CN1728592A - Method for constructing time-space group code in wireless communication - Google Patents

Abstract

First, a simplest real orthogonal matrix is constructed by the method. Then, high order, complicated real orthogonal matrix is constructed step by step. Finally, generalized complex orthogonal matrix corresponding to the said high order, complicated real orthogonal matrix is constructed so as to construct time-space group code suitable to equipping MIMO system with six or eight pieces of transmitting antenna, four pieces of receiving antenna. Comparing with space - time group code suggested by Alamouti, the invention increases number of transmitting antenna, constructs space - time group code in high order antenna number, i.e. realizing full diversity of MIMO system through high order antenna number based on Hurwitz-Radon theory, through orthogonal extending coded matrix. Comparing with current space - time group code, the invention possesses better system performance with features of quick operational speed, low system overhead.

Description

A kind of radio communication Space-Time Block Coding building method

Technical field:

The invention belongs to wireless communication field, it is particularly related to the structure multiple-input, multiple-output and (is called for short: MIMO) radio communication Space-Time Block Coding technology.

Background technology:

In recent years, research to MIMO (multiple-input, multiple-output) power system capacity makes the capacity of the on-air radio channel under the situation that adopts transmit diversity and receive diversity increase greatly, also make the researcher begin to hanker after the coded modulation diversity technique is organically combined, near the power system capacity of MIMO, empty time-code arises at the historic moment as far as possible.Empty time-code mainly is divided into space-time trellis codes (STTC), Space-Time Block Coding (STBC) and hierarchical space-time code (LASTC).The Space Time Transmit Diversity of having adopted among the WCDMA belongs to the special case of Space-Time Block Coding, in 2002, based on the space-time block code plan of transmission antenna diversity (STTD) typing the technical documentation of 3GPP, see document 3GPP TS 25.211 V3.11.0 (2002-06); Physical channels and mappingof transport channels onto physical channels (FDD) (Release 1999).The Space-Time Block Coding scheme in past concentrates on the design aspect based on low order number of transmit antennas or real signal, sees document [1.Siavash M.Alamouti.A Simple Transmit Diversity Technique For Wireless Communications。IEEE Journal onSelected Areas in Communications, Vol.16, No.8, Oct.1998:1451-1458.] [2.VahidTarokh, Hamid Jafarkhani, A.R.Calderbank.Space-Time Block Codes From OrthognalDesigns.IEEE Trans.Inform.Theory, Vol.45, No5, Jul.1999:1456-1467.] MIMO also is the effective ways that solve the greatest difficulty " multipath fading " that radio communication faces, and the Space-Time Block Coding technology that people's propositions such as Alamout and Tarokh are arranged causes that as a kind of core algorithm scheme people pay much attention to.Space-Time Block Coding is to the code word of the transmission employing orthogonal design of transmitting terminal, at the maximum-likelihood decoding algorithm of receiving terminal employing based on linear process.Maximum diversity gain when Space-Time Block Coding can guarantee given transmission and reception antenna, and decoding algorithm is very simple.Compared to other two kinds of empty time-codes, STBC has good performance, and system handles speed is increased substantially, and expense greatly reduces, and is fit to Project Realization, has very practical meaning.To only limiting to discuss general, there is not concrete system to realize based on the complex signal design under the high-order number of transmit antennas.By the relevant knowledge of information theory and radio communication as can be known: the characteristics of MIMO technology be utilize " multipath " and effect, it is favourable changing unfavorable; And can't bring into play the advantage of MIMO based on the design of low order antenna number, briefly, cause the increase rate of communication quality can not be enough satisfactory exactly; On the other hand, for complex signal, low excessively based on the design of real signal to the utilance of signal space, will cause system effectiveness low like this.

Summary of the invention:

The purpose of this invention is to provide a kind of radio communication Space-Time Block Coding building method, can construct the Space-Time Block Coding that is applicable to the mimo system that is equipped with six or eight transmitting antennas, four reception antennas according to the inventive method, this sign indicating number has fast operation, overhead is low, characteristics such as function admirable.

The invention provides a kind of building method of Space-Time Block Coding, it is characterized in that adopting following encoder matrix constitution step:

Step 1: construct a real orthogonal matrix the simplest:

The signaling channel symbol is x ₁(x ₁For greater than 0 real number), x ₂(x ₂Be real number), the channel symbol cycle is T, and they are carried out Space Time Coding, sends with two antennas according to following mode:

	Antenna 1	Antenna 2
			Time t	x 1	x 2
t+T	-x 2	x 1

Top coded system can be used matrix: $\left[\begin{array}{cc}{x}_1& x_2\\ -x_2& x_1\end{array}\right]---\left(1\right)$

Expression, it is an orthogonal matrix;

Step 2: increase transmitting antenna, make it to reach 8 antennas.Corresponding to the dimension (columns that is it is 8) that increases matrix in the step 1, just every transmit antennas is corresponding to row of encoder matrix, and we can expand to 8 * 8 orthogonal matrix to it by mending 0 method, mends 0 result to be:

$\left[\begin{array}{cccccccc}{x}_1& x_2& 0& 0& 0& 0& 0& 0\\ -x_2& x_1& 0& 0& 0& 0& 0& 0\\ 0& 0& x_1& x_2& 0& 0& 0& 0\\ 0& 0& -x_2& x_1& 0& 0& 0& 0\\ 0& 0& 0& 0& x_1& x_2& 0& 0\\ 0& 0& 0& 0& -x_2& x_1& 0& 0\\ 0& 0& 0& 0& 0& 0& x_1& x_2\\ 0& 0& 0& 0& 0& 0& -x_2& x_1\end{array}\right]---\left(2\right)$

