CN101686073B - Pre-coding power normalization parameter transmitting and receiving method and equipment - Google Patents

Abstract

The invention discloses a pre-coding power normalization parameter transmitting and receiving method, comprising the following steps: a base station receives an ascending signal transmitted by a terminal, and channel information between multiple antennas of the base station and the terminal is obtained according to the ascending signal; the base station adopts a pre-coding algorithm to calculate a pre-coding matrix corresponding to a descending time-frequency resource, and the transmitting powder normalization parameter of the time-frequency resource is calculated by utilizing the pre-coding matrix; the base station leads the transmitting powder normalization parameter to be bore in a descending signal and to be transmitted to the terminal. The invention further discloses a pre-coding power normalization parameter transmitting and receiving method and equipment; by adopting the technical proposal provided by the invention, the pre-coding power normalization parameter is transmitted to a receiving terminal, and the problem of MIMO pre-coding power normalization parameter transmission of multiple users is solved; in addition, the method is simple and has high efficiency, so as to be beneficial to further promoting the system performance.

Description

The sending, receiving method of pre-coding power normalization parameter and equipment

Technical field

The present invention relates to moving communicating field, particularly, the present invention relates to mobile communication multi-antenna technology field.

Background technology

The multi-antenna technology of physical layer has become one of key technology of Next-Generation Wireless Communication Systems, multi-antenna technology has lot of advantages, such as utilizing the spatial multiplexing gain of many antennas to expand the throughput of system, utilize the diversity gain of many antennas to improve systematic function, utilize the directive gain of antenna to distinguish receiving terminal and eliminate interference between receiving terminal etc.

In the downlink broadcast channel of the point-to-multipoint of modern cellular mobile communication, due to the difference of each receiving terminal on geographical position, can not work in coordination with reception, when the reception signal between each receiving terminal exists phase mutual interference, can not adopt the method for Multiuser Detection to avoid interference.Therefore the effective ways that solve radio multi-user MIMO (Multiple-Input Multiple-Output, multiple-input, multiple-output) broadcast channel multi-user interference problem normally adopt precoding technique.Theory analysis proof adopts the method for precoding such as DPC (Dirty Paper Coding) can reach the capacity of MIMO Gauss broadcast channel, therefore the precoding technique research to radio multi-user MIMO broadcast channel, is to solve the key issue that MIMO technology is applied to cellular system of new generation or WLAN (wireless local area network).

Yet owing to signal having been carried out to precoding processing to sending, base station side may have greatly changed to the transmitting power on each antenna, especially when channel relevancy is larger.For transmitting power scope is controlled, base station side needs power to be normalized after transmitting terminal precoding, and receiving terminal need to be known power normalization parameter, could correct demodulating data.Therefore to effective sending and receiving of pre-coding power normalization parameter, be, that MIMO technology is applied to the problem that cellular system of new generation or WLAN (wireless local area network) will face.

Summary of the invention

The sending, receiving method and the equipment that the object of the present invention is to provide a kind of pre-coding power normalization parameter, be transferred to receiving terminal to realize by pre-coding power normalization parameter, solves the problem of transmission of multi-user MIMO pre-encoding power normalization parameter.

In order to achieve the above object, embodiments of the invention disclose a kind of sending method of pre-coding power normalization parameter, comprise the following steps:

The upward signal that base station receiving terminal sends, obtains the channel information between the many antennas in described base station and described terminal according to described upward signal;

Described base station adopts precoding algorithm to calculate pre-coding matrix corresponding to down time-frequency resource, utilizes described pre-coding matrix to calculate the transmitting power normalized parameter of described running time-frequency resource;

Described base station is carried on described transmitting power normalized parameter in downstream signal, to send to described terminal.

According to embodiments of the invention, the channel information obtaining between the many antennas in described base station and described terminal according to described upward signal comprises:

The ascending pilot frequency that described base station sends according to described terminal, estimates up channel information between the many antennas in described base station and described terminal;

By interpolation algorithm, described base station obtains the channel information on up all running time-frequency resources;

According to the characteristic of channel of tdd systems, described base station obtains the channel information on descending all running time-frequency resources according to the channel information on up all running time-frequency resources.

According to embodiments of the invention, after base station obtains the channel information between the many antennas in described base station and described terminal according to described upward signal, described base station is selected N user and is carried out multiuser MIMO transmission from multi-user, wherein N is for being greater than 1, the integer that is less than or equal to antenna for base station number, comprises the following steps:

The best user of described base station selected channel quality is as primary user;

Described base station, from remaining user, selects a user and described primary user to form one group, and channel capacity is maximized;

Increase progressively successively user, make to increase the user and the described primary user that come in and form one group, and channel capacity is maximized, until number of users reaches N.

