Wide-FOV and high-accuracy compound-eye-inspired sun sensor with orthogonal codes

Sun sensors play an important role in spacecraft pointing confirmation and solar tracking of photovoltaic systems. The existing single-aperture sun sensors face the contradiction that a wide field of view (FOV) and high angular measurement resolution cannot be achieved simultaneously. The multi-camera spliced sun sensors have the disadvantages of complex structure, large volume, and high power consumption. Inspired by the compound eyes of insects, a small-volume multi-aperture sun sensor has been developed. Based on the principles of detector multiplexing and orthogonal coding modulation, it projects the modulated solar images from different sky regions onto the same detector. By collecting the coded information, it can identify the sub-FOVs and achieve a wide FOV of 120°. The random errors are reduced by averaging the measurement results of multiple sub-eyes, and the high-accuracy solar direction vector is calculated with a resolution of 0.0001° and an accuracy of 0.0038° (1σ).