Internal Time and Phase Synchronization for Distributed Micro-Satellite SAR

Tight synchronization among micro-satellites is one of key technical requirement for distributed micro-satellite SAR (DMS). Currently, time and phase synchronization solutions are considered separately. This paper first discusses influence of SAR caused by time and phase skew, and dictates requirements of synchronization for DMS. Then an integrative solution of time and phase synchronization is proposed with phase lock loop (PLL) and two-way time transfer. Based on micro-satellite architecture, the solution chooses to design individual transceiver, and implements time synchronization of the onboard computer (OBC) instead of effective load radar transceiver, which will facilitate the implementation of global command and data handling (C&DH) system schedules for DMS. Its internal synchronization characteristic also guarantees autonomy and robust of synchronization of DMS

[1]  Flaviu Cristian.  A probabilistic approach to distributed clock synchronization , 1989, [1989] Proceedings. The 9th International Conference on Distributed Computing Systems.

[2]  Anthony Skjellum,et al.  A fine-grain clock synchronization mechanism for Myrinet clusters , 2002, 27th Annual IEEE Conference on Local Computer Networks, 2002. Proceedings. LCN 2002..

[3]  Didier Massonnet,et al.  EES-1 internal clock drift measured by interferometry , 1995 .

[4]  Parameswaran Ramanathan,et al.  Transmission Delays in Hardware Clock Synchronization , 1988, IEEE Trans. Computers.

[5]  D. Kirchner,et al.  Two-way time transfer via communication satellites , 1991, Proc. IEEE.

[6]  Maurice Martin,et al.  TechSat 21 and Revolutionizing Space Missions using Microsatellites , 2001 .

[7]  C. Thomas,et al.  GPS time transfer , 1991 .