Frequency and slot switching in FDMA/TDMA multiple beam satellite processors

Several next-generation global satellite systems being proposed are based on multiple beam coverage with frequency division multiple access/time division multiple access (FDMA/TDMA) satellite processing. We study the effects on collision probability of adding onboard band and slot switching. A matrix model of the onboard processing is developed that allows evaluation of the probability of collision as a function of activity factor. Results are shown for both uniform and nonuniform probability distributions on the mapping of uplink user beam/band position to downlink beam/band position. We quantify the benefit of the additional onboard switching and show that the cost effectiveness of onboard band and/or slot switching must be carefully evaluated for a particular system design and expected activity factor.