CN101355410B - Method and system for transmitting data based on random beam shaping - Google Patents

Abstract

The invention discloses a method for transmitting data based on random wave beam shaping, comprising the following steps: a base station terminal generates a beam shaping unitary matrix with constant amplitude for each element and random variable phase position; the base station terminal transmits a plurality of different training symbols to user equipment through the unitary matrix; the user equipment feeds back a received maximum value in a plurality of SINR corresponding to a launching beam and a corresponding number of the launching beam to a base station; and the base station selects the user equipment corresponding to the maximum SINR in the beam for different launching beams for data transmission. The method is applicable to arbitrary number of launching antennae, not only ensures the same amplitude for all the elements of a beam shaping matrix so as to significantly reduce the requirement on a dynamic range of a power amplifier and realize the random beam shaping technology with only one set of phase switcher as well, but also can obtain the same thuoughput as the prior random beam shaping system.

Description

A kind of data transmission method and system based on accidental beam shaping

Technical field

The present invention relates to wireless communication technology field, particularly relate to a kind of data transmission method and system based on accidental beam shaping.

Background technology

MIMO (Multiple-Input Multiple-Output, multiple-input and multiple-output) communication system is by adopting many to transmit and receive antenna and have gain of higher spatial reuse and diversity gain, and can obtain significant multi-user diversity gain by the multi-subscriber dispatching technology in multi-user system, so it will become the key technology of next generation wireless communication system.In mimo system, can utilize beam forming technique to obtain certain beam shaping gain by the signal on the different transmit antennas is weighted.But conventional beam forming technique needs higher computation complexity and feedback complexity.

At present, a kind of employing OBS (Opportunistic Beamforming System, the accidental beam shaping system) wireless communication technology, have that beam forming technique is simple, the feedback complexity is low, and can obtain the advantages such as throughput of system of identical growth rate when having the complete channel state information at transmitter and utilizing dpc techniques, so be subjected to extensive attention.But, this technology adopts conventional unitary matrice as the beam shaping matrix, therefore the amplitude of its each element and phase place are respectively [0,1) and [0,2 π) interior change at random (as shown in Figure 1), and the linear dynamic range of practical communication system intermediate power amplifier is very limited, so the change at random of amplitude can the serious efficient that reduces power amplifier.

In order to address the above problem, a kind of employing OCS (OpportunisticCophasing System appears now, random wave bundle homophase formation system) wireless communication technology, this technology is considered under relevant fully fading channel, because all transmitting antennas are identical to the channel gain of reception antenna, therefore propose the phase place of a randomly changing beam shaping vector, and there is no need the thought of its amplitude of randomly changing.This technology is the accidental beam shaping technology that a kind of multi-beam is launched simultaneously, goes for multi-user system.But this technology only is only applicable to number of transmit antennas and is no more than 3 mimo system at present.

Summary of the invention

The problem that the embodiment of the invention will solve provides a kind of data transmission method and system based on accidental beam shaping, only is only applicable to the defective that number of transmit antennas is no more than 3 mimo system to overcome existing OCS technology.

For achieving the above object, the technical scheme of the embodiment of the invention provides a kind of method of transfer of data, may further comprise the steps: the base station end generates the constant amplitude of each element, the beam shaping unitary matrice C of phase place change at random; The base station end utilizes described unitary matrice C to send a plurality of different training symbols to subscriber equipment; Maximum among the SINR that a plurality of and launching beam that subscriber equipment receives to base station feedback is corresponding (Signal-to-Interference-plus-Noise Ratio, Signal Interference and Noise Ratio) and corresponding launching beam numbering; Described base station is that different launching beams select the pairing subscriber equipment of maximum SINR in this wave beam to carry out transfer of data.

Wherein, generate in the step of beam shaping unitary matrice C of constant amplitude, phase place change at random of each element, specifically comprise at described base station end:

At the initial moment t of cycle of training, the base station end produce at random M [0,2 π) equally distributed phase theta in the scope _t=[θ ₁θ ₂θ _M];

The base station end produces the Fourier matrix of a M * M dimension

$F=\frac{1}{\sqrt{\mathrm{<figure-callout\; id="1"\; label="M"\; filenames="S2008101265979E00031.png,S2008101265979E00041.png"\; state="\{\{state\}\}">M</figure-callout>}}}\left[\begin{array}{cccccc}1& 1& .& .& .& 1\\ 1& w& .& .& .& w^{M-1}\\ .& .& .& & & .\\ .& .& & .& & .\\ .& .& & & .& .\\ 1& w^{M-1}& .& .& .& w^{(M-1)(M-1)}\end{array}\right]$

W=e wherein ^{-j2 π/M}

With phase vectors θ _tColumn element be added in accordingly above the phase place of all elements of each row of matrix F, obtain the accidental beam shaping matrix:

