how to code selective combining for releight fading

h(k)=sqrt(1/2)*(randn+j*randn); n(k)=sqrt(N0/2)*(randn+j*randn); r(k)=h(k)*s+n(k); end [T1 T2]=max(r(k)); D=r(T1)*exp(-j*angle(T1)); b_hat=sign(real(D)); if b_hat~=b; err_cnt=err_cnt+1; end sym_cnt=sym_cnt+1; I am using this code but it is giving an error in a bold portion....Can u please solve my problem?

Answer 1

[Maaz Salman]

clear EbN0dB_vector=0:3:15; Eb=1; L=3; for snr_i=1:length(EbN0dB_vector) EbN0dB=EbN0dB_vector(snr_i); EbN0=10.^(EbN0dB/10); N0=Eb/EbN0; sym_cnt=0; err_cnt=0; while err_cnt<100 % If you increase err_cnt (currently 100), the accuracy increases and time also increase. b=sign(rand-0.5); %BPSK symbol{1,-1} s=sqrt(Eb/L)*b; for k=1:L h(k)=sqrt(1/2)*(randn+j*randn); n(k)=sqrt(N0/2)*(randn+j*randn); r(k)=h(k)*s+n(k); end [T1 T2]=max(r(k));% Refer to (25.9). To see how to use max( ), execute ‘>>help max’ in the command window. D=r(T1)*exp(-j*angle(T1));%Refer to (25.9). b_hat=sign(real(D)); if b_hat~=b; err_cnt=err_cnt+1; end sym_cnt=sym_cnt+1; end BER(snr_i)=err_cnt/sym_cnt; end figure semilogy(EbN0dB_vector, BER) xlabel('E_b/N_0 [dB]') ylabel('BER') grid Whole code is given above

[Maaz Salman]

Error is showing in the portion: [T1 T2]=max(r(k));d window. D=r(T1)*exp(-j*angle(T1)); Can you please solve this problem?