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(Created page with "{{Article Infobox2 |Category=WAAS |Title={{PAGENAME}} |Authors=GMV. |Level=Basic |YearOfPublication=2011 |Logo=GMV }} The Wide Area Augmentation System (WAAS) is an GPS Augmenta...")
 
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[[File:FAA WAAS System Overview.jpg|WAAS System|300px|thumb]]
[[File:FAA WAAS System Overview.jpg|WAAS System|300px|thumb]]


The main layers of WAAS architecture are:
The WAAS Ground Segment is composed of multiple Wide-area Reference Stations (WRS). These precisely surveyed ground stations monitor and collect information on the GPS signals, then send their data to three Wide-area Master Stations (WMS) using a terrestrial communications network. The reference stations also monitor signals from WAAS geostationary satellites, providing integrity information regarding them as well. As of October 2008 there were 38 WRSes: twenty in the contiguous United States (CONUS), seven in Alaska, one in Hawaii, one in Puerto Rico, five in Mexico, and four in Canada.<ref name="FAA_WAAS_LAAS">[http://www.navcen.uscg.gov/pdf/cgsicMeetings/47/%5B12%5D%20WAAS-LAAS-CGSIC-07.pdf WAAS and LAAS Status],FAA presentation at 47th meeting of the Civil Global Positioning System Service Interface Committee, September 25, 2008</ref>


*[[Work in Progress:WAAS Ground Segment|WAAS Ground Segment]]:  The ground segment is composed of multiple Wide-area Reference Stations (WRS). These precisely surveyed ground stations monitor and collect information on the GPS signals, then send their data to three Wide-area Master Stations (WMS). Using the data from the WRS sites, the WMSes compute precise differential corrections and integrity bounds, and send them to two pairs of Ground Uplink Stations (GUS), which then transmit to satellites in the Space segment for rebroadcast to the User segment.
Using the data from the WRS sites, the WMSes generate two different sets of corrections: fast and slow. The fast corrections are for errors which are changing rapidly and primarily concern the GPS satellites' instantaneous positions and clock errors. These corrections are considered user position-independent, which means they can be applied instantly by any receiver inside the WAAS broadcast footprint. The slow corrections include long-term ephemeric and clock error estimates, as well as ionospheric delay information. WAAS supplies delay corrections for a number of points (organized in a grid pattern) across the WAAS service area.
 
Once these correction messages are generated, the WMSes send them to two pairs of Ground Uplink Stations (GUS), which then transmit to satellites in the Space segment for rebroadcast to the User segment.
 
==List of reference stations==
 
Each FAA Air Route Traffic Control Center] in the 50 states os U.S. has a WAAS reference station, except for Indianapolis. There are also stations positioned in Canada, Mexico and Puerto Rico.<ref name="FAA_WAAS_LAAS" /> Listed below are the coordinates of the site [[centroid]]s in North America:
 
