Garmin 60csx 业主指南

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he Wide Area Augmentation System (WAAS) is an 

FAA funded service to improve the overall integrity 

of the GPS signal for users in North America. The 

European version of WAAS is referred to as EGNOS.
The system is made up of satellites and approximately 

25 ground reference stations positioned across the 

United States that monitor GPS satellite 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 Web site, testing of WAAS in 

September 2002 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 and EGNOS are is just two service providers 

that adhere 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 that broadcast integrity 

information and differential correction data as 

transmitted by ground reference stations. 
All SBAS systems use the same receiver frequency; 

therefore any operational SBAS system should be 

capable of providing your GPS unit with increased 

accuracy at any location in the world.
Currently, enabling WAAS on your GPSMAP 60CSx 

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. To enable or disable WAAS,see page xx.
 For more information, go to http://gps.faa.gov/

Programs/WAAS/waas.htm.