详细介绍了一种星敏感器像素频率误差补偿方法并结合实际实验数据对其补偿效果进行验证。首先依据阈值分割的星点提取算法, 分析了像素频率误差产生的几个主要原因。然后改进原有的星点质心定位点扩散函数, 提出了一种基于亚像元坐标的像素频率误差补偿方法。最后通过星敏感器微步距实验, 与正弦曲线法比较。实验结果表明: 在视场中心区域, 使用该方法对采样点补偿后像素频率误差减少了65.2%, 优于正弦曲线法的52.7%; 使用视场中心的误差补偿公式对视场边缘的采样点补偿, 像素频率误差减少58.7%, 优于正弦曲线法的41.9%。由实验结果可得: 较之于正弦曲线法, 该误差修正方法不仅具有更好的误差补偿效果, 而且在视场范围内具有较强的通用性。

A pixel frequency error compensation method of star sensor was introduced in detail, and the compensation effect was verified by the experimental data. At first, based on threshold segmentation algorithm for star extraction, the main reasons of pixel frequency error were analyzed. Then, the original point spread function of centroid location was improved and a pixel frequency error compensation method based on sub-pixel coordinates was proposed. Last, through the micro-pace experiment of star sensor, it was compared with sine curve method. Experimental results show that: in the center of the field of view, the pixel frequency error of the sampling point is reduced by 65.2% using this method, which is better than 52.7% of the sine curve method; using the error compensation formula of the field of view to compensate for the sampling point of the field of view, the pixel frequency error is reduced by 58.7%, which is better than 41.9% of the sine curve method. By the experimental results, compared with sine curve, this error correction method not only has better error compensation effect, but also has strong versatility within the field of view.