Abstract: A method of simultaneously estimating a movement and shape of a target vehicle using a preliminary distribution model of a tracklet may have high reliability in estimation performance even with a change in heading of the target vehicle while being implemented in real time by setting the preliminary distribution model defined by a small number of representative tracklet appearance points using a tracklet defined in an orthogonal coordinate system and a linear correspondence relationship between a preliminary distribution model of the tracklet and a central position of the target vehicle and performing many-to-one data association between tracklet outputs. The method of simultaneously estimating the movement and shape of the target vehicle using the preliminary distribution model of the tracklet is performed by a signal processing device configured to process signals emitted from a plurality of radars mounted at a host vehicle and reflected from the target vehicle.