Top matrix notation is sent out two real channel symbol x with 8 antennas, 8 time slots ₁, x ₂

Step 3:, increase the real channel symbol x of transmission in order to transmit more information ₃, x ₄, corresponding on the encoder matrix of step 2 gained, increasing real symbol x ₃, x ₄, promptly the corresponding 0 position real symbol x that mends in the matrix ₃, x ₄Replace, the orthogonal coding matrix after can obtaining substituting is as follows:

$\left[\begin{array}{cccccccc}{x}_1& x_2& x_3& x_4& 0& 0& 0& 0\\ -x_2& x_1& x_4& -x_3& 0& 0& 0& 0\\ -x_3& -x_4& x_1& x_2& 0& 0& 0& 0\\ -x_4& x_3& -x_2& x_1& 0& 0& 0& 0\\ 0& 0& 0& 0& x_1& x_2& x_3& x_4\\ 0& 0& 0& 0& -x_2& x_1& -x_4& x_3\\ 0& 0& 0& 0& -x_3& x_4& x_1& x_2\\ 0& 0& 0& 0& -x_4& -x_3& -x_2& x_1\end{array}\right]---\left(3\right)$

Above matrix notation with 8 antennas, 8 time slots are sent out four real channel symbol x ₁, x ₂, x ₃, x ₄

Step 4: further increase transmission information, increase channel real symbol x ₅And x ₆, corresponding on the encoder matrix of step 3 gained, increasing real symbol x ₅And x ₆, corresponding 0 position x in the matrix ₅And x ₆Replace, it is as follows to obtain substituting back orthogonal coding matrix:

$\left[\begin{array}{cccccccc}{x}_1& x_2& x_3& x_4& x_5& x_6& 0& 0\\ -x_2& x_1& x_4& -x_3& x_6& -x_5& 0& 0\\ -x_3& -x_4& x_1& x_2& 0& 0& -x_5& -x_6\\ -x_4& x_3& -x_2& x_1& 0& 0& x_6& -x_5\\ -x_5& -x_6& 0& 0& x_1& x_2& x_3& x_4\\ -x_6& x_5& 0& 0& {-x}_2& x_1& -x_4& x_3\\ 0& 0& x_5& -x_6& -x_3& x_4& x_1& x_2\\ 0& 0& x_6& x_5& {-x}_4& -x_3& -x_2& x_1\end{array}\right]---\left(4\right)$

Above matrix notation with 8 antennas, 8 time slots are sent out six real channel symbol x ₁, x ₂, x ₃, x ₄, x ₅, x ₆

Step 5: last, we need transmit 8 real channel symbol x ₁, x ₂, x ₃, x ₄, x ₅, x ₆, x ₇, x ₈, increase the real channel symbol x of transmission ₇And x ₈, corresponding to increasing real symbol x on the gained matrix in the step 4 ₈And x ₈, corresponding 0 position x in the matrix ₇And x ₈Replace, it is as follows to obtain final orthogonal coding matrix X:

$X=\left[\begin{array}{cccccccc}{x}_1& x_2& x_3& x_4& x_5& x_6& x_7& x_8\\ -x_2& x_1& x_4& -x_3& x_6& -x_5& -x_8& x_7\\ {-x}_3& -x_4& x_1& x_2& x_7& x_8& -x_5& -x_6\\ -x_4& x_3& -x_2& x_1& x_8& -x_7& x_6& -x_5\\ -x_5& -x_6& -x_7& -x_8& x_1& x_2& x_3& x_4\\ -x_6& x_5& -x_8& x_7& -x_2& x_1& -x_4& x_3\\ -x_7& x_8& x_5& -x_6& {-x}_3& x_4& x_1& x_2\\ -x_8& -x_7& x_6& x_5& {-x}_4& -x_3& -x_2& x_1\end{array}\right]---\left(5\right)$

Above matrix notation with 8 antennas, 8 time slots are sent out eight real channel symbol x ₁, x ₂, x ₃, x ₄, x ₅, x ₆, x ₇, x ₈

Step 6: the multiple encoder matrix of the pairing generalized orthogonal of real orthogonal coding matrix X that constitution step 5 obtains:

In practice, channel symbol generally all has plural form, and therefore, we are necessary to introduce the plural form of real orthogonal matrix X.Can carry out following processing (makes plural number with all elements of matrix here and considers, be i.e. x _i=Re (x _i)+jIm (x _i), i=1,2 ..., 8, wherein, $j=$ $\sqrt{-1}):$ Here Re (x) is meant the real part of getting x, and Im (x) is meant the imaginary part of getting x.

We have obtained real orthogonal coding matrix X the front, equally we use the same method (repeating step 1～5) obtain another real orthogonal coding matrix X ':