According to embodiments of the invention, described precoding algorithm comprises: zero forcing algorithm, least-mean-square error algorithm, block diagonalization (Block Diagonalization) algorithm, THP (Tomlinson-Harashima) algorithm, auxiliary (LR) algorithm of Ge Yuejian or Ge Yuejian auxiliary vector precoding (LRVP) algorithm.

According to embodiments of the invention, described downstream signal comprises down-bound pilot frequency signal.

According to embodiments of the invention, described downstream signal is ofdm modulation signal, and described transmitting power normalized parameter is carried in described pilot tone.

According to embodiments of the invention, described pilot resources is carried out to precoding processing.

According to embodiments of the invention, described downstream signal comprises business datum signal, and the modulation system of described business datum is constant amplitude phase-modulation.

According to embodiments of the invention, described downstream signal is ofdm modulation signal, and described transmitting power normalized parameter is carried on described business datum signal time-frequency domain.

According to embodiments of the invention, described business datum signal time-frequency domain resources is carried out to precoding processing.

According to embodiments of the invention, when described precoding algorithm is linear predictive coding algorithm, described base station is carried on described transmitting power normalized parameter corresponding to described running time-frequency resource in downstream signal, to send to described terminal; When described precoding algorithm is nonlinear precoding algorithm, described base station is carried on the average of described transmitting power normalized parameter corresponding to described running time-frequency resource in downstream signal, to send to described terminal.

The present invention also provides a kind of method of reseptance of pre-coding power normalization parameter, comprises the following steps: terminal receives the downstream signal that base station sends, and described downstream signal carries transmitting power normalized parameter information; Described terminal is determined the mode of system bearing transmitting power normalized parameter, by described downstream signal, obtains described transmitting power normalized parameter.

According to embodiments of the invention, described downstream signal comprises down-bound pilot frequency signal, and when described transmitting power normalized parameter is carried in described down-bound pilot frequency signal, described terminal is carried out demodulation to the signal of pilot frequency locations, and restituted signal is power normalization parameter.

According to embodiments of the invention, described downstream signal comprises business datum signal, and the modulation system of described business datum is constant amplitude phase-modulation, the signal demodulation of described terminal to business time-frequency position, the amplitude divided by modulation constellation after delivery is power normalization parameter.

The present invention also provides a kind of base station equipment, comprising:

Receiver module, the upward signal that described receiver module sends for receiving terminal; Precoding module, described precoding module, for according to the upward signal of described receiver module reception, is determined the transmitting power normalized parameter of the downstream signal that described base station equipment sends; Sending module, described sending module sends to described terminal for described transmitting power normalized parameter is carried on to downstream signal.

According to embodiments of the invention, described precoding module comprises: channel estimation module, and described channel estimation module, for according to described upward signal, obtains estimating descending channel information between the many antennas of described base station equipment and described terminal; Computing module, described computing module adopts precoding algorithm to calculate pre-coding matrix corresponding to down time-frequency resource, utilizes described pre-coding matrix to calculate the transmitting power normalized parameter of described running time-frequency resource; Mapping block, described mapping block is carried on described transmitting power normalized parameter on described downstream signal running time-frequency resource, by downstream signal, sends to described terminal.

According to embodiments of the invention, the described downstream signal of described mapping block carrying comprises down-bound pilot frequency signal.

According to embodiments of the invention, the described downstream signal of described mapping block carrying comprises business datum signal.

Utilize technical scheme provided by the invention, realize pre-coding power normalization parameter is transferred to receiving terminal, solved the problem of transmission of multi-user MIMO pre-encoding power normalization parameter.According to embodiments of the invention, pre-coding power normalization parameter is carried on the different resource time-frequency domain in each antenna pilot position, between each antenna, there is not interference, system is easy to demodulation and obtains transmitting power normalized parameter.Or pre-coding power normalization parameter is carried on the identical resource time-frequency domain in each antenna pilot position, by precoding, distinguishes, reduce the consumption of system resource.Or transmitting power normalized parameter is carried in business datum, does not need the extra resource of system that takies, and in the situation that user increases, the utilization of system resource can be not influenced yet.Utilize technical scheme provided by the invention, simple, efficient, be conducive to further elevator system performance.

Accompanying drawing explanation

Fig. 1 is the embodiment schematic flow sheet of transmission pre-coding power normalization parameter of the present invention;

Fig. 2 is the mapping patterns of the embodiment of the present invention four antenna descending pilot frequencies on time-frequency domain;

Fig. 3 is the mapping pattern of another embodiment of the present invention descending pilot frequency on time-frequency domain;

Fig. 4 is the structural representation that the present invention sends pre-coding power normalization parameter base station equipment.

