Detection and tracking of the trajectories of dynamic UAVs in restricted and cluttered environment

•A novel smoothing data association idea in the LM-IPDA algorithm.•The significant detection and tracking performance of UAV are analyzed by experiment.•Backward multi-tracks are used to estimate a forward track in past scan for smoothing.•False-track discrimination is obtained using smoothing target existence probability.•The algorithm reduces RMS errors, and tracks multi-vehicles in clutter efficiently.