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SYSTEM OVERVIEW
The GP-320B is a GPS receiver with WAAS (Wide Area Augmentation System) capability.
WAAS, available in North America, is a provider in the worldwide SBAS (Satellite Based
Augmentation System) navigation system. CBAS provides GPS signal corrections to SBAS
users, for even better position accuracy, typically better than three meters. There are three more
SBAS providers, MSAS (Multi-Functional Satellite Augmentation System) for Japan, EGNOS
(Euro Geostationary Navigation Overlay Service) for Europe and GAGAN (GPS And GEO
Augmented Navigation) for India. The illustration below shows the coverage area. (Accuracy
may be affected when using a GEO satellite not within your current location.) This manual uses
“WAAS” for these three providers generically.
WAAS
MSAS
EGNOS
GAGAN
Provider
Satellite type
Longitude
Satellite No.
WAAS
Intelsat Galaxy XV
133°W
135
TeleSat Anik F1R
107.3°
138
Inmarsat-4-F3
98°W
133
EGNOS
Inmarsat-3-F2/AOR-E
15.5°W
120
Artemis
21.5°E
124
Inmarsat-4-F2
25°E
126
MSAS
MTSAT-1R
140°E
129
MTSAT-2
145°E
137
GAGAN
Inmarsat-4-F1
64°E
127
