Abstract: An RF based communication system includes a transmitter for transmitting a signal. The transmitter is powered by an external power source and has a transmitter counter for generating a count. The count is linearly incremented over time. The transmitted signal includes the count at the time that the signal is transmitted. A receiver is communicatively coupled to the transmitter for receiving the signal transmitted by the transmitter. The receiver has a receiver counter, the receiver counter being asynchronous with respect to the transmitter counter.