Loss of Power/Sensitivity

[rkelly1]

No, not talking about husbands or politicians ;)

Unrelated to switches. Do ubnt radios (radios in general) or sector panels lose sensitivity or output power over time?

I have a Rocket m900 sector unit that seems to be slowly sucking across all freq. No interference or airview issues. Over the past year its signals and qos have slowly decreased. No cps have been added in this time. Same thing on a Rocket M2 UBNT Sector - jitter sllwly got worse, perf decreased over time. On this one we replaced all 3 rockets in the cluster and BAM, back to normal. They had been up for 1.5 years.

The concept has been floating around in my head so i thought id ask here.

[sirhc]

A radio can lose Rx sensitivity if it is picking up a signal that is too strong, usually anything stronger than -40dB is bad even if the signal in not in the channel that it is using.

This is why I used to stand on my soap box and promote RF Armor because UBNT sectors or radios would see their neighbor at -10 dB without the use of shield kits and even though this signal was in a different non overlapping channel the radio still heard it.

This is especially bad on radios that employ an LNA (low noise amplifier) such as any of the airFIBER radios but I did not make shield kits for them.

Usually with RF Armor Sector Kits 5 GHz sectors right beside each other only saw their neighbor radios at -50 dB +/- 10 dB.

[rebelwireless]

That's an excellent point Chris, that no one seems to say often enough. Overdriving the receive elements is when ANY channel (that isn't somehow filtered) is over the radio's threshold (-40ish), not just the channel the radio is listening on.

[lligetfa]

I know RX deafness was an issue back in the days of their modular PCI radios but they claim it to not be an issue with the modern kit. Matt and WHT liked to bring out the wall of RF pic whenever the topic came up.

Active Denial System.jpg (282.32 KiB) Viewed 17450 times

[sirhc]

Yea and those devices are NOT actually doing anything of value. Can you hang 100 devices on the wall and power them up and go to their UI sure but try having them connect and do anything of real value is another story.

Look radios BLEED into the next channel and when radios are close by each other that little tiny BLEED is LOUD.

How can a manufacturer tell you that your over driving your signal turn down the power in the same breath say that a radio sitting right next to it YELLING in its neighbors ears when the neighbor is trying to hear a whisper from 5 miles away? - LUNACY

If your radio hears any signal louder than -40dB not just the one it is listening to that is not good!!!

[rebelwireless]

...and batteries don't have memory anymore either...

That wall looks neat, but how long was that run for? What happens a year in?

[LRL]

I know RX deafness was an issue back in the days of their modular PCI radios but they claim it to not be an issue with the modern kit. Matt and WHT liked to bring out the wall of RF pic whenever the topic came up.

Active Denial System.jpg

That picture makes we want to break out the tinfoil hat!

[josh]

Many radio manufacturers of licensed links these days recommend signals engineered in the -40's, where you can do it. I have heard SAF's newer integras can run into the -30's and be fine.