Embodiment

Below in conjunction with drawings and Examples, the specific embodiment of the present invention is described in further detail:

The sending, receiving method and the equipment that the invention provides a kind of pre-coding power normalization parameter, be transferred to receiving terminal to realize by pre-coding power normalization parameter.Technical scheme of the present invention, the problem of transmission of solution multi-user MIMO pre-encoding power normalization parameter, makes correctly detection signal of receiving terminal, uses technical scheme provided by the invention, and realization is simply, efficiently.

The sending method that the invention provides a kind of pre-coding power normalization parameter, comprises the following steps: the upward signal that base station receiving terminal sends, obtains the channel information between the many antennas in base station and terminal according to upward signal; Base station adopts precoding algorithm to calculate pre-coding matrix corresponding to down time-frequency resource, utilizes pre-coding matrix to calculate the transmitting power normalized parameter of running time-frequency resource; Base station is carried on transmitting power normalized parameter in downstream signal, to send to terminal.

As shown in Figure 1, be embodiments of the invention flow chart, below in conjunction with the flow chart of embodiment, the present invention is launched to elaborate.

S101: base station receives upward signal.In S101, the upward signal that base station sends by receiving terminal, the relevant information of understanding down channel.

No matter be cellular mobile communication or WLAN (wireless local area network), be two-way communication, up-downgoing channel can be Frequency Division Duplexing (FDD) or time division duplex communication.In the present embodiment, take cellular mobile communication as example, adopt MIMO multi-antenna technology base station to send downstream signal to terminal, the upward signal that receiving terminal sends simultaneously.Base station can obtain the relevant information of down channel in several ways, for example, in the information sending, wherein includes the metrical information of terminal to base station down signal in terminal.

In addition,, as embodiments of the invention, for the communication system TD-SCDMA of TDD time division duplex, can obtain by following steps the relevant information of down channel:

The ascending pilot frequency that base station sends according to terminal, estimates up channel information between the many antennas in base station and terminal; By interpolation algorithm, base station can obtain the channel information on up all running time-frequency resources; For tdd systems, within the enough short time, for example, in 10ms or shorter time, according to the characteristic of channel of tdd systems, can think that the characteristic of channel of up-downgoing remains unchanged, base station can obtain according to the channel information on up all running time-frequency resources the channel information on descending all running time-frequency resources.

As embodiments of the invention, channel matched can, according to multi-user's channel performance, be carried out to multi-user in base station.After base station obtains the channel information between the many antennas in base station and terminal according to upward signal, base station is selected N user and is carried out multiuser MIMO transmission from multi-user, and wherein N, for being greater than 1, is less than or equal to the integer of antenna for base station number.

Take below and simplify Greedy criterion as example explanation selection user's process.

First, the best user of base station selected channel quality, as primary user, selects user k by following formula ^*:

$k^{*}=\arg \underset{i}{\max }{\left|\right|h_i\left|\right|}^2,$ Upgrade selected user's number N _s=1, upgrade user S set={ k ^*, calculate this user's the rate of delivering a letter:

$R\left(S\right)={\log }_2(1+\frac{{\left|\right|h_{k^{*}}\left|\right|}^2}{{\mathrm{\σ}}^2}).$

Then, base station, from remaining user, selects a user and primary user to form one group, and channel capacity is maximized.For example select user m ^*, make capacity: $m*=\underset{m}{\arg \max }R\left(S^p\right)=\underset{m}{\arg \max }{\log }_2(1+\frac{1}{\mathrm{tr}\left({\mathrm{VV}}^H\right){\mathrm{\σ}}^2}),$ S wherein ^p=S ∪ m}, matrix v represents pre-coding matrix:

V=H ^h(HH ^h) ^-1, wherein $H={\left[\begin{array}{cccc}{h}_{j_1}& h_{j_2}& \·\·\·& h_{j_{\left|S^p\right|}}\end{array}\right]}^T,$

operator wherein | A| represents the size of set A.

If R is (S ∪ { m ^*) >R (S), so: S=S ∪ { m ^*, N _s=| S|, otherwise, S, N _sremain unchanged.

Increase progressively successively user, make to increase the user and the primary user that come in and form one group, and channel capacity is maximized, until number of users reaches N.

S102: transmitting power normalized parameter is determined in base station.In S102, base station adopts precoding algorithm to calculate pre-coding matrix corresponding to down time-frequency resource, and utilizes pre-coding matrix to determine the transmitting power normalized parameter of running time-frequency resource.

As embodiments of the invention, described precoding algorithm can be linear preequalization precoding algorithm, can be also non-linear preequalization precoding algorithm.In order to set forth better inventive concept of the present invention, below in conjunction with various precoding algorithms, describe the present invention.

