| This paper addresses key issues in design and implementation of Ka/Ku dual-band SATCOM on-the-move (SOTM) terminals for military applications. Space segment resources include (i) military Ka band and flexibility to extend into commercial Ka band and (ii) commercial Ku band. One example of such an application includes Mounted Battle Command on the Move (MBCOTM). SOTM antennae size has to be selected for performance, SWAP and cost reasons. The paper addresses the trade-off analyses for determining the smallest Ka/Ku dual-band SOTM antennae size that meets the minimum specific acceptable performance requirements. Of these trades, the most important is providing SOTM antennae size and associated Ka-/Ku-band equipment that best meet the performance using military and commercial space resources anywhere in the world. Performance trade-off issues include transponder resources utilization, the cost of equipment, overall system throughput, and network QOS. Ka-band equipment must ensure acceptable full-duplex performance in both mesh and hub-spoke mode in various global rain region categories. Ku-band equipment must support specific data rates in hub-spoke mode. Dual-band system performance may include capability to receive GBS. Analyses presented include these:
1. Upper limit on SOTM antenna size is driven by mobility, acceptable visual profile and SWaP
2. Lower limit on SOTM antenna size is driven by
-Elevation angle and blockage
-Link availability and QOS
-Fade margins
-FCC /ITU uplink compliance
-Adjacent spacecraft interference in Ku band and innovative mitigations such as “Interference Multiple Access Communications”
3. OTM Factors
-Single-reflector SOTM antenna with switchable feeds and RF electronics
-Suitability for commercial Ka bands using the same equipment
-Employment of a wide range of SATCOM waveforms
-User throughput, interoperability and integration
-Maximum transmit power
-Pointing errors
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