Improving satellite bandwidth utilization by applying combinatorial optimization 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 legacy SATCOM waveforms. To overcome some of the limitations of statically defined user communications (UCOM) services in MILSTD-188-183A, the flexibility to assign services nearly anywhere within a frame was introduced in MIL-STD-188-183B. An unfortunate side effect of the enhanced flexibility in slot placement is the increased tendency of the service layout, both within and across channels, to become increasingly fragmented as terminals request the allocation, relocation, and deallocation of UCOM services. Fortunately, by utilizing the innovative service update feature it becomes possible for the IW network management system (NMS) to defragment the service layout of all satellite channels under its control to create larger contiguous regions of unallocated channel space which can be used to accommodate current and future service allocation requests. This paper will discuss the application of combinatorial optimization in the initial allocation and dynamic defragmentation of services within an IW communications system to improve the utilization of satellite bandwidth while minimizing the impact to ongoing user communications.