Technical Characteristics and Regulatory Challenges of Communications Satellite Earth Stations on Moving Platforms

37 INTRODUCTION In recent years, owing to the growing user demand for on-the-move global broadband communications, a new type of satellite terminal has emerged, known as Earth stations on moving platforms (ESOMPs). ESOMP terminals use small antennas with tracking systems and advanced modulation and coding schemes that allow them to provide two-way, high-speed communications from aircraft, maritime vessels, trains, or land vehicles. Various types of satellite terminals have been used onboard vessels (maritime and air) since the 1980s. Initially operating over mobile satellite service (MSS) systems at the L-band, these terminals provided modest narrowband services (voice and low data rates). As verysmall-aperture terminal (VSAT) systems became more established, the next generation of vessel terminals employed parabolic antennas (1.2–2.4 m) and some type of tracking or stabilizing system. They were designed to provide medium data rates over geostationary orbit (GSO) fixed satellite service (FSS) systems operating at the X-, C-, and Ku-frequency bands. New technology capabilities, adopted by satellite designers and terminal equipment manufacturers, have allowed the development of more spectrally efficient, ultra-small terminals that can provide broadband comABSTRACT