stage feedback arrangement.This code book comprises two pre-coding matrix indexes (Precoding Matrix Indicator), is respectively applied for channel performance, and the channel performance of subband and/or short-term in indication mechanism broadband.In one embodiment, the method and apparatus of this quantized channel state information is used for the configuration of uniform circular array row.Compare with LTE Rel-10 code book, it can not increase under the situation of feedback overhead of pre-coding matrix index, is showing the raising systematic function.Pre-coding matrix index and codewords indexes are same concept as understood by those skilled in the art, can be used alternatingly in the present invention.

According to one embodiment of the invention, to advance to have more at down link in (MIMO, Multiple Input Multiple Output) system more, the base station is equipped with N as eNB _tRoot antenna, and this N _tThe root antenna is the configurations of uniform circular array row.At each order r, r=0,1 ..., N _t, make up corresponding code book respectively.The code book of variant order r comprises corresponding first code book and second code book respectively, and wherein first code book comprises some first code words, and one group of wave beam (beam) that expression is estimated the broad-band channel direction is as M adjacent wave beam; And second code book comprises some second code words, and it selects a wave beam in first code word to be used for portraying the sub-band channel direction.And final code book is determined based on first code book and second code book according to certain rule.Have first code book, second code book of different orders, the final code book of determining, and last code book establishes rules really and then be stored in base station and user terminal respectively, be used for the quantized channel state information.The codewords indexes that provides the quantized channel state information by user terminal is to the base station, and the base station is determined code word and obtained channel condition information based on the codewords indexes of receiving.

As shown in Figure 1, in one embodiment of this invention, user terminal provides the codewords indexes of quantized channel state information to the base station.In step 100, user terminal is according to estimated broad-band channel matrix, and based on a predetermined criterion, maximum capacity criterion or distance minimization criterion etc. determine that order is the first code book C of r as understood by those skilled in the art ₁In first code word, wherein this first code word is one group of wave beam that the broad-band channel direction is estimated, r=1,2 ... N _t

In step 101, the codewords indexes of first code word that user terminal will be determined is sent to the base station.

And for each subband, in step 102, user terminal is then according to estimated sub-band channel matrix, also determine that based on a predetermined criterion (this predetermined criterion can be identical or different with the predetermined criterion of determining first code word) order is second code word in second code book of r, this second code word portrayal sub-band channel direction is a wave beam in first code word.

In step 103, user terminal also is sent to the base station with the codewords indexes of second code word.

Accordingly, in base station side, as shown in Figure 2, receive order in step 200 base station and be the index of first code word of first code book of r.

Receive the index of second code word that order is second code book of r in step 201.

In step 202 and according to the index of first code word, from being first code book of r, order determines this first code word.

At the index of step 203, be to determine this second code word second code book of r from order according to second code word.

For obtaining final channel condition information, determine final code word based on first code word and second code word in step 204 base station.

According to one embodiment of the invention, when the quantized channel state information, the feedback cycle of first code word that expression broad-band channel direction is estimated will be longer than or to the feedback cycle of second code word of portrayal sub-band channel direction.In other words, the cycle of base station is longer than or is equaled the codewords indexes of second code word is sent to the cycle that the codewords indexes of first code word is sent to the base station.The base station can use previous first code word and new second code word of determining to determine final code word under the index situation of not receiving the first new code word.When the index of first code word did not comprise the order information of its corresponding code book with the index of second code word, user terminal also need send this order information to the base station.

In addition, when the index of the index of determining first code word and second code word, user terminal can use different definite modes, as determining the index of first code word, the index of second code word simultaneously; Or the index of earlier definite first code word, the index of definite second code word again.

Accordingly, each step in the foregoing description does not limit its actual operating sequence with the order of writing, and should not limit technical scheme of the present invention with this.

Below further set forth according to one embodiment of the invention, how channel condition information is quantized, promptly produce the code book that is used for the above-mentioned two-stage feedback arrangement of having of quantized channel state information.