$C=\frac{1}{\sqrt{M}}\left[\begin{array}{cccccc}{e}^{{\mathrm{j\&theta;}}_1}& e^{j{\mathrm{\&theta;}}_2}& .& .& .& e^{j{\mathrm{\&theta;}}_M}\\ e^{j{\mathrm{\&theta;}}_1}& e^{j(-2\mathrm{\&pi;}/M+{\mathrm{\&theta;}}_2)}& .& .& .& e^{j(-2\mathrm{\&pi;}(M-1)/M+{\mathrm{\&theta;}}_M)}\\ .& .& .& & & .\\ .& .& & .& & .\\ .& .& & & .& .\\ e^{j{\mathrm{\&theta;}}_1}& e^{j(-2\mathrm{\&pi;}(M-1)/M+{\mathrm{\&theta;}}_2)}& .& .& .& e^{j(-2\mathrm{\&pi;}(M-1)(M-1)/M+{\mathrm{\&theta;}}_M)}\end{array}\right]$

Wherein, generate in the step of beam shaping unitary matrice C of constant amplitude, phase place change at random of each element, also can adopt following method, specifically comprise at described base station end:

At the initial moment t of cycle of training, produce an initialization vector c _t∈ C ^{1 * M},

$c_t=\left[\begin{array}{cccc}{e}^{{\mathrm{j\&theta;}}_1}& e^{{\mathrm{j\&theta;}}_2}& \&CenterDot;\&CenterDot;\&CenterDot;& e^{{\mathrm{j\&theta;}}_M}\end{array}\right]$

Wherein, θ _m, m=1 ..., M be separate and [0,2 π) in equally distributed random phase;

Produce a Fourier matrix F ∈ C ^{M * M},

$F=\frac{1}{\sqrt{\mathrm{<figure-callout\; id="1"\; label="M"\; filenames="S2008101265979E00031.png,S2008101265979E00041.png"\; state="\{\{state\}\}">M</figure-callout>}}}\left[\begin{array}{cccccc}1& 1& .& .& .& 1\\ 1& w& .& .& .& w^{M-1}\\ .& .& .& & & .\\ .& .& & .& & .\\ .& .& & & .& .\\ 1& w^{M-1}& .& .& .& w^{(M-1)(M-1)}\end{array}\right]$

Wherein, w=e ^{-j2 π/M}

Structure accidental beam shaping Matrix C

$C=\left[\begin{array}{cccc}{c}_1& {\mathrm{<figure-callout\; id="2"\; label="c"\; filenames="S2008101265979E00051.png"\; state="\{\{state\}\}">c</figure-callout>}}_2& \&CenterDot;\&CenterDot;\&CenterDot;& c_M\end{array}\right]$

$=\left[\begin{array}{cccc}{c}_t\left(1\right)F(:,1)& c_t\left(2\right)F(:,2)& \&CenterDot;\&CenterDot;\&CenterDot;& c_t\left(M\right)F(:,M)\end{array}\right]$

$=\frac{1}{\sqrt{M}}\left[\begin{array}{cccccc}{e}^{{\mathrm{j\&theta;}}_1}& e^{j{\mathrm{\&theta;}}_2}& .& .& .& e^{j{\mathrm{\&theta;}}_M}\\ e^{j{\mathrm{\&theta;}}_1}& e^{j(-2\mathrm{\&pi;}/M+{\mathrm{\&theta;}}_2)}& .& .& .& e^{j(-2\mathrm{\&pi;}(M-1)/M+{\mathrm{\&theta;}}_M)}\\ .& .& .& & & .\\ .& .& & .& & .\\ .& .& & & .& .\\ e^{j{\mathrm{\&theta;}}_1}& e^{j(-2\mathrm{\&pi;}(M-1)/M+{\mathrm{\&theta;}}_2)}& .& .& .& e^{j(-2\mathrm{\&pi;}(M-1)(M-1)/M+{\mathrm{\&theta;}}_M)}\end{array}\right]$

Wherein, c _m=c _t(m) F (:, m) ∈ C ^{M * 1}, m=1 ..., M is the accidental beam shaping vector of corresponding m launching beam.

Wherein, in the maximum and the step of corresponding launching beam numbering of described subscriber equipment in the corresponding SINR of a plurality of and launching beam that base station feedback receives,

Described wave beam numbering

By formula

${\hat{m}}_k=\arg \underset{m=1,\&CenterDot;\&CenterDot;\&CenterDot;,M}{\max }\left|h_k{c}_m\right|,$ k＝1，…，K

Determine, wherein h _k=[h ₁₁h ₁₂H _1M] ∈ C ^{1 * M}Be that the complex channel vector between the subscriber equipment k is arrived in the base station;

Maximum among the described SINR

By formula

${\widehat{\mathrm{\&gamma;}}}_k=\arg \underset{m=1,\&CenterDot;\&CenterDot;\&CenterDot;,M}{\max }{\mathrm{\&gamma;}}_{m,k}$

Determine, wherein γ _{M, k}Be the SINR of corresponding m the launching beam of subscriber equipment k.

