分集+均衡作业

《matlab分集+均衡》实验报告

姓 名 李聪 学 号 11211060 指导教师 姚冬萍 时 间 2014年5月25日

分集matlab作业

现给出最大比合并（MRC）、等增益合并（EGC）和选择性合并的分集合并程序，理解各程序，完成以下习题。将程序运行结果及各题目的解答写入word中：

1. 用matlab分别运行“BPSKMRC.m”、“BPSKEGC.m”以及“BPSKSEL.m” （a）在程序中标注“注释”处加上注释（英文或中文）

MRC

% bpsk.m

% Simulation program to realize BPSK transmission system

%******************** Preparation part ********************** nd = 10000; % Number of symbols that simulates in each loop snr_in_dB=[0:15] ;

ber=zeros(1,length(snr_in_dB));

for snr_num=1:length(snr_in_dB)

SNR=exp(snr_in_dB(snr_num)*log(10)/10);

%******************** START CALCULATION ********************* nloop=100; % Number of simulation loops noe = 0; % Number of error data

nod = 0; % Number of transmitted data

for iii=1:nloop

%******************** Data generation ********************************

data1=rand(1,nd)>0.5; data2=2.*data1-1;

%****************** Attenuation Calculation ***************** %****************** rayleigh channel *****************

code_rate=1; E=1;

sigma=E/sqrt(2*SNR*code_rate);

n =[randn(1,nd) + j*randn(1,nd)];

h1 =1/sqrt(2)*[randn(1,nd) + j*randn(1,nd)]; % Rayleigh channel data41=data2.*h1+sigma.*n;

h11=conj(h1); %注释：根据测得的信号幅度相位得到各支路加权系数 data411 = data41.*h11; %注释：将各个支路信号调整为同相信号 %***************************************** n =[randn(1,nd) + j*randn(1,nd)];

h2 =1/sqrt(2)*[randn(1,nd) + j*randn(1,nd)]; % Rayleigh channel data42=data2.*h2+sigma.*n; h22=conj(h2);

data422 =data42.*h22;

%*****************************************

data4=data411+data422;% 注释：各个已调为同相信号支路作相关电压的叠加

%******************** BPSK Demodulation *********************

demodata1=data4 > 0;

%******************** Bit Error Rate (BER) ******************

noe2=sum(abs(data1-demodata1)); nod2=length(data1); noe=noe+noe2; nod=nod+nod2;

end

%********************** Output result ***************************

ber(snr_num) = noe/nod

end;

%******************** end of file *************************** figure;

semilogy(snr_in_dB,ber,'O-'); hold on

semilogy(snr_in_dB,0.5*erfc(sqrt(2*10.^(snr_in_dB/10))/sqrt(2)),'+-'); hold on

semilogy(snr_in_dB,0.5.*(1-sqrt((10.^(snr_in_dB/10))./(10.^(snr_i

n_dB/10)+1))),'-'); ylabel('BER');

xlabel('E_b/N_0 [dB]');

legend('simulation BPSK MRC L=2','theory gngauss BPSK','theory reyleigh' );

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

EGC

% bpsk.m

% Simulation program to realize BPSK transmission system

%******************** Preparation part ********************** nd = 10000; % Number of symbols that simulates in each loop snr_in_dB=[0:15] ;

ber=zeros(1,length(snr_in_dB));

for snr_num=1:length(snr_in_dB)

SNR=exp(snr_in_dB(snr_num)*log(10)/10);

%******************** START CALCULATION ********************* nloop=100; % Number of simulation loops noe = 0; % Number of error data

nod = 0; % Number of transmitted data

for iii=1:nloop

%******************** Data generation ******************************** data1=rand(1,nd)>0.5; data2=2.*data1-1;

%****************** Attenuation Calculation ***************** %****************** rayleigh channel *****************

code_rate=1; E=1;

sigma=E/sqrt(2*SNR*code_rate); n =[randn(1,nd) + j*randn(1,nd)];

h1 =1/sqrt(2)*[randn(1,nd) + j*randn(1,nd)]; % Rayleigh channel data41=data2.*h1+sigma.*n;

h11=conj(h1)./abs(h1); %注释：得到各个支路等增益合并的加权系数 data411 = data41.*h11; %注释：将支路信号调整为同相信号