The Mathematical Modeling of considering MIMO transmission channel is:

y＝Hx+n (1)

Wherein, x is the emission signal vector on the many antennas of transmitting terminal, and y is the received signal vector on the many antennas of receiving terminal, and H is transmission channel matrix, and n is white Gaussian noise vector.

For the linear preequalization algorithm of ZF of the transmitting terminal precoding based on ZF, the precoded signal of transmitting terminal is:

$x=\tilde{F}a---\left(2\right)$

Wherein, $\tilde{F}=\mathrm{\β}{H}^{+},$ H ⁺the pseudoinverse that represents H.

Reception data vector y at receiving terminal is:

$y=\frac{1}{\mathrm{\β}}(\mathrm{Hx}+n)=\frac{1}{\mathrm{\β}}(H\tilde{F}a+n)=a+\frac{1}{\mathrm{\β}}n---\left(3\right),$

Wherein, $\mathrm{\β}=\sqrt{K/\mathrm{trace}\left({\mathrm{HH}}^H\right)}---\left(4\right)$ For guaranteeing the constant power normalization parameter of transmit signal power.Wherein, K is transmitted signal number, and the inverse that is multiplied by power normalization parameter at receiving terminal compensates.

Transmitted signal is by realizing at the linear predictive coding of making a start with preequalization matrix multiple, and the precoding vectors of formation is by after channel, and receiving terminal does not need, through detecting, just can directly by demodulation, be transmitted.Preequalization algorithm based on ZF is better at channel condition, and the correlation of channel matrix H hour can effectively have been eliminated the interference between each antenna.

For based on least mean-square error MMSE preequalization algorithm, building preequalization matrix

shi Caiyong MMSE criterion, makes to receive the error mean square value of signal at receiving terminal minimum:

$\tilde{F}=\underset{\mathrm{\β},\mathrm{\ϵ}}{\arg \min }\mathrm{\ϵ}\left\{{\left|\right|{\mathrm{\β}}^{-1}(\mathrm{HF}\hat{a}+n)-a\left|\right|}^2\right\}---\left(5\right).$ Equally, the transmitting power of the vector that transmits after transmitting terminal precoding is constant, and performance number is constant:

$\mathrm{\ϵ}\left\{{\left|\right|\mathrm{Fa}\left|\right|}^2\right\}=K{\mathrm{\σ}}_a^2---\left(6\right),$ In formula, K represents the number that transmits,

represent transmit signal power.

According to MMSE algorithm criterion, obtaining optimized pre-coding matrix is:

$\tilde{F}={\mathrm{\βH}}^H{({\mathrm{HH}}^H+\frac{{\mathrm{\σ}}_n^2}{{\mathrm{\σ}}_a^2}I)}^{-1}---\left(7\right)$ Wherein, power normalization parameter $\mathrm{\β}=\sqrt{K/\mathrm{trace}\left({\tilde{F}\tilde{F}}^H\right)}$ (8), pre-coding matrix is $\tilde{F}={\mathrm{\βH}}^H{({\mathrm{HH}}^H+\frac{{\mathrm{\σ}}_n^2}{{\mathrm{\σ}}_a^2}I)}^{-1}.$

For two kinds of basic linear predictive coding algorithms set forth above, advantage is that algorithm is simple, and has eliminated the interference between antenna, is applicable to multi-user system.

For nonlinear precoding algorithm THP code calculation, first channel matrix H is carried out to QL decomposition, as follows:

H=F ^ts (9), wherein, matrix F is an orthogonal matrix, S is a lower triangular matrix.

In order to make the normalization that transmits, matrix B is had:

$B=\mathrm{diag}(\frac{1}{s_{11}},\·\·\·,\frac{1}{s_{\mathrm{KK}}})S---\left(10\right)$ Thereby making the element on the diagonal of the matrix B after normalization is 1.

By the thought of Interference Cancellation, the transmitting symbol of THP precoding is:

x ₁＝a ₁

x ₂＝mods _A(a ₂-b ₂₁x ₁)

…

$x_k=\mathrm{mod}{s}_A(a_k-{\mathrm{\Σ}}_{j=1}^{k-1}{b}_{\mathrm{kj}}{x}_j)---\left(11\right)$ , wherein, K is mimo system antenna number, a=[a ₁..., a _k] ^tfor source signal vector, x=[x ₁..., x _k] ^tfor precoded signal vector.Conventional letter a _kfor M-QAM modulation symbol, the real edge between modulation symbol be spaced apart [A/2, A/2), definition $A=\sqrt{M}.$ Modulo operation mods _a(x) object is in order to adjust transmitting power,

wherein, in order to keep constant transmitting power, power normalization parameter β can be taken as:

