Journal of Systems Engineering and Electronics ›› 2021, Vol. 32 ›› Issue (3): 596-606.doi: 10.23919/JSEE.2021.000051

• SYSTEMS ENGINEERING • Previous Articles     Next Articles

Integrated method for measuring distance and time difference between small satellites

Yaowei ZHU1(), Zhaobin XU1,*(), Xiaojun JIN2(), Xiaoxu GUO1(), Zhonghe JIN2()   

  1. 1 Micro-Satellite Research Center, Zhejiang University, Hangzhou 310027, China
    2 School of Aeronautics and Astronautics, Zhejiang University, Hangzhou 310027, China
  • Received:2020-03-22 Online:2021-06-18 Published:2021-07-26
  • Contact: Zhaobin XU E-mail:zhuyaowei@zju.edu.cn;zjuxzb@zju.edu.cn;axemaster@zju.edu.cn;guoxx@zju.edu.cn;jinzh@zju.edu.cn
  • About author:|ZHU Yaowei was born in 1993. He received his B.E. degree from Huazhong University of Science and Technology in 2016. Now, he is a Ph.D. candidate of the Micro-Satellite Research Center, Zhejiang University. His research interests include inter-satellite ranging, time synchronization and communication, as well as constellation networking. E-mail: zhuyaowei@zju.edu.cn||XU Zhaobin was born in 1984. He received his B.E. and Ph.D. degrees from Zhejiang University in 2008 and 2013, respectively. Now he is an associate researcher of Zhejiang University. He has joined in the Micro-satellite Research Center since he was a graduate student. His research interests include micro-satellite transponder technology, inter-satellite ranging, time synchronization and communication, navigation of micro-satellite formation flying, and constellation networking. E-mail: zjuxzb@zju.edu.cn||JIN Xiaojun was born in 1977. He received his B.E., M.E. and Ph.D. degrees from Zhejiang University in 2001, 2004 and 2007, respectively. He joined the faculty of Zhejiang University in 2009 and has been an associate professor since 2010. Now he is also a Ph.D. supervisor. His research interests include micro-satellite transponder technology, inter-satellite ranging, time synchronization and communication, and navigation of micro-satellite formation flying. E-mail: axemaster@zju.edu.cn||GUO Xiaoxu was born in 1997. He received his B.E. degree from Harbin Institute of Technology in 2019. Now he is a Ph.D. candidate of the Mirco-Satellite Research Center, Zhejiang University. His research interests include inter-satellite communication, spread spectrum measurement and control, as well as transponder. E-mail: guoxx@zju.edu.cn||JIN Zhonghe was born in 1970. He received his Ph.D. degree from Zhejiang University in 1998. Now he is a professor with the School of Aeronautics and Astronautics, Zhejiang University. His research interests include micro-satellite and formation technology, MEMS, inter-satellite communication and measurement technology. E-mail: jinzh@zju.edu.cn
  • Supported by:
    This work was supported by the National Natural Science Foundation of China (61401389)

Abstract:

The advancement of small satellites is promoting the development of distributed satellite systems, and for the latter, it is essential to coordinate the spatial and temporal relations between mutually visible satellites. By now, dual one-way ranging (DOWR) and two-way time transfer (TWTT) are generally integrated in the same software and hardware system to meet the limitations of small satellites in terms of size, weight and power (SWaP) consumption. However, studies show that pseudo-noise regenerative ranging (PNRR) performs better than DOWR if some advanced implementation technologies are employed. Besides, PNRR has no requirement on time synchronization. To apply PNRR to small satellites, and meanwhile, meet the demand for time difference measurement, we propose the round-way time difference measurement, which can be combined with PNRR to form a new integrated system without exceeding the limits of SWaP. The new integrated system can provide distributed small satellite systems with on-orbit high-accuracy and high-precision distance measurement and time difference measurement in real time. Experimental results show that the precision of ranging is about 1.94 cm, and that of time difference measurement is about 78.4 ps, at the signal to noise ratio of 80 dBHz.

Key words: time difference measurement, time synchronization, inter-satellite ranging, satellite formation autonomous flying