Product Manual

default NMEA settings will work for most GPS applications trying to

display common GPS information (e.g. position, velocity, direction).

DGPS Tab

Differential GPS (DGPS)

positioning involves subtracting a

combination of ranges measured to

various satellites from two or more

receivers measuring the same

satellites simultaneously. When the

signals are subtracted, the major

error sources cancel each other out.

The GPS receiver used with SatViewer can provide DGPS through the

Satellite Based Augmentation System (SBAS), which uses multiple ground

stations and then broadcasts corrections to the end users via SBAS satellites.

Usage: configures the DGPS requirements as follows:

• Auto: will use DGPS when available, but continue to provide autonomous

(uncorrected) positions when DGPS is not available.

• DGPS Required: will only provide positions when DGPS is available.

Autonomous positions will not be available. When DGPS data is available,

it can be applied to your GPS position to increase the accuracy of your

position reading.

• Ignored: will not provide DGPS positions even when available.

NOTE: Due to the limited number and availability of SBAS satellites in the

sky, DGPS coverage from SBAS satellites may not always be available.

Therefore, it is recommended that you use the Auto setting where the GPS

will use and apply DGPS data when available, but will continue providing

positions even when DGPS is not available.

Type: allows you to select SBAS ON or SBAS OFF. (Currently SBAS is the

only DGPS service available, but other DGPS systems may be available in the

future.)

SBAS Sat. PRN: configures which SBAS satellite to use. Selecting Auto

instructs the GPS receiver to automatically make the selection.

Return to Default Settings: If connected to the unit’s GPS receiver, the

following settings are changed and applied to your

unit’s GPS receiver:

• Restores DGPS settings back to default state:

o Usage: Auto

o Type: SBAS ON