Wherein, the SINR γ of corresponding m the launching beam of described subscriber equipment k _{M, k}By formula

${\mathrm{\&gamma;}}_{m,k}=\frac{\frac{\mathrm{\&rho;}}{M}{\left|h_k{c}_m\right|}^2}{1+\frac{\mathrm{\&rho;}}{M}\underset{l=1,l\&NotEqual;m}{\overset{M}{\mathrm{\&Sigma;}}}{\left|h_k{c}_l\right|}^2},$ m＝1，…，M，k＝1，…，K

Determine that wherein ρ is user's average received SNR (Signal to Noise Ratio, a signal to noise ratio).

Wherein, be that different launching beams select the pairing subscriber equipment of maximum SINR in this wave beam to carry out specifically comprising in the step of transfer of data in described base station:

Be provided with and M the data acquisition system S that launching beam is corresponding _m, m=1 ..., M stores the feedback information of all subscriber equipmenies;

Select subscriber equipment, for the feedback information of subscriber equipment k

When ${\hat{m}}_k=m$ The time, ${\widehat{\mathrm{\&gamma;}}}_k\&Element;S_m,$ The subscriber equipment of described selection is by formula

${\hat{k}}_m=\arg \underset{{\widehat{\mathrm{\&gamma;}}}_k\&Element;S_n}{\max }{\widehat{\mathrm{\&gamma;}}}_k,$ m＝1，…，M

Determine;

Utilize launching beam m to carry out transfer of data to the subscriber equipment of described selection.

The technical scheme of the embodiment of the invention also provides a kind of system of transfer of data, comprise: the base station end, be used to generate the constant amplitude of each element, the beam shaping unitary matrice C of phase place change at random, and utilize described unitary matrice C to send a plurality of different training symbols to subscriber equipment; Subscriber equipment, maximum in the corresponding SINR of a plurality of and launching beam that base station feedback receives and corresponding launching beam numbering; The base station is selected the pairing subscriber equipment of maximum SINR in this wave beam for different launching beams and is carried out transfer of data.

Wherein, described base station end comprises: the phase place generation unit, be used for generating at random a plurality of [0,2 π) equally distributed phase place in the scope; Fourier matrix generation unit is used to generate the Fourier matrix that a M * M ties up; Accidental beam shaping matrix generation unit is used for obtaining the accidental beam shaping matrix according to the phase place of described phase place generation unit generation and the Fourier matrix of described Fourier matrix generation unit generation.

Wherein, described subscriber equipment comprises: the maximum acquiring unit among the SINR is used for obtaining the maximum of the corresponding SINR of a plurality of and launching beam that receives; Wave beam numbering acquiring unit is used for obtaining the corresponding launching beam numbering of maximum that the maximum acquiring unit with described SINR obtains.

Compare with existing OCS technology, technical scheme of the present invention has following advantage:

The present invention is applicable to number of transmit antennas arbitrarily; The present invention had both guaranteed that the amplitude of all elements of beam shaping matrix was identical, this can significantly reduce the requirement to the power amplifier dynamic range, and, only just can realize the accidental beam shaping technology, can obtain again and traditional identical throughput of system of accidental beam shaping system with one group of phase shifter.

Description of drawings

Fig. 1 is the structured flowchart of a kind of accidental beam shaping system of prior art;

Fig. 2 is the flow chart of method of a kind of transfer of data of the embodiment of the invention;

Fig. 3 is the structured flowchart of multi-beam accidental beam shaping of the present invention system;

Fig. 4 is that the present invention adopts phase shifter to realize the structured flowchart of multi-beam accidental beam shaping system;

Fig. 5 is the frame structure schematic diagram that the present invention adopts;

Fig. 6 is the simulation result of throughput of the present invention and traditional accidental beam shaping system and the numerical result schematic diagram of theoretical throughput computing formula.

Embodiment

Below in conjunction with drawings and Examples, the specific embodiment of the present invention is described in further detail.Following examples are used to illustrate the present invention, but are not used for limiting the scope of the invention.