According to one embodiment of the invention, to advance to have more at down link in (MIMO, Multiple Input Multiple Output) system more, the base station is equipped with N _tRoot antenna, and this N _tThe root antenna is the configurations of uniform circular array row, and wherein the azimuth of n root antenna is θ _nSince the uniform distribution on same circumference of each antenna, θ _nCan be expressed as:

${\mathrm{\θ}}_n=\frac{2\mathrm{\π}}{N_t}n,n=\mathrm{0,1},\·\·\·N_t-1$

The electromagnetic angle of departure (AoD, Angle of Departure) of this base station is expressed as (α, β), wherein α and β are respectively the electromagnetic horizontal azimuth and the elevation angle of this base station.Then base station to the principal character vector of the channel matrix between the user terminal has following form:

$v={[e^{-j\frac{2\mathrm{\πR}}{\mathrm{\λ}}\sin \mathrm{\β}\cos (\mathrm{\α}-{\mathrm{\θ}}_0)},e^{-j\frac{2\mathrm{\πR}}{\mathrm{\λ}}\sin \mathrm{\β}\cos (\mathrm{\α}-{\mathrm{\θ}}_1)},\·\·\·,e^{-j\frac{2\mathrm{\πR}}{\mathrm{\λ}}\sin \mathrm{\β}\cos (\mathrm{\α}-{\mathrm{\θ}}_{N_{t-1}})}]}^T---\left(1\right)$

Wherein α ∈ [0,2 π), [0, π), R is the radius of uniform circular array row to β ∈, and λ is the electromagnetic wavelength of base station.

In the present embodiment, make up the code book with two-stage feedback arrangement of the present invention based on this channel matrix.At each order r r=0,1 ..., N _t, making up corresponding code book, the code book of variant order r comprises the corresponding first code book C ₁With the second code book C ₂The first code book C wherein ₁Comprise some first code word W ₁, one group of wave beam (beam) that expression is estimated the broad-band channel direction is as M adjacent wave beam; And the second code book C ₂Comprise some second code word W ₂, it selects first code word W ₁In a wave beam be used for portraying the sub-band channel direction.

Can with α and β on whole phase space respectively uniform quantization be N and P value (also can not carry out uniform quantization in other embodiments), that is:

$\mathrm{\α}=\frac{2\mathrm{\πn}}{N},n=\mathrm{0,1},\·\·\·,N-1;$

${\mathrm{\β}}_p=\frac{\mathrm{\πp}}{P},p=\mathrm{0,1},...,P-1;$

At β _p(β is carried out P p value when quantizing on whole phase space) when determining, then the first code book C ₁In first code word W ₁In wave beam be expressed as

$b_n={[e^{-j\frac{2\mathrm{\πR}}{\mathrm{\λ}}\sin {\mathrm{\β}}_p\cos (\frac{2\mathrm{\πn}}{N}-{\mathrm{\θ}}_0),}{e}^{-j\frac{2\mathrm{\πR}}{\mathrm{\λ}}\sin {\mathrm{\β}}_p\cos (\frac{2\mathrm{\πn}}{N}-{\mathrm{\θ}}_1)},...e^{-j\frac{2\mathrm{\πR}}{\mathrm{\λ}}\sin {\mathrm{\β}}_p\cos (\frac{2\mathrm{\πn}}{N}-{\mathrm{\θ}}_{N_t-1})}]}^T---\left(2\right)$

Usually consider that for simplifying elevation angle β is made as

Therefore equation (2) becomes:

$b_n={[e^{-j\frac{2\mathrm{\πR}}{\mathrm{\λ}}\cos (\frac{2\mathrm{\πn}}{N}-{\mathrm{\θ}}_0)},e^{-j\frac{2\mathrm{\πR}}{\mathrm{\λ}}\cos (\frac{2\mathrm{\πn}}{N}-{\mathrm{\θ}}_1)},\·\·\·,e^{-j\frac{2\mathrm{\πR}}{\mathrm{\λ}}\cos (\frac{2\mathrm{\πn}}{N}-{\mathrm{\θ}}_{N_t-1})}]}^T,n=\mathrm{0,1},\·\·\·,N-1---\left(3\right)$

