利用射电暴发信号测量系统间时延的研究

Research on measuring time delay between systems using radio burst signals

利用中国科学院国家授时中心昊平站的射电望远镜,开展基于PSR J0534+2200发射的巨脉冲信号测量两个观测系统之间时间延迟的研究。两个时间频率参考信号不同的观测系统同时对射电望远镜接收到的PSRJ0534+2200脉冲星信号进行独立观测,一共观测4次,共观测4.5h。经测量,PSR J0534+2200发射的同一巨脉冲信号在两个系统中到达时间不同,巨脉冲到达时间之差即为两个系统之间的时间延迟。采用三次样条内插法和高斯拟合法对巨脉冲的轮廓拟合,将拟合轮廓的峰值相位作为巨脉冲的到达时间。通过对测量系统时延的误差统计,结果表明:利用原始轮廓的峰值相位测量系统误差均方根小于57µs,三次样条内插法测得均方根误差小于13µs,高斯拟合法测得均方根误差小于7µs。相较于利用原始轮廓的峰值相位测量系统误差,采用三次样条内插法以及高斯拟合法对于系统延迟的精度分别提升了3.9倍和8.6倍,为利用射电暴发信号进行高精度的时间同步打下基础。

Using the radio telescope at Haoping Station of the National Time Service Center of the Chinese Academy of Sciences,the study on measuring the time delay between two observation systems using the giant pulses from PSR J0534+2200 is carried out.PSR J0534+2200 was observed for four times with two observation systems with different time and frequency reference signals simultaneously and independently.The total observing time is 4.5 hours.The arrival time of the same giant pulse signal transmitted by PSR J0534+2200 is different in the two systems.The difference in the arrival time of the giant pulse is considered to be the time delay between the two systems.The cubic spline interpolation method and Gaussian fitting method are used to fit the profile of the giant pulse,and the peak phase of the fitted profile is taken as the arrival time of the giant pulse.The analysis of the error of the measuring system time delay shows that the root mean square error of the measuring system using the peak phase of the original profile,cubic spline interpolation,and the Gaussian fitting are less than 57µs,less than 13µs,and less than 7µs,respectively.Compared to the method using the peak phase of the original profile to measure the system error,the accuracy of the system delay using the cubic spline interpolation method and Gaussian fitting method has been improved by 3.9 and 8.6 times,respectively,laying the foundation for high-precision time synchronization using radio burst signals.