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A Star Pattern Recognition Technique Based on the Binary Pattern Formed from the FFT Coefficients

A star sensor has become one of the most widely used attitude sensors for the satellite missions in the past decade. When no prior attitude information is available, it operates in a Lost-in-space (LIS) mode. The star pattern recognition technique forms the most crucial part of star sensor in the LIS mode. In this paper, we propose a novel star pattern recognition technique for an LIS mode star sensor. Firstly, a discrete sample signal is formed from the features extracted from the star image. Later, a 1D FFT is applied on the discrete sample signal. Finally, a binary pattern is formed from the relative magnitude of consecutive FFT coefficients for finding a match between the image and the database. Experiments are performed on simulated star images with missing and false stars. The proposed approach robustly maintains the identification accuracy to 97% on the swayed and biased simulated images.