为了满足偏振光导航中对天空特征点位置信息的需求, 提出一种基于Rayleigh大气偏振模式的太阳和太阳子午线空间位置的计算方法.首先分别利用瑞利单次散射理论和偏振分析仪重建了理论和实测大气偏振模式, 再根据大气偏振分布模式的特点, 对所采集的偏振度数据和E-矢量数据进行聚类分析, 利用偏振度数据确定太阳位置, E-矢量数据确定太阳子午线位置, 将求取太阳和太阳子午线空间位置的问题转化为确定相应类中心的问题.最后对所提方法分别就大气偏振的理论模式和实测模式进行实验分析, 与最小二乘法利用偏振数据反推太阳位置法相比, 该方法有效地利用了偏振模式整体分布的稳定性特点, 可以通过采集大范围偏振信息获取较准确的空间显著特征点位置, 得到较好的实测数据处理结果.

An approach to the location of the sun and meridian by means of the Rayleigh skylight polarization pattern was introduced, given that the polarized-light-aided navigation relys heavily on the position of some astronomical markers. Combining with the theoretical analysis based on the single Rayleigh scattering theory, the skylight polarization pattern was practically detected the using the polarization analyzer. Then, with respect to the distribution stability of the polarization pattern, the information collected was clustered to locate the position of the sun with the polarization degree data, and that of the solar meridian with the E-vector data respectively. In this way, the location problem was changed to figure out the clustering center. Finally, the approach was tested through experiments on the theoretical and practical detected polarization pattern. Compared with the way of obtaining the solar location by the least square method, this approach can effectively take use of the stable distribution of the polarization pattern, locate the accurate position of astronomical marker based on the polarization information detected on a large scale, and skillfully process the captured data.