A pair of radio frequency communication devices and a communication method
are provided according to the invention. A transmitter includes a data
source providing a data stream and a radio frequency modulation device.
The radio frequency modulation device communicates with the data source
and performs a modulation of a carrier wave according to the data stream
provided by the data source. The data stream controls one or more
modulation characteristics of the carrier wave. A corresponding receiver
includes a modulation key and a modulation detector. The modulation key
includes a plurality of modulation patterns. The modulation detector
receives a radio frequency communication signal and communicates with the
modulation key. The modulation detector maps portions of the received
communication signal to the modulation key in order to detect modulation
characteristics in the received communication signal and to generate a
data output.