$X^{\&prime;}=\left[\begin{array}{cccccccc}{\mathrm{<figure-callout\; id="1"\; label="x"\; filenames="A20041004030500162.png"\; state="\{\{state\}\}">x</figure-callout>}}_1^{\&prime;}& {\mathrm{<figure-callout\; id="2"\; label="x"\; filenames="A20041004030500162.png"\; state="\{\{state\}\}">x</figure-callout>}}_2^{\&prime;}& {\mathrm{<figure-callout\; id="3"\; label="x"\; filenames="A20041004030500162.png"\; state="\{\{state\}\}">x</figure-callout>}}_3^{\&prime;}& {\mathrm{<figure-callout\; id="4"\; label="x"\; filenames="A20041004030500162.png"\; state="\{\{state\}\}">x</figure-callout>}}_4^{\&prime;}& x_5^{\&prime;}& x_6^{\&prime;}& {\mathrm{<figure-callout\; id="7"\; label="x"\; filenames="A20041004030500162.png"\; state="\{\{state\}\}">x</figure-callout>}}_7^{\&prime;}& x_8^{\&prime;}\\ {-\mathrm{<figure-callout\; id="2"\; label="x"\; filenames="A20041004030500162.png"\; state="\{\{state\}\}">x</figure-callout>}}_2^{\&prime;}& x_1^{\&prime;}& x_4^{\&prime;}& -x_3^{\&prime;}& x_6^{\&prime;}& -x_5^{\&prime;}& {-x}_8^{\&prime;}& x_7^{\&prime;}\\ -x_3^{\&prime;}& -x_4^{\&prime;}& x_1^{\&prime;}& x_2^{\&prime;}& x_7^{\&prime;}& {\mathrm{<figure-callout\; id="8"\; label="x"\; filenames="A20041004030500162.png"\; state="\{\{state\}\}">x</figure-callout>}}_8^{\&prime;}& {-x}_5^{\&prime;}& -x_6^{\&prime;}\\ -{\mathrm{<figure-callout\; id="4"\; label="x"\; filenames="A20041004030500162.png"\; state="\{\{state\}\}">x</figure-callout>}}_4^{\&prime;}& {\mathrm{<figure-callout\; id="3"\; label="x"\; filenames="A20041004030500162.png"\; state="\{\{state\}\}">x</figure-callout>}}_3^{\&prime;}& {-\mathrm{<figure-callout\; id="2"\; label="x"\; filenames="A20041004030500162.png"\; state="\{\{state\}\}">x</figure-callout>}}_2^{\&prime;}& x_1^{\&prime;}& x_8^{\&prime;}& -x_7^{\&prime;}& x_6^{\&prime;}& -x_5^{\&prime;}\\ {-x}_5^{\&prime;}& -x_6^{\&prime;}& -x_7^{\&prime;}& -{\mathrm{<figure-callout\; id="8"\; label="x"\; filenames="A20041004030500162.png"\; state="\{\{state\}\}">x</figure-callout>}}_8^{\&prime;}& x_1^{\&prime;}& x_2^{\&prime;}& x_3^{\&prime;}& x_4^{\&prime;}\\ -x_6^{\&prime;}& x_5^{\&prime;}& -{\mathrm{<figure-callout\; id="8"\; label="x"\; filenames="A20041004030500162.png"\; state="\{\{state\}\}">x</figure-callout>}}_8^{\&prime;}& {\mathrm{<figure-callout\; id="7"\; label="x"\; filenames="A20041004030500162.png"\; state="\{\{state\}\}">x</figure-callout>}}_7^{\&prime;}& -{\mathrm{<figure-callout\; id="2"\; label="x"\; filenames="A20041004030500162.png"\; state="\{\{state\}\}">x</figure-callout>}}_2^{\&prime;}& x_1^{\&prime;}& -x_4^{\&prime;}& x_3^{\&prime;}\\ -{\mathrm{<figure-callout\; id="7"\; label="x"\; filenames="A20041004030500162.png"\; state="\{\{state\}\}">x</figure-callout>}}_7^{\&prime;}& x_8^{\&prime;}& x_5^{\&prime;}& -x_6^{\&prime;}& -x_3^{\&prime;}& x_4^{\&prime;}& x_1^{\&prime;}& x_2^{\&prime;}\\ -x_8^{\&prime;}& -x_7^{\&prime;}& x_6^{\&prime;}& x_5^{\&prime;}& -x_4^{\&prime;}& -x_3^{\&prime;}& -x_2^{\&prime;}& x_1^{\&prime;}\end{array}\right]---\left(6\right)$

X wherein ₁' be real number greater than 0, x ₂', x ₃', x ₄', x ₅', x ₆', x ₇', x ₈' be real number.

Then, the Generalized Complex Variable orthogonal matrix S of structure real matrix X correspondence ₈:

${\mathrm{<figure-callout\; id="8"\; label="S"\; filenames="A20041004030500162.png"\; state="\{\{state\}\}">S</figure-callout>}}_8=\left[\begin{array}{c}x+j{x}^{\&prime;}\\ x-j{x}^{\&prime;}\end{array}\right]---\left(7\right)$

Complex matrix S ₈Have following character:

$S_8^H\&CenterDot;{\mathrm{<figure-callout\; id="8"\; label="S"\; filenames="A20041004030500162.png"\; state="\{\{state\}\}">S</figure-callout>}}_8=\mathrm{\&rho;}\&CenterDot;I_8---\left(8\right)$

Wherein, the conjugate transpose of subscript " H " representing matrix, I ₈The unit square formation on one 8 rank of expression, ρ represents a constant, the size of ρ is:

$\mathrm{\&rho;}=2\left(\right|x_1{|}^2+|x_2{|}^2+\&CenterDot;\&CenterDot;\&CenterDot;+|x_8{|}^2+|x_1^{\&prime;}{|}^2+|x_2^{\&prime;}{|}^2+\&CenterDot;\&CenterDot;\&CenterDot;+\left|x_8^{\&prime;}{|}^2\right)$

$=2\underset{i=1}{\overset{8}{\mathrm{\&Sigma;}}}\left(\right|x_i{|}^2+\left|x_i^{\&prime;}{|}^2\right)$

(9)

This shows S ₈It is a broad sense complex orthogonal matrix.

