div.m

GSM信道编码设计

ux=zeros(1,41);
ux(1)=1;

%ux(x)=x^40

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%division circuit
%ccx(x)=uu(x)/g(x)
%%g(x)=x^40+x^26+x^23+x^17+x^3+1
uu=ux;

ccx=[];
gx_out=[];
gx_reg=zeros(1,40);
gx_gg=zeros(1,41);
gx_gg(41)=1;
gx_gg(27)=1;
gx_gg(24)=1;
gx_gg(18)=1;
gx_gg(4)=1;
gx_gg(1)=1;
for i=1:length(uu)
   feedback=gx_gg(41)*gx_reg(40);
   gx_out(i)=gx_reg(40);
   for j=40:-1:2
      gx_reg(j)=rem(gx_reg(j-1)+feedback*gx_gg(j),2);
   end
   gx_reg(1)=rem(uu(i)+feedback*gx_gg(1),2);
end

ccx=gx_out(41:length(uu));
gx_reg

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