An ideal voice-band telephone line channel has a band-pass frequency-response characteristic spanning the frequency range 600–3000 Hz.
a. Design an M = 4 PSK (quadrature PSK or QPSK) system for transmitting data at a rate of 2400 bits/s and a carrier frequency fc = 1800 Hz. For spectral shaping, use a raised cosine frequency-response characteristic. Sketch a block diagram of the system and describe the functional operation of each block. b. Repeat (a) for a bit rate R = 4800 bits/s and a 8-QAM signal.