Reducing terminal slot contention by applying set theory to the integrated waveform (DAMA UHF SATCOM)

The integrated waveform (DAMA UHF SATCOM), specified in MIL-STD-188-181C/182B/183B/185A, defines a TDMA communication system in an attempt to improve satellite bandwidth utilization over conventional SATCOM waveforms. To overcome some of the limitations of statically defined user communications (UCOM) services in MIL-STD-188-183A, the flexibility to assign services nearly anywhere within a frame was introduced in MIL-STD-188-183B. Unfortunately, though the flexibility to locate services in nearly any location within a channel has the ability to greatly improve bandwidth utilization, the benefits of this feature have a tendency to be greatly diminished, especially for half-duplex terminals, by limitations attributable to terminal slot contention. Fortunately, through the efficient allocation and relocation of Downlink and Uplink support services, it becomes possible for the IW Network Management System to minimize the system performance impact due to terminal slot contention by allowing the allocation of UCOM services wherever necessary to achieve optimal satellite channel utilization. This paper will discuss the application of set theory to the allocation of downlink and uplink support services within a TDMA communications system to reduce the impact of slot contention and improve the utilization of satellite bandwidth.