LEO Satellite Time Synchronization Architecture

A GPS-based time synchronization technique employing a refined HW circuitry and SW algorithm is considered as fine time-management system for Low Earth Orbit (LEO) remote sensing satellites. By synchronizing the On-Board Time (OBT) within satellites to the GPS 1PPS, a very expensive, highly accurate on-board clock is not required to determine the precise on-board time management. Also, the satellite command generation in ground stations and post- processing of earth observation data which a particular image is acquired. This paper analyses on-orbit verification of the existing satellite time sync architecture and presents a new time sync architecture, operation and relation between the OBT and the GPS time.