${\mathrm{<figure-callout\; id="8"\; label="S"\; filenames="A20041004030500162.png"\; state="\{\{state\}\}">S</figure-callout>}}_8=\left[\begin{array}{cccccccc}{s}_1& s_2& s_3& s_4& s_5& s_6& s_7& s_8\\ -s_2& s_1& s_4& -s_3& s_6& -s_5& s_8& s_7\\ {-s}_3& -s_4& s_1& s_2& s_7& s_8& -s_5& {-s}_6\\ -s_4& s_3& -s_2& s_1& s_8& -s_7& s_6& -s_5\\ {-s}_5& -s_6& -s_7& -s_8& s_1& s_2& s_3& s_4\\ {-s}_6& s_5& -s_8& s_7& -s_2& s_1& {-s}_4& s_3\\ -s_7& s_8& s_5& -s_6& {-s}_3& s_4& s_1& {-s}_2\\ {-s}_8& {-s}_7& s_6& s_5& -s_4& -s_3& s_2& s_1\\ {\mathrm{<figure-callout\; id="1"\; label="s"\; filenames="A20041004030500162.png"\; state="\{\{state\}\}">s</figure-callout>}}_1^{*}& {\mathrm{<figure-callout\; id="2"\; label="s"\; filenames="A20041004030500162.png"\; state="\{\{state\}\}">s</figure-callout>}}_2^{*}& {\mathrm{<figure-callout\; id="3"\; label="s"\; filenames="A20041004030500162.png"\; state="\{\{state\}\}">s</figure-callout>}}_3^{*}& s_4^{*}& s_5^{*}& s_6^{*}& {\mathrm{<figure-callout\; id="7"\; label="s"\; filenames="A20041004030500162.png"\; state="\{\{state\}\}">s</figure-callout>}}_7^{*}& {\mathrm{<figure-callout\; id="8"\; label="s"\; filenames="A20041004030500162.png"\; state="\{\{state\}\}">s</figure-callout>}}_8^{*}\\ -{\mathrm{<figure-callout\; id="2"\; label="s"\; filenames="A20041004030500162.png"\; state="\{\{state\}\}">s</figure-callout>}}_2^{*}& {\mathrm{<figure-callout\; id="1"\; label="s"\; filenames="A20041004030500162.png"\; state="\{\{state\}\}">s</figure-callout>}}_1^{*}& {\mathrm{<figure-callout\; id="4"\; label="s"\; filenames="A20041004030500162.png"\; state="\{\{state\}\}">s</figure-callout>}}_4^{*}& -{\mathrm{<figure-callout\; id="3"\; label="s"\; filenames="A20041004030500162.png"\; state="\{\{state\}\}">s</figure-callout>}}_3^{*}& s_6^{*}& -s_5^{*}& -{\mathrm{<figure-callout\; id="8"\; label="s"\; filenames="A20041004030500162.png"\; state="\{\{state\}\}">s</figure-callout>}}_8^{*}& {\mathrm{<figure-callout\; id="7"\; label="s"\; filenames="A20041004030500162.png"\; state="\{\{state\}\}">s</figure-callout>}}_7^{*}\\ {-\mathrm{<figure-callout\; id="3"\; label="s"\; filenames="A20041004030500162.png"\; state="\{\{state\}\}">s</figure-callout>}}_3^{*}& -{\mathrm{<figure-callout\; id="4"\; label="s"\; filenames="A20041004030500162.png"\; state="\{\{state\}\}">s</figure-callout>}}_4^{*}& {\mathrm{<figure-callout\; id="1"\; label="s"\; filenames="A20041004030500162.png"\; state="\{\{state\}\}">s</figure-callout>}}_1^{*}& {\mathrm{<figure-callout\; id="2"\; label="s"\; filenames="A20041004030500162.png"\; state="\{\{state\}\}">s</figure-callout>}}_2^{*}& {\mathrm{<figure-callout\; id="7"\; label="s"\; filenames="A20041004030500162.png"\; state="\{\{state\}\}">s</figure-callout>}}_7^{*}& {\mathrm{<figure-callout\; id="8"\; label="s"\; filenames="A20041004030500162.png"\; state="\{\{state\}\}">s</figure-callout>}}_8^{*}& -s_5^{*}& {-s}_6^{*}\\ {-\mathrm{<figure-callout\; id="4"\; label="s"\; filenames="A20041004030500162.png"\; state="\{\{state\}\}">s</figure-callout>}}_4^{*}& {\mathrm{<figure-callout\; id="3"\; label="s"\; filenames="A20041004030500162.png"\; state="\{\{state\}\}">s</figure-callout>}}_3^{*}& -{\mathrm{<figure-callout\; id="2"\; label="s"\; filenames="A20041004030500162.png"\; state="\{\{state\}\}">s</figure-callout>}}_2^{*}& {\mathrm{<figure-callout\; id="1"\; label="s"\; filenames="A20041004030500162.png"\; state="\{\{state\}\}">s</figure-callout>}}_1^{*}& {\mathrm{<figure-callout\; id="8"\; label="s"\; filenames="A20041004030500162.png"\; state="\{\{state\}\}">s</figure-callout>}}_8^{*}& {-\mathrm{<figure-callout\; id="7"\; label="s"\; filenames="A20041004030500162.png"\; state="\{\{state\}\}">s</figure-callout>}}_7^{*}& s_6^{*}& {-s}_5^{*}\\ {-s}_5^{*}& {-s}_6^{*}& {-\mathrm{<figure-callout\; id="7"\; label="s"\; filenames="A20041004030500162.png"\; state="\{\{state\}\}">s</figure-callout>}}_7^{*}& {-\mathrm{<figure-callout\; id="8"\; label="s"\; filenames="A20041004030500162.png"\; state="\{\{state\}\}">s</figure-callout>}}_8^{*}& {\mathrm{<figure-callout\; id="1"\; label="s"\; filenames="A20041004030500162.png"\; state="\{\{state\}\}">s</figure-callout>}}_1^{*}& {\mathrm{<figure-callout\; id="2"\; label="s"\; filenames="A20041004030500162.png"\; state="\{\{state\}\}">s</figure-callout>}}_2^{*}& {\mathrm{<figure-callout\; id="3"\; label="s"\; filenames="A20041004030500162.png"\; state="\{\{state\}\}">s</figure-callout>}}_3^{*}& {\mathrm{<figure-callout\; id="4"\; label="s"\; filenames="A20041004030500162.png"\; state="\{\{state\}\}">s</figure-callout>}}_4^{*}\\ {-s}_6^{*}& s_5^{*}& {-\mathrm{<figure-callout\; id="8"\; label="s"\; filenames="A20041004030500162.png"\; state="\{\{state\}\}">s</figure-callout>}}_8^{*}& {\mathrm{<figure-callout\; id="7"\; label="s"\; filenames="A20041004030500162.png"\; state="\{\{state\}\}">s</figure-callout>}}_7^{*}& {-\mathrm{<figure-callout\; id="2"\; label="s"\; filenames="A20041004030500162.png"\; state="\{\{state\}\}">s</figure-callout>}}_2^{*}& {\mathrm{<figure-callout\; id="1"\; label="s"\; filenames="A20041004030500162.png"\; state="\{\{state\}\}">s</figure-callout>}}_1^{*}& {-\mathrm{<figure-callout\; id="4"\; label="s"\; filenames="A20041004030500162.png"\; state="\{\{state\}\}">s</figure-callout>}}_4^{*}& {\mathrm{<figure-callout\; id="3"\; label="s"\; filenames="A20041004030500162.png"\; state="\{\{state\}\}">s</figure-callout>}}_3^{*}\\ {-\mathrm{<figure-callout\; id="7"\; label="s"\; filenames="A20041004030500162.png"\; state="\{\{state\}\}">s</figure-callout>}}_7^{*}& {\mathrm{<figure-callout\; id="8"\; label="s"\; filenames="A20041004030500162.png"\; state="\{\{state\}\}">s</figure-callout>}}_8^{*}& s_5^{*}& -s_6^{*}& {-\mathrm{<figure-callout\; id="3"\; label="s"\; filenames="A20041004030500162.png"\; state="\{\{state\}\}">s</figure-callout>}}_3^{*}& s_4^{*}& {\mathrm{<figure-callout\; id="1"\; label="s"\; filenames="A20041004030500162.png"\; state="\{\{state\}\}">s</figure-callout>}}_1^{*}& {-\mathrm{<figure-callout\; id="2"\; label="s"\; filenames="A20041004030500162.png"\; state="\{\{state\}\}">s</figure-callout>}}_2^{*}\\ {-\mathrm{<figure-callout\; id="8"\; label="s"\; filenames="A20041004030500162.png"\; state="\{\{state\}\}">s</figure-callout>}}_8^{*}& {-\mathrm{<figure-callout\; id="7"\; label="s"\; filenames="A20041004030500162.png"\; state="\{\{state\}\}">s</figure-callout>}}_7^{*}& s_6^{*}& s_5^{*}& -{\mathrm{<figure-callout\; id="4"\; label="s"\; filenames="A20041004030500162.png"\; state="\{\{state\}\}">s</figure-callout>}}_4^{*}& {-\mathrm{<figure-callout\; id="3"\; label="s"\; filenames="A20041004030500162.png"\; state="\{\{state\}\}">s</figure-callout>}}_3^{*}& {\mathrm{<figure-callout\; id="2"\; label="s"\; filenames="A20041004030500162.png"\; state="\{\{state\}\}">s</figure-callout>}}_2^{*}& {\mathrm{<figure-callout\; id="1"\; label="s"\; filenames="A20041004030500162.png"\; state="\{\{state\}\}">s</figure-callout>}}_1^{*}\end{array}\right]---\left(10\right)$