{| class="wikitable sortable"
! City !! [[ICAO airport code|ICAO]] !! Location !! Elevation
|-
| [[Bethel, Alaska]] || [[Bethel Airport|PABE]] || {{Coord|60.787898226|-161.841705626|region:US_type:landmark|display=inline|name=Bethel, AK - elevation 52.202 m}} || 52.202 m
|-
| [[Billings, Montana]] || [[Billings Logan International Airport|KBIL]] || {{Coord|45.803726761|-108.539727967|region:US_type:landmark|display=inline|name=Billings, MT - elevation 1112.261 m}} || 1112.261 m
|-
| [[Barrow, Alaska]] || [[Wiley Post-Will Rogers Memorial Airport|PABR]] || {{Coord|71.282786134|-156.789914977|region:US_type:landmark|display=inline|name=Barrow, AK - elevation 15.581 m}} || 15.581 m
|-
| [[Cold Bay, Alaska]] || [[Cold Bay Airport|PACD]] ||{{Coord|55.200376531|-162.718528459|region:US_type:landmark|display=inline|name=Cold Bay, AK - elevation 53.652 m}} || 53.652 m
|-
| [[Fairbanks, Alaska]] || [[Fairbanks International Airport|PAFA]] || {{Coord|64.809686817|-147.847403468|region:US_type:landmark|display=inline|name=Fairbanks, AK - elevation 149.888 m}} || 149.888 m
|-
| [[Honolulu, Hawaii]] || [[Honolulu International Airport|PHNL]] || {{Coord|21.312783159|-157.920876933|region:US_type:landmark|display=inline|name=Honolulu, HI - elevation 24.922 m}} || 24.922 m
|-
| [[Juneau, Alaska]] || [[Juneau International Airport|PAJN]] || {{Coord|58.362530123|-134.585495176|region:US_type:landmark|display=inline|name= Juneau, AK - elevation 16.024 m}} || 16.024 m
|-
| [[Mérida, Yucatán]] || [[Manuel Crescencio Rejón International Airport|MMMD]] || {{Coord|20.931919004|-89.662872977|region:US_type:landmark|display=inline|name=Mérida, YUC - elevation 29.157 m}} || 29.157 m
|-
| [[Mexico City]] || [[Mexico City International Airport|MMMX]] || {{Coord|19.431653193|-99.068389463|region:US_type:landmark|display=inline|name=Mexico City, DIF - elevation 2236.638 m}} || 2236.638 m
|-
| [[Puerto Vallarta, Jalisco]] || [[Lic. Gustavo Díaz Ordaz International Airport|MMPR]] || {{Coord|20.679034758|-105.249200735|region:US_type:landmark|display=inline|name=Puerto Vallarta, JAL - elevation 11.077 m}} || 11.077 m
|-
| [[San José del Cabo, Baja California Sur]] || [[Los Cabos International Airport|MMSD]] || {{Coord|23.160416093|-109.717667886|region:US_type:landmark|display=inline|name=San José del Cabo, BCS - elevation 104.286 m}} || 104.286 m
|-
| [[Tapachula, Chiapas]] || [[Tapachula International Airport|MMTP]] || {{Coord|14.791340027|-92.367991216|region:US_type:landmark|display=inline|name=Tapachula, CHP - elevation 54.922 m}} || 54.922 m
|-
| [[Kotzebue, Alaska]] || [[Ralph Wien Memorial Airport|PAOT]] || {{Coord|66.887352636|-162.611355542|region:US_type:landmark|display=inline|name=Kotzebue, AK - elevation 10.911 m}} || 10.911 m
|-
| [[Iqaluit, Nunavut]] || [[Iqaluit Airport|CYFB]] || {{Coord|63.731446844|-68.543393603|region:US_type:landmark|display=inline|name=Iqaluit, NU - elevation 9.998 m}} || 9.998 m
|-
| [[Gander, Newfoundland and Labrador]] || [[Gander International Airport|CYQX]] || {{Coord|48.966447828|-54.597532074|region:US_type:landmark|display=inline|name=Gander, NL - elevation 146.891 m}} || 146.891 m
|-
| [[Winnipeg, Manitoba]] || [[Winnipeg James Armstrong Richardson International Airport|CYWG]] || {{Coord|49.900606898|-97.259280113|region:US_type:landmark|display=inline|name=Winnipeg, MB - elevation 222.046 m}} || 222.046 m
|-
| [[Goose Bay, Newfoundland and Labrador]] || [[CFB Goose Bay|CYYR]] || {{Coord|53.308720955|-60.419401330|region:US_type:landmark|display=inline|name=Goose Bay, NL - elevation 37.842 m}} || 37.842 m
|-
| [[Albuquerque, New Mexico]] || [[Albuquerque Air Route Traffic Control Center|KZAB]] || {{Coord|35.173560874|-106.567308273|region:US_type:landmark|display=inline|name=Albuquerque, NM - elevation 1620.154 m}} || 1620.154 m
