一、绪言国际上都采用原子频率标准作为物理的时间尺度或频率的单位,为与历书时系(ET)相一致,暂定銫原子 F=4,mf=0和F=3,mf=0之间的跃迁频率为9192631770赫(原子时系 AT)。因此,自然要借助于原子频率标准用标准电波发送频率和时间信号,而这样做后,标准电波表示的时间信号和世界时,即自转时 I. INTRODUCTION Internationally, atomic frequency standards are used as units of physical time scales or frequencies in accordance with the almanac (ET), tentative Cesium atoms F = 4, mf = 0 and F = 3, mf = 0 The transition frequency between 9192631770 hertz (atomic time system AT). Therefore, it is natural to use the standard radio frequency atomic frequency standard to send the frequency and time signals, and in doing so, the standard radio time signal and world time, that is, when the rotation