$\mathrm{\β}=\sqrt{\frac{K}{\underset{k=1}{\overset{K}{\mathrm{\Σ}}}\frac{1}{S_{\mathrm{kk}}^2}}}---\left(12\right).$

By transmitting through channel after precoding, the reception signal of receiving end is:

${\tilde{y}}_K={\mathrm{\Σ}}_{k=1}^K{b}_{\mathrm{Kk}}{x}_k+{\tilde{n}}_K$

${=x_K\mathrm{\Σ}}_{k=1}^{K-1}{b}_{\mathrm{Kk}}{x}_k+{\tilde{n}}_K---\left(13\right).$

After modular arithmetic:

${\mathrm{mod}s}_A\left({\tilde{y}}_K\right)={\mathrm{mod}s}_A(a_K-{{\mathrm{\Σ}}_{k=1}^{K-1}{b}_{\mathrm{Kk}}{x}_k+\mathrm{\Σ}}_{k=1}^{K-1}{b}_{\mathrm{Kk}}{x}_k+{\tilde{n}}_K)$

$={\mathrm{mod}s}_A(a_k+{\tilde{n}}_K)----\left(14\right).$

After THP precoding, signal is no longer the point on planisphere, but be evenly distributed in, gets in a region.

For auxiliary (LR) algorithm of Ge Yuejian, suppose that the transmitting data for different user is a _i, be the lattice point on an integer lattice or half-integer lattice, the cartesian product that transmitting data vector a is these sub-constellation space.So, whole reception constellation point also should be contained in Z ^2Mspace.At transmitting terminal, when adopt channel to invert method time, transmit exactly to be parallel to H ⁺the hypercube of classifying limit as in point.If data are Z ^2Minterior integral point, transmitting is exactly by H ⁺point in the grid space generating.If H ⁺the norm of a certain row very large, transmit so accordingly and just need very large transmitting power, by the point with less norm with other, replace these points, can reduce transmitting power.The core concept of the auxiliary precoding algorithm of lattice yojan is: in the situation that not changing lattice structure, for transmitting, adopt suitable supporting zone to carry out the transmitting power of minimized average.

Same, consider a N transmitting antenna, K single antenna user's mimo system, adopts Ge Yuejian aided algorithm for the pseudoinverse H of its channel matrix ⁺carry out accurate orthogonalization, suppose H _red=H ⁺u is H ⁺almost orthogonal matrix, U:K * K is modular matrix, a is primary signal, so

x＝H _reda′＝H ⁺Ua′

A '=mods _a(U ^-1a) (15), wherein, H _redcomputational methods can adopt Lenstra-Lenstra-Lovasz reduction method.X is the actual transmit signal on transmitting antenna, if adopt M-QAM modulation, $A=\sqrt{M}.$

At receiving terminal, adopt mods _acomputing detects original transmitted signal, receives signal to be:

y＝Hx+n＝HH ⁺Umods _A(U ^-1u)+n

＝Umods _A(U ^-1u)+n

=mods _a(UU ^-1u)+n=mods _a(u)+n (16), because modular matrix does not change lattice structure, so the auxiliary precoding algorithm of Ge Yuejian can be recovered and be transmitted by modular arithmetic.Meanwhile, this algorithm is by the pseudoinverse H to channel matrix ⁺accurate orthogonalization and modular arithmetic reduced widely the transmitting power transmitting, and reduced the booster action to noise.

Wherein, power normalization parameter β is

$\mathrm{\β}=\sqrt{\frac{K{\mathrm{\σ}}_a^2}{\mathrm{trace}\left({\mathrm{XX}}^H\right)}}---\left(17\right)$

According to different precoding algorithms, can by formula (4), (8), (12), (17), calculate respectively the power normalization parameter β at corresponding running time-frequency resource place.

Obviously, the above-mentioned introduction to various precodings, only, for explaining the present invention, is not intended to limit protection scope of the present invention.

S103: base station is carried on transmitting power normalized parameter to send to terminal in downstream signal.

In MIMO communication system, owing at transmitting terminal, the information that will send having been carried out to precoding processing, transmitting power has been carried out to normalized, for BPSK, QPSK, the such phase modulation method of 8PSK, the convergent-divergent of amplitude can not affect the information that phase place is carried, receiving terminal is without knowing just correct hard decision of power normalization parameter, concerning can be not to receiving terminal transmitted power normalized parameter without coded system, but concerning having coded system, can affect the value of soft bit, and then affect decode results.Therefore, transmitting power normalized parameter must be sent to receiving terminal, receiving terminal is demodulating data better.

Cell mobile communication systems TD-LTE below in conjunction with TDD mode is described, and without loss of generality, with base station 4 antennas, the configuring condition of the every user's single antenna of 4 user is example.

