Abstract: An electronic toll collection (ETC) system comprises an on-vehicle unit mounted on a vehicle and a stationary-station communication system. This communication system operates to perform communication for accounting processing toward the on-vehicle unit mounted on the vehicle that passes a predetermined communication area. The stationary-station communication system comprises a controller and an antenna unit. The controller includes a protocol controller configured to produce a protocol selection signal and a communication controller configured to control the communication based on the produced communication protocol selection signal. The antenna unit includes a modem unit configured to selectively have a plurality of types of modulation/demodulation techniques corresponding to a plurality of types of protocols for the communication and control means configured to selectively allow the modem unit to be switched into a particular modulation/demodulation technique specified by the protocol selection signal.

Abstract: In an ETC on-vehicle device (1), notification of toll amount information is given with a sound production pattern of a buzzer (17). The toll information resulting from toll collection being conducted with a road antenna is converted to a sound production pattern by a CPU (11). For example, if the toll is 12,300 yen, the buzzer (17) sounds once with a long sound, twice with a middle sound, and three times with a short sound.

Abstract: In an ETC on-vehicle device (1), notification of toll amount information is given with a sound production pattern of a buzzer (17). The toll information resulting from toll collection being conducted with a road antenna is converted to a sound production pattern by a CPU (11). For example, if the toll is 12,300 yen, the buzzer (17) sounds once with a long sound, twice with a middle sound, and three times with a short sound.

Abstract: An electronic toll collection (ETC) system comprises an on-vehicle unit mounted on a vehicle and a stationary-station communication system. This communication system operates to perform communication for accounting processing toward the on-vehicle unit mounted on the vehicle that passes a predetermined communication area. The stationary-station communication system comprises a controller and an antenna unit. The controller includes a protocol controller configured to produce a protocol selection signal and a communication controller configured to control the communication based on the produced communication protocol selection signal. The antenna unit includes a modem unit configured to selectively have a plurality of types of modulation/demodulation techniques corresponding to a plurality of types of protocols for the communication and control means configured to selectively allow the modem unit to be switched into a particular modulation/demodulation technique specified by the protocol selection signal.

Abstract: A communication system between a host station and a plurality of substations eliminates the possibility of a connection failure between the host and a given substation by attempting to establish a communication session a finite number of times. The host station transmits and receives data to and from the substations and processes the data. Every time one of the substations receives a pilot command from the host station, it selects a time slot provided in the host station's operation schedule based on digit information of the substation's unique ID code and transmits a response signal in that time slot to the host. If the response conflicts with another substation's response, information based on a different digit in the ID code is selected. Because the ID code is unique to the substation, a communication session will eventually be established, and the probability of a conflict with a response from another substation is reduced to zero by re-transmission by transmitting the request a finite number of times.