Abstract: A vehicle monitoring system is described having an arrangement installed within a vehicle, wherein the system includes an external data terminal for communicating information to a remotely located base station. The arrangement includes a plurality of communication modules, each being capable of communicating messages associated with performance of the vehicle; a data bus member for electrically intercoupling the plurality of communication modules and for receiving the communicated messages therefrom; a driver interface module for transmitting messages to and for receiving messages from a vehicle operator; and a recorder coupled to the data bus member for recording information associated with performance of the vehicle which has been transmitted over the data bus member by the plurality of communication modules, coupled to the driver interface module via a second data bus member for transferring messages therebetween.

Abstract: In a communication system having a communication channel for transmitting data between a base station and a plurality of mobile radio units, wherein each radio unit has a unique identification (ID) code and wherein transmissions from each radio unit to the base station include the unit's ID code, a method is described for identifying which units are within RF communication proximity of the base station. The method includes: transmitting a range message, including a low ID code parameter and a high ID code parameter, from the base station over the channel to elicit a response from at least one of the mobile radio units having an ID code between the low and high parameters; determining whether radio units transmitted a message in response to the range message; and storing, responsive to transmission by the units, in an ID list a signal representative of the respective ID code assigned to such transmitting units.