基于时空混沌的海杂波背景下小目标检测

Detection of small targets within sea clutter using spatiotemporal chaos

近年来基于混沌理论对海杂波在时域内建模是比较好的工具,然而考虑到海面的电磁波散射是一个时空现象,提出将海杂波建模由原来的时域拓展到时空域建模,采用径向基耦合映像格子算法来重构海杂波的时空混沌动态特性,进而对嵌入在海杂波的小目标进行检测。通过对带有小目标的海杂波实测数据进行处理,能够较准确地检测出小目标的位置,验证了算法的可行性。此外,通过对实测海杂波数据处理,发现距离门含有小目标的海杂波回波幅值小于其他距离门不含有小目标的海杂波回波幅值,验证了海杂波与小目标的回波动态特性的不同。

In recent years, chaos is a powerful tool for modeling the sea clutter in time-domain. However, electromagnetic wave scattering from sea surface is indeed a spatiotemporal phenomenon, so the sea clutter modeling should be extended from time-domain to spatiotemporal domain. In this paper, the radial basis function coupled map lattices （RBF-CML） is presented to reconstruct the spatiotemporal chaotic dynamic characteristic of the sea clutter; then the small target within the sea clutter can be detected. This algorithm is validated by the real-life radar data that contains a small target, the position of the small target can be detected accurately, so the RBF-CML for small target detection is feasible. Besides, during processing the sea clutter data, we find that the amplitude of range bin hosting a target is lower than the other range bins that contain only sea clutter; this verifies the different baekscatter dynamic characteristics between sea clutter and small targets.