TDMA Network Time Synchronization and Navigation Using DGPS

TDMA structure has been implemented in many communication systems to allow multiple users to access. Proper system operation requires all users to have precise knowledge of system time. With pseudo noise (PN) spreading techniques, there are accurate time of arrival (TOA) measurements between the transmitting terminals. The Global Positioning System (GPS) is a satellite navigation system capable of providing continuous worldwide navigation and time dissemination of unprecedented accuracy. GPS uses satellites transmitting PN spread signals to measure TOA from the transmitting satellites to the receiving GPS terminals. This paper presents the design of an integrated time synchronization and navigation filter which is capable of exploiting TOA measurements in TDMA network with DGPS measurements. A TDMA simulation platform is designed based on OPNET. Benefits of the integrated solution are discussed. Stability and performance improvement of the filter are also analyzed. Simulation results show that this solution can provide significant time synchronization and navigation performance benefits