%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
            %   對M=4的PSK通信系統進行蒙特卡羅仿真   %
            %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
echo on
SNRindB1=0:2:10;
SNRindB2=0:0.1:10;
for i=1:length (SNRindB1),
   [pb , ps]=cm_sm32 (SNRindB1 (i));         %仿真比特和符號誤碼率
   smld_bit_err_prb (i)=pb;
   smld_symbol_err_prb (i)=ps;
end;
for i=1:length (SNRindB2),
   SNR=exp(SNRindB2(i)*log(10)/10);        %信噪比
   theo_err_prb(i)=Qfunct(sqrt(2*SNR));    %理論比特誤碼率
end;
 %%%%%%%隨后繪圖曲線%%%%%%%
semilogy (SNRindB1,smld_bit_err_prb,'*');
hold
semilogy (SNRindB1,smld_symbol_err_prb,'O');
semilogy (SNRindB2,theo_err_prb);
grid
xlabel('Eb/No in dB')
ylabel('error probability')
title('4PSK通信系統的蒙特卡洛仿真')
gtext('（注：“—”理論誤碼率；“*”誤比特率；“o”誤符號率）')