Facet L-Band gets stuck in RTK Float

[nseidle]

An RTK Facet L-Band shows successful decryption of signal (the three prong satellite dish is visible) and RTK Float is achieved, but RTK Fix is not. We've tested some units up to 10 minutes and RTK Fix is not achieved.

We've found two potential causes for this:

1. There was a bug in the GNSS library that may have been preventing PMP messages from being transferred correctly from the NEO-D9S to the ZED-F9P. This was fixed here in the GNSS library. This fix was not in RTK firmware version v3.2 and below.

2. While Point Perfect has nearly 99% up time, there are outages and maintenance down times. Please check the ThingStream status page under the Point Perfect section for your given service area.

[nseidle]

Additionally in v3.3 of the RTK firmware we've implemented a max RTK Fix timeout of 180 seconds. If a RTK Float is entered, but a Fix is not achieved in 180 seconds, the ZED-F9R is reset with a hot start to flush the receiver and attempt RTK Float then Fix again. This setting is modifiable through the debug menu.

v3.3 of the RTK firmware is now using the latest GNSS library with the PMP message fix. We believe this issue has been fixed but please let us know if there are other RTK Float/Fix issues related to L-Band.

[nseidle]

This should be fixed in v3.3 of the RTK firmware. Please let us know if you still see problems.

[RickerL]

Hello, sorry to say we're still seeing an issue that seems like it might be related:

Last Saturday, May 13, all of our in-use Facet L-band units were working well in the field.
Monday morning (May 15), none of our units could achieve RTK fix. 3 units in Reno, NV, and 2 units in western OR. All had the exact same symptoms. All are running ver 3.3 release.
Keys up to date (26 days left at the time), all had clear view of the southern sky for multiple hours. Repeated power cycles -- no change.
Single-reticle, no RTK fix, accuracy > 0.3.

I was able to get them all working again by performing factory resets (my PC in Oregon --> Samsung tablet running Teamviewer QuickConnect --> Serial Bluetooth terminal).
It seems like when they were 'provisioned', and got new keys was the point when they started being able to get RTK fix again. New keys came in saying 61 days until expiration.

Here are a few serial terminal screenshots.
This is before factory reset. Notice that it says both keys good, and corrections received. 12.62 Eb/N0, but no RTK fix.

Also before factory reset

After factory reset

[nseidle]

Hi @RickerL - Welcome! And thanks for creating such a nice report.

I'm sorry all five units went down!

It seems like when they were 'provisioned', and got new keys was the point when they started being able to get RTK fix again. New keys came in saying 61 days until expiration.

I'm glad you got a fix in the field.

I started re-testing L-Band lock and I'm seeing failures of infinite float, just as you describe. We'll start digging in.

[nseidle]

A fix for this has been added to the latest v3.6 release.