Professor Per Enge
Aeronautics and Astronautics, Stanford University
To facilitate this important trend, the international aviation community is deploying two differential GPS systems called the Wide Area Augmentation System (WAAS) and the Local Area Augmentation System (LAAS). Both systems use high-quality receivers at known locations to develop corrections to the signals from the satellites and to bound the error of the corrected signal. The corrections improve the nominal accuracy (95%) of stand-alone service, and the error bounds guarantee the integrity (10-7) of the approach. LAAS provides the very high accuracy and integrity required to support precision approach operations at our busiest airports. WAAS supports operations over continental areas including precision approach operations at small and medium airports.
At Stanford, we have supported the development of both WAAS and LAAS with research and tests directed at the fundamental error sources, algorithms, safety and operational benefits. In collaboration with the FAA Technical Center (FAATC), we have developed complete prototypes of both systems.
This talk will describe some exciting current applications of GPS to aviation. It will also provide a brief report on the development of WAAS and LAAS in the United States. Next, it will discuss the current challenges that face GPS use for aviation. These include safety analyses and radio frequency interference. Finally, it will describe the long and short term strategies to overcome these challenges.