Review of antenna technologies for very high frequency Data Exchange Systems

The Automated Identification System (AIS) was originally developed as a terrestrial system tracking vessels near the coastline. Dedicated channels were allocated within the spectrum historically reserved for maritime applications in the very high frequency (VHF) band, enabling long range communications, up to a few kilometers. There have been various initiatives in the last decade that extended this system with a space segment, enabling global monitoring of vessels beyond the range of terrestrial stations. Recently, the World Radiocommunication Conference has allocated frequencies for the extension of this system to a two-way VHF Data Exchange System (VDES) via satellite. This requires to adapt spaceborne antenna solutions previously developed for AIS, particularly for missions using small satellites and CubeSats. This paper provides a timely review of existing VHF antenna solutions and new concepts under development which could be applicable to VDES missions. Some key metrics are identified to provide a comparative study between various candidate solutions. Considering the range of possible missions, from secondary payloads on-board larger satellites to dedicated constellations, it is believed that a number of antenna products can find application in future VDES space-based infrastructure.