UGPS Lost Sync

Curious if anyone else has experienced UGPS losing sync and essentially taking a site down since customers can't connect without sync?

We've been running 450M and 450i radios for about two years now and this is the first time we've had this happen. The techs rebooted the injectors and all the radios (5) and sync returned and everything recovered. Is this a canary in the coal mine moment that we have something starting to fail in either injector or UGPS? I can't think of any other component that would cause this to be an issue.

I have forwarded this to our support and development teams.

Almost same scenario here.  Been running for a while now and just started getting this, seemingly random GPS loss.  Doesnt appear to be any rhyme nore reason to which ones are affected ....

Interesting. This is a mixed site where we were testing throughput with some of the upgrades.

  • 2 450Ms on
  • 1 450M on 16.0.1
  • 2 450i's on 16.0.1


  If your APs are configured for "Autosync+Free Run" then they will continue to transmit during this event. (The "+ Free Run" is key.) It will of course cause self-interference if the APs do not have enough guard band between the offending AP(s) without sync and those with sync.

As you continue to troubleshoot this may be preferable though to avoid extensive outages with customers.

...just a thought.



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I have been experiencing this issue on a few AP's that were upgraded to 16.1 just recently. All of these are PMP450i 900 MHz AP's receiving sync from a uGPS. A reboot resolves the issue most of the time but definitely seems to be a software bug with 16.1. Occasionally we need to turn off Aux port power to cycle the uGPS if a reboot of the AP does not restore sync.

We are going to tuck this away for a last minute option if we can't get a tech out to fix the site or a remote reboot doesn't work, but we really don't want that drift.

We are finding so many issues running the newer firmware we are testing rolling back to 15.1.5 for stability and user experience. While we want to use the latest firmware there just seems to be issues coming up that we can't prove to Cambium no matter how hard we work with support on pulling tech files and gathering information.

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We just experienced the same issue on two of our clusters twice in one week. Its a first for us and we have been running 16.0.1 since it came out. I take it 16.1 probably wont help?

Same here I had a site with over 300 subs drop because the cmm5 that was syncing the other aps lost sync we fell apart. 

Tech rolled onsite, all he did was unplug the uGPS, plug it back in and services came up. 

That's what we have had to do. I can't think of any command or option, but is there anyway to power cycle a GPS remotely?