I have Implemented this detector in AWGN channel in Matlab but I am getting vague results. As its performance doesn't vary with change in SNR. Its a very strange result for me. I don't know what mistake I am doing in it. I am attaching my codes please have look and comment. Here I am finding cyclostationary feature of signal for its detection. Firstly I tried to Out FFT of a signal then shift its frequency by +alpha of tranform and -alpha to its conjugate. Then I multiplied both to taken sum of all. Thats how all theory explain about cyclostationary feature detection I will very grateful if somebody can help me in this.
function S=cyclio_stat_TestStatics(x,N)
lx=length(x);
X=zeros(2*N+1);
Y=zeros(2*N+1);
Ts=1/N;
for f=-N:N
d=exp(-j*2*pi*f*(0:lx-1)*Ts);
xf=x.*d;
n_r=lx:-1:1;
X(f+N+1)=sum(xf(n_r));
Y(f+N+1)=conj(sum(xf(n_r)));
end
alpha=10;
f=5;
f1=f+floor(alpha/2)+(floor(-((N-1)/2)):floor((N-1)/2));
f2=f-floor(alpha/2)+(floor(-((N-1)/2)):floor((N-1)/2));
S=sum(X(f1+N+1).*Y(f2+N+1))/N;
S=abs(S)/lx;
Can you share your reference, from which you've implemented the algorithm.
Imtiyaz,
It seems to me your loop is too short to catch the mean period, and your algorithm is not iterating to exploit the over sampling feature of incoming signal, which is dearly needed to get the mean signal variation aroud the exact signal period when using cyclostationary process.
Regards
@Ismail,
I didn't understand your explanation much but as far as i understand I want to tell that It is a function which i am calling in my main Code for iteration many times. And I think that will be enough to average signal variation.
@Mohammed
page no. 151
http://books.google.ee/books?id=JJXrpazX9FkC&pg=PA157&lpg=PA157&dq=cognitive+radio+spectrum+sharing+technology,+D+cabric+and+R.W+Brodersen&source=bl&ots=B-DAFxy5Ha&sig=zvV6fwCsLmvVXKfvwmBO7gckDEI&hl=en&sa=X&ei=3-ptVPvtNYOmyQTU8oHoBw&ved=0CDkQ6AEwAw#v=onepage&q=cognitive%20radio%20spectrum%20sharing%20technology%2C%20D%20cabric%20and%20R.W%20Brodersen&f=false
what output you are getting from the above code?what is the cyclic frequency you have taken?
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