I need to transmit small bursts of repetetive digital data via RF (or
otherwise wireless)  in an automotive type environment and receive same via
a separate receiver approximately 6 feet away.  The method must be very
reliable and made so as not to cause or receive interference from sources
external  to the circuit.
Can anybody provide some feedback as  to how one might (as simply as
possible) design such a connection?
Any and all help is greatly appreciated.

Bill Kichman
Cornwall, PA USA