When first code word W ₁When comprising M adjacent beams, the first code book C then ₁In k first code word W ₁Be expressed as:

$W_1^{\left(k\right)}=\left[\begin{array}{cccc}{b}_{\frac{\mathrm{Mk}}{2}\mathrm{mod}N}& b_{(\frac{\mathrm{Mk}}{2}+1)\mathrm{mod}N}& \·\·\·& b_{(\frac{\mathrm{Mk}}{2}+M-1)\mathrm{mod}N}\end{array}\right],k=\mathrm{0,1},\·\·\·,\frac{2(N-M)}{M}+1---\left(4\right)$

K represents first code word W in the present embodiment ₁Index, and store after encoded according to need and transmit.

First code word W ₁The first code book C ₁Be

$C_1=\{W_1^{\left(0\right)},W_1^{\left(1\right)},W_1^{\left(2\right)},\·\·\·,W_1^{(\frac{2(N-M)}{M}+1)}\}---\left(5\right)$

Set order in the present embodiment and be 1 to N _tThe first code book C ₁All identical.In other implementation column, can obtain the first different code books with the M value by setting different N at different orders.

Second code word W ₂It is first code word W of selecting to have corresponding order ₁In a wave beam, i.e. one in the equation (4) row.Therefore, order is 1 the second code book C ₂In i second code word W ₂Be

$W_2^{\left(i\right)}=\frac{1}{\sqrt{N_i}}\left[{\tilde{e}}_i\right],i=\mathrm{0,1},\·\·\·,M-1---\left(6\right)$

Wherein

Be except that i+1 element, to be 0 M*1 basis vector.Accordingly, this order is 1 the second code book C ₂Be expressed as:

C ₂＝{W ₂ ⁽⁰⁾，W ₂ ⁽¹⁾，…，W ₂ ^(M-1))} (7)

For the second code book C with higher order r ₂, its i second code word W then ₂ ⁽ⁱ⁾Be expressed as:

I represents second code word W in the present embodiment ₂Index, and store after encoded according to need and transmit.

Last code word W is based on first code word W ₁With second code word W ₂Determine.As for making up normalized code book, use Hadamard (Hadamard) matrix to carry out linear transformation and define W _Tmp=W ₁W ₂, the r tabulation of then last code word W is shown:

W(：，r)＝diag(D(：，r))*W _tmp(：，r)， r＝1，2，...，N _t (9)

Wherein D is a hadamard matrix, for example:

$D=\left[\begin{array}{cccccccc}1& 1& 1& 1& 1& 1& 1& 1\\ 1& 1& -1& 1& -1& -1& -1& 1\\ 1& -1& -1& -1& 1& 1& -1& 1\\ 1& -1& 1& -1& -1& -1& 1& 1\\ 1& 1& 1& -1& -1& 1& -1& -1\\ 1& 1& -1& -1& 1& -1& 1& -1\\ 1& -1& -1& 1& -1& 1& 1& -1\\ 1& -1& 1& 1& 1& -1& -1& -1\end{array}\right]$

With order is that 1 final code book is an example, and its code word W is W ₁With W ₂Multiply each other, promptly

W＝W ₁W ₂ (10)

In addition, have Nested property, can select for use first to classify complete 1 or complete-1 hadamard matrix as for making final code book.

Have first code book, second code book of different orders, the final code book of determining, and last code book establishes rules really and then be stored in base station and user terminal respectively, be used for the quantized channel state information.

The present invention uses two-stage codebook quantized channel state information, and it is the feedback overhead of balance system performance and pre-coding matrix index effectively.Concrete, the required bit number of its first code word is

The required bit number of second code word is log ₂(M), M is the numbers of beams in first code word; The bit number that needs altogether is

The bandwidth of supposing system is divided into B subband, feedback code on each subband, and then for the code book of one-level feedback arrangement, its code book expense minimum is Blog ₂(N) bit, wherein N is the codebook size in the code book of one-level feedback arrangement.Obviously, under the identical situation of N, the present invention uses the feedback overhead of the method for two-stage codebook quantized channel state information than this saving of one-level code code word, and in the performance performance, the present invention is not inferior yet simultaneously.