As shown in Figure 2, be a kind of descending pilot frequency of TD-LTE existing standard mapping pattern on time-frequency.As embodiments of the invention, transmitting power normalized parameter is carried in down-bound pilot frequency signal and sends to terminal, and in the present embodiment, downstream signal is modulated and sent to terminal by OFDM.In conjunction with concrete condition, can carry out following three steps:

The first step: the β parameter at corresponding pilot tone place is mapped in the pilot tone of corresponding pilot frequency locations of each antenna by pilot frequency design respectively.For base station 4 antennas, the configuring condition of the every user's single antenna of 4 user, base station 4 antennas should adopt respectively the pilot frequency design shown in Fig. 2, wherein R ₀, R ₁, R ₂, R ₃represent pilot frequency locations, the time-frequency domain resources of making fork is illustrated in this time-frequency domain and does not send data.Because the pilot frequency locations of each antenna is different, this pilot frequency design does not disturb between each antenna.

Second step: be multiplied by respectively the contrary of each independent channel.The pilot signal and the modulated signal that are located at pilot frequency locations are respectively: a={a ₁a ₂, a ₃, a ₃and x={x ₁, x ₂, x ₃, x ₄.Have: $x_1=\mathrm{\β}{a}_1{h}_{11}^{-1},$ $x_2=\mathrm{\β}{a}_2{h}_{22}^{-1},$ $x_3=\mathrm{\β}{a}_3{h}_{33}^{-1},$ $x_4=\mathrm{\β}{a}_4{h}_{44}^{-1}.$ Wherein, h _ijthe channel of expression from antenna for base station i to j user antenna, subscript-1 represents to invert, as

the channel of expression from antenna for base station 1 to user's 1 pilot frequency locations contrary.

The 3rd step: the business datum after precoding processing and pilot signal are mapped to the many antenna transmissions in base station after IFFT processes and go out.

In the above-described embodiments, because each pilot frequency locations is different, do not have interference between each antenna, carrying transmitting power normalized parameter need to take certain system resource, and obviously, in the more situation of user, resource consumption also increases.

In addition, transmitting power normalized parameter can be mapped in pilot tone, and carry out sending to again terminal after precoding processing to shining upon rear described pilot resources.For example, when transmitting power normalized parameter is carried on pilot tone pattern as shown in Figure 3, in conjunction with concrete condition, can carry out following three steps:

The first step: the β parameter at corresponding pilot tone place is mapped in the pilot tone of corresponding pilot frequency locations of each antenna by the pilot frequency design shown in Fig. 3 respectively, wherein R ₀represent pilot frequency locations.Because the pilot frequency locations of each antenna is overlapping, between multi-user, exist and disturb, will be by adopting method for precoding to eliminate interference.

Second step: carry out precoding and disturb inhibition to process.After being located at the pilot signal of pilot frequency locations and precoding, signal is respectively: a={a ₁a ₂a ₃a ₃} ^tand x={x ₁x ₂x ₃x ₄t.Have:

$x=\tilde{F}a,$ Wherein, when for ZF algorithm criterion $\tilde{F}=\mathrm{\β}{H}^{+},$ Or work as for MMSE algorithm criterion $\tilde{F}=\mathrm{\β}{H}^H{({\mathrm{HH}}^H+\frac{{\mathrm{\σ}}_n^2}{{\mathrm{\σ}}_a^2}I)}^{-1},$ For other algorithms, so analogize.H is the mimo channel matrix between base station and each user, matrix element h _ijthe channel of expression from antenna for base station i to j user antenna.

The 3rd step: the business datum after precoding processing and pilot signal are mapped to the many antenna transmissions in base station after IFFT processes and go out.

In the above-described embodiments, because each pilot frequency locations is different, do not have interference between each antenna, the system resource that carrying transmitting power normalized parameter need to take is less, and in the situation that user increases, the consumption of system resource can not increase.

In addition, transmitting power normalized parameter can also be carried on business datum signal, now the modulation system of described business datum is constant amplitude phase-modulation.Preferably, can carry out sending to again terminal after precoding processing to the described business datum signal time-frequency domain resources of carrying transmitting power normalized parameter.For example, when transmitting power normalized parameter is carried on pilot tone pattern as shown in Figure 3, in conjunction with concrete condition, can carry out following three steps:

The first step: pilot tone still adopts pilot frequency design mapping as shown in Figure 3, but now pilot frequency locations transmission is no longer the known pilot signal of receiving terminal user, but with the business datum signal of the such constant amplitude phase-modulation of BPSK, QPSK, 8PSK, by these business datum signals, carry out the incidentally β parameter at corresponding running time-frequency resource place.Because the pilot frequency locations of each antenna is overlapping, between multi-user, exist and disturb, need to adopt method for precoding to eliminate and disturb.

