Patent ID: 7262711
Filing Date: 2007-08-28
Classification: G07B

Abstract:
1. An external indicator for use in proximity to an on-board unit of an electronic toll collection system, the electronic toll collection system including a roadside unit for communicating with the on-board unit and conducting an electronic toll collection (ETC) transaction, the on-board unit including an on-board antenna and an on-board transceiver for sending and receiving RF transmissions and an on-board processor for controlling the on-board transceiver and conducting the ETC transaction with the roadside unit, the external indicator comprising: an RF antenna; an RF detector coupled to said RF antenna for demodulating an RF signal induced in said RF antenna by an RF transmission and for outputting a demodulated signal; a processor having an input for receiving said demodulated signal and an output for providing an indicator signal, the processor having a component for determining if said demodulated signal is indicative of an ETC transmission between said on-board unit and said roadside unit and, if so, generating said indicator signal, wherein said component is configured to determine that said demodulated signal is indicative of said ETC transmission by identifying that said demodulated signal comprises a transponder response signal from said on-board unit; and an indicator device coupled to the output of said processor, said indicator device producing a sensory event in response to said indicator signal.