Exemplary, for the uniform circular array row configuration of 8 antennas of antenna distance with 0.5 wavelength, i.e. R=0.25/sin (π/8).Suppose N=64, M=8, the then first code book C ₁Size be 4 bits, and the second code book C ₂Size be 3 bits.Below listed the first code book C in detail ₁With the second code book C ₂Design:

The first code book C of 4 bits ₁And first code word W ₁:

$b_n={[e^{-j\frac{2\mathrm{\πR}}{\mathrm{\λ}}\cos (\frac{2\mathrm{\πn}}{64}-{\mathrm{\θ}}_0)},e^{-j\frac{2\mathrm{\πR}}{\mathrm{\λ}}\cos (\frac{2\mathrm{\πn}}{64}-{\mathrm{\θ}}_1)},\·\·\·,e^{-j\frac{2\mathrm{\πR}}{\mathrm{\λ}}\cos (\frac{2\mathrm{\πn}}{64}-{\mathrm{\θ}}_{N_t-1})}]}^T,n=\mathrm{0,1},\·\·\·,63$

W ₁ ^(k)∈{[b _4kmod64 b _(4k+1)mod64 … b _(4k+7)mod64]：k＝0，1，…，15}

C ₁＝{W ₁ ⁽⁰⁾，W ₁ ⁽¹⁾，W ₁ ⁽²⁾，…，W ₁ ⁽¹⁵⁾}

The second code book C of 3 bits ₂Second code word W ₂:

Based on W ₁And W ₂Last code book be

W(：，r)＝diag(D(：，r))*W _tmp(：，r)， r＝1，2，...，N _t N _t＝8

W wherein _Tmp=W ₁W ₂

$D=\left[\begin{array}{cccccccc}1& 1& 1& 1& 1& 1& 1& 1\\ 1& 1& -1& 1& -1& -1& -1& 1\\ 1& -1& -1& -1& 1& 1& -1& 1\\ 1& -1& 1& -1& -1& -1& 1& 1\\ 1& 1& 1& -1& -1& 1& -1& -1\\ 1& 1& -1& -1& 1& -1& 1& -1\\ 1& -1& -1& 1& -1& 1& 1& -1\\ 1& -1& 1& 1& 1& -1& -1& -1\end{array}\right]$

The present invention also is provided for the device of quantized channel state information, and its use has the code book of two-stage back locking structure.

Fig. 3 example the system block diagram of the device of quantized channel state information according to an embodiment of the invention, in this system, user terminal 30 provides codewords indexes to base station 40, this base station 40 disposes N _tThe antenna of root uniform circular array row configuration.User terminal 30 comprises: first code word is determined device 300, and it is according to estimated broad-band channel matrix, determines that based on first predetermined criterion order is first code word in first code book of r, wherein this first code word is one group of wave beam that the broad-band channel direction is estimated, r=1,2, The first codewords indexes dispensing device 301, its codewords indexes with first code word is sent to the base station; Second code word is determined device 302, it is for each subband, according to estimated sub-band channel matrix, determines that based on second predetermined criterion order is second code word in second code book of r, wherein second code word is portrayed the sub-band channel direction, and it is a wave beam in first code word; And the second codewords indexes dispensing device 303, the codewords indexes of second code word is sent to the base station.

Accordingly, base station 40 comprises: the first codewords indexes receiving system 400, the order that it receives user terminal 30 provides are the index of first code word of first code book of r; The second codewords indexes receiving system 401, the order that receiving user terminal 30 provides are the index of second code word of second code book of r; First code word is determined device 402, and it is according to the index of first code word, determines first code word from order is first code book of r; Second code word is determined device 403, according to the index of second code word, is to determine second code word second code book of r from order; And final code word determines device 404, finally determines code word based on first code word and second code word.

