A cellular base station is to be connected to its Mobile Telephone Switching Office located 5 km away. Two possibilities are to be evaluated:
(1) a radio link operating at 28 GHz, with Gt = Gr = 25 dB, and
(2) a wired link using coaxial line having an attenuation of 0.05 dB/m, with four 30 dB repeater amplifiers along the line. If the minimum required received power level for both cases is the same, which option will require the smallest transmit power?