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.