Bernoulli track-before-detect smoothing for maritime radar

Detection and tracking of small targets in sea clutter using a high-resolution radar is a challenging problem as the sea surface constantly moves in a complex manner, with rough seas creating strong target-like returns. Recently, a Bernoulli track-before-detect (TBD) filter has been developed for an airborne scanning radar in the maritime domain. Its purpose is to detect and track short-exposure targets by using the radar in a fast scanning mode. The current paper investigates the potential improvement in detection and tracking performance of the Bernoulli TBD filter by incorporating a backward smoothing step. The developed algorithm, referred to as the Bernoulli TBD forward-backward smoother (FBS) for maritime radar, is making a delayed decision by taking into account multiple future scans of radar data. A numerical analysis of a joint detection and tracking error with a fixed-lag smoothing is presented, as a function of the number of delay lags, signal-to-interference ratio and the sea clutter spikiness.