Vehicle mileage meter and a GPS position tracking system

A calibrated electronic taximeter system for a taxi, comprising:

• a GPS receiver/computer system having an input terminal for receiving input odometer pulses from a taxi odometer, said GPS receiver/computer system providing GPS information as output signals;
• wherein the GPS receiver/computer system provides continuously calibrated odometer output pulses as a function of the received GPS information, when the GPS information is available and wherein the GPS receiver/computer system includes a dead reckoning subsystem which provides location information to the GPS computer system during GPS receiver system service outages;
• a taximeter which receives calibrated odometer output pulses from the GPS receiver/computer system and which receives the GPS information, said taximeter computing and displaying a taxi fare from the calibrated odometer output pulses and from the GPS information provided by said GPS receiver/computer system;
• wherein the GPS receiver/computer system provides trip information, which trip information includes information selected from the group consisting of information about when and where a vehicle enters and leaves a predetermined zone, information establishing proof of a path followed by a taxi, information about operation within speed limits, and information verifying operation within a certain geographic area;
• and
• a data recorder which records the trip information.

A method of calibrating a mileage meter installed in a commercial vehicle, comprising the steps of:

• providing GPS position information and GPS time information as output signals from a GPS receiver/computer system;
• receiving input odometer pulses from an odometer;
• providing calibrated odometer output pulses as a function of the received GPS velocity information and GPS time information;
• computing mileage traveled in a mileage meter from the calibrated odometer output pulses provided by said GPS receiver/computer system;
• using a dead reckoning navigation system for providing location information to the GPS computer system during GPS receiver system service outages;
• providing trip information for the commercial vehicle;
• recording the trip information;
• and
• wherein the step of providing the trip information includes information selected from the group consisting of the step of providing information about proof of a path followed by the commercial vehicle, providing information about operation of the commercial vehicle within speed limits;
• and providing information about certification of operation within a certain geographic area.