【摘要】 从1973年起国际权度局(BIPM)一直采用ALGOS算法计算自由原子时EAL。为了适应原子钟和比对链路性能的提升,BIPM时间部对EAL的计算方法做了多次修改,其中针对算法中的加权方法改进的次数最多,最近一次BIPM对EAL算法的修改是2014年,旨在降低铯钟在EAL计算中过高的权重,从而平衡氢、铯两类原子钟在EAL计算时的贡献。通过分析2014版新算法启用前后EAL计算中原子钟的权重分布情况,发现该算法中氢钟对EAL的贡献明显提高,但存在以下不足之处:一是在算法修改之后的所有时间段内,氢钟权重出现持续增加趋势;二是落在不同权值区间内钟数量、钟类型的分布状况不合理。针对这些不足,综合2001版和2014版EAL算法中原子钟的权重分布状况,对经典加权算法中权重的确定原则提出建议。更多还原

【Abstract】 BIPM has been using ALGOS algorithm to calculate the free atomic time(EAL)since 1973.In order to adapt to the improvement of performance for atomic clocks and comparison links,the BIPM time department has made many modifications to the calculation method of EAL,in which the weighting method is improved most frequently.The latest modification for the EAL algorithm was made by BIPM in 2014,aimed at reducing the weights of the cesium clocks in the EAL calculation,so as to balance the contributions of the hydrogen masers and cesium clocks in the calculation of EAL.By analyzing the weight distributions of atomic clocks based on before and after the 2014 version algorithm,we found that the contribution of hydrogen masers to EAL is significantly improved in the new algorithm.However,there are some deficiencies:weights of the hydrogen masers appear increasing trend since the new algorithm was applied;the number of clocks and the distribution of clock types are unreasonable in different weighting intervals.The determination principles of weight in the classical weighted algorithm is proposed through incorporating the weights distribution of atomic clocks in the 2001 and 2014 versions EAL algorithms.更多还原