(AM) is the earliest form of radio transmission.
It applies a simple combination of a
carrier wave and a modulating wave (the
message). For example, a carrier wave
The signal that we wish to broadcast
The modulated signal is then
(FM) uses the modulating signal to vary
the frequency of the carrier signal.
FM signals are generally more robust
and are capable of carrying higher fidelity
1874-1937) was the first to
successfully transmit radio signals
across the Atlantic Ocean using
a telegraph, in 1901.