GPS-squitter low-altitude air surveillance in the Gulf of Mexico

Aircraft surveillance in the Gulf of Mexico can be substantially improved at relatively low cost with GPS-Squitter, a form of Automatic Dependent Surveillance Broadcast(ADS-B), with GPS-Squitter, aircraft in the Gulf would use Mode S transponders to automatically broadcast (i.e., squitter) their position (latitude, longitude, and barometric altitude) and identification. An aircraft would determine its position from an onboard positioning system such as GPS (Global Positioning System). To demonstrate the feasibility of GPS-Squitter low-altitude surveillance in the Gulf of Mexico, MIT Lincoln Laboratory, in a cooperative effort with the FAA (Federal Aviation Administration) and industry, conducted a series of tests in the Gulf during November and December 1994. For the tests, three GPS-Squitter ground stations were deployed in the Gulf-two on oil platforms and a third at the Petroleum Helicopters, Inc. (PHI) heliport in Morgan City, Louisiana. The ground stations were used to track three GPS-Squitter-equipped aircraft (two Bell 206 helicopters and Cessna 421); live traffic displays were available in Morgan City, New Orleans, and Houston. This paper describes the configuration of the test vehicles and ground stations. Surveillance performance results are also included for each of the test vehicles.