Q. Two stations (using identical antennas, with diameters of 50λ and aperture ef?ciencies of 0.6 at 35 GHz) are separated by 30 km. With negligible antenna losses, antenna connection-path losses are Lt = Lr = 1.33 at a physical temperature of 285 K, while the antenna temperature is 85 K. The receiver at either station hasGa(f 0)=107, TR = 250 K, and BN = 12 MHz. The rain attenuation and clear-air attenuation are given to be 3.9 dB/km and 0.072 dB/km, respectively. Determine:

(a) The required output power to guarantee a system signal-to-noise power ratio of 45 dB when heavy rain falls over a distance of 6 km.

(b) The available noise power occurring at the receiver output.

(c) The output signal power occurring with and without rain, when the transmitted power found in part (a) is used.