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% ***********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;