Multipath-Aware Detection and Tracking in Skywave Over-the-Horizon Radar

Skywave over-the-horizon radar is a sensing modality that exploits signal reflection from the ionosphere in the high-frequency band (3-30 MHz) to detect and track surface or airborne targets at ranges that are an order of magnitude greater than line-of-sight radar systems. Due to the stratified nature of the ionosphere, multiple propagation paths can be supported and a single target can appear as a family of returns. The conventional approach is to treat these multipath returns as independent targets and then employ downstream track fusion to associate and register the tracks from a common target. This paper presents an alternative "multipath-aware" approach that uses measurement fusion to combine multipath detections from a single target prior to tracking. The alternative method is illustrated on simulated data and compared with independently tracking each path.