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What is WAAS?


Welcome everyone!!!
You ask yourself ...what is WAAS?
WAAS stands for Wide Area Augmentation System. It's a system of satellites and ground stations that provide GPS signal corrections, giving position accuracy up to five times better. A WAAS-capable receiver can give you a position accuracy of better than three meters, 95 percent of the time. You don't have to purchase additional receiving equipment or pay service fees to use WAAS.
More on this topic can be found at

For the europeans:

Egnos is available since october 1st:

--- Quote ---This is a major milestone for the project: its primary service is now available to all users equipped with EGNOS-compatible receivers. Most mass-market satellite navigation receivers being sold today are ready for EGNOS.
--- End quote ---

The Wide Area Augmentation System (WAAS) is an air navigation aid developed by the Federal Aviation Administration to augment the Global Positioning System  (GPS), 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.[

The Wide Area Augmentation System is an FAA-funded project to improve the overall integrity of the GPS signal and increase position accuracy for users in North America.

The system is made up of satellites and approximately 25 ground reference stations positioned across the United States that monitor GPS data. Two master stations, located on either coast, collect data from the reference stations and create a GPS data correction message.

According to the FAA's website, testing in 9/2002 of WAAS confirmed an accuracy performance of 1-2 meters horizontal and 2-3 meters vertical throughout the majority of the continental United States and portions of Alaska.

WAAS is just one service provider that adheres to the MOPS (Minimum Operational Performance Standard) for global Satellite Based Augmentation Systems (SBAS). Eventually, there will be several services of worldwide geostationary communication satellites and ground reference stations.

Currently, enabling WAAS on your Garmin GPSMAP in regions that are not supported by ground stations may not improve accuracy, even when receiving signals from an SBAS satellite. In fact it can degrade the accuracy to less than that provided by GPS satellites alone. For this reason, when you enable WAAS on your Garmin GPS receiver, the receiver automatically uses the method that achieves the best accuracy.

For more information, go to

This was quoted straight from page 109 in the Garmin GPS 276C manual. Where I'm located, I've disabled WAAS and the acquisition time and reliability of the GPS has improved, coincidence or not.

That's the official word from Garmin though about (MakMan)


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