1. Introduction
Due to vastness of global ocean, the maritime surveillance is of great significance in sea rescue, sea environmental protection, and sea resource management [1]. However, the radar will be interfered by strong sea clutter when implementing the sea surface target detection tasks. Because of the wind field and ocean current, the sea surface is in constant complex motion, and the complex random internal motion makes the sea clutter exhibit completely different temporal and spatial characteristics compared with those of land clutter. These properties are embodied in the clutter amplitude statistical distribution, space-time decorrelation characteristics, space-time power spectrum, etc. [2]. Due to the time-varying and space-varying properties, the sea clutter suppression and marine moving target detection become difficult, especially in a high-state sea scene.