The flow process of a kind of data transmission method based on accidental beam shaping of the embodiment of the invention comprises the following steps: as shown in Figure 2

Step s201, base station end generate the constant amplitude of each element, the beam shaping unitary matrice C of phase place change at random.Detailed process is:

At the initial moment t of cycle of training, the base station end produce at random M [0,2 π) equally distributed phase theta in the scope _t=[θ ₁θ ₂θ _M];

The base station end produces the Fourier matrix of a M * M dimension

$F=\frac{1}{\sqrt{\mathrm{<figure-callout\; id="1"\; label="M"\; filenames="S2008101265979E00031.png,S2008101265979E00041.png"\; state="\{\{state\}\}">M</figure-callout>}}}\left[\begin{array}{cccccc}1& 1& .& .& .& 1\\ 1& w& .& .& .& w^{M-1}\\ .& .& .& & & .\\ .& .& & .& & .\\ .& .& & & .& .\\ 1& w^{M-1}& .& .& .& w^{(M-1)(M-1)}\end{array}\right]$

W=e wherein ^{-j2 π/M}

With phase vectors θ _tColumn element be added in accordingly above the phase place of all elements of each row of matrix F, obtain the accidental beam shaping matrix

$C=\frac{1}{\sqrt{M}}\left[\begin{array}{cccccc}{e}^{{\mathrm{j\&theta;}}_1}& e^{j{\mathrm{\&theta;}}_2}& .& .& .& e^{j{\mathrm{\&theta;}}_M}\\ e^{j{\mathrm{\&theta;}}_1}& e^{j(-2\mathrm{\&pi;}/M+{\mathrm{\&theta;}}_2)}& .& .& .& e^{j(-2\mathrm{\&pi;}(M-1)/M+{\mathrm{\&theta;}}_M)}\\ .& .& .& & & .\\ .& .& & .& & .\\ .& .& & & .& .\\ e^{j{\mathrm{\&theta;}}_1}& e^{j(-2\mathrm{\&pi;}(M-1)/M+{\mathrm{\&theta;}}_2)}& .& .& .& e^{j(-2\mathrm{\&pi;}(M-1)(M-1)/M+{\mathrm{\&theta;}}_M)}\end{array}\right]$

In the present embodiment, can also generate unitary matrice C in the following way:

At the initial moment t of cycle of training, produce an initialization vector c _t∈ C ^{1 * M},

$c_t=\left[\begin{array}{cccc}{e}^{{\mathrm{j\&theta;}}_1}& e^{{\mathrm{j\&theta;}}_2}& \&CenterDot;\&CenterDot;\&CenterDot;& e^{{\mathrm{j\&theta;}}_M}\end{array}\right]$

Wherein, θ _m, m=1 ..., M be separate and [0,2 π) in equally distributed random phase;

Produce a Fourier matrix F ∈ C ^{M * M},

$F=\frac{1}{\sqrt{\mathrm{<figure-callout\; id="1"\; label="M"\; filenames="S2008101265979E00031.png,S2008101265979E00041.png"\; state="\{\{state\}\}">M</figure-callout>}}}\left[\begin{array}{cccccc}1& 1& .& .& .& 1\\ 1& w& .& .& .& w^{M-1}\\ .& .& .& & & .\\ .& .& & .& & .\\ .& .& & & .& .\\ 1& w^{M-1}& .& .& .& w^{(M-1)(M-1)}\end{array}\right]$

Wherein, w=e ^{-j2 π/M}

Structure accidental beam shaping Matrix C:

$C=\left[\begin{array}{cccc}{c}_1& {\mathrm{<figure-callout\; id="2"\; label="c"\; filenames="S2008101265979E00051.png"\; state="\{\{state\}\}">c</figure-callout>}}_2& \&CenterDot;\&CenterDot;\&CenterDot;& c_M\end{array}\right]$

$=\left[\begin{array}{cccc}{c}_t\left(1\right)F(:,1)& c_t\left(2\right)F(:,2)& \&CenterDot;\&CenterDot;\&CenterDot;& c_t\left(M\right)F(:,M)\end{array}\right]$

$=\frac{1}{\sqrt{M}}\left[\begin{array}{cccccc}{e}^{{\mathrm{j\&theta;}}_1}& e^{j{\mathrm{\&theta;}}_2}& .& .& .& e^{j{\mathrm{\&theta;}}_M}\\ e^{j{\mathrm{\&theta;}}_1}& e^{j(-2\mathrm{\&pi;}/M+{\mathrm{\&theta;}}_2)}& .& .& .& e^{j(-2\mathrm{\&pi;}(M-1)/M+{\mathrm{\&theta;}}_M)}\\ .& .& .& & & .\\ .& .& & .& & .\\ .& .& & & .& .\\ e^{j{\mathrm{\&theta;}}_1}& e^{j(-2\mathrm{\&pi;}(M-1)/M+{\mathrm{\&theta;}}_2)}& .& .& .& e^{j(-2\mathrm{\&pi;}(M-1)(M-1)/M+{\mathrm{\&theta;}}_M)}\end{array}\right]$

Wherein, c _m=c _t(m) F (:, m) ∈ C ^{M * 1}, m=1 ..., M is the accidental beam shaping vector of corresponding m launching beam.

Step s202, base station end utilize unitary matrice C to send a plurality of different training symbols to subscriber equipment.

