tufa_jiaozhi_pe.m

GSM信道编码设计

function[sig_err_rate]=tufa_jiaozhi_pe(snr_in_dB)
%噪声功率
E=1;
snr=10^(snr_in_dB/10);
sgma=sqrt((E/snr)/2);
%桢个数
N=10;
%突发间隔
N_Interval=80;
%突发长度
N_Length=5;
%信息序列
in=[round(rand(N,185)),zeros(N,4),round(rand(N,78))];
signal=reshape(in',1,267*N);
%编码
for n=0:(N-1)
    %卷积编码
    neibian_sig(1:456)=nei_bianma(in(n+1,:));
   %交织前合成
   C([1:456]+n*456)=neibian_sig(1:456);
end;
%交织
u=jiaozhi(C);
%%%%%%%%%%%%%%%%%%%%%
%经信道加高斯燥声
u=2*u-1;
u=sign(u+sgma*randn(size(u))+eps);
u=(u+1)/2;
%加突发噪声
Noise=BurstNoise(N_Interval,N_Length,length(u));
u=mod(u+Noise,2);
%%%%%%%%%%%%%%%%%%%%%
%反交织
D=fanjiaozhi(u);
%解码
for n=0:(N-1)
	%分离桢
   neiyi_sig=D([1:456]+n*456);
    %内编码解码
	newsignal([1:267]+n*267)=nei_yima(neiyi_sig);
end;

   sig_err_rate=(length(find(signal~=newsignal)))/length(signal);