Effects of band-limiting the r.f. spectrum in a communication-satellite system employing wide-deviation frequency modulation

Reduction of the peak factor used in the design of frequency-modulation systems carrying multichannel telephony leads to a reduction of bandwidth, and therefore of thermal noise, at the expense of an increase in spectrum-truncation distortion. It is shown that the peak factor may be usefully reduced when the design carrier/noise ratio is high, but not when it is low, since such action raises the effective f.m. threshold.