Step s203, maximum among the corresponding SINR of a plurality of and launching beam that subscriber equipment receives to base station feedback and corresponding launching beam numbering.Described wave beam numbering

By formula

${\hat{m}}_k=\arg \underset{m=1,\&CenterDot;\&CenterDot;\&CenterDot;,M}{\max }\left|h_k{c}_m\right|,$ k＝1，…，K

Determine, wherein h _k=[h ₁₁h ₁₂H _1M] ∈ C ^{1 * M}Be that the complex channel vector between the subscriber equipment k is arrived in the base station;

Maximum among the described SINR

By formula

${\widehat{\mathrm{\&gamma;}}}_k=\arg \underset{m=1,\&CenterDot;\&CenterDot;\&CenterDot;,M}{\max }{\mathrm{\&gamma;}}_{m,k}$

Determine, wherein γ _{M, k}Be the SINR of corresponding m the launching beam of subscriber equipment k.

The SINR γ of corresponding m the launching beam of described subscriber equipment k _{M, k}By formula

${\mathrm{\&gamma;}}_{m,k}=\frac{\frac{\mathrm{\&rho;}}{M}{\left|h_k{c}_m\right|}^2}{1+\frac{\mathrm{\&rho;}}{M}\underset{l=1,l\&NotEqual;m}{\overset{M}{\mathrm{\&Sigma;}}}{\left|h_k{c}_l\right|}^2},$ m＝1，…，M，k＝1，…，K

Determine that wherein ρ is subscriber equipment average received SNR.

Step s204, the base station is that different launching beams select the pairing subscriber equipment of maximum SINR in this wave beam to carry out transfer of data.Detailed process is:

Be provided with and M the data acquisition system S that launching beam is corresponding _m, m=1 ..., M stores the feedback information of all subscriber equipmenies;

Select subscriber equipment, for the feedback information of subscriber equipment k

When ${\hat{m}}_k=m$ The time, ${\widehat{\mathrm{\&gamma;}}}_k\&Element;S_m,$ The subscriber equipment of described selection is by formula

${\hat{k}}_m=\arg \underset{{\widehat{\mathrm{\&gamma;}}}_k\&Element;S_n}{\max }{\widehat{\mathrm{\&gamma;}}}_k,$ m＝1，…，M

Determine;

Launching beam m carries out transfer of data to the subscriber equipment of described selection

When adopting multi-beam accidental beam shaping system shown in Figure 3, have K user with one below, the M transmit antennas is adopted in the base station, and it is example that each user only adopts the system of single reception antenna of N=1, and concrete implementation step of the present invention is as follows:

Certain cycle of training (Frame is divided into two parts: cycle of training and

Data transfer cycles, initial moment t as shown in Figure 5) produces an initialization vector c _t∈ C ^{1 * M},

$c_t=\left[\begin{array}{cccc}{e}^{{\mathrm{j\&theta;}}_1}& e^{{\mathrm{j\&theta;}}_2}& \&CenterDot;\&CenterDot;\&CenterDot;& e^{{\mathrm{j\&theta;}}_M}\end{array}\right]---\left(1\right)$

Wherein, θ _m, m=1 ..., M be separate and [0,2 π) in equally distributed random phase;

2. produce a Fourier matrix F ∈ C ^{M * M},

$F=\frac{1}{\sqrt{\mathrm{<figure-callout\; id="1"\; label="M"\; filenames="S2008101265979E00031.png,S2008101265979E00041.png"\; state="\{\{state\}\}">M</figure-callout>}}}\left[\begin{array}{cccccc}1& 1& .& .& .& 1\\ 1& w& .& .& .& w^{M-1}\\ .& .& .& & & .\\ .& .& & .& & .\\ .& .& & & .& .\\ 1& w^{M-1}& .& .& .& w^{(M-1)(M-1)}\end{array}\right]---\left(2\right)$

Wherein, w=e ^{-j2 π/M}

3. the accidental beam shaping Matrix C is constructed as follows

$C=\left[\begin{array}{cccc}{c}_1& {\mathrm{<figure-callout\; id="2"\; label="c"\; filenames="S2008101265979E00051.png"\; state="\{\{state\}\}">c</figure-callout>}}_2& \&CenterDot;\&CenterDot;\&CenterDot;& c_M\end{array}\right]$

$=\left[\begin{array}{cccc}{c}_t\left(1\right)F(:,1)& c_t\left(2\right)F(:,2)& \&CenterDot;\&CenterDot;\&CenterDot;& c_t\left(M\right)F(:,M)\end{array}\right]$