Below, further highlight advantage of the present invention by emulation on the system layer performance.This emulation in having the FFD system of 19 hexagonal cellular downlink, used respectively an one-level code book that is used for the uniform circular array row, LTE Rel-10 code book, with the code book with two-stage feedback arrangement of the present invention.Table 1 has provided concrete simulation parameter and modeling is set.Simulation parameter and modeling based on table 1 are set, and table 2,3,4 has provided respectively bandwidth being allocated to B, during B=10, respectively is used for the systematic function that different code book showed and the feedback overhead of quantized channel state information.Obviously,, can have significant systematic function to promote compared to LTE Rel-10 code book according to the code book with two-stage feedback arrangement of the present invention, and compare with the one-level code book can be very low feedback overhead obtain similar systematic function.

Table 1 simulation parameter and modeling are set

Table 2 is used for the PMI feedback overhead (B=10) of SU-MIMO

The SU-MIMO performance of 8 antennas of table 3 uniform circular array row configuration

The SU/MU-MIMO performance of 8 antennas of table 4 uniform circular array row configuration

Technology contents of the present invention and technical characterstic disclose as above, yet those of ordinary skill in the art still may be based on teaching of the present invention and announcements and done all replacement and modifications that does not deviate from spirit of the present invention.Therefore, protection scope of the present invention should be not limited to the content that embodiment discloses, and should comprise various do not deviate from replacement of the present invention and modifications, and is contained by present patent application claims.

Claims (19)

1. method, it provides codewords indexes from user terminal to the base station, and described base station configuration has N _tThe antenna of root uniform circular array row configuration comprises:

According to estimated broad-band channel matrix, described user terminal determines that based on first predetermined criterion order is first code word in first code book of r, and wherein this first code word is one group of wave beam that the broad-band channel direction is estimated, r=1, and 2 ... N _t

The codewords indexes of described first code word is sent to described base station;

For each subband, according to estimated sub-band channel matrix, described user terminal determines that based on second predetermined criterion order is second code word in second code book of r, and wherein said second code word portrayal sub-band channel direction is a wave beam in described first code word; And

The codewords indexes of described second code word is sent to described base station.

2. the method for claim 1, the r tabulation that wherein comprises in the code word W of this first code word and second code word is shown:

W(：，r)＝diag(D(：，r))*W _tmp(：，r)，r＝1，2，...，N _t

W wherein _TmpFor described order is the product of first code word described in first code book of r and second code book and second code word, D is a hadamard matrix.

3. method as claimed in claim 1 or 2, wherein said order are the first code book C of r ₁And k first code word W ₁ ^(k)For:

$C_1=\{W_1^{\left(0\right)},W_1^{\left(1\right)},W_1^{\left(2\right)},\·\·\·,W_1^{(\frac{2(N-M)}{M}+1)}\}$

$W_1^{\left(k\right)}=\left[\begin{array}{cccc}{b}_{\frac{\mathrm{Mk}}{2}\mathrm{mod}N}& b_{(\frac{\mathrm{Mk}}{2}+1)\mathrm{mod}N}& \·\·\·& b_{(\frac{\mathrm{Mk}}{2}+M-1)\mathrm{mod}N}\end{array}\right],k=\mathrm{0,1},\·\·\·,\frac{2(N-M)}{M}+1;$

Wherein said wave beam $b_{\frac{\mathrm{Mk}}{2}\mathrm{mod}N},b_{(\frac{\mathrm{Mk}}{2}+1)\mathrm{mod}N},...b_{(\frac{\mathrm{Mk}}{2}+M-1)\mathrm{mod}N}$ Be expressed as

$b_n={[e^{-j\frac{2\mathrm{\πR}}{\mathrm{\λ}}\sin {\mathrm{\β}}_p\cos (\frac{2\mathrm{\πn}}{N}-{\mathrm{\θ}}_0),}{e}^{-j\frac{2\mathrm{\πR}}{\mathrm{\λ}}\sin {\mathrm{\β}}_p\cos (\frac{2\mathrm{\πn}}{N}-{\mathrm{\θ}}_1)},...e^{-j\frac{2\mathrm{\πR}}{\mathrm{\λ}}\sin {\mathrm{\β}}_p\cos (\frac{2\mathrm{\πn}}{N}-{\mathrm{\θ}}_{N_t-1})}]}^T,$

