TaiJing-4(03) satellite is the world's first high resolution flat-panel Ku-band Synthetic Aperture Radar (SAR) commercial satellite, characterized by the high resolution, light weight design, low cost, multiple imaging modes and long-term operation. A series of key technologies and innovations are adopted, such as lightweight and high-resolution Ku-band SAR payload, on-board intelligent imaging processing, non-uniform pulse sparse reconstruction of high resolution and wide width SAR imaging technology, target detection and recognition capability improvement, high precision and high stability attitude measurement and control, 2D guidance composite control, and multi-target imaging efficiency improvement. It achieves high resolution, high image quality and high image acquisition efficiency. The Ku-band SAR satellite has stronger perception of target details, and has multiple workmodes such as spotlight, sliding spotlight, strip, scanning, wide-width scanning, and multi-target imaging, which significantly improves satellite observation performance, coverage capability and application efficiency. It has important applications in high-resolution observation, emergency disaster relief, marine environment monitoring, resource investigation, etc.