%-------------------------------------------
%  Compute Rician distribution
%  Pr[r<R] = 1 - Gen_Q(s/sigma, r/sigma, 1)
%  s= mean amplitude == 1
%  sigma is st. dev. of I or Q
%  s/sigma = 2*sqrt(2*K)
%-------------------------------------------

K = 13;    % dB
s = 1;
sigma_2x2 = s^2*10^(-K/10);
sigma = sqrt(sigma_2x2/2);

r= [.1 : 0.01 : 2]*s;

Pr = 1 - Gen_Q(s/sigma, r/sigma, 1);

semilogy(20*log10(r/s), Pr,'g');
grid