PHY 3 & 4 Frequently Collapse


#1

I have a b24 link in trial. It’s not well aligned (the mounts are terrible!) but signal levels are unvaried after a few months of use. We have not experienced any rain fade.

We do experience a pretty frequent collapse of PHY 3 & 4, with 4 suffering most often. I’m taking stats once a minute using Telegraf + InfluxDB & visualising in Grafana as honestly I thought our problem would be rain fade. Anyway, we see this in the short term:

There’s no correlation between increased noise or rain events and the PHY collapses.

Over the longer term, we see this type of event as an orange dip in the PHY. Note how often this happens - below chart is a one-week timescale.

We’ve already shifted to a 50:50 traffic split but that hasn’t done much except increase latency across the link.

Any ideas? Maybe its interference & the noise charts just are not capturing it?

If there’s a new mount with better fine-alignment we can beta test (happy to pay) I’d love to because this one is as bad as circa-2006 Bridgewave brackets and I know there’s more dB in our budget I can claw back.


#2

Hi @Network5,

I’m sorry to hear about your alignment issues with the B24. I understand how frustrating the B24 mount is, since I’ve installed my fair share of units across my network. I have a couple of videos that hopefully will help you with fine tuning your link.

Initial installation and alignment: https://www.youtube.com/watch?v=a0VvIdUpIm8
Fine Tuning: https://www.youtube.com/watch?v=JiSmPHrFiqc&t

When PHY 3 and 4 go away, does the data rate of PHY 1 and 2 increase? In our products, the software tries to get the best data rate possible. Sometimes reducing the chains to three or two improve the overall performance of the radio link. If you’re able to get this link aligned better, I don’t think you’ll see that issue anymore. Also please feel free to come into Mimosa Support chat so we can take a closer look.

As for beta testing of a new mounting bracket, we have been looking at doing some redesign work on it, but don’t have any in-house yet for alpha/beta testing.


#3

Yes, they do. Prior to the event, all four chains are sitting at 260 Mbps each. During the event, PHY 1 & 2 bump up to 346.7 Mbps each. As in the image below.

44

Why am I seeing this without also seeing a decrease in SNR reporting on channels 3 & 4? What’s causing these channels to drop? Is there some debugging we can do, say stream debug messages to a local collector & see why the radio is doing this?


#4

Sorry for the late reply. It could be many things causing this to drop to two streams. I would suggest coming into Support Chat tomorrow so one of my guys can take a look at your radios.