|-
| [[Anchorage, Alaska]] || [[Anchorage Air Route Traffic Control Center|PAZA]] || {{Coord|61.229174557|-149.780364869|region:US_type:landmark|display=inline|name=Anchorage, AK - elevation 80.654 m}} || 80.654 m
|-
| [[Aurora, Illinois]] || [[Chicago Air Route Traffic Control Center|KZAU]] || {{Coord|41.782616622|-88.331308050|region:US_type:landmark|display=inline|name=Aurora, IL - elevation 195.922 m}} || 195.922 m
|-
| [[Nashua, New Hampshire]] || [[Boston Air Route Traffic Control Center|KZBW]] || {{Coord|42.735705193|-71.480378445|region:US_type:landmark|display=inline|name=Nashua, NH - elevation 39.141 m}} || 39.141 m
|-
| [[Leesburg, Virginia]] || [[Washington Air Route Traffic Control Center|KZDC]] || {{Coord|39.101556058|-77.542750106|region:US_type:landmark|display=inline|name=Leesburg, VA - elevation 80.085 m}} || 80.085 m
|-
| [[Longmont, Colorado]] || KZDV || {{Coord|40.187286655|-105.127181633|region:US_type:landmark|display=inline|name=Longmont, CO - elevation 1541.389 m}} || 1541.389 m
|-
| [[Fort Worth, Texas]] || [[Fort Worth Air Route Traffic Control Center|KZFW]] || {{Coord|32.830614792|-97.066488376|region:US_type:landmark|display=inline|name=Fort Worth, TX - elevation 155.604 m}} || 155.604 m
|-
| [[Houston, Texas]] || [[Houston Air Route Traffic Control Center|KZHU]] || {{Coord|29.961833882|-95.331462501|region:US_type:landmark|display=inline|name=Houston, TX - elevation 10.947 m}} || 10.947 m
|-
| [[Hilliard, Florida]] || KZJX || {{Coord|30.698824796|-81.908178358|region:US_type:landmark|display=inline|name=Hilliard, FL - elevation 2.141 m}} || 2.141 m
|-
| [[Olathe, Kansas]] || KZKC || {{Coord|38.880140378|-94.790729104|region:US_type:landmark|display=inline|name=Olathe, KS - elevation 305.814 m}} || 305.814 m
|-
| [[Palmdale, California]] || [[Los Angeles Air Route Traffic Control Center|KZLA]] || {{Coord|34.603503189|-118.083872233|region:US_type:landmark|display=inline|name=Palmdale, CA - elevation 763.546 m}} || 763.546 m
|-
| [[Salt Lake City, Utah]] || KZLC || {{Coord|40.786007936|-111.952158417|region:US_type:landmark|display=inline|name=Salt Lake City, UT - elevation 1287.420 m}} || 1287.420 m
|-
| [[Miami, Florida]] || KZMA || {{Coord|25.824644475|-80.319246501|region:US_type:landmark|display=inline|name=Miami, FL - elevation -7.882 m}} || -7.882 m
|-
| [[Memphis, Tennessee]] || KZME || {{Coord|35.067423639|-89.955391700|region:US_type:landmark|display=inline|name=Memphis, TN - elevation 68.788 m}} || 68.788 m
|-
| [[Farmington, Minnesota]] || KZMP || {{Coord|44.637444415|-93.152039309|region:US_type:landmark|display=inline|name=Farmington, MN - elevation 262.667 m}} || 262.667 m
|-
| [[Ronkonkoma, New York]] || [[New York Air Route Traffic Control Center|KZNY]] || {{Coord|40.784293219|-73.097181151|region:US_type:landmark|display=inline|name=Ronkonkoma, NY - elevation 6.108 m}} || 6.108 m
|-
| [[Fremont, California]] || KZOA || {{Coord|37.543019928|-122.015922570|region:US_type:landmark|display=inline|name=Fremont, CA - elevation -3.459 m}} || -3.459 m
|-
| [[Oberlin, Ohio]] || [[Cleveland Air Route Traffic Control Center|KZOB]] || {{Coord|41.297135898|-82.206391657|region:US_type:landmark|display=inline|name=Oberlin, OH - elevation 224.115 m}} || 224.115 m
|-
| [[Auburn, Washington]] || KZSE || {{Coord|47.286919203|-122.188372739|region:US_type:landmark|display=inline|name=Auburn, WA - elevation 82.128 m}} || 82.128 m
|-
| [[San Juan, Puerto Rico]] || TJZS || {{Coord|18.431249167|-65.993480433|region:US_type:landmark|display=inline|name=San Juan, PR - elevation -28.547 m}} || -28.547 m
|-
| [[Hampton, Georgia]] || KZTL || {{Coord|33.379671593|-84.296678124|region:US_type:landmark|display=inline|name=Hampton, GA - elevation 261.142 m}} || 261.142 m
|}





