Using Sbas Data - ashtech DG16 Reference Manual

Using SBAS Data

You can choose from up to five options to specify how to use the SBAS
channel data:
1. Decode and output
2. SBAS-to-RTCM conversion and output
3. Utilization of SBAS corrections in DGPS solution and SBAS-to-RTCM
conversion and output
4. Integrity information utilization
5. Ranging signal utilization in navigation solution
Decoding and Outputting SBAS Data
If the SBAS option is enabled and if the SBAS mode is activated, you can set
the DG16 to decode and output SBAS data using the $PASHS,SBA,DAT
command. The number of SBAS channels used for the decoding and
outputting SBAS data depends on the $PASHS,SBA,CDU settings.
Converting SBAS Correction to RTCM SC-104
The SBAS corrections are converted to RTCM SC-104 format for output. The
RTCM corrections are optimized for the current DG16 location. The
generated RTCM corrections include RTCM message types 1, 2, 3, 6, and 9.
Message Type 3 contains the current Reference Position of the receiver, if in
BASE mode, or the current GPS/DGPS position of the receiver, if in stand-
alone or REMOTE mode.
Use the $PASHS,SBA,RTC command to convert the SBAS corrections to
RTCM SC-104. See $PASHS,SBA,RTC on page 311 for more information.
The number of SBAS channels used for the conversion depends on the $PASHS,SBA,CDU setting.
Utilizing SBAS Corrections in DGPS Solution
The full SBAS set of corrections include:
• fast corrections—Satellite clock corrections
• long term or slow corrections—Satellite ephemeris and long term satellite
clock corrections
• ionosphere corrections
Use the $PASHS,RTC,SBA and $PASHS,RTC,REM,ON commands to utilize
SBAS corrections in the DGPS solution.
SBAS message types 6, 8 and 10 are not used in position computation using
68 DG14 and DG16 Board & Sensor Reference Manual