AbstractThe INTELSAT 120 Mb/s TDMA/DSI system consists of reference stations and traffic terminals which access the INTELSAT V satellites as a multiple beam network. Two reference stations located within each satellite beam serve the network by controlling the acquisition and synchronization of the traffic terminals and by performing TDMA system monitoring. Within the reference stations, the acquisition and synchronization control functions are performed by the reference terminal equipment and the monitoring functions are performed by the TDMA system monitor. This paper provides a discussion of the TDMA system monitor, including its configuration, measurement techniques, and an assessment of its measurement.