S wherein ₁, s ₂... s ₈Be the complex channel symbol, and s _i=x _i+ jx _i' i=1,2...8.

Top matrix notation is with 8 antennas, by 8 complex channel symbol s of 16 time slots emissions ₁, s ₂... s ₈

Broad sense complex orthogonal matrix S ₈Be and comprise that 8 transmit antennas, 4 reception antennas (are called for short: the Space-Time Block Coding of mimo system 8 * 4);

In like manner, the Space-Time Block Coding method of the mimo system of structure 6 * 4 (i.e. 6 transmit antennas, 4 reception antennas) is S ₈The two row deletions of matrix back just can obtain 6 * 4 encoder matrix S ₆:

Top matrix notation is launched 8 complex channel symbol s with 6 antennas by 16 time slots ₁, s ₂... s ₈

Through after the above-mentioned steps, just can construct the Space-Time Block Coding of the mimo system that is applicable to six of outfits or eight transmitting antennas, four reception antennas.

Innovation part of the present invention is:

Compare with (2 * 2) Space-Time Block Coding that existing Alamouti proposes, the present invention is by the quadrature spread to encoder matrix, according to the Hurwitz-Radon theory, increase number of transmit antennas, constructed a kind of Space-Time Block Coding of high-order antenna number, promptly adopted the high-order antenna number to realize for the full-diversity on the mimo system, it has better system performance than more previously presented Space-Time Block Codings, channel capacity that within the specific limits can elevator system, and can improve communication quality.

(8 * 4) Space-Time Block Coding that uses method construct of the present invention is to be 8 transmit antennas, the space-time coding method of the mimo system design of 4 reception antennas, and it also is applicable to 8 transmit antennas, the situation of n root reception antenna; Equally, be to be 6 transmit antennas with the Space-Time Block Coding of (6 * 4) of this method construct, the mimo system design of 4 reception antennas, it also is applicable to 6 transmit antennas, the situation of n root reception antenna.

