In order to solve the problem that the number of primary transmitting coils is increased due to the layout structure of the segmented railways in the dynamic wireless power supply system, and the real-time switching control of the transmitting coils in each segmented railway is required, a dynamic RF position detection method is proposed in this paper. A high-performance 433MHz RF circuit was designed by using RF chips and a directional PCB on-board antenna was designed to improve the directivity of the position detection system. By adjusting the transmit power and receiving sensitivity of the module to control its communication distance and test its penetrability and anti-interference ability, and finally verifies that it has a good performance.