SE868Kx-Ax Family Product User Guide
1VV0301201 Rev. 5
Page 19 of 83
2021-07-15
Not Subject to NDA
4.
PRODUCT FEATURES
Built-in Antenna
The module includes a built-in antenna for GPS, Galileo and GLONASS signals. See
section 10.2 GNSS Antenna (included in the module) for constellations supported by each
module.
Multi-Constellation Navigation
(SE868-A and SE868K3-Ax only
)
GPS and GLONASS constellations are enabled by default. BeiDou and Galileo are also
supported. If BeiDou is enabled, GLONASS and Galileo are disabled.
The user may enable or disable constellations via the $PMTK353 command.
Quasi-Zenith Satellite System (QZSS)
The satellites of the Japanese regional system are in a highly inclined, elliptical
geosynchronous orbit, allowing continuous high-elevation coverage over Japan using
only three satellites plus one geostationary satellite. PRNs 193, 194, and 195 are
supported. They provide ranging signals for augmentation of the GPS system
QZSS constellation usage is controlled by the $PMTK352 command and is disabled by
default. NMEA reporting for QZSS may be enabled/disabled by the $PMTK351 command.
Satellite-Based Augmentation System (SBAS)
SBAS is not supported on the current production SE868-AS and SE868K7-Ax modules
(with the enhanced ROM).
The receiver is capable of using SBAS satellites as a source of differential corrections.
These systems (WAAS, EGNOS, GAGAN and MSAS) use geostationary satellites to
transmit signals similar to those of GPS and in the same L1 band.
Enabling SBAS limits the maximum fix rate to 5 Hz. If disabled, the maximum is 10 Hz.
The module is enabled for SBAS by default, but can be disabled by command $PTMK313.
Either SBAS or DGPS corrections can be used and are set by the $PMTK301 command.
4.4.1.
SBAS Corrections
The SBAS satellites transmit a set of differential corrections to their respective regions.
The use of SBAS corrections can improve positioning accuracy.
