two ray channel

% TWO RAY CHANNEL

lambda = 0.3;

ht100 = 100;

ht30 = 30;

ht2 = 2;

hr = 2;

axis = [];

p100 = [];

p30 = [];

p2 = [];

pfsl = [];

for i = 1000:5000

    d = 10^(i/1000);

    axis = [axis d];

    fspower = (lambda/(4*3.1415*d))^2;

    power100 = fspower * 4 * (sin(2*3.1415*hr*ht100/(lambda*d)))^2;

    power30 = fspower * 4 * (sin(2*3.1415*hr*ht30/(lambda*d)))^2;

    power2 = fspower * 4 * (sin(2*3.1415*hr*ht2/(lambda*d)))^2;

    p100 = [p100, 10*log10(power100)];

    p30 = [p30, 10*log10(power30)];

    p2 = [p2, 10*log10(power2)];

    pfsl = [pfsl, 10*log10(fspower)];

end

figure;

semilogx(axis, p100, 'g-', axis, p30, 'b-', axis, p2, 'r-', axis, pfsl,'y-');

xlabel('distance in m');

ylabel('pathloss');

text(1000, -66, 'blue : ht=30m', 'FontSize', 12);

text(1000, -74, 'red : ht=2m', 'FontSize', 12);

text(1000, -58, 'green : ht=100m', 'FontSize', 12);

text(1000, -50, 'yellow: free space', 'FontSize', 12);

text(50, -180, 'lambda = 0.30 m', 'FontSize', 12);

text(50, -190, 'hr = 2 m', 'FontSize', 12);

grid on;