clear all
ht=10;hr=2;
c=3e8;f=1e9;lambda=c/f;
R=-1;
d=1:0.5:10000;
d1=sqrt(d.^2+(ht-hr)^2);
d2=sqrt(d.^2+(ht+hr)^2);
a1=exp(j*2*pi.*d1/lambda)./d1;
a2=R*exp(j*2*pi.*d2/lambda)./d2;
a=abs(a1+a2);
ld=log10(d);la=log10(a);
figure (4)
plot(ld,la);
xlabel('log10(distance)')
ylabel('log10(magnitude)')
title( 'two ray model')