Garmin GPSMAP 188C Sounder - Manual (Page 46)

40 GPSMAP 188/188C Sounder Owner’s Manual
M
AIN
M
ENU
> GPS T
AB
The progress of satellite acquisition is shown in three stages:
• No signal strength bars—the receiver is looking for the
satellites indicated.
• Light signal strength bars—the receiver has found the
satellite(s) and is collecting data.
• Dark signal strength bars—the receiver has collected the
necessary data and the satellite(s) are ready for use.
Sky View
Signal Strength
Bars
Receiver
Status
Differential
Status
Accuracy
DOP
The status field indicates a 2D or 3D, when the GPSMAP
188/188C Sounder has collected the necessary data from satellites
to calculate a fix. The unit then updates the location, date, and time.
You can use the sky view to help determine if any satellites
are being blocked, and whether you have a current location fix
(indicated by a 2D, 2D Differential, 3D, or 3D Differential in
the status field). The sky view shows a bird’s-eye view of the
position of each satellite relative to the receiver’s last known
location. The outer circle represents the horizon (north up), the
inner circle 45º above the horizon, and the center point a position
directly overhead. You can also set the sky view to a Track Up
configuration, causing the top of the sky view to align along your
current track heading.
WAAS Capability
The GPSMAP 188/188C Sounder is capable of receiving WAAS
(Wide Area Augmentation System) satellite signals. WAAS is an
FAA (Federal Aviation Administration) funded project to improve
the overall accuracy and integrity of the GPS signal for aviation
use, but land/sea based users can also benefit from this system. At
this time, the system is still in the development stage and is not
fully operational.
There are currently two WAAS satellites that can be received in the
U.S.A., one over the Atlantic Ocean and one over the Pacific