Advantage of the present invention:

The present invention has constructed the Space-Time Block Coding scheme of a kind of (8 * 4) and (6 * 4), and it is compared to previously presented Space-Time Block Coding following advantage:

1). this scheme is within the specific limits, communication quality and efficient under the wireless multi-path environment have effectively been improved, here the connotation of " certain limit " is meant: owing to be subject to the mimo channel capacity, antenna number is not unrestrictedly to increase, and is very little performance boost because the sharp increase of system handles operand brings.Can find out in the performance comparison diagram among Fig. 4 from Fig. 3;

2) though. because the complex signal of high-order mapping can more effectively be utilized signal space, but too small Euclidean distance will cause the serious reduction of radio communication decoding quality between signaling point, this scheme has been carried out compromise to this problem and has been considered, adopt suitable modulation scheme, guaranteed systematic function, adopt the different resulting performance curves of modulation system to make analysis to different empty time-codes among Fig. 4, can select the scheme that a kind of best empty time-code adds modulation system;

3). under identical modulation system, the performance of the Space-Time Block Coding of (8 * 4) is better than the performance of the Space-Time Block Coding of (6 * 4), as can be seen from Figure 3;

4). the present invention has effectively promoted radio communication quality and can guarantee suitable treatment effeciency.

Description of drawings:

Fig. 1 is a Space-Time Block Coding system radiating portion structured flowchart

Wherein n is a natural number;

Fig. 2 is the FB(flow block) of structure 8 * 4,6 * 4 Space-Time Block Codings;

Fig. 3 is the performance comparison curve that Space-Time Block Coding (STBC) adopts the QPSK modulation, and wherein curve 1 is represented the ber curve of (2 * 2) STBC, the ber curve of curve 2 representative (6 * 4) STBC, the ber curve of curve 3 representative (8 * 4) STBC; As can be seen, adopt identical modulation system, the systematic function of (8 * 4) STBC is best;

Fig. 4 is basic Space-Time Block Coding systematic function correlation curve.The situation of no code check that has compared the Space-Time Block Coding of some typical case respectively, wherein curve 4 is represented with (1 * 1) antennas, use the ber curve of 8PSK modulation mode, curve 5 expression (2 * 2) STBC, use the ber curve of 8PSK modulation mode, curve 6 expression (2 * 2) STBC, use the ber curve of QPSK modulation system, curve 7 shows (6 * 4) STBC, use the ber curve of 8PSK modulation mode, curve 8 expression (2 * 2) STBC, the ber curve of use BPSK modulation system, curve 9 expression (8 * 4) STBC, use the ber curve of 8PSK modulation mode, curve 10 expression (6 * 4) STBC, the ber curve of use QPSK modulation system, the Space-Time Block Coding new departure of (6 * 4) (adopting the QPSK modulation) can obtain good effect as can be seen.

Embodiment:

Using (8 * 4) Space-Time Block Coding of the inventive method structure is to be 8 transmit antennas, the space-time coding method of the mimo system design of 4 reception antennas, can make the Space-Time Block Coding device by the method for programming, cooperate hardware devices such as planisphere mapper and transmitting antenna, constitute Space-Time Block Coding system radiating portion.This Space-Time Block Coding system has this sign indicating number and has fast operation, and overhead is low, characteristics such as function admirable.

Claims (1)

1, a kind of building method of Space-Time Block Coding is characterized in that adopting following encoder matrix constitution step: step 1: construct a real orthogonal matrix the simplest:

The signaling channel symbol is x ₁(x ₁For greater than 0 real number), x ₂(x ₂Be real number), the channel symbol cycle is T, and they are carried out Space Time Coding, sends with two antennas according to following mode:

Antenna 1 antenna 2

Time t x ₁x ₂

t+T -x ₂ x ₁

Top coded system can be used matrix $\left[\begin{array}{cc}{x}_1& x_2\\ -x_2& x_1\end{array}\right]---\left(1\right)$

Expression, it is an orthogonal matrix;

Step 2: increase transmitting antenna, make it to reach 8 antennas.Corresponding to the dimension (columns that is it is 8) that increases matrix in the step 1, just every transmit antennas is corresponding to row of encoder matrix, and we can expand to 8 * 8 orthogonal matrix to it by mending 0 method, mends 0 result to be:

$\left[\begin{array}{cccccccc}{x}_1& x_2& 0& 0& 0& 0& 0& 0\\ {-x}_2& x_1& 0& 0& 0& 0& 0& 0\\ 0& 0& x_1& x_2& 0& 0& 0& 0\\ 0& 0& {-x}_2& x_1& 0& 0& 0& 0\\ 0& 0& 0& 0& x_1& x_2& 0& 0\\ 0& 0& 0& 0& {-x}_2& x_1& 0& 0\\ 0& 0& 0& 0& 0& 0& x_1& x_2\\ 0& 0& 0& 0& 0& 0& {-x}_2& x_1\end{array}\right]---\left(2\right)$

Step 3: increase the real channel symbol x of transmission ₃, x ₄, corresponding on the encoder matrix of step 2 gained, increasing real symbol x ₃, x ₄, promptly the corresponding 0 position real symbol x that mends in the matrix ₃, x ₄Replace, the orthogonal coding matrix after can obtaining substituting is as follows:

$\left[\begin{array}{cccccccc}{x}_1& x_2& x_3& x_4& 0& 0& 0& 0\\ {-x}_2& x_1& x_4& {-x}_3& 0& 0& 0& 0\\ {-x}_3& {-x}_4& x_1& x_2& 0& 0& 0& 0\\ {-x}_4& x_3& -x_2& x_1& 0& 0& 0& 0\\ 0& 0& 0& 0& x_1& x_2& x_3& x_4\\ 0& 0& 0& 0& {-x}_2& x_1& -x_4& x_3\\ 0& 0& 0& 0& -x_3& x_4& x_1& x_2\\ 0& 0& 0& 0& -x_4& -x_3& -x_2& x_1\end{array}\right]---\left(3\right)$

