10
GPS 17 Installation Guide
U
SING
THE
GPS 17
U
SING
THE
GPS 17
First Time Fix
The first time you turn on your GPS 17, the receiver must be
given an opportunity to collect satellite data and determine
its present position. To ensure proper initialization, the GPS
17 is shipped from the factory in AutoLocate
®
mode, which
allows the receiver to “find itself” anywhere in the world.
When turned on, the GPS 17 searches for satellites. After
it has calculated an initial position fix, the GPS 17 outputs
navigation data. For more information about the data
output by the GPS 17, refer to the
GPS 16/17 Technical
Specifications
located on the Garmin Web site.
WAAS Capability
The GPS 17 can receive WAAS (Wide Area Augmentation
System) satellite signals. WAAS is an FAA-funded project
to improve the overall integrity of the GPS signal and
increase position accuracy for users in North America.
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. Initial
reception of the WAAS signal may take up to 20 minutes.
According to the FAA’s Web site, testing in September 2002
of WAAS 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. For
more information, go to
.
WAAS is just one service provider that adheres to the
minimum operational performance standard for global
Satellite Based Augmentation Systems (SBAS). Eventually,
there will be several services of worldwide geostationary
communication satellites and ground reference stations.
All SBAS systems use the same receiver frequency and are
capable of providing your GPS unit with increased accuracy
at any location in the world.
