A fast pulse phase estimation method for X-ray pulsar signals based on epoch folding  

作　　者：Xue Mengfan Li Xiaoping Sun Haifeng Fang Haiyan 

机构地区：[1]School of Aerospace Science and Technology,Xidian University

出　　处：《Chinese Journal of Aeronautics》2016年第3期746-753,共8页中国航空学报（英文版）

基　　金：supported by the National Natural Science Foundation of China(No.61301173)

摘　　要：X-ray pulsar-based navigation （XPNAV） is an attractive method for autonomous deep- space navigation in the future. The pulse phase estimation is a key task in XPNAV and its accuracy directly determines the navigation accuracy. State-of-the-art pulse phase estimation techniques either suffer from poor estimation accuracy, or involve tile maximization of generally non- convex object function, thus resulting in a large computational cost. In this paper, a fasl pulse phase estimation method based on epoch folding is presented. The statistical properties of the observed profle obtained through epoch folding are developed. Based on this, we recognize the joint prob- ability distribution of the observed profile as the likelihood function and utilize a fast Fourier transform-based procedure to estimate the pulse phase. Computational complexity of the proposed estimator is analyzed as well. Experimental results show that the proposed estimator significantly outperforms the currently used cross-correlation （CC） and nonlinear least squares （NLS） estima- tors, while significantly reduces the computational complexity compared with NLS and maxinmm likelihood （ML） estimators.X-ray pulsar-based navigation （XPNAV） is an attractive method for autonomous deep- space navigation in the future. The pulse phase estimation is a key task in XPNAV and its accuracy directly determines the navigation accuracy. State-of-the-art pulse phase estimation techniques either suffer from poor estimation accuracy, or involve tile maximization of generally non- convex object function, thus resulting in a large computational cost. In this paper, a fasl pulse phase estimation method based on epoch folding is presented. The statistical properties of the observed profle obtained through epoch folding are developed. Based on this, we recognize the joint prob- ability distribution of the observed profile as the likelihood function and utilize a fast Fourier transform-based procedure to estimate the pulse phase. Computational complexity of the proposed estimator is analyzed as well. Experimental results show that the proposed estimator significantly outperforms the currently used cross-correlation （CC） and nonlinear least squares （NLS） estima- tors, while significantly reduces the computational complexity compared with NLS and maxinmm likelihood （ML） estimators.

关 键 词：Epoch folding Maximum likelihoodPhase estimation X-ray pulsar X-ray pulsar-basednavigation （XPNAV） 

分 类 号：V448.2[航空宇航科学与技术—飞行器设计] P128.4[天文地球—天体测量]