Doubling the capacity of a communications satellite system

Two one-way channels are normally used in digital two-way voice communication. Each channel is in effect-used only one half the time. A recent discovery of ours recognized that any one-way channel within a satellite spot-beam can be accessed by anyone in the footprint of the beam. In a two-way voice call, the two parties alternate (in principle) in their transmissions-when one speaks the other is silent. Therefore, the two can share a single one-way channel and provide continuous use of the channel, their respective transmissions interleaved with one another. This condition is unique to intrabeam communication via satellite (or balloon). In a satellite system, capacity is a valued commodity, where capacity is limited by allocated bandwidth and power available. Under those two constraints of bandwidth and power limitation, the discovery described generates a doubling of capacity. This article addresses this concept and some of the engineering challenges and opportunities arising therefrom.