一种求解X射线脉冲星导航周期模糊数的新方法  

A New Method for Resolving Integer Pulse Cycle Ambiguities in X-ray Pulsar-based Navigation

作　　者：郭星灿[1] 杨博[1] 

机构地区：[1]北京航空航天大学宇航学院,北京100191

出　　处：《航天控制》2009年第4期14-18,共5页Aerospace Control

摘　　要：因为X射线敏感器不能分辨具体的脉冲,X射线脉冲星导航方法存在整脉冲周期模糊数问题。现有求解周期模糊数的方法过程复杂,计算量大。本文在飞行器估计位置十分精确的假设下,提出了无周期模糊数的X射线脉冲星迭代滤波导航方法。UKF滤波器基于轨道动力学给出探测器的估计位置,以脉冲到达标称位置和估计位置的时间差作为反馈,进行迭代滤波,最终得到探测器的真实位置和速度估计。仿真表明,该方法能在火星探测器的日心转移轨道上实现高精度的导航,其精度可达到位置误差5km和速度误差0.5m/s。The X-ray pulsar-based navigation method has a problem of the integer pulse cycle ambiguity because the X-ray detector can not identify specific pulses. Existing approaches to resolve the ambiguity are computationally intensive and may require large processing time. Assuming that the estimated position is very accurate, this paper proposes a recursive X-ray pulsar-based navigation method without any ambiguity. The paper provided a description of blending the vehicle dynamics with the pulse time-of-arrival differences at nominal and estimated spacecraft locations within an unscented Kalman filter （UKF）for recursive determina- tion of Mars probe position and velocity. The simulation illustrates that this scheme has excellent perform- ance on the heliocentric transfer orbit, with perfect accuracies of position and velocity on the order of 5km and 0. 5m/s respectively.

关 键 词：X射线脉冲星 整脉冲周期模糊数 UKF 火星探测 

分 类 号：P128.4[天文地球—天体测量] P145.6[天文地球—天文学]