High-performance subpixel edge location based on FPGA for horizon sensors

Abstract Horizon edge localization accuracy and speed are key factors in the performance of horizon sensors. This paper proposes a high-performance sub-pixel edge localization algorithm base on Field Programmable Gate Array (FPGA) for horizon sensors. The algorithm is carefully designed and simplified according to the computational capabilities and limitations of FPGAs. By making full use of the parallel computing capability of FPGA and carrying out multi-stage pipeline design, the algorithm can complete image acquisition, rough edge localization, sub-pixel edge localization, and projections from pixel points to unit vectors at the same time, which greatly reduces the delay caused by image processing. The experimental results show that FPGA-based image processing shows a significant superiority in terms of speed compared to traditional embedded processors.