matlab.rar_数学计算_matlab_

%% Alamouti space time codes also known as Orthogonal Codes %% Space Time Coding %% Chapter # 3, Topic # 3.2 close all; clear all; clc; M=4; %% modulation scheme m=log2(M); %% No of information bits x=round(rand(1,m)); %% information v=2*x-1; %% BPSK Modulation X=[v(1,1) -conj(v(1,2));v(1,2) conj(v(1,1))]; %% Alamouti Encoder x1=X(1,:); %% first Transmitt symbols x2=X(2,:); %% 2nd Transmitt Symbols %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% %%%%%%%% Check Two transmitt antennas signal are orthogonal %%%%%%%%%%%%%%% orthogonal=x1*x2'; %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% %%%%%%%% Check Code Matrix Property %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% codematrix=X*X'; h1=0.7; %% Flat Fading Coefficient h2=0.6; %% Flat Fading Coefficient H=[h1;h2]; %% Fading Matrix n1=rand(1,1); %% Random Noise n2=rand(1,1); %% Random Noise N=[n1;n2]; %% Noise Matrix R=X'*H+N; %% Recieve Signal x1_dec=conj(h1)*R(1,1)+h2*conj(R(2,1)); %% Decision Matric x2_dec=conj(h2)*R(1,1)-h1*conj(R(2,1)); %% Decision Matric X_dec=[x1_dec; x2_dec]; %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% %%%%%%%%%%%%% Estimating information using MAP %%%%%%%%%%%%%%%%%%%%%%%%%%%% for i=1:length(x) if X_dec(i)>0; x_est(i)=1; else x_est(i)=0; end end %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% % 03009785929