SE868-V3 Product User Guide
1VV0301205 r4 – 2016-01-20
Reproduction forbidden without written authorization from Telit Communications S.p.A. - All Rights Reserved.
Page 20 of 76
Mod. 0805 2015-02 Rev.4
This feature is useful for applications in which very low dynamics are not expected, the classic
example being an automotive application.
Static Navigation is disabled by default, but can be enabled by OSP command MID 143.
4.8.
Velocity Dead-Reckoning
Velocity dead-reckoning is the use of the last known velocity to propagate the navigation
solution when there are insufficient measurements to calculate an updated solution. It serves
to mitigate the effects of blocked satellite signals by continuing to provide a position output.
Note
: The receiver outputs status information to indicate that a solution is being maintained
using dead-reckoning.
This feature is disabled by default but can be enabled using the Mode Control message (MID
136). Valid timeout values are in a range from zero (which disables dead-reckoning) to two
minutes.
4.9.
Jamming Rejection – Continuous Wave (CW) Jamming
Mitigation
Continuous Wave (CW) jamming mitigation improves performance in a system that is affected
by these predictable jamming signals:
•
Stable jamming signals generated by your system implementation, such as harmonics
of digital clocks and logic switching
•
Predictable jamming signals in the RF environment (e.g. from collocated transmitters)
When this feature is activated, the process for jamming mitigation is:
1.
Detect jamming signals above the noise floor.
2.
Isolate and filter frequencies containing jamming signals.
The GNSS signal is constantly monitored for CW jammers and up to eight are detected and
cancelled in each band without any operator intervention.
GPS, GLONASS, and BDS band cancellers are activated and reported using OSP Message ID
92. This feature is useful both in the design stage and during the production stage for uncovering
issues related to unexpected jamming. Use OSP MID 220,1 to configure this feature.
