(Solved): 4. A radio link has 20 Watt transmitter connected to an antenna of 0.5 m2 effective aperture at 9 ...

4. A radio link has 20 Watt transmitter connected to an antenna of 0.5 m2 effective aperture at 9 GHz. The receiving antenna has an effective aperture 2.0 m2 and is located 20 km line of sight from the transmitting antenna. Assuming the antennas have efficiencies equal to unity, find the power delivered to the receiver.