Step 4: increase channel real symbol x ₅And x ₆, corresponding on the encoder matrix of step 3 gained, increasing real symbol x ₅And x ₆, corresponding 0 position x in the matrix ₅And x ₆Replace, it is as follows to obtain substituting back orthogonal coding matrix:

$\left[\begin{array}{cccccccc}{x}_1& x_2& x_3& x_4& x_5& x_6& 0& 0\\ -x_2& x_1& x_4& -x_3& x_6& -x_5& 0& 0\\ -x_3& -x_4& x_1& x_2& 0& 0& -x_5& -x_6\\ -x_4& x_3& -x_2& x_1& 0& 0& x_6& -x_5\\ -x_5& -x_6& 0& 0& x_1& x_2& x_3& x_4\\ -x_6& x_5& 0& 0& -x_2& x_1& -x_4& x_3\\ 0& 0& x_5& -x_6& -x_3& x_4& x_1& x_2\\ 0& 0& x_6& x_5& -x_4& -x_3& -x_2& x_1\end{array}\right]---\left(4\right)$

Step 5: increase the real channel symbol x of transmission ₇And x ₈, corresponding to increasing real symbol x on the gained matrix in the step 4 ₇And x ₈, corresponding 0 position x in the matrix ₇And x ₈Replace, it is as follows to obtain final orthogonal coding matrix X:

$\left[\begin{array}{cccccccc}{x}_1& x_2& x_3& x_4& x_5& x_6& x_7& x_8\\ -x_2& x_1& x_4& -x_3& x_6& -x_5& -x_8& x_7\\ -x_3& -x_4& x_1& x_2& x_7& x_8& -x_5& -x_6\\ -x_4& x_3& -x_2& x_1& x_8& -x_7& x_6& -x_5\\ -x_5& -x_6& {-x}_7& -x_8& x_1& x_2& x_3& x_4\\ -x_6& x_5& -x_8& x_7& -x_2& x_1& -x_4& x_3\\ -x_7& x_8& x_5& -x_6& -x_3& x_4& x_1& x_2\\ -x_8& {-x}_7& x_6& x_5& -x_4& -x_3& -x_2& x_1\end{array}\right]---\left(5\right)$

Step 6: the multiple encoder matrix of the pairing generalized orthogonal of real orthogonal coding matrix X that constitution step 5 obtains:

We have obtained real orthogonal coding matrix X the front, equally we use the same method (repeating step 1～5) obtain another real orthogonal coding matrix X ':

$X^{\&prime;}=\left[\begin{array}{cccccccc}{x_1}^{\&prime;}& {x_2}^{\&prime;}& {x_3}^{\&prime;}& {x_4}^{\&prime;}& {x_5}^{\&prime;}& {x_6}^{\&prime;}& {x_7}^{\&prime;}& {x_8}^{\&prime;}\\ -{x_2}^{\&prime;}& {x_1}^{\&prime;}& {x_4}^{\&prime;}& -{x_3}^{\&prime;}& {x_6}^{\&prime;}& -{x_5}^{\&prime;}& {{-x}_8}^{\&prime;}& {x_7}^{\&prime;}\\ -{x_3}^{\&prime;}& -{x_4}^{\&prime;}& {x_1}^{\&prime;}& {x_2}^{\&prime;}& {x_7}^{\&prime;}& {x_8}^{\&prime;}& -{x_5}^{\&prime;}& -{x_6}^{\&prime;}\\ -{x_4}^{\&prime;}& {x_3}^{\&prime;}& -{x_2}^{\&prime;}& {x_1}^{\&prime;}& {x_8}^{\&prime;}& -{x_7}^{\&prime;}& {x_6}^{\&prime;}& -{x_5}^{\&prime;}\\ -{x_5}^{\&prime;}& -{x_6}^{\&prime;}& -{x_7}^{\&prime;}& -{x_8}^{\&prime;}& {x_1}^{\&prime;}& {x_2}^{\&prime;}& {x_3}^{\&prime;}& {x_4}^{\&prime;}\\ -{x_6}^{\&prime;}& {x_5}^{\&prime;}& -{x_8}^{\&prime;}& {x_7}^{\&prime;}& -{x_2}^{\&prime;}& {x_1}^{\&prime;}& -{x_4}^{\&prime;}& {x_3}^{\&prime;}\\ -{x_7}^{\&prime;}& {x_8}^{\&prime;}& {x_5}^{\&prime;}& -{x_6}^{\&prime;}& -{x_3}^{\&prime;}& {x_4}^{\&prime;}& {x_1}^{\&prime;}& {x_2}^{\&prime;}\\ -{x_8}^{\&prime;}& -{x_7}^{\&prime;}& {x_6}^{\&prime;}& {x_5}^{\&prime;}& -{x_4}^{\&prime;}& -{x_3}^{\&prime;}& -{x_2}^{\&prime;}& {x_1}^{\&prime;}\end{array}\right]---\left(6\right)$

X wherein ₁' be real number greater than 0, x ₂', x ₃', x ₄', x ₅', x ₆', x ₇', x ₈' be real number;

Then, the Generalized Complex Variable orthogonal matrix S of structure real matrix X correspondence ₈:

$S_8=\left[\begin{array}{c}X+j{X}^{\&prime;}\\ X-j{X}^{\&prime;}\end{array}\right]---\left(7\right)$

