HELP NEEDED for em solvers.

can anyone tell which is best software for simulating an electromagnetic model

1 transmitter and 1 receiver are located in free space of 1000m distance..
and how to measure the received power, if transmitted power is 1 watt.

please help me..

What is the frequency...also if you know your gain of transmitter and gain of receiver then you should be able to determine power received quite easily if propagation is just in un impeded free space via Friis equation.

have fun

I agree. An EM solver is probably not the right solution for your problem. This sounds like a radio link and transmitted power problem, so use the Friis transmission equation.

This website gives a nice walk-thru from the fundamental equation, and shows a step-by-step process of adding in other known variables for your system.
Friis Transmission Formula - (aka Friis Transmission Equation)