Second step: carry out precoding and disturb to suppress process, be located at the business datum signal of pilot frequency locations and precoding after signal be respectively: a={a ₁a ₂a ₃a ₃} ^tand x={x ₁x ₂x ₃x ₄} ^t.Have:

$x=\tilde{F}a,$ Wherein, when for ZF algorithm criterion $\tilde{F}=\mathrm{\β}{H}^{+},$ Or work as for MMSE algorithm criterion $\tilde{F}=\mathrm{\β}{H}^H{({\mathrm{HH}}^H+\frac{{\mathrm{\σ}}_n^2}{{\mathrm{\σ}}_a^2}I)}^{-1},$ For other algorithms, so analogize.H is the mimo channel matrix between base station and each user, matrix element h _ijthe channel of expression from antenna for base station i to j user antenna.

The 3rd step: the business datum after precoding processing and pilot signal are mapped to the many antenna transmissions in base station after IFFT processes and go out.

In the above-described embodiments, due to the place resource transmission of carrying transmitting power normalized parameter be business datum, do not need the extra resource of system that takies, and in the situation that user increases, the utilization of system resource can be not influenced yet.

In the above-described embodiments, the precoding algorithm of employing can be linear algorithm, can be also nonlinear algorithm.Preferably, when described precoding algorithm is linear predictive coding algorithm, described base station is carried on described transmitting power normalized parameter corresponding to described running time-frequency resource in downstream signal, to send to described terminal; When described precoding algorithm is nonlinear precoding algorithm, described base station is carried on the average of described transmitting power normalized parameter corresponding to described running time-frequency resource in downstream signal, to send to described terminal.For example, in the above-described embodiments, all in pilot frequency locations, carry out transmitting power normalized parameter and carry, different, what described pilot frequency locations can be carried is pilot tone, and what also can carry is business datum.Therefore, for linear predictive coding algorithm, the β value that the transmitting power normalized parameter carrying is described pilot frequency locations, for nonlinear precoding algorithm, the transmitting power normalized parameter carrying is the average of described pilot frequency locations β value around.

The present invention also provides a kind of method of reseptance of pre-coding power normalization parameter, comprises the following steps: terminal receives the downstream signal that base station sends, and downstream signal carries transmitting power normalized parameter information; Terminal is determined the mode of system bearing transmitting power normalized parameter, by downstream signal, obtains described transmitting power normalized parameter.Terminal, by modes such as receiving system message, can be obtained the mode of system bearing transmitting power normalized parameter, thereby from downstream signal, obtain transmitting power normalized parameter.

Obviously, the method for reseptance of pre-coding power normalization parameter is determined by sending method.As embodiments of the invention, downstream signal comprises down-bound pilot frequency signal, and when transmitting power normalized parameter is carried in down-bound pilot frequency signal, terminal is carried out demodulation to the signal of pilot frequency locations, and restituted signal is power normalization parameter.

As another embodiment of the present invention, downstream signal comprises business datum signal, wherein the modulation system of business datum is constant amplitude phase-modulation, the signal demodulation of terminal to business time-frequency position, and the amplitude divided by modulation constellation after delivery is power normalization parameter.

As shown in Figure 4, the present invention also provides a kind of base station equipment 400, comprising: receiver module 410, the upward signal that receiver module 410 sends for receiving terminal; Precoding module 420, precoding module 420, for according to the upward signal of receiver module 410 receptions, is determined the transmitting power normalized parameter of the downstream signal that base station equipment 400 sends; Sending module 430, sending module 430 sends to terminal for described transmitting power normalized parameter is carried on to downstream signal.

As the embodiment of the said equipment, precoding module 420 comprises:

Channel estimation module 421, channel estimation module 421, for according to described upward signal, obtains estimating descending channel information between base station equipment antenna more than 400 and terminal;

Computing module 422, computing module 422 adopts precoding algorithm to calculate pre-coding matrix corresponding to down time-frequency resource, utilizes pre-coding matrix to calculate the transmitting power normalized parameter of running time-frequency resource;

Mapping block 423, mapping block 423 is mapped in transmitting power normalized parameter on described downstream signal running time-frequency resource, by downstream signal, sends to terminal.

Preferably, the downstream signal of mapping block 423 mappings comprises down-bound pilot frequency signal.

Preferably, the downstream signal of mapping block 423 mappings comprises business datum signal.

The above is only the preferred embodiment of the present invention; it should be pointed out that for those skilled in the art, under the premise without departing from the principles of the invention; can also make some improvements and modifications, these improvements and modifications also should be considered as protection scope of the present invention.

