Raymarine RAYSTAR 120 - Chapter 1: Introduction; 1.1 Satellite Differential System

Chapter 1: Introduction 1-1
Chapter 1: Introduction
1.1 Satellite Differential System
The Raystar 120 Satellite Differential GPS Receiver utilizes a new
satellite differential system to improve the accuracy, integrity and
availability of the basic GPS signals, resulting in satellite differential
correctionsand enhanced positionalaccuracy over standard GPS
receivers. Three separate compatible systems currently exist or are
being developed:
1. Wide Area Augmentation System (WAAS). Developed by the
FederalAviation Administration (FAA).
2. European Geostationary Navigation Overlay System
(EGNOS). This system is being developed by a European con-
sortium.
3. The MTSATSatellite-Based Augmentation System (MSAS).
This is being developed by the Japan Civil Aviation Bureau
(JCAB) for civil aviation use.
The area coverage of theWAAS system is thefurthest advanced so
farand includesthe entireUnited States of America but also covers
large areas outsideof this as shown in Figure 1-1 .
Figure 1-1: WAAS Coverage Map
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0˚15˚W30˚W45˚W60˚W90˚W 75˚W105˚W120˚W135˚W150˚W165˚W 15˚E135˚E 150˚E 165˚E 180˚
81170_2.BOOK Page 1 Thursday, July 19, 2001 2:36 PM