Galois Field with RS code Issue

Hi every one I am working on Reed Solomon Code I want to compare its ber performance with uncoded BPSK may problem is RS codes works under GF so i am asking for your help in generating the AWGN and then return the result to 0/1 by a threshold all this have to be done UNDER GF my program is shown below clc; close all; clear all; m=8; n=255;k=223; l=10;nn=1; for snr=0:10 error(nn)=0; for i=1:l x=randint(1,223); mes=gf(x,m); code = rsenc(mes,n,k); decoded=rsdec(code,n,k); if (decoded~=mes) error(nn)=error(nn)+1 end end BER(nn)=error(nn)/(k*l) nn=nn+1;

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