% ***********SIMULATION OF COEFFICIENTS OF RAYLEIGH FADING
CHANNEL************
%
% VEHICULAR SPEED, DOPPLER SHIFT
% FADING COEFFICIENTS
%********************************************************************** ********
Num_path=2000; % Number of paths
t=0.0001:10/Num_path:10; % Time range
f=150*10.^6; % Carrier frequency (150 Mhz, 900 Mhz) wc=2*pi*f;
vehicle_speed=100; % Speed of car[km/hrs]
v=vehicle_speed*5/18; % Receiver speed[m/hrs]
c=300*10^3; % Speed of light
wm=wc*(v/c); % Maximum shift
fm=wm/(2*pi); % Doppler shift
% SIMULATING ENSEMBLES OF SINUSOIDS
for i=1:Num_path
A(i)=(2*pi/Num_path)*i; %Azimuthal angles
wn(i)=wm*cos(A(i));
phi(i)=(pi*i)/(Num_path+1);
xc(i)=2*cos(wn(i)*t(i)).*cos(phi(i))+cos(wm*t(i));
xs(i)=2*cos(wn(i)*t(i)).*sin(phi(i));
T(i)=(1/(2*Num_path+1)^0.5).*(xc(i)+j*xs(i));% Complex envelope
end;
M=mean(abs(T)); % Mean
MdB=20*log10(M);
TdB=floor(20*log10(abs(T))); % Field [dB]
% PLOTTING THE HISTOGRAM
z1=hist(abs(T));
z=hist(TdB,9);
n=0;
for k=1:9
n=n+z(k);
end
for j=1:9
P(j)=z(j)/n;
end
f(1)=P(1);
for x=2:9
f(x)=f(x-1)+P(x);
F(10-x)=f(x);
end
plot(z1); % Distribution chart
title('Rayleigh distribution');
semilogy(t,abs(T)/max(abs(T)),'r') % Fading graphic
title('Received field');
ylabel('Received field intensity');
xlabel('time');
grid on;