基于S变换的脉冲星辐射脉冲信号检测  

Pulsar signal detection based on S-transform

作　　者：王璐[1] 许录平[1] 张华[1] 罗楠[1] 

机构地区：[1]西安电子科技大学电子工程学院,西安710071

出　　处：《物理学报》2013年第13期596-605,共10页Acta Physica Sinica

基　　金：国家自然科学基金(批准号:61172138);中国科学院精密导航定位与定时技术重点实验室开放基金(准批号:2012PNTT02)资助的课题~~

摘　　要：为了提高脉冲星辐射脉冲信号的检测速度和在低信噪比下的检测效果,提出了一种基于S变换的脉冲星辐射脉冲信号检测算法.文中证明了高斯白噪声S变换域功率谱服从自由度为2的卡方分布,基于此对累积信号S变换域功率谱进行阈值处理,累加阈值处理后的时频功率谱作为统计量进行检测.此外阈值处理后的功率谱也可用来测量脉冲星信号的时间延迟.仿真实验验证了本文算法的有效性,其检测性能优于同类的基于高斯分布模型的检测算法,同时还可以在一定精度下给出脉冲星信号的时间延迟值.In order to increase the detection speed and to improve the detection rate in low signal-to-noise ratio, a novel detection algorithm for pulsar integrated pulse profile is proposed based on S-transform. We prove that the local S-transform spectrum of Gaussian white noise follows chi-square distribution with two degrees of freedom in this paper, and based on this, threshold processing is operated on the S-transform power spectra of cumulative signal; then, the total energy of the time-frequency power spectral after threshold processing is accumulated to construct the detecting statistics to obtain the statistic decision. Moreover, the time-frequency power spectra after threshold processing can also be used to measure the time delay of pulsar signal. The simulation result verifies the effectiveness of the proposed method which is superior to a similar method based on the Gaussian distribution; in addition, it can give the time delay with a certain accuracy.

关 键 词：脉冲星 卡方分布 S变换域检测 时延测量 

分 类 号：P145.6[天文地球—天体物理]