【摘要】 利用综合脉冲星时（PT）具有较好长期频率稳定度的优点，将原子时驾驭到综合脉冲星时，可以改进其长期频率稳定度水平。文章描述了综合脉冲星时驾驭原子时的卡尔曼滤波方法。以美国海军天文台地方原子时TA(USNO)为例，采用卡尔曼滤波方法将地方原子时驾驭到国际原子时TAI，进而利用综合脉冲星时PT数据将其再驾驭到综合脉冲星时系统，最后得到经过2次频率驾驭后的PT-TA(USNO)钟差序列。考虑到综合脉冲星时PT包含有较大白频噪声，利用滤除其高频噪声后的PT驾驭原子时，能够获得更佳频率驾驭效果，驾驭后的钟差序列长期频率稳定度有明显提高。采用同样算法，将美国国家标准和技术研究院地方原子时TA(NIST)驾驭到TAI，再驾驭到PT，也得到相似结果。更多还原

【Abstract】 Ensemble pulsar time-scale(PT) derived from long term timing observations by pulsar timing array showed better long term frequency stability. Long term frequency stability of a steered atomic time-scale by ensemble pulsar time-scale can be improved. Kalman filtering method for steering an atomic time-scale using ensemble pulsar time-scale is described. As an example, the local atomic time-scale TA(USNO) kept by the Naval Astronomical Observatory is steered to the International Atomic Time-scale(TAI) and then further to an established ensemble pulsar time-scale by Kalman filtration. Because the ensemble pulsar time-scale contains larger white noise, a smoothed ensemble pulsar time-scale is derived. TA(USNO) is steered to TAI and then further to the smoothed ensemble pulsar time-scale PT. Fractional frequency stability analysis showed that the long term frequency stability for TA(USNO) steered to the smoothed PT is much improved than both the original TAI-TA(USNO) and steered TAI-TA(USNO). Using TA(NIST) kept by the National Institute of Standards and Technology as another example for steering atomic time to ensemble pulsar time-scale, the similar result is obtained.更多还原