Claims (9)

1. a sending method for pre-coding power normalization parameter, is characterized in that, comprises the following steps:

The upward signal that base station receiving terminal sends, obtains the channel information between the many antennas in described base station and described terminal according to described upward signal;

Described base station, according to described channel information, adopts precoding algorithm to calculate pre-coding matrix corresponding to down time-frequency resource, utilizes described pre-coding matrix to calculate the transmitting power normalized parameter of described running time-frequency resource;

Described base station is carried on described transmitting power normalized parameter in downstream signal, to send to described terminal, wherein, described downstream signal comprises down-bound pilot frequency signal, and transmitting power normalized parameter is mapped in pilot tone, and the pilot signal after mapping is carried out sending to terminal after precoding; Or described downstream signal comprises business datum signal, and, the running time-frequency resource of the business datum signal of carrying transmitting power normalized parameter is carried out sending to terminal after precoding processing again.

2. the sending method of pre-coding power normalization parameter as claimed in claim 1, is characterized in that, the channel information obtaining between the many antennas in described base station and described terminal according to described upward signal comprises:

The ascending pilot frequency that described base station sends according to described terminal, estimates up channel information between the many antennas in described base station and described terminal;

By interpolation algorithm, described base station obtains the channel information on up all running time-frequency resources;

According to the characteristic of channel of tdd systems, described base station obtains the channel information on descending all running time-frequency resources according to the channel information on up all running time-frequency resources.

3. the sending method of pre-coding power normalization parameter as claimed in claim 1, it is characterized in that, after base station obtains the channel information between the many antennas in described base station and described terminal according to described upward signal, described base station is selected N user and is carried out multiuser MIMO transmission from multi-user, wherein N is for being greater than 1, the integer that is less than or equal to antenna for base station number, comprises the following steps:

The best user of described base station selected channel quality is as primary user;

Described base station, from remaining user, selects a user and described primary user to form one group, and channel capacity is maximized;

Increase progressively successively user, make to increase the user and the described primary user that come in and form one group, and channel capacity is maximized, until number of users reaches N.

4. the sending method of pre-coding power normalization parameter as claimed in claim 1, it is characterized in that, described precoding algorithm comprises: zero forcing algorithm, least-mean-square error algorithm, block diagonalization algorithm, THP algorithm, Ge Yuejian aided algorithm or Ge Yuejian auxiliary vector precoding algorithm.

5. the sending method of pre-coding power normalization parameter as claimed in claim 1, is characterized in that, described downstream signal is ofdm modulation signal, and described transmitting power normalized parameter is carried in described pilot tone.

6. the sending method of pre-coding power normalization parameter as claimed in claim 1, is characterized in that, and the modulation system of described business datum is constant amplitude phase-modulation.

7. the sending method of pre-coding power normalization parameter as claimed in claim 1, is characterized in that, described downstream signal is ofdm modulation signal, and described transmitting power normalized parameter is carried on described business datum signal running time-frequency resource.

8. the sending method of the pre-coding power normalization parameter as described in any one in claim 1 to 7, is characterized in that,

When described precoding algorithm is linear predictive coding algorithm, described base station is carried on described transmitting power normalized parameter corresponding to described running time-frequency resource in downstream signal, to send to described terminal;

When described precoding algorithm is nonlinear precoding algorithm, described base station is carried on the average of described transmitting power normalized parameter corresponding to described running time-frequency resource in downstream signal, to send to described terminal.

9. a base station equipment, is characterized in that, comprising:

Receiver module, the upward signal that described receiver module sends for receiving terminal;

Precoding module, described precoding module, for according to the upward signal of described receiver module reception, is determined the transmitting power normalized parameter of the downstream signal that described base station equipment sends;

Sending module, described sending module sends to described terminal for described transmitting power normalized parameter is carried on to downstream signal;

Wherein, described precoding module comprises:

Channel estimation module, described channel estimation module, for according to described upward signal, obtains estimating descending channel information between the many antennas of described base station equipment and described terminal;

Computing module, described computing module adopts precoding algorithm to calculate pre-coding matrix corresponding to down time-frequency resource, utilizes described pre-coding matrix to calculate the transmitting power normalized parameter of described running time-frequency resource;

Mapping block, described mapping block is carried on described transmitting power normalized parameter on described downstream signal running time-frequency resource, by downstream signal, sends to described terminal;

Wherein, the described downstream signal of described mapping block carrying comprises down-bound pilot frequency signal, and transmitting power normalized parameter is mapped in pilot tone, and the pilot signal after mapping is being carried out by sending module, sending to terminal after precoding; Or the described downstream signal of described mapping block carrying comprises business datum signal, and, the running time-frequency resource of the business datum signal of carrying transmitting power normalized parameter is being carried out after precoding processing, then sending to terminal by sending module.

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