Electronic Communication Systems 2nd Edition by Roy Blake

Exercise 41

A microwave digital radio system requires an E h /N 0 ratio of 12 dB for a satisfactorily low error rate. If it operates at 90.524 Mb/s using a bandwidth of 30 MHz, what transmitter power will be required for a communications range of 35 km The antennas at each end of the path have 20 dB gain, and the sky noise temperature is 120 K. The receiver has a noise temperature of 65 K. Ignore losses in the feed-lines. The carrier frequency is 6.5 GHz.