Raymarine Raystar 120 - Manual (Page 8)

2 Raystar 120 & Raystar 112LP GPS Receivers - Owner’s Handbook
1
Abo
ut SD-GPS
(R
S120
only)
Figure 1-1: The WAAS System
Your Raystar 120 SD-GPS Receiver can then use this correctional data to
refine the GPS positional data it receives. This results in improved
accuracy (typically less than 3 metres) compared with standard GPS
(typically 15 m) or land-based DGPS (typically 10 m).
Availability of WAAS in North America
The area coverage of WAAS includes the entire United States of America
(see Figure 1-2).
Figure 1-2: WAAS Coverage Map
D4903-1
D4910-1
0˚
15˚N
30˚N
45˚N
60˚N
75˚N
15˚S
0˚ 15˚W 30˚W 45˚W 60˚W 90˚W 75˚W 105˚W 120˚W 135˚W 150˚W 165˚W 15˚E 135˚E 150˚E 165˚E 180˚