| 摘要 |
PURPOSE:To prevent a burst step-out during antenna switching by making the corresction from the transmission timing of an in-operation site to that of a stand-by site on the basis of the intrinsic characteristics of diversity communication path difference. CONSTITUTION:When a site A is in operation and a site B is stand-by at a terrestrial station, the transmission timing TB(t) of the stand-by site B is estimated every moment, only by knowing the transmission timing TA(t) of the in-operation site A, according to the correction equation 1, where DELTALe is a difference in propagation time at time te when a satellite is on the equator and H is maximum amplitude of variation due to the track slanting angle of the satellite. Therefore, whenever antenna sites are switched, a synchronizing transmission timing signal is sent out of a clock counting circuit 17-6 to a compression buffer 12B, so a bust step-out during the antenna switching is prevented. |
