Over-The-Horizon Radar Target Tracking Based on Spatial Correlation Ionosphere Model

Skywave Over-The-Horizon Radar (OTHR) relies on the earth's ionosphere which reflects its electromagnetic waves to achieve long range early warning of a variety of high-value targets. The model of ionosphere is the key factor for OTHR target tracking. Considering the spatial correlation of the Virtual Ionospheric Height (VIH) in different geographic locations, a new VIII model, represented by a Gaussian Markov Random Field (GMRF) and a new multipath target tracking method are proposed. Based on Bayesian estimation, the new method estimates jointly target state and VIHs under multipath and clutter environment. Given the limited measurements of the ionospheric subregions, the VIHs of the unmeasured subregions are inferred based on the GMRF model, thereby the precision of VIHs and the accuracy of the target tracking are improved. Numerical simulation shows that the accuracy of OTHR target tracking is improved.