Editing Wide Area Augmentation System (section)

==Future of WAAS==

===Improvement to aviation operations===
In 2007, WAAS vertical guidance was projected to be available nearly all the time (greater than 99%), and its coverage encompasses the full continental U.S., most of Alaska, northern Mexico, and southern Canada.<ref>Federal Aviation Administration. [http://gps.faa.gov/programs/waas/questionsanswers.htm WAAS 200ft Minimum Related Questions and Answers] {{webarchive|url=https://web.archive.org/web/20060925215639/http://gps.faa.gov/programs/waas/questionsanswers.htm |date=2006-09-25 }}. Accessed June 12, 2006.</ref> At that time, the accuracy of WAAS would meet or exceed the requirements for Category 1 [[Instrument Landing System|ILS]] approaches, namely, three-dimensional position information down to 200 feet (60 m) above touchdown zone elevation.<ref name="faa.gov" />

===Software improvements===
Software improvements, to be implemented by September 2008, significantly improve signal availability of vertical guidance throughout the CONUS and Alaska. Area covered by the 95% available LPV solution in Alaska improves from 62% to 86%. And in the CONUS, the 100% availability LPV-200 coverage rises from 48% to 84%, with 100% coverage of the LPV solution.<ref name="WAAS_CGSIC47" />

===Space segment upgrades===
Both Galaxy XV (PRN #135) and Anik F1R (PRN #138) contain an L1 & L5 GPS payload. This means they will potentially be usable with the [[GPS modernization|L5 modernized GPS signals]] when the new signals and receivers become available. With L5, avionics will be able to use a combination of signals to provide the most accurate service possible, thereby increasing availability of the service. These avionics systems will use ionospheric corrections broadcast by WAAS, or self-generated onboard dual frequency corrections, depending on which one is more accurate.<ref name="FAA_GPS_Modern">Federal Aviation Administration (FAA), [http://gps.faa.gov/gpsbasics/GPSmodernization-text.htm GPS Modernization] {{webarchive|url=https://web.archive.org/web/20060926023328/http://gps.faa.gov/GPSbasics/GPSmodernization-text.htm |date=2006-09-26 }} Page. Accessed 29 November 2006.</ref>