Application of key integrated waveform features to the specification of the MUOS common air interface (CAI)

The Mobile User Objective System (MUOS) is being developed to meet a continuing Department of Defense (DoD) requirement for mobile unprotected narrowband beyond line-of-sight communications. The MUOS will replace the current UHF Follow-On (UFO) satellite constellation as those satellites reach end-of-life. As part of this effort a new Common Air Interface (CAI) will be developed to standardize the waveform used between MUOS user terminals and the satellite. This paper describes a protocol capable of satisfying the MUOS Operational Requirements Document (ORD) directive to provide a higher quality of service than the current UFO system is capable of providing. This protocol captures key features from the Integrated Waveform, a waveform being developed as a possible future replacement for the two current demand-assigned multiple access (DAMA) waveforms now required for operation over 5-kHz and 25-kHz UHF military satellite channels. The new CAI would greatly simplify the use of UHF satellite communications by automatically locating a control channel, capturing the list of available services, and passively connecting to these services. The new CAI should include a standard medium access control (MAC) protocol layer to allow use of modern communication protocols, and provide standardized protocols for voice and messaging that could be easily extended to systems outside of the MUOS network.