Obu positioning, subdividing and calculating method and system

An OBU positioning, subdividing and calculating method and system. In a global positioning system-based city congestion charging system, an existing method and equipment can cause an error of omission in collecting fees when a vehicle passes through a preset charging point because positioning information is not output in time in the scenario where the speed of the vehicle is excessively fast. The method/system comprises: (1) receiving first positioning information output by a GNSS positioning and calculating module (104) at each integral second moment; (2) receiving sensor data cached in an accelerometer (102) and a gyroscope (101)at every fixed time interval; (3) calculating, according to the received first positioning information and the sensor data cached in the accelerometer (102) and the gyroscope (101), information about a relative position of the vehicle; (4) correcting and obtaining, according to the first positioning information and the information about the relative position, second positioning information; and (5) outputting absolute positioning information about the vehicle. The problem that positioning information is not output in time is solved, and omission in collecting fees when a vehicle passes through a preset charging point is prevented from happening.