$=\frac{1}{\sqrt{M}}\left[\begin{array}{cccccc}{e}^{{\mathrm{j\&theta;}}_1}& e^{j{\mathrm{\&theta;}}_2}& .& .& .& e^{j{\mathrm{\&theta;}}_M}\\ e^{j{\mathrm{\&theta;}}_1}& e^{j(-2\mathrm{\&pi;}/M+{\mathrm{\&theta;}}_2)}& .& .& .& e^{j(-2\mathrm{\&pi;}(M-1)/M+{\mathrm{\&theta;}}_M)}\\ .& .& .& & & .\\ .& .& & .& & .\\ .& .& & & .& .\\ e^{j{\mathrm{\&theta;}}_1}& e^{j(-2\mathrm{\&pi;}(M-1)/M+{\mathrm{\&theta;}}_2)}& .& .& .& e^{j(-2\mathrm{\&pi;}(M-1)(M-1)/M+{\mathrm{\&theta;}}_M)}\end{array}\right]---\left(3\right)$

Wherein, c _m=c _t(m) F (:, m) ∈ C ^{M * 1}, m=1 ..., M is the accidental beam shaping vector of corresponding m launching beam.Obviously, Matrix C remains unitary matrice, but the constant amplitude of its each element is

This can significantly reduce the requirement to the power amplifier dynamic range.And the phase place of each row all elements of C is exactly the needed phase place of phase shifter in as shown in Figure 4 each launching beam.

In addition, three steps in front also can produce under offline mode.For example, produce earlier M [0,2 π) in equally distributed random phase θ _t=[θ ₁θ ₂θ _M], produce Fourier matrix F ∈ C then ^{M * M}, at last directly θ _tEach element correspondence be added on the phase place of all elements of each row of F; This can realize by phase shifter.As long as number of transmit antennas M is certain, F is exactly constant so, in the time of therefore each the training, only needs to produce phase vectors θ _tThat's all.

4. at receiving terminal, the wave beam with the maximum SINR of reception of user k correspondence is numbered

For

${\hat{m}}_k=\arg \underset{m=1,\&CenterDot;\&CenterDot;\&CenterDot;,M}{\max }\left|h_k{c}_m\right|,$ k＝1，…，K (4)

Wherein, h _k=[h ₁₁h ₁₂H _1M] ∈ C ^{1 * M}Be that the complex channel vector between the user k is arrived in the base station.The SINR of corresponding m the launching beam of user k is

${\mathrm{\&gamma;}}_{m,k}=\frac{\frac{\mathrm{\&rho;}}{M}{\left|h_k{c}_m\right|}^2}{1+\frac{\mathrm{\&rho;}}{M}\underset{l=1,l\&NotEqual;m}{\overset{M}{\mathrm{\&Sigma;}}}{\left|h_k{c}_l\right|}^2},$ m＝1，…，M，k＝1，…，K (5)

So, the maximum SINR that obtained on M launching beam of user k is

${\widehat{\mathrm{\&gamma;}}}_k=\arg \underset{m=1,\&CenterDot;\&CenterDot;\&CenterDot;,M}{\max }{\mathrm{\&gamma;}}_{m,k}---\left(6\right)$

So the feedback information of user k is

5. in the base station, be provided with and M the data acquisition system S that launching beam is corresponding _m, m=1 ..., M stores all users' feedback information.For example, for the feedback information of user k

If ${\hat{m}}_k=m,$ So ${\widehat{\mathrm{\&gamma;}}}_k\&Element;S_m.$ At last, at launching beam m, the user who is scheduled is

${\hat{k}}_m=\arg \underset{{\widehat{\mathrm{\&gamma;}}}_k\&Element;S_m}{\max }{\widehat{\mathrm{\&gamma;}}}_k,$ m＝1，…，M (7)

6. transfer of data is carried out at the selected user of each launching beam in the base station.

7. when reception antenna quantity was 1, the throughput R of system can approximate expression be

R≈Mlog ₂(1+a+0.5772b) (8)

Wherein, parameter a is separating of following transcendental equation

$a+\frac{(M-1)\mathrm{\&rho;}}{m_{0}M}\ln (a+1)=\frac{\mathrm{\&rho;}}{m_{0}M}\ln K---\left(9\right)$

Wherein, parameter m ₀The fading factor of expression Nakagami-m fading channel, ρ is the average received SNR of subscriber equipment in the system.Although a also can dominance ground approximate representation be

$a=\frac{\mathrm{\&rho;}}{m_{0}M}\ln K-\frac{(M-1)\mathrm{\&rho;}}{m_{0}M}\ln (\frac{\mathrm{\&rho;}}{m_{0}M}\ln K+1)+O\left(\ln \ln \ln K\right)---\left(10\right)$

But the convergence rate of this approximate expression is very slow, and causes existing than mistake between the numerical result that obtains according to formula (8) and the simulation result.Fortunately, the exact solution of parameter a can be searched for equation (9) with the method for exhaustion at an easy rate and be obtained.At last, parameter b can be expressed as

$b=\frac{\mathrm{\&rho;}(a+1)}{m_{0}M(a+1)+\mathrm{\&rho;}(M-1)}---\left(11\right)$

Wherein, the numerical result schematic diagram of the simulation result of the throughput of the present invention and traditional accidental beam shaping system and theoretical throughput computing formula as shown in Figure 6.

