A remote transmitter system for vehicle applications includes a remote
transmitter for carrying by a user and a receiver for mounting on a
vehicle and receiving an amplitude modulated signal. The transmitter is
operative to transmit the amplitude modulated signal at a plurality of
different carrier frequencies. The receiver is programmed to select the
carrier frequency for reception by detecting noise due to unwanted
frequency modulated signals based on a received signal strength
indicator, and detecting noise due to unwanted amplitude modulated
signals based on a data decoder. The receiver changes the selected
carrier frequency when either noise becomes excessive.