7.20. Six hundred voice channels, each having a bandwidth of 4 kHz, arc multiplexed using USSB subcarrier modulation and the multiplexed signal frequency modulates a carrier. The lowest SSB carrier frequency is 10 kHz and the subcarriers are spaced 4 kHz apart. Assume that each voice signal has the same average power. The channel at 10 kHz has an output signal-to-noise ratio of 60 dB. (a) If (S/N) <30 dB is not acceptable, how many channels in the system are usable? (Assume white noise at the FM receiver input.) (b) If the FDM signal phase modulates the carrier, calculate (S/N)a for any channel assuming that the transmitted signal power and noise psd are the same as in the FM case.

7.20. Six hundred voice channels, each having a bandwidth of 4 kHz, arc multiplexed using USSB subcarrier modulation and the multiplexed signal frequency modulates a carrier. The lowest SSB carrier frequency is 10 kHz and the subcarriers are spaced 4 kHz apart. Assume that each voice signal has the same average power. The channel at 10 kHz has an output signal-to-noise ratio of 60 dB. (a) If (S/N) <30 dB is not acceptable, how many channels in the system are usable? (Assume white noise at the FM receiver input.) (b) If the FDM signal phase modulates the carrier, calculate (S/N)a for any channel assuming that the transmitted signal power and noise psd are the same as in the FM case.

Introductory Circuit Analysis (13th Edition)

13th Edition

ISBN:9780133923605

Author:Robert L. Boylestad

Publisher:Robert L. Boylestad

Chapter1: Introduction

Section: Chapter Questions

Problem 1P: Visit your local library (at school or home) and describe the extent to which it provides literature...

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