Consider a point-to-point radio link between two highly directional antennas in a stationary environment. The antennas have antenna gains of 30 dB, distance attenuation is 150 dB, and the receiver has a noise figure of 7 dB. The symbol rate is 20 Msymb/s and Nyquist signaling is used. It can be assume that the radio link can be treated as an AWGN channel without fading. How much transmit power is required (disregarding power losses at transmitter and receiver ends) for a maximum BER of 10-5, when using:
a) Coherently detected BPSK
b) Coherently detected FSK
c) Differentially detected BPSK
d) Non-Coherently detected FSK