Received Power Vs Distance

Hi Everyone;

My MATLAB code result in the received power increases with distance as shown in the figure in spite I use Friis formula. Where is my mistake.

Pr=Pt*Gt*Gr*lambda^2./16*pi^2.*(Z).^2; %Friis Formula

Answer 1

[Alan Stevens]

If Z is distance then you should probably have

Pr=Pt*Gt*Gr*lambda^2./(16*pi^2.*Z.^2);

Note the position of the parentheses. In your version Z is on the numerator.

[A.J.M]

Thanks, Mr.Alan Stevens for your reply. I think the problem was solved as shown in the new figure. Are you mean that the problem was the parentheses? Is the formula correct for the received power?

Thanks a lot

[Alan Stevens]

Yes, the problem was the positioning of the parentheses.

I've no idea if the formula is correct in total, but power almost certainly decreases with distance away from the source.

[A.J.M]

Thanks a lot Mr.Alan Stevens.