Research on distributed multistatic sonar target tracking technique

Compared with monostatic sonar, multistatic sonar has a better tracking effect and a wider visible tracking range for underwater target tracking. The distributed fusion structure is widely used in multistatic sonar tracking systems because the cost is low, the calculation is simple and it is easy to achieve overall. In the distributed system, each sonar tracks the target and estimates the states independently. The tracking information is sent to the fusion center to complete the tasks of coordinate transformation, data calibration, track association and track fusion. In this paper, analysis and performance simulation of the theory in distributed multistatic sonar target track association and track fusion are given. The track processor is based on the PDAF and the Kalman filter. The track association uses two kinds of statistic association algorithm (sequential track method, and statistic double threshold association method). The track fusion is based on distributing the error covariance of the tracking system. In the track association phase, two association algorithms are discussed. One is a sequential track algorithm, which connects the history of the track with the present association state. The other is a statistic double threshold association algorithm. The first threshold of the sequential track algorithm is based on the theory of counter. The second threshold depends on the association quality and separation quality. The final determination of the statistic double threshold method on whether the tracks are from the same target and could be associated or not can be given after double threshold processing. The simulated performances of the algorithms are then discussed. In the track fusion phase, by distributing the error covariance of the system, the tracks which associated successfully are fused in the unified coordinate transformation to achieve better tracking accuracy, and the simulation analyses for bi-target algorithms in the multistatic system are given.