Review on Space High Precision Time-Frequency Transfer Technology

Spatial high-precision time-frequency transfer technology will promote the application of high-precision time frequency reference. It is the core competence to establish a spatial time-frequency system. This paper describes the error of space high-precision time-frequency transfer and reviews the development of time-frequency transmission technology. The evolution of transmission carrier from microwave to laser, error processing from terminal direct measurement to system precision correction, transfer accuracy from ns level to ps level or even higher, application scenarios from single link building to constellation networking, from satellite- ground link, inter-satellite link to serving deep space are concerned, which will promote technological upgrading of ultra-high precise time-frequency transfer.