The system of a kind of transfer of data of the embodiment of the invention comprises the base station end, is used to generate the constant amplitude of each element, the beam shaping unitary matrice C of phase place change at random, and utilizes described unitary matrice C to send a plurality of different training symbols to subscriber equipment; Subscriber equipment is used for maximum and the corresponding launching beam numbering of the corresponding SINR of a plurality of and launching beam that receives to base station feedback; The base station is used to different launching beams to select the pairing subscriber equipment of maximum SINR in this wave beam to carry out transfer of data.

The base station end comprises the phase place generation unit, be used for generating at random a plurality of [0,2 π) equally distributed phase place in the scope; Fourier matrix generation unit is used to generate the Fourier matrix of a multidimensional; Accidental beam shaping matrix generation unit is used for obtaining the accidental beam shaping matrix according to the phase place of described phase place generation unit generation and the Fourier matrix of described Fourier matrix generation unit generation.

Subscriber equipment comprises the maximum acquiring unit among the SINR, is used for obtaining the maximum of the corresponding SINR of a plurality of and launching beam that receives; Wave beam numbering acquiring unit is used for obtaining the corresponding launching beam numbering of maximum that the maximum acquiring unit with described SINR obtains.

Main feature of the present invention is the constant amplitude of all elements of multi-beam accidental beam shaping matrix and identical, therefore fixes at the amplification coefficient of the power amplifier of radio-frequency head, and this has just significantly reduced the requirement to its dynamic range; Even only need one group of phase-shifter just can realize transmit beam-forming; And, compare with the accidental beam shaping system of routine, can obtain identical throughput of system.

The above only is a preferred implementation of the present invention; should be pointed out that for those skilled in the art, under the prerequisite that does not break away from the technology of the present invention principle; can also make some improvements and modifications, these improvements and modifications also should be considered as protection scope of the present invention.

Claims (7)

1. the data transmission method based on accidental beam shaping is characterized in that, may further comprise the steps:

The base station end generates the constant amplitude of each element, the beam shaping unitary matrice C of phase place change at random;

The base station end utilizes described unitary matrice C to send a plurality of different training symbols to subscriber equipment;

Maximum among the corresponding Signal Interference and Noise Ratio SINR of a plurality of and launching beam that subscriber equipment receives to base station feedback and corresponding launching beam numbering;

Described base station is that different launching beams select the pairing subscriber equipment of maximum SINR in this wave beam to carry out transfer of data,

Wherein, the end detailed process of beam shaping unitary matrice C that generates constant amplitude, the phase place change at random of each element in described base station comprises:

At the initial moment t of cycle of training, described base station end produce at random M [0,2 π) equally distributed phase theta in the scope _t=[θ ₁θ ₂θ _M], wherein M is a number of transmit antennas;

The base station end produces the Fourier matrix of a M * M dimension

W=e wherein ^{-j2 π/M}

With phase vectors θ _tColumn element be added in accordingly above the phase place of all elements of each row of matrix F, obtain the accidental beam shaping matrix

Or specifically comprise:

At the initial moment t of cycle of training, produce an initialization vector c _t∈ C ^{1 * M},

$c_t=\left[\begin{array}{cccc}{e}^{{\mathrm{j\&theta;}}_1}& e^{{\mathrm{j\&theta;}}_2}& \&CenterDot;\&CenterDot;\&CenterDot;& e^{{\mathrm{j\&theta;}}_M}\end{array}\right]$

Wherein, θ _m, m=1 ..., M be separate and [0,2 π) in equally distributed random phase;

Produce a Fourier matrix F ∈ C ^{M * M},

Wherein, w=e ^{-j2 π/M}

Structure accidental beam shaping Matrix C:

Wherein, c _m=c _t(m) F (:, m) ∈ C ^{M * 1}, m=1 ..., M is the accidental beam shaping vector of corresponding m launching beam.

2. according to claim 1 based on the data transmission method of accidental beam shaping, it is characterized in that, in the maximum and the step of corresponding launching beam numbering of described subscriber equipment in the corresponding SINR of a plurality of and launching beam that base station feedback receives,

Described wave beam numbering By formula

${\hat{m}}_k=\arg \underset{m=1,\&CenterDot;\&CenterDot;\&CenterDot;,M}{\max }\left|h_k{c}_m\right|,k=1,\&CenterDot;\&CenterDot;\&CenterDot;,K$

Determine, wherein h _k=[h ₁₁h ₁₂H _1M] ∈ C ^{1 * M}Be that the complex channel vector between the subscriber equipment k is arrived in the base station;

Maximum among the described SINR

By formula

${\widehat{\mathrm{\&gamma;}}}_k=\arg \underset{m=1,\&CenterDot;\&CenterDot;\&CenterDot;,M}{\max }{\mathrm{\&gamma;}}_{m,k}$

Determine, wherein γ _{M, k}Be the SINR of corresponding m the launching beam of subscriber equipment k.

