Lots of 1-5 second drops

I have a customer who is reporting several drops in service ranging from 1 - 5 seconds. Under most conditons this short period would not be any issue but while on Skype or streaming music it is quite noticable.  He is on an ePMP 1000 AP using a force 180 SM, less than a 1/4 mile from the sector. Clear line of sight. The drops are very very random. Rainy days, clear days. Evenings, mornings afternoons. Some day 2 or 3 a day. Other days 10-15.  The frequency we are using is 5820 on this particular link. Kind of wondering if anyone out there has seen this same thing happen and what could be causing it, and is it fixable?  We have tried different SM's and routers. Same results. Thanks all

What's the clients SnR? Have you used eDetect to see if there's any WiFi-based radios that are in the vacinity? Can you try moving to another channel temporarily? Lastly, what firmare revision are you using on AP and SM?

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Hi Jonathan,

In general it looks like bursty interference appears on your channel from time to time.

Once we had almost the same issue with disconnects which appeared spontaneously and have spent several weeks trying to find out root cause.
Then we accidentally discovered that it was caused by microvawe oven radiation.
But it was on 2.4 GHz devices and 5 GHz is not used in microvawe ovens.

You can try to run spectrum analyzer and wait for several hours.
It can help you to detect interferer.

Thank you.

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Running Spectrum Analysis may not help since the AP will be active serving the other customers and from the F180 it will look like noise. The AP is only a 1/4 of a mile away.

Trying to change frequency at the AP could be a good test but I do not know if

-there are other noise-free channels in your area

-a change in the channel may affect clients who are now operating without any issues

- downtime due to AP spectrum analysis before you shift to another channel

I think that the safer approach would be to change the  F180 with a F200 which has

-a narrower main lobe 

- better side lobes and F/B ratio

And also maybe consider changing the location of the Client equipment on the  roof. Sometimes  a relocation (for example a place with concrete on the side or behind) may save the day.

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Downlink snr is 28. We did run edetect several times and each time it shows no interferers, but I guess that could change during the time frame of one of his drops. I guess I would need to run that for a while if that is possible. 

I forgot to include firmware version info. 3.2 is the FM on both the AP and SM

Are you running a fixed ratio of flexible scheduler? Have you tried setting the management traffic to only use MCS0?

we are running a fixed ratio. I am not sure how or where to change to MCS0, but I can give that a try. 

Also, I did have another AP listed in the preferences panel. The AP is not related to the location so I did just get rid of that AP in case it was looking for that from time to time.  Could that cause an issue?


@jonathanderek wrote:

we are running a fixed ratio. I am not sure how or where to change to MCS0, but I can give that a try. 


I'd try running flexible ratio temporarily. You can change the management traffic rate on the AP's  config, radio area.

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