Method and field experiment of target tracking via multi‐static Doppler shifts in high‐frequency passive radar

The passive radar (PR) systems working in the high‐frequency (HF) band take advantage of numerous high‐power stations and long wavelength, which are useful for anti‐stealth, while suffering from the bad range resolutions compared with systems working in other bands. In this study, the method and field experiment of tracking a close‐in moving target via only Doppler‐shift data provided by an HF PR are described. The non‐cooperative illuminators are far away from surveillance area, the direct wave and illumination wave reach the receiver and target, respectively, via reflection from the ionosphere, while the echo scattered from the target propagates directly to the receiver by line of sight. The Doppler measurement model in this particular multi‐static scenario is proposed and the Gaussian mixture Bernoulli filter is introduced to process the Doppler data to estimate the target position and velocity. The experiment of tracking a close‐in civilian aeroplane was carried out using an experimental PR system. The estimated target positions and velocities are provided and compared with the true values derived from the automatic dependent surveillance‐broadcast data. The initial result indicates the feasibility of this method used in a practical PR system for moving target tracking.