As described in the claim 2 based on the data transmission method of accidental beam shaping, it is characterized in that the SINR γ of corresponding m the launching beam of described subscriber equipment k _{M, k}By formula

${\mathrm{\&gamma;}}_{m,k}=\frac{\frac{\mathrm{\&rho;}}{M}{\left|h_k{c}_m\right|}^2}{1+\frac{\mathrm{\&rho;}}{M}\underset{l=1,l\&NotEqual;m}{\overset{M}{\mathrm{\&Sigma;}}}{\left|h_k{c}_l\right|}^2},m=1,\&CenterDot;\&CenterDot;\&CenterDot;,M,k=1,\&CenterDot;\&CenterDot;\&CenterDot;,K$

Determine that wherein ρ is user's average received signal to noise ratio snr.

As described in the claim 3 based on the data transmission method of accidental beam shaping, it is characterized in that, be that different launching beams select the pairing subscriber equipment of maximum SINR in this wave beam to carry out specifically comprising in the step of transfer of data in described base station:

Be provided with and M the data acquisition system S that launching beam is corresponding _m, m=1 ..., M stores the feedback information of all subscriber equipmenies;

Select subscriber equipment, for the feedback information of subscriber equipment k

When

The time, The subscriber equipment of described selection is by formula

${\hat{k}}_m=\arg \underset{{\widehat{\mathrm{\&gamma;}}}_k\&Element;S_m}{\max }{\widehat{\mathrm{\&gamma;}}}_k,m=1,\&CenterDot;\&CenterDot;\&CenterDot;,M$

Determine;

Launching beam m carries out transfer of data to the subscriber equipment of described selection.

5. the data transmission system based on accidental beam shaping is characterized in that, comprising:

The base station end is used to generate the constant amplitude of each element, the beam shaping unitary matrice C of phase place change at random, and utilizes described unitary matrice C to send a plurality of different training symbols to subscriber equipment;

Subscriber equipment is used for maximum and the corresponding launching beam numbering of the corresponding SINR of a plurality of and launching beam that receives to base station feedback;

The base station is used to different launching beams to select the pairing subscriber equipment of maximum SINR in this wave beam to carry out transfer of data,

Wherein, the end detailed process of beam shaping unitary matrice C that generates constant amplitude, the phase place change at random of each element in described base station comprises:

At the initial moment t of cycle of training, described base station end produce at random M [0,2 π) equally distributed phase theta in the scope _t=[θ ₁θ ₂θ _M], wherein M is a number of transmit antennas;

Described base station end produces the Fourier matrix of a M * M dimension

W=e wherein ^{-j2 π/M}

With phase vectors θ _tColumn element be added in accordingly above the phase place of all elements of each row of matrix F, obtain the accidental beam shaping matrix

Or specifically comprise:

At the initial moment t of cycle of training, produce an initialization vector c _t∈ C ^{1 * M},

$c_t=\left[\begin{array}{cccc}{e}^{{\mathrm{j\&theta;}}_1}& e^{{\mathrm{j\&theta;}}_2}& \&CenterDot;\&CenterDot;\&CenterDot;& e^{{\mathrm{j\&theta;}}_M}\end{array}\right]$

Wherein, θ _m, m=1 ..., M be separate and [0,2 π) in equally distributed random phase;

Produce a Fourier matrix F ∈ C ^{M * M},

Wherein, w=e ^{-j2 π/M}

Structure accidental beam shaping Matrix C:

Wherein, c _m=c _t(m) F (:, m) ∈ C ^{M * 1}, m=1 ..., M is the accidental beam shaping vector of corresponding m launching beam.

As described in the claim 5 based on the data transmission system of accidental beam shaping, it is characterized in that described base station end comprises:

The phase place generation unit, be used for generating at random a plurality of [0,2 π) equally distributed phase place in the scope;

Fourier matrix generation unit is used to generate the Fourier matrix that a M * M ties up;

Accidental beam shaping matrix generation unit is used for obtaining the accidental beam shaping matrix according to the phase place of described phase place generation unit generation and the Fourier matrix of described Fourier matrix generation unit generation.

As described in the claim 6 based on the data transmission system of accidental beam shaping, it is characterized in that described subscriber equipment comprises:

Maximum acquiring unit among the SINR is used for obtaining the maximum of the corresponding SINR of a plurality of and launching beam that receives;

Wave beam numbering acquiring unit is used for obtaining the corresponding launching beam numbering of maximum that the maximum acquiring unit with described SINR obtains.

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