Calculate power received?

How would I find the power received from a 20-W transmitter, 22,000 mi from earth, if the receiving antenna has an effective area of 1600 mi^2.

Assuming an omnidirectional antenna at the transmitter, the 20-W power at the distance 22000 mi will be spread over the area of S=4*pi*(22000^2)
You receive the part of this power that reaches your antenna, so this part of energy will be 1600/S.

You may convert it to power units by yourself.

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Assuming an omnidirectional antenna at the transmitter, the 20-W power at the distance 22000 mi will be spread over the area of S=4*pi*(22000^2)
You receive the part of this power that reaches your antenna, so this part of energy will be 1600/S.

You may convert it to power units by yourself.

a receiving antenna with a 1600 square mile aperture.... thats nutty

Have Fun

Use the free software SMWLink:

http://www.smw.se/SMWLink.htm

Nothing nutty 'cause this is not the outer dimensions itself. He may be using long waves...

However... I've just read that it is always less than dimension. So it is funny indeed.

You probably can use the effective area to calculate the gain
http://en.wikipedia.org/wiki/Antenna_aperture
and then use Friis transmission equation
http://en.wikipedia.org/wiki/Friis_t...ssion_equation
to determine the received power.