cdma的MATLAB仿真源程序

y = sqrt(p)*y;

-d AWGN to signal y = awgn(y,1);

%DS-SS demodulate symbols with user code x_de = ds_demod(c(:),y);

Tcision

x_de(find(x_de < 0)) = -1; x_de(find(x_de >=0)) = 1;

Tcode error-correcting code x_de(find(x_de < 0)) = 0;

x_de = decode(x_de,enc_N,enc_K,'bch'); x_de = x_de';

x_de(find(x_de == 0)) = -1;

%------------------------------------- Pe = length(find(x_org - x_de))/x_num; Plot_Pe = [Plot_Pe Pe]; end %end for EbNo

%--------------------------------------------- %return;

%---------------------------------------------

%display the calculated Pd and Pfa Plot_Pe

%plot Pe versus Eb/No

semilogy(plot_EbNo,Plot_Pe,'bo-') xlabel('Eb/No (dB)') ylabel('BER')

s=sprintf('BER versus Eb/No with binary BCH code in the AWGN channel'); title(s);

%********************************************************************** % This program computes the average BER of a DS-SS/BPSK %

communication system with binary BCH code in the AWGN channel

%

% AUTHOR: Wenbin Luo % DATE : 04/28/01 % % %

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

%function Plot_Pe = final11_extra() clear all;

%close all;

format long;

%set up the threshold Vt Vt = 0;

Plot_Pe = []; N = 16; x_num = 2500; plot_EbNo = -20:2:10; for EbNo = -20:2:10,

%convert back from dB Eb_No = EbNo; ? Eb_No = 10.^(Eb_No/10); %assume No = 2; No = 2;

Eb = No * Eb_No; êlculate power p Tc = 1; Ts = N * Tc; p = Eb / Ts;

%generate BPSK symbols randomly with value +1 or -1

x = bingen(x_num); x_org = x;

-ds error-correcting code

enc_N = 15; enc_K = 5; %7/4 or 15/5 x(find(x < 0)) = 0;

x = encode(x,enc_N,enc_K,'bch'); x = x';

x(find(x == 0)) = -1;

%DS-SS modulate symbols with user code c = bingen(N); y = ds_mod(c(:),x);

%scale by appropriate power factor y = sqrt(p)*y;

-d AWGN to signal y = awgn(y,1);

%DS-SS demodulate symbols with user code x_de = ds_demod(c(:),y);

Tcision

x_de(find(x_de < 0)) = -1;

x_de(find(x_de >=0)) = 1;

Tcode error-correcting code x_de(find(x_de < 0)) = 0;

x_de = decode(x_de,enc_N,enc_K,'bch'); x_de = x_de';

x_de(find(x_de == 0)) = -1;

%------------------------------------- Pe = length(find(x_org - x_de))/x_num; Plot_Pe = [Plot_Pe Pe]; end %end for EbNo

%--------------------------------------------- %return;

%---------------------------------------------

%display the calculated Pd and Pfa Plot_Pe

%plot Pe versus Eb/No

semilogy(plot_EbNo,Plot_Pe,'bo-') xlabel('Eb/No (dB)') ylabel('BER')

s=sprintf('BER versus Eb/No with binary BCH code in the AWGN channel');