Method of measuring vehicle speed and vehicle length based on rectangular single coil

The invention relates to an intelligent transportation system (ITS), and particularly relates to a method of measuring a vehicle speed and a vehicle length based on a rectangular single coil. The method comprises steps: time-frequency data of a standard vehicle passing through a rectangular coil at a certain speed is obtained; fitting processing is carried out to obtain a time-frequency curve; a slope of a certain section at the rising edge of the curve is taken, and the slope and the speed serve as a standard slope and a standard speed; when a to-be-measured vehicle passes through the rectangular coil at a certain speed, the time-frequency curve of the vehicle is obtained in the same method, and the curve is recorded to be a to-be-measured curve; a transformation factor is defined, and f-f transformation is carried out on the to-be-measured curve; a slope of the same section at the rising edge of the curve after transformation is taken, the standard slope and the standard speed serve as known parameters, the ratio of slopes is the same as the ratio of the speeds, the vehicle speed is obtained, and transportation information such as the vehicle length, the vehicle flow and a road occupancy rate can be further acquired.