Synchronization accuracy and error analysis of open-loop TDMA systems

Error sources encountered in an open-loop TDMA system are analyzed including range measurement, calibration, and computation errors. Based on this analysis, the transmit reference delay and the burst position accuracy are determined. It is shown that in a properly designed open-loop system, TDMA frame synchronization can be maintained to a reasonable accuracy if ranging stations are widely dispersed. If all the station locations are properly calibrated, and satellite Doppler extrapolated, the open-loop synchronization accuracy is expected to be comparable to and, in some cases, better than that of a closed-loop system.