一种高精度的X射线脉冲星导航TOA估计方法

摘要

针对 X 射线脉冲星导航（XPNAV）系统的基本观测量———脉冲到达时间（TOA）的估计问题，提出一种高精度的 TOA 估计方法。该方法基于特征子空间分解类算法的高精度的参数估计特性，首先通过细致分析标准轮廓与折叠轮廓之间的互相关结果，构造新的观测方程；然后对该方程进行特征值分解得到两个相互正交的特征矢量；最后利用两个特征矢量之间的正交性完成 TOA 估计。数值仿真结果有效校验了算法的性能。%For the problem of pulse time-of-arrival (TOA)estimation of X-ray pulsar-based navigation (XPNAV) system,a high-precision TOA estimation method is proposed.The method is expected to have a higher performance in precision,which is the characteristic of the eigen-decomposition algorithms.A new measurement equation is built based on the cross correlation function between the folded pulse profile and the standard pulse profile.The measurement equation is eigen-decomposed to generate a couple of orthogonal eigenvectors.The TOA is then estimated via the orthogonality of the eigenvectors.Numerical simulation is done and the results testify the precision performance of the newly proposed method.