Garmin gpsmap 96 Manuale Utente

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The Wide Area Augmentation System (WAAS) is 

an F.A.A. funded project to improve the overall 

integrity of the GPS signal. It is a space-based system 

that broadcasts integrity information and correction 

data as determined by ground reference stations (see 

DGPS below).  At this time the system is still in the 

developmental stage with a goal of providing reliable 

signals with an accuracy of 7 meters (21-22 ft.) both 

horizontally and vertically 95% of the time. Current 

tests have shown the actual accuracy to be on the 

order of 2-3 meters. For more information, Go To  

http://gps.faa.gov/Programs/WAAS/waas.htm.

The U.S. and Canadian governments (among others) 

have set up Differential GPS (DGPS) stations to 

transmit correction signals. They are operational in 

coastal areas and on many navigable river systems. 

The DGPS system is available for use without fee. 

In addition to compensating for errors in position, 

these corrections signals can also correct for 

deliberate degradation of the accuracy of GPS  by 

the U.S. Department of Defense under their Selective 

Availability (SA) program. 
Refer to the U.S. Coast Guard’s web site: http://www.

navcen.uscg.gov/ for locations and the status of the 

differential sites. Using DGPS requires additional 

equipment.

(Position Format List with Loran TD selected.)