第三代卫星导航定位系统星载原子钟的新发展  

The new Creations and Developments of on-board Atomic Clocks for the 3rd Generation of GNSS

作　　者：翟造成[1] 杨佩红[1] 

机构地区：[1]中国科学院上海天文台,上海200030

出　　处：《天文学进展》2008年第4期301-310,共10页Progress In Astronomy

摘　　要：传统铷原子钟和铯原子钟已在卫星导航定位系统中作为星载原子钟获得重要应用.卫星导航定位系统的更新和新发展要求更高精度更小型的新型星载原子钟.该文介绍采用新物理原理和先进技术在下一代卫星导航定位系统有应用前景的新原子钟的产生和发展以及它们目前的进展.In satellite navigation and positioning system, the high performance atomic clocks take an important place. In particular the on-board clocks which are key component to reach the positioning performance. Since its creation, the GPS system has already used two different tech- nologies, Rb clocks and Cs clocks. Concerning the Galileo system, two technologies are specified for the first generation of satellite. The first one is also a Rb clock while the second is a passive H maser, which has not been spatialized before. These two kinds of clocks （ Rb and Cs ） are based on the same concept of atomic vapor cell, which is particularly sensitive to the environment, limiting mid and long term stability performances. In the case of the Cs clock, the principle is different, the atoms used in an atomic beam. This characteristics allows to reduce the effects of the environment and to reach better mid and long term stability performances. However, the Cs clocks on-board GPS satellite are based on the magnetic state selection technology, the frequency stability required for space clocks of the 3rd generation of GNSS, including Galileo, can＇t be reached with the magnetic state selection technology. In the case of the Rb clocks, state selection uses spectrum lamp pumping with low pmnping efficiency, creating big optical shift, limiting stability performances so that is also difficult to satisfy the frequency stability required for future advanced satellite navigation system. The solution proposed for the next on-board clocks is the laser approach with following advanced technologies to overcome the disadvantages mentioned above in the traditional Cs and Rb clocks ： （1） the laser optical pumping technology for state selection allows to use much more atoms and to increase pumping efficiency, improving the signal to noise ratio of the atomic resonator and consequently the frequency stability of the clocks; （2） the laser cooling and trapping technologies allow to low down the velocity and temperature of the atoms,

关 键 词：新型星载原子钟 卫星导航定位系统 研制进展 

分 类 号：P111.44[天文地球—天文学]