Delegates to the World Radiocommunication Conference (WRC) under way this month in Geneva approved a slice of radio frequency spectrum accommodating aircraft-to-satellite position reporting, a move that supports global aircraft tracking. The spectrum allocation responds to international concern over the March 2014 disappearance of Malaysian Airlines Flight MH370, said the International Telecommunications Union (ITU), the organization hosting the conference.
The conference set aside the 1087.7-1092.3 MHz frequency band for Earth-to-space reception by satellites of automatic dependent surveillance-broadcast (ADS-B) position reports from aircraft. The band is currently used for the transmission of ADS-B signals from aircraft to ground stations within their line of sight. Extending it to satellites facilitates beyond line-of-sight position reporting by aircraft, including over oceanic, polar and other remote areas.
The Geneva-based ITU is a United Nations agency that coordinates the international use of radio frequency spectrum. Representatives of more than 160 nations are participating in WRC 2015, which runs from November 2 through November 27. The International Civil Aviation Organization (ICAO), also a U.N. agency, is responsible for developing the standards and performance criteria that aircraft operators will follow to participate in a global tracking system.
After the disappearance of MH370, a Boeing 777-200 that departed from Kuala Lumpur with 239 passengers and crew on board, Malaysia’s minister for communications and later ICAO urged the ITU to provide the necessary radio frequency spectrum for global aircraft tracking. “In reaching this agreement at WRC-15, ITU has responded in record time to the expectations of the global community on the major issue concerning global flight tracking,” ITU Secretary-General Houlin Zhao said November 11. “ITU will continue to make every effort to improve flight tracking for civil aviation.”
The WRC spectrum allocation amounts to an endorsement of the space-based ADS-B business model of Aireon, a joint venture of satellite company Iridium Communications and air navigation service providers Nav Canada, ENAV of Italy, Naviair of Denmark and the Irish Aviation Authority. Aireon is building an air traffic surveillance system that will use ADS-B receivers contained as hosted payloads on the new generation of Iridium Next satellites. Nav Canada will acquire a 51-percent interest in the venture by late 2017.
“Space-based ADS-B is a game-changing development for the international aviation industry,” said John Crichton, Nav Canada president and CEO. “The ITU decision to provide the necessary spectrum allocation enables us to move forward on this important technology. We look forward to implementing space-based ADS-B in our airspace and to the safety and efficiency benefits it will bring for our customers and global aviation.”
Aireon plans to inaugurate the surveillance system in 2017, and it has promised to provide an emergency tracking system free of charge. However, those plans depend on Iridium successfully launching its second-generation constellation of 66 operational mobile communications satellites, in addition to six on-orbit spares and nine ground backup spacecraft.
On October 29, Iridium announced that it has pushed back the launch date of the first two satellites by four months to next April, citing a revised delivery schedule from satellite supplier Thales Alenia Space. The satellite manufacturer has encountered technical issues with a Ka-band communications payload that will fly on the new satellites, Spaceflight Now reported.