基于双谱的脉冲星累积脉冲轮廓时间延迟测量

Time offset measurement algorithm based on bispectrum for pulsar integrated pulse profiles

为提高脉冲星辐射脉冲到达时间的测量精度,提出了基于双谱的脉冲星累积脉冲轮廓时间延迟测量算法.理论上,双谱可以完全抑制加性高斯白噪声.通过进行自双谱与互双谱的比对及求解极值点,推导出时间延迟测量公式.实验结果表明,基于双谱的时间延迟测量算法可以有效抑制高斯白噪声,当累积脉冲轮廓观测值存在噪声项时,基于双谱的累积脉冲轮廓时间延迟测量精度优于泰勒提出的功率谱算法.

In order to improve time offset measurement precision of pulsar integrated pulse profile and enhance the capability of noise suppression, a time offset measurement algorithm based on bispectrum for pulsar integrated pulse profile was proposed. Theoretically, bispectrum can completely suppress the additive Gaussian white noise, and the time offset in the third-order cumulants will result in phase rotation in the bispectrum. Time offset measurement algorithm based on bispectrum can be deduced by contrasting self-bispectrum and cross-bispectrum and solving the extremum formula. The results of experiments show that time offset measurement algorithm based on bispectrum can suppress the additive Gaussian white noise, and its precision is higher than that based on power spectrum proposed by Taylor.