Technology Assessment for Future MILSATCOM Systems: The EHF Bands.

摘要

Severe crowding of the radio frequency spectrum and of the geostationary orbital arc, coupled with DoD requirements for increased bandwidth, motivate a transition of future MILSATCOM systems to operating frequencies between 20 and 50 GHz (EHF). The identification of potential users, the frequency selection process and the transitional architecture are the focus of DCA/MSO studies. This report, prepared in support of the DCA/MSO Frequency Selection Working Group, assesses the technology necessary to support MILSATCOM evolution to EHF. The technology assessment delineates the present, near term (3-5 years) and far term (6-10 years) availabilities of the major MILSATCOM subsystems. The major subsystems and systemic requirements are derived from strawman systems defined by the DCA/MSO Frequency Selection Working Group. The specific subsystems assessed include low-noise receivers, RF power amplifiers and antennas for the space and ground segments. The antenna gain limitations at EHF imposed by antenna surface accuracy and tracking accuracy are also addressed. As rain attenuation at EHF impacts system design and technology requirements, a global rain attenuation model is presented and the related issues of system availability, duration and impact of rain outages, and site diversity are assessed. Finally, recommendations are presented for technology development efforts and further studies necessary to support future EHF MILSATCOM deployment. (Author)