$n=\frac{\mathrm{Mk}}{2}\mathrm{mod}N,...(\frac{\mathrm{Mk}}{2}+M-1)\mathrm{mod}N,$ R is the radius of uniform circular array row, and λ is the electromagnetic wavelength of this base station; N is used for number to the quantification of electromagnetic horizontal azimuth α on whole phase space of this base station, α ∈ [0,2 π); M is the quantity of the wave beam in described first code word; β _pBe that the electromagnetic elevation angle β of this base station carries out P p value when quantizing on whole phase space, β ∈ [0, π), p=0,1 ... P-1.

4. method as claimed in claim 3, wherein said order are the second code book C of r ₂I second code word W ₂ ⁽ⁱ⁾For:

Wherein Be except that i+1 element, to be 0 M*1 basis vector.

5. the method for claim 1, the cycle of described base station is longer than or is equaled the codewords indexes of described second code word is sent to the cycle that wherein codewords indexes of described first code word is sent to described base station.

6. method as claimed in claim 2, first of wherein said hadamard matrix classify complete 1 or complete-1 as.

7. the method for code word is determined in a base station, and described code word has the two-stage feedback arrangement, and described base station configuration has N _tThe antenna of root uniform circular array row configuration comprises:

Receive order and be the index of first code word of first code book of r, wherein this first code word is one group of wave beam that the broad-band channel direction is estimated, r=1, and 2 ... N _t

Receive order and be the index of second code word of second code book of r, wherein said second code word portrayal sub-band channel direction is a wave beam in described first code word;

According to the index of described first code word, be to determine described first code word first code book of r from described order;

According to the index of described second code word, be to determine described second code word second code book of r from described order; And

Finally determine described code word based on described first code word and second code word.

8. method as claimed in claim 7, the r tabulation in the wherein said final code word W of determining is shown:

W(：，r)＝diag(D(：，r))*W _tmp(：，r)，r＝1，2，...，N _t

W wherein _TmpFor described order is the product of first code word described in first code book of r and second code book and second code word, D is a hadamard matrix.

9. as claim 7 or 8 described methods, wherein said order is the first code book C of r ₁And k first code word W ₁ ^(k)For

$C_1=\{W_1^{\left(0\right)},W_1^{\left(1\right)},W_1^{\left(2\right)},\·\·\·,W_1^{(\frac{2(N-M)}{M}+1)}\}$

$W_1^{\left(k\right)}=\left[\begin{array}{cccc}{b}_{\frac{\mathrm{Mk}}{2}\mathrm{mod}N}& b_{(\frac{\mathrm{Mk}}{2}+1)\mathrm{mod}N}& \·\·\·& b_{(\frac{\mathrm{Mk}}{2}+M-1)\mathrm{mod}N}\end{array}\right],k=\mathrm{0,1},\·\·\·,\frac{2(N-M)}{M}+1;$

Wherein said wave beam $b_{\frac{\mathrm{Mk}}{2}\mathrm{mod}N},b_{(\frac{\mathrm{Mk}}{2}+1)\mathrm{mod}N},...b_{(\frac{\mathrm{Mk}}{2}+M-1)\mathrm{mod}N}$ Be expressed as

$b_n={[e^{-j\frac{2\mathrm{\πR}}{\mathrm{\λ}}\sin {\mathrm{\β}}_p\cos (\frac{2\mathrm{\πn}}{N}-{\mathrm{\θ}}_0),}{e}^{-j\frac{2\mathrm{\πR}}{\mathrm{\λ}}\sin {\mathrm{\β}}_p\cos (\frac{2\mathrm{\πn}}{N}-{\mathrm{\θ}}_1)},...e^{-j\frac{2\mathrm{\πR}}{\mathrm{\λ}}\sin {\mathrm{\β}}_p\cos (\frac{2\mathrm{\πn}}{N}-{\mathrm{\θ}}_{N_t-1})}]}^T,$

$n=\frac{\mathrm{Mk}}{2}\mathrm{mod}N,...(\frac{\mathrm{Mk}}{2}+M-1)\mathrm{mod}N,$ R is the radius of uniform circular array row, and λ is the electromagnetic wavelength of this base station; N is used for number to the quantification of electromagnetic horizontal azimuth α on whole phase space of this base station, α ∈ [0,2 π); β _pBe that the electromagnetic elevation angle β of this base station carries out P p value when quantizing on whole phase space, β ∈ [0, π), p=0,1 ... P-1.

