Help me path loss exponent in my simulation code

[robintane]

Dear

I am trying to simulate SISO communication with many relay serial.

[B] y1 = h1.*x + n1;   %Noise addition
    r1=y1./h1;         %Receiver[/B]

Please tell me how should I include path loss exponent in my simulation code? ( Path loss depend on dimension betwen Source and Relay)

Thank you very much