channel.m

这是一个TD-SCDMA系统的RAKE接收模型

function out=channel(in)
    
    global sys_consts;
    
    L = size(in,2);
        
    switch sys_consts.channel
        case {'awgn'}
            
        case {'case1'}
            
            L1=L+sys_consts.Lh-1;                  % 经过信道后长度（加上信道传输延迟）
            out=zeros(1,L1);                                        % 置接收信号长度和令初始值为0
            for k = 1:sys_consts.Lh
                out(1,k:L+k-1) = out(1,k:L+k-1)+in*sys_consts.h(k);
            end
                 
        case {'case2'}
                    
        case {'case3'}
            
            
    end
    
    EbN0 = -5;
     en = 10^(-EbN0/10);                                 % convert Eb/N0 from unit db to normal numbers
     sigma = sqrt(en/2);

    
    
    out = out + sigma*(randint(1,size(out,2))+j*randint(1,size(out,2)));
    return;