10. method as claimed in claim 9, wherein said order are the second code book C of r ₂I second code word W ₂ ⁽ⁱ⁾For:

Wherein

Be except that i+1 element, to be 0 M*1 basis vector.

11. method as claimed in claim 8, first of wherein said hadamard matrix classify complete 1 or complete-1 as.

12. a user terminal, it provides codewords indexes to the base station, and described base station configuration has N _tThe antenna of root uniform circular array row configuration, described user terminal comprises:

First code word is determined device, according to estimated broad-band channel matrix, determines that based on first predetermined criterion order is first code word in first code book of r, and wherein this first code word is one group of wave beam that the broad-band channel direction is estimated, r=1, and 2 ... N _t

The first codewords indexes dispensing device is sent to described base station with the codewords indexes of described first code word;

Second code word is determined device, for each subband,, determine that based on second predetermined criterion order is second code word in second code book of r according to estimated sub-band channel matrix, wherein said second code word portrayal sub-band channel direction is a wave beam in described first code word; And

The second codewords indexes dispensing device is sent to described base station with the codewords indexes of described second code word.

13. user terminal as claimed in claim 12, the r tabulation that wherein comprises in the code word W of this first code word and second code word is shown:

W(：，r)＝diag(D(：，r))*W _tmp(：，r)， r＝1，2，...，N _t

W wherein _TmpFor described order is the product of first code word described in first code book of r and second code book and second code word, D is a hadamard matrix.

14. as claim 12 or 13 described user terminals, wherein said order is the first code book C of r ₁And k first code word W ₁ ^(k)For:

$C_1=\{W_1^{\left(0\right)},W_1^{\left(1\right)},W_1^{\left(2\right)},\·\·\·,W_1^{(\frac{2(N-M)}{M}+1)}\};$

$W_1^{\left(k\right)}=\left[\begin{array}{cccc}{b}_{\frac{\mathrm{Mk}}{2}\mathrm{mod}N}& b_{(\frac{\mathrm{Mk}}{2}+1)\mathrm{mod}N}& \·\·\·& b_{(\frac{\mathrm{Mk}}{2}+M-1)\mathrm{mod}N}\end{array}\right],k=\mathrm{0,1},\·\·\·,\frac{2(N-M)}{M}+1;$

Wherein said wave beam $b_{\frac{\mathrm{Mk}}{2}\mathrm{mod}N},b_{(\frac{\mathrm{Mk}}{2}+1)\mathrm{mod}N},...b_{(\frac{\mathrm{Mk}}{2}+M-1)\mathrm{mod}N}$ Be expressed as

$b_n={[e^{-j\frac{2\mathrm{\πR}}{\mathrm{\λ}}\sin {\mathrm{\β}}_p\cos (\frac{2\mathrm{\πn}}{N}-{\mathrm{\θ}}_0),}{e}^{-j\frac{2\mathrm{\πR}}{\mathrm{\λ}}\sin {\mathrm{\β}}_p\cos (\frac{2\mathrm{\πn}}{N}-{\mathrm{\θ}}_1)},...e^{-j\frac{2\mathrm{\πR}}{\mathrm{\λ}}\sin {\mathrm{\β}}_p\cos (\frac{2\mathrm{\πn}}{N}-{\mathrm{\θ}}_{N_t-1})}]}^T,$

$n=\frac{\mathrm{Mk}}{2}\mathrm{mod}N,...(\frac{\mathrm{Mk}}{2}+M-1)\mathrm{mod}N,$ R is the radius of uniform circular array row, and λ is the electromagnetic wavelength of this base station; N is used for number to the quantification of electromagnetic horizontal azimuth α on whole phase space of this base station, α ∈ [0,2 π); M is the quantity of the wave beam in described first code word; β _pBe that the electromagnetic elevation angle β of this base station carries out P p value when quantizing on whole phase space, β ∈ [0, π), p=0,1 ... P-1.

