--- In digitalradio@yahoogroups.com, "expeditionradio" <expeditionra...@...> wrote: > > Hi Andy, > > There is no simple universal relationship between > the "shift" and the transmitted "signal bandwidth",
However, for the particular case of binary FSK where the shift is wide compared to the bit rate, you get a reasonable approximation by treating the signal as a pair of carriers being switched on and off alternately. For each carrier you get pairs of sidebands. For the worst case of a square wave digital signal you'll get sidebands at the dot-cycle frequency and odd multiples thereof. So, depending on signal shaping, the signal at 850 Hz shift will have a bandwidth extending over about 950 Hz with a big hole in the middle.