Revision as of 13:52, 16 June 2011


WAASWAAS
Title WAAS Ground Segment
Author(s) GMV.
Level Basic
Year of Publication 2011
Logo GMV.png


The Wide Area Augmentation System (WAAS) is an GPS Augmentation system developed by the Federal Aviation Administration (FAA), with the goal of improving its accuracy, integrity, and availability. Essentially, WAAS is intended to enable aircraft to rely on GPS for all phases of flight, including precision approaches to any airport within its coverage area.

WAAS uses a network of ground-based reference stations, in North America and Hawaii, to measure small variations in the GPS satellites' signals in the western hemisphere. Measurements from the reference stations are routed to master stations, which queue the received Deviation Correction (DC) and send the correction messages to geostationary WAAS satellites in a timely manner (every 5 seconds or better). Those satellites broadcast the correction messages back to Earth, where WAAS-enabled GPS receivers use the corrections while computing their positions to improve accuracy.[1]

WAAS Ground Segment

WAAS System

The WAAS Ground Segment is composed of multiple Wide-area Reference Stations (WRS). These precisely surveyed ground stations monitor and collect information on the GPS signals, then send their data to three Wide-area Master Stations (WMS) using a terrestrial communications network. The reference stations also monitor signals from WAAS geostationary satellites, providing integrity information regarding them as well. As of October 2008 there were 38 WRSes: twenty in the contiguous United States (CONUS), seven in Alaska, one in Hawaii, one in Puerto Rico, five in Mexico, and four in Canada.[2]

Using the data from the WRS sites, the WMSes generate two different sets of corrections: fast and slow. The fast corrections are for errors which are changing rapidly and primarily concern the GPS satellites' instantaneous positions and clock errors. These corrections are considered user position-independent, which means they can be applied instantly by any receiver inside the WAAS broadcast footprint. The slow corrections include long-term ephemeric and clock error estimates, as well as ionospheric delay information. WAAS supplies delay corrections for a number of points (organized in a grid pattern) across the WAAS service area.

Once these correction messages are generated, the WMSes send them to two pairs of Ground Uplink Stations (GUS), which then transmit to satellites in the Space segment for rebroadcast to the User segment.

List of reference stations

Each FAA Air Route Traffic Control Center] in the 50 states os U.S. has a WAAS reference station, except for Indianapolis. There are also stations positioned in Canada, Mexico and Puerto Rico.[2] Listed below are the coordinates of the site centroids in North America:

City ICAO Location Elevation
Bethel, Alaska PABE Template:Coord 52.202 m
Billings, Montana KBIL Template:Coord 1112.261 m
Barrow, Alaska PABR Template:Coord 15.581 m
Cold Bay, Alaska PACD Template:Coord 53.652 m
Fairbanks, Alaska PAFA Template:Coord 149.888 m
Honolulu, Hawaii PHNL Template:Coord 24.922 m
Juneau, Alaska PAJN Template:Coord 16.024 m
Mérida, Yucatán MMMD Template:Coord 29.157 m
Mexico City MMMX Template:Coord 2236.638 m
Puerto Vallarta, Jalisco MMPR Template:Coord 11.077 m
San José del Cabo, Baja California Sur MMSD Template:Coord 104.286 m
Tapachula, Chiapas MMTP Template:Coord 54.922 m
Kotzebue, Alaska PAOT Template:Coord 10.911 m
Iqaluit, Nunavut CYFB Template:Coord 9.998 m
Gander, Newfoundland and Labrador CYQX Template:Coord 146.891 m
Winnipeg, Manitoba CYWG Template:Coord 222.046 m
Goose Bay, Newfoundland and Labrador CYYR Template:Coord 37.842 m
Albuquerque, New Mexico KZAB Template:Coord 1620.154 m
Anchorage, Alaska PAZA Template:Coord 80.654 m
Aurora, Illinois KZAU Template:Coord 195.922 m
Nashua, New Hampshire KZBW Template:Coord 39.141 m
Leesburg, Virginia KZDC Template:Coord 80.085 m
Longmont, Colorado KZDV Template:Coord 1541.389 m
Fort Worth, Texas KZFW Template:Coord 155.604 m
Houston, Texas KZHU Template:Coord 10.947 m
Hilliard, Florida KZJX Template:Coord 2.141 m
Olathe, Kansas KZKC Template:Coord 305.814 m
Palmdale, California KZLA Template:Coord 763.546 m
Salt Lake City, Utah KZLC Template:Coord 1287.420 m
Miami, Florida KZMA Template:Coord -7.882 m
Memphis, Tennessee KZME Template:Coord 68.788 m
Farmington, Minnesota KZMP Template:Coord 262.667 m
Ronkonkoma, New York KZNY Template:Coord 6.108 m
Fremont, California KZOA Template:Coord -3.459 m
Oberlin, Ohio KZOB Template:Coord 224.115 m
Auburn, Washington KZSE Template:Coord 82.128 m
San Juan, Puerto Rico TJZS Template:Coord -28.547 m
Hampton, Georgia KZTL Template:Coord 261.142 m


Notes

References

  1. ^ WAAS in Wikipedia
  2. ^ a b WAAS and LAAS Status,FAA presentation at 47th meeting of the Civil Global Positioning System Service Interface Committee, September 25, 2008