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FM Radio RF Channels

a. Frequency modulation is regarded as a much preferred modulation method over DSB-LC AM for sound radio broadcasting. Give two reasons why FM is preferred over AM in sound radio broadcasting.

b. Do either or both of the reasons you gave in part (a) above also apply to a point to point voice link using frequency modulation?

c. Which parameter of an FM transmission determines whether it is wideband or narrow band?

d. First generation cellular telephones used FM with a 30 kHz RF channel. If the RF channel bandwidth had been 20 kHz, and the maximum audio frequency was kept at 3 kHz, which parameter of the FM modulation would have to be changed? What would be its new value?

e. If the narrower RF channel of 20 kHz were used as in part (d) above, how would the performance of the audio signal at the receiver be changed?

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See the attachment.

a. FM is considered superior to AM methods for broadcasting sound (indeed any information) for a number of reasons two of the main ones being

1. AM suffers from noise (static) due to unwanted amplitude variations added when transmitted through the atmosphere. This can result in noisy reception especially amplitude ...

Solution Summary

The solution discusses why FM is preferred over AM in sound radio broadcasting.