Advantages of TDMA and satellite-switched TDMA in Intelsat V and VI

A cost model based on counting the number of up- and down-conversion chains for TDMA and FDMA is presented. From this model, the number of stations for which TDMA implementation costs become lower than those for FDMA is determined. The model is applied to a single-earth-coverage-beam system, to the Intelsat multiple-beam system with static connections, and to the Intelsat VI multiple-beam system with either static or dynamically switched connections. It is shown that dynamically switched TDMA will provide enhanced beam-to-beam connectivity, allow adjustment of beam-to-beam traffic capacity in increments of a single-voice channel, and permit the TDMA network to operate with two rather than four reference stations in each ocean region.