amit
Posts:
2
Registered:
11/21/12


cognitive radio, energy detection
Posted:
Nov 21, 2012 9:51 AM


hi, im new to matlab and not used it before and any help, i will be really thankful, im trying to get a graph of PF vs PD this is my code, but something is wrong, especially for the outputs of y4, im not really sure anymore.
%monte carlo simulation function [y1,y2,y3,y4]= ed(SNRL,SNRS,SNRH,n) %ed is the energy detection g1= SNRL:SNRS:SNRH; g=10.^(g1/10); beta=0.01; % is the probability of flase alarm
pf1=zeros(1,length(g)); pd1=zeros(1,length(g)); pf2=zeros(1,length(g)); pd2=zeros(1,length(g));
for i=1 : length(g) y0 = randn(n,1000000); y1= randn(n,1000000)*sqrt(g(i))+y0; Tgam = gaminv(1beta,n/2,2/n*(1+g(i))); %threshold pf1(i)= gamcdf(Tgam,n/2,2/n*(1+g(i))) pd1 (i) = gamcdf(Tgam,n/2,2/n); % prob of detection pf2(i)= length (find(sum(y1.^2)/n<Tgam))/1000000; pd2 (i) = length (find(sum(y0.^2)/n<Tgam))/1000000; end y1=pf1; y2=pd1; y3=pf2; y4=pd2;

