Vehicles Positioning in Tunnel: A Real-Time Localization System Using DL-TDOA Technology

Due to the dim light in the tunnel and the characteristics of natural electromagnetic shielding, drivers are prone to accidents in the tunnel and are unable to inform the navigation system in time. Therefore, it is still a bottleneck in the field of intelligent transportation how to obtain real-time vehicle position information and vehicle state information when the vehicle is running at high speeds in the tunnel. In this paper, a new technology is proposed to achieve accurate real-time positioning in the tunnel scene by combining the downlink time difference of arrival (DL-TDOA) with UWB technology. The DL-TDOA technology is based on Ultra Wide Band (UWB) data transmission technology, which can effectively reduce the interference of other electromagnetic waves and reduce the data transmission time. By calculating the transmission time of the wireless electromagnetic wave between the vehicle and the fixed base station, the technology can determine the real-time position of the vehicle and greatly reduce the time loss of data in transmission. DL-TDOA based on UWB technology has high precision, while DL-TDOA based on UWB technology has many advantages, such as high precision, strong anti-jamming ability, low power consumption and a high transmission rate which are suitable for accurate positioning and navigation in tunnel scenarios. In the final tunnel experiment, several tests were carried out at speeds of 30km/h, 60km/h and 80km/h respectively. By comparing the coordinate position after the conversion with the satellite coordinate, the real-time kinematics (RTK), it was concluded that the position error of vehicles in the tunnel is less than 1m, and the real-time positioning of vehicles in the tunnel is realized.