15. user terminal as claimed in claim 14, wherein said order are the second code book C of r ₂I second code word W ₂ ⁽ⁱ⁾For:

Wherein

Be except that i+1 element, to be 0 M*1 basis vector.

16. a base station disposes N _tThe antenna of root uniform circular array row configuration, it comprises:

The first codewords indexes receiving system receives order and is the index of first code word of first code book of r, and wherein this first code word is one group of wave beam that the broad-band channel direction is estimated, r=1, and 2 ... N _t

The second codewords indexes receiving system receives order and is the index of second code word of second code book of r, and wherein said second code word portrayal sub-band channel direction is a wave beam in described first code word;

First code word is determined device, according to the index of described first code word, is to determine described first code word first code book of r from described order;

Second code word is determined device, according to the index of described second code word, is to determine described second code word second code book of r from described order; And

Final code word is determined device, finally determines code word based on described first code word and second code word.

17. base station as claimed in claim 16, the r tabulation in the wherein said final code word W of determining is shown:

W(：，r)＝diag(D(：，r))*W _tmp(：，r)， r＝1，2，...，N _t

W wherein _TmpFor described order is the product of first code word described in first code book of r and second code book and second code word, D is a hadamard matrix.

18. as claim 16 or 17 described base stations, wherein said order is the first code book C of r ₁And k first code word W ₁ ^(k)For:

$C_1=\{W_1^{\left(0\right)},W_1^{\left(1\right)},W_1^{\left(2\right)},\·\·\·,W_1^{(\frac{2(N-M)}{M}+1)}\};$

$W_1^{\left(k\right)}=\left[\begin{array}{cccc}{b}_{\frac{\mathrm{Mk}}{2}\mathrm{mod}N}& b_{(\frac{\mathrm{Mk}}{2}+1)\mathrm{mod}N}& \·\·\·& b_{(\frac{\mathrm{Mk}}{2}+M-1)\mathrm{mod}N}\end{array}\right],$ $k=\mathrm{0,1},\·\·\·,\frac{2(N-M)}{M}+1;$

Wherein said wave beam $b_{\frac{\mathrm{Mk}}{2}\mathrm{mod}N},b_{(\frac{\mathrm{Mk}}{2}+1)\mathrm{mod}N},...b_{(\frac{\mathrm{Mk}}{2}+M-1)\mathrm{mod}N}$ Be expressed as

$b_n={[e^{-j\frac{2\mathrm{\πR}}{\mathrm{\λ}}\sin {\mathrm{\β}}_p\cos (\frac{2\mathrm{\πn}}{N}-{\mathrm{\θ}}_0),}{e}^{-j\frac{2\mathrm{\πR}}{\mathrm{\λ}}\sin {\mathrm{\β}}_p\cos (\frac{2\mathrm{\πn}}{N}-{\mathrm{\θ}}_1)},...e^{-j\frac{2\mathrm{\πR}}{\mathrm{\λ}}\sin {\mathrm{\β}}_p\cos (\frac{2\mathrm{\πn}}{N}-{\mathrm{\θ}}_{N_t-1})}]}^T,$

$n=\frac{\mathrm{Mk}}{2}\mathrm{mod}N,...(\frac{\mathrm{Mk}}{2}+M-1)\mathrm{mod}N,$ R is the radius of uniform circular array row, and λ is the electromagnetic wavelength of this base station; N is used for number to the quantification of electromagnetic horizontal azimuth α on whole phase space of this base station, α ∈ [0,2 π); β _pBe that the electromagnetic elevation angle β of this base station carries out P p value when quantizing on whole phase space, β ∈ [0, π), p=0,1 ... P-1.

19. base station as claimed in claim 18, wherein said order are i second code word W of the second code book C2 of r ₂ ⁽ⁱ⁾For:

Wherein Be except that i+1 element, to be 0 M*1 basis vector.

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