Clutter suppression and target energy focussing for airborne rotating antenna radar using improved Space‐time adaptive processing

Abstract

Abstract Rotating antenna radar is widely used on the airborne platform to extend the range of the radar detection airspace. However, the echo signal received by an airborne rotating radar is spread in the Doppler domain due to the platform motion and the antenna rotation. In the process of a long‐time integration, the antenna rotation harms the signal‐to‐noise ratio and reduces the performance of target detection when using conventional processing methods. Although conventional space‐time adaptive processing (STAP) has been used successfully to suppress clutter on an airborne radar, it does not take into account the antenna rotation. It decreases the performance of clutter suppression on the airborne rotating antenna radar. The signal model of airborne rotating antenna radar is analysed and the STAP technique to the rotating antenna scenario is improved to effectively suppress clutter and focus on target energy. Firstly, the echo of the airborne rotating antenna radar is modelled. Secondly, the factors affecting the Doppler difference of the array elements are investigated. Thirdly, an improved STAP method is proposed. Finally, the effect of antenna rotation on clutter Doppler characteristics and the clutter suppression and target energy focussing on the effects of the improved STAP technique are investigated. Experimental results demonstrate the effectiveness of the proposed method.