Multilateration system time synchronization via over-determination of TDOA measurements

Sensors of any multilateration system have to be precisely synchronized to achieve accurate position estimation from targets´ TDOA measurements. The GPS common view principle is frequently implemented in Distributed Time systems and on the other hand additional delays with one time reference in Central Time system. Such systems, however, may not operate effectively if the reference time is not available. This paper provides description together with test results of clock synchronization estimated using position over-determination principles applied to TDOA measurements of well-tracked targets in WAM system (Brno, Ostrava and simulated joint system operated by Czech ANS) with a height of about 5 km and higher. Clock correction factors or delays can then be applied to sensor clock signals, providing accurate tracking of targets such as aircraft, even in the event of GPS failure or jamming.