16QAM仿真代码(matlab).doc

% 16QAM 系统仿真function ber_AWGN,ber_Ray = M16QAM()EbN0dB=1:3:30;EbN0dB1=1:10;N=4*100000;for ii=1:length(EbN0dB) sigma2(ii)=2.5/(2*4*(10(EbN0dB(ii)/10); sigma21(ii)=2.5/(2*4*(10(EbN0dB1(ii)/10); bits=randint(1,N); %调制 s=M16QAM_modulate(bits,length(bits(:); % Rayleign信道干扰 noise=sqrt(sigma2(ii)*( randn(1,N/4)+ 1i*randn(1,N/4) ); h= sqrt(0.5)*(randn(1,N/4) + 1i*randn(1,N/4) ); receiver=s.*h+noise; %Rayleign 衰减信道 % 高斯信道干扰 noise1=sqrt(sigma21(ii)*( randn(1,N/4)+ 1i*randn(1,N/4) ); receiver1=s+noise1; %高斯信道 % 信道均衡 receiver = receiver./h; %解调并计算误码率 Rayleign信道 demodata = M16QAM_demodulate( receiver,length(receiver(:) ); errCount=sum(abs(bits-demodata); ber_Ray(ii)=errCount/N; %解调并计算误码率 高斯信道 demodata = M16QAM_demodulate( receiver1,length(receiver1(:) ); errCount=sum(abs(bits-demodata); ber_AWGN(ii)=errCount/N;endend% 16QAM 调制function s = M16QAM_modulate( bits,N)ii=0; for i=1:4:N ii=ii+1; if bits(i)=0&bits(i+1)=0&bits(i+2)=0&bits(i+3)=0 s(ii)=sqrt(2)/2*exp(1i*pi/4); elseif bits(i)=1&bits(i+1)=0&bits(i+2)=0&bits(i+3)=0 s(ii)=sqrt(2)/2*exp(1i*3*pi/4); elseif bits(i)=1&bits(i+1)=0&bits(i+2)=1&bits(i+3)=0 s(ii)=sqrt(2)/2*exp(1i*5*pi/4); elseif bits(i)=0&bits(i+1)=0&bits(i+2)=1&bits(i+3)=0 s(ii)=sqrt(2)/2*exp(1i*7*pi/4); elseif bits(i)=0&bits(i+1)=1&bits(i+2)=0&bits(i+3)=0 s(ii)=sqrt(10)/2*exp(1i*atan(1/3); elseif bits(i)=0&bits(i+1)=0&bits(i+2)=0&bits(i+3)=1 s(ii)=sqrt(10)/2*exp(1i*atan(3); elseif bits(i)=1&bits(i+1)=0&bits(i+2)=0&bits(i+3)=1 s(ii)=sqrt(10)/2*exp(1i*(atan(1/3)+pi/2); elseif bits(i)=1&bits(i+1)=1&bits(i+2)=0&bits(i+3)=0 s(ii)=sqrt(10)/2*exp(1i*(pi-atan(1/3); elseif bits(i)=1&bits(i+1)=1&bits(i+2)=1&bits(i+3)=0 s(ii)=sqrt(10)/2*exp(1i*(atan(1/3)+pi); elseif bits(i)=1&bits(i+1)=0&bits(i+2)=1&bits(i+3)=1 s(ii)=sqrt(10)/2*exp(1i*(3*pi/2-atan(1/3); elseif bits(i)=0&bits(i+1)=0&bits(i+2)=1&bits(i+3)=1 s(ii)=sqrt(10)/2*exp(1i*(atan(1/3)+3*pi/2); elseif bits(i)=0&bits(i+1)=1&bits(i+2)=1&bits(i+3)=0 s(ii)=sqrt(10)/2*exp(1i*(2*pi-atan(1/3); elseif bits(i)=0&bits(i+1)=1&bits(i+2)=0&bits(i+3)=1 s(ii)=sqrt(2)*3/2*exp(1i*pi/4); elseif bits(i)=1&bits(i+1)=1&bits(i+2)=0&bits(i+3)=1 s(ii)=sqrt(2)*3/2*exp(1i*3*pi/4); elseif bits(i)=1&bits(i+1)=1&bits(i+2)=1&bits(i+3)=1 s(ii)=sqrt(2)*3/2*exp(1i*5*pi/4); elseif bits(i)=0&bits(i+1)=1&bits(i+2)=1&bits(i+3)=1 s(ii)=sqrt(2)*3/2*exp(1i*7*pi/4); end endend% 16 QAM 解调function demodata = M16QAM_demodulate( receiver ,N)A=0 1 0 1; -1 0 0 1;-1 0 -1 0;0 1 -1 0; 1 inf 0 1;0 1 1 inf;-1 0 1 inf;-inf -1 0 1; -inf -1 -1 0;-1 0 -inf -1;0 1 -inf -1;1 inf -1 0; 1 inf 1 inf;-inf -1 1 inf;-inf -1 -inf -1;1 inf -inf -1;for k=1:N if (real(receiver(k)=A(1,1)&(real(receiver(k)=A(1,3)&(imag(receiver(k)=A(2,1)&(real(receiver(k)=A(2,3)&(imag(receiver(k)=A(3,1)&(real(receiver(k)=A(3,3)&(imag(receiver(k)=A(4,1)&(real(receiver(k)=A(4,3)&(imag(receiver(k)=A(5,1)&(real(receiver(k)=A(5,3)&(imag(receiver(k)=A(6,1)&(real(receiver(k)=A(6,3)&(imag(receiver(k)=A(7,1)&(real(receiver(k)=A(7,3)&(imag(receiver(k)=A(8,1)&(real(receiver(k)=A(8,3)&(imag(receiver(k)=A(9,1)&(real(receiver(k)=A(9,3)&(imag(receiver(k)=A(10,1)&(real(receiver(k)=A(10,3)&(imag(receiver(k)=A(11,1)&(real(receiver(k)=A(11,3)&(imag(receiver(k)=A(12,1)&(real(receiver(k)=A(12,3)&(imag(receiver(k)=A(13,1)&(real(receiver(k)=A(13,3)&(imag(receiver(k)=A(14,1)&(real(receiver(k)=A(14,3)&(imag(receiver(k)=A(15,1)&(real(recei