fm modulation


Joined Jan 18, 2005
By FM signals I assume you mean the 88 to 108-MHz VHF broadcast band. These frequencies rely primarily on sky wave propagation rather than ground wave propagation. Sky wave propagation being a function of antenna height. For a given transmitter antenna height, the higher the receiver antenna the better the reception. Although VHF is not quite "line of sight" this priciple is used to calculate reception/communication distances. Rough terrain and buildings can adversely affect the reception path as well.

Take a look at the spreadsheet attachment.