cdma的MATLAB仿真源程序

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

% This function pertains to the addition of AWGN with mean zero and % parameter 'variance' to an input signal. %

% AUTHOR: Wenbin Luo % DATE : 04/12/01 % % SYNOPSIS: y = awgn(x,var) % x ---> input signal % var ---> variance

% y ---> y = x + AWGN

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

function y = awgn(x,var) w = randn(1,length(x)); w = w - mean(w)*ones(size(w)); w = sqrt(var)*(w / std(w)); x = x(:); w = w(:); y = x + w;

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

% This function does the DS-SS modulation %

% AUTHOR: Wenbin Luo % DATE : 04/28/01 % % SYNOPSIS: y = ds_mod(c,x) % c ---> user code (column vector) % x ---> input signal (row vector)

% y ---> tmp = c*x, y = tmp(:) (ds-ss modulated signal, column vector)

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

function y = ds_mod(c,x) tmp = c*x; y = tmp(:);

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

% This function generates random +1/-1 sequence with independent identically % distributed symbols %

% AUTHOR: Wenbin Luo

% DATE : 04/28/01 % % SYNOPSIS: x = bingen(L)

% L ---> number of random symbols

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

function x = bingen(L)

%generate L symbols randomly