一种基于泊松分布的提高X射线脉冲星脉冲轮廓信噪比的方法  

A method for improving the SNR of X-ray pulsar pulse profile based on Poisson distribution

作　　者：胡慧君[1,2] 赵宝升[1] 盛立志[1,2] 鄢秋荣[1,2] 杨颢[1,2] 陈宝梅[1,2] 

机构地区：[1]中国科学院西安光学精密机械研究所瞬态光学与光子技术国家重点实验室,西安710119 [2]中国科学院研究生院,北京100039

出　　处：《中国科学：物理学、力学、天文学》2011年第8期1015-1020,共6页Scientia Sinica Physica,Mechanica & Astronomica

摘　　要：论述了X射线脉冲星辐射模型和脉冲轮廓构造算法,提出了以Kullback-leibler距离函数作为评价标准,提高具有泊松分布规律的X射线脉冲星脉冲轮廓信噪比的平滑算法,推导了平滑参数和平滑累积脉冲轮廓的计算公式.搭建了X射线脉冲星导航地面模拟系统,实现了对模拟X射线脉冲星单光子到达时间的记录及X射线脉冲星脉冲轮廓的构造,得到了X射线脉冲到达时间TOA.在X射线脉冲星导航地面模拟系统上,对平滑算法进行了验证,结果表明该算法对于提高累积脉冲轮廓的信噪比效果显著,信噪比提高大于10dB.The radiation model of pulsar and the construction of pulsar integrated pulse profile are discussed,and a smoothing algorithm for improving the SNR of pulsar integrated pulse profile which obeys Poisson distribution is proposed based on Kullback-leibler distance function.The formula for calculating smoothing parameter and smoothing integrated pulse profile are deduced.A simulation experiment system for X-ray pulsar based navigation is setup in order to study the key technologies of X-ray pulsar navigation.The time of arrival of individual X-ray photon from the simulation X-ray pulsar source is recorded,the integrated pulse profile is constructed and the time of arrival of pulse is calculated in the simulation system.The smoothing algorithm is verified in the simulation system,and the results show that SNR can be improved by 10 dB.

关 键 词：X射线脉冲星导航 脉冲轮廓 信噪比 泊松分布 

分 类 号：P145.6[天文地球—天体物理]