Abstract: To position the personnel in railway tunnels in real time and ensure safe construction, a railway tunnel personnel positioning technology based on millimeter wave radar is proposed. Considering the characteristics of railway tunnel construction environment, a frequencymodulated continuous wave radar is used. First, the distance, velocity, and angle of the target point are measured by analyzing the frequency, time delay, and phase of the radar reflection wave, and the clutter elimination and target detection algorithm are used to obtain the point cloud of the target. Then, a target tracking algorithm is used to cluster and track the point cloud, obtaining and displaying the position, velocity, and trajectory of the personnel, and issuing alarms in a timely manner for abnormal behaviors. Finally, a semiphysical simulation environment is constructed. Radar nodes are deployed inside the tunnel, and processing servers are deployed outside the tunnel to experimentally verify the proposed technical solution. The research results show that a single radar node can simultaneously track the position distribution and posture information of at least six targets. The technical solution can meet the requirements of realtime and precise positioning of personnel in railway tunnels.

Key words: railway tunnel, personnel positioning, millimeter wave radar, frequency modulated continuous wave