1. Range-Ambiguous Clutter Suppression for Space-Based Early Warning Radar Using Vertical FDA and Horizontal EPC.
- Author
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Qiu, Zizhou, Liao, Zhipeng, Xu, Jingwei, and Duan, Keqing
- Abstract
The range-ambiguous clutter in space-based early warning radar is more severe compared with that in airborne radar due to the faster movement velocity. Meanwhile, the clutter angle-Doppler characteristics vary with range owing to Earth’s rotation. As a result, the mainbeam clutter returned from different ambiguous ranges occupies most of the Doppler spectrum, which leads to the degradation of the traditional space–time adaptive processing (STAP) performance in canceling clutter. Though frequency diverse array (FDA) based on multiple-input multiple-output (MIMO) can provide the ability to identify the range-ambiguous clutter, it cannot perform well for space-based early warning radar because of the finite available vertical elements. In this letter, a novel STAP method, which utilizes the element-pulse coding (EPC) and FDA technique to mitigate the range-ambiguous clutter, is proposed. First, EPC is used to prewhiten the most range-ambiguous clutter via coding and decoding in horizontal elements and coherent pulses. Then the interval in the vertical frequency of the residual range-ambiguous clutter is expanded by FDA, and thus the targets and clutter from the vertical mainlobe are easily extracted using a spatial filter with a few vertical elements. Finally, the extracted clutter can be effectively suppressed through the traditional STAP method. Simulation results are provided to demonstrate the performance of the proposed method. [ABSTRACT FROM AUTHOR] more...
- Published
- 2023
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