Complex matrix S ₈Have following character:

$S_8^H\&CenterDot;S_8=\mathrm{\&rho;}\&CenterDot;I_8---\left(8\right)$

Wherein, the conjugate transpose of subscript " H " representing matrix, I ₈The unit square formation on one 8 rank of expression, ρ represents a constant, the size of ρ is:

$\mathrm{\&rho;}=2({\left|x_1\right|}^2+{\left|x_2\right|}^2+\&CenterDot;\&CenterDot;\&CenterDot;+{\left|x_8\right|}^2+{\left|{x_1}^{\&prime;}\right|}^2+{\left|{x_2}^{\&prime;}\right|}^2+\&CenterDot;\&CenterDot;\&CenterDot;+{\left|{x_8}^{\&prime;}\right|}^2)=2\underset{i=1}{\overset{8}{\mathrm{\&Sigma;}}}({\left|x_i\right|}^2+{\left|{x_i}^{\&prime;}\right|}^2)---\left(9\right)$

$S_8=\left[\begin{array}{cccccccc}{s}_1& s_2& s_3& s_4& s_5& s_6& s_7& s_8\\ -s_2& s_1& s_4& -s_3& s_6& -s_5& -s_8& s_7\\ -s_3& -s_4& s_1& s_2& s_7& s_8& -s_5& -s_6\\ -s_4& s_3& -s_2& s_1& s_8& -s_7& s_6& -s_5\\ -s_5& -s_6& -s_7& -s_8& s_1& s_2& s_3& s_4\\ -s_6& s_5& -s_8& s_7& -s_2& s_1& -s_4& s_3\\ -s_7& s_8& s_5& -s_6& -s_3& s_4& s_1& -s_2\\ -s_8& -s_7& s_6& s_5& -s_4& -s_3& s_2& s_1\\ s_1^{*}& s_2^{*}& s_3^{*}& s_4^{*}& s_5^{*}& s_6^{*}& s_7^{*}& s_8^{*}\\ -s_2^{*}& s_1^{*}& s_4^{*}& -s_3^{*}& s_6^{*}& -s_5^{*}& -s_8^{*}& s_7^{*}\\ -s_3^{*}& -s_4^{*}& s_1^{*}& s_2^{*}& s_7^{*}& s_8^{*}& -s_5^{*}& -s_6^{*}\\ -s_4^{*}& s_3^{*}& -s_2^{*}& s_1^{*}& s_8^{*}& -s_7^{*}& s_6^{*}& -s_5^{*}\\ -s_5^{*}& -s_6^{*}& -s_7^{*}& -s_8^{*}& s_1^{*}& s_2^{*}& s_3^{*}& s_4^{*}\\ -s_6^{*}& s_5^{*}& -s_8^{*}& s_7^{*}& -s_2^{*}& s_1^{*}& -s_4^{*}& s_3^{*}\\ -s_7^{*}& s_8^{*}& s_5^{*}& -s_6^{*}& -s_3^{*}& s_4^{*}& s_1^{*}& -s_2^{*}\\ -s_8^{*}& -s_7^{*}& s_6^{*}& s_5^{*}& -s_4^{*}& -s_3^{*}& s_2^{*}& s_1^{*}\end{array}\right]---\left(10\right)$

S wherein ₁, s ₂... s ₈Be the complex channel symbol, and s _i=x _i+ jx _iI=1,2...8;

Broad sense complex orthogonal matrix S ₈Be and comprise that 8 transmit antennas, 4 reception antennas (are called for short: the Space-Time Block Coding of mimo system 8 * 4);

In like manner, the Space-Time Block Coding method of the mimo system of structure 6 * 4 (i.e. 6 transmit antennas, 4 reception antennas) is S ₈The two row deletions of matrix back just can obtain 6 * 4 encoder matrix S ₆:

$S_6=\left[\begin{array}{cccccc}{s}_1& s_2& s_3& s_4& s_5& s_6\\ -s_2& s_1& s_4& -s_3& s_6& -s_5\\ -s_3& -s_4& s_1& s_2& s_7& s_8\\ -s_4& s_3& -s_2& s_1& s_8& -s_7\\ -s_5& -s_6& -s_7& -s_8& s_1& s_2\\ -s_6& s_5& -s_8& s_7& -s_2& s_1\\ -s_7& s_8& s_5& -s_6& -s_3& s_4\\ -s_8& -s_7& s_6& s_5& -s_4& -s_3\\ s_1^{*}& s_2^{*}& s_3^{*}& s_4^{*}& s_5^{*}& s_6^{*}\\ -s_2^{*}& s_1^{*}& s_4^{*}& -s_3^{*}& s_6^{*}& -s_5^{*}\\ {-s}_3^{*}& -s_4^{*}& s_1^{*}& s_2^{*}& s_7^{*}& s_8^{*}\\ -s_4^{*}& s_3^{*}& -s_2^{*}& s_1^{*}& s_8^{*}& -s_7^{*}\\ -s_5^{*}& -s_6^{*}& -s_7^{*}& -s_8^{*}& s_1^{*}& s_2^{*}\\ -s_6^{*}& s_5^{*}& -s_8^{*}& s_7^{*}& -s_2^{*}& s_1^{*}\\ -s_7^{*}& s_8^{*}& s_5^{*}& -s_6^{*}& -s_3^{*}& s_4^{*}\\ -s_8^{*}& -s_7^{*}& s_6^{*}& s_5^{*}& -s_4^{*}& -s_3^{*}\end{array}\right]---\left(11\right)$

Through after the above-mentioned steps, just can construct the Space-Time Block Coding of the mimo system that is applicable to six of outfits or eight transmitting antennas, four reception antennas.

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