E500 Noise Issue

Hi Everyone, I am sending this on behalf of my customer.

Whenever we have a AP broadcasting on Channel 2 on any tower we create this noise effect on several of our other towers.

Even if a weak external SSID is seen on channel 2 we get the same effect.

The Cambiums ponl-mesh-base-lt27 and  ponl-mesh-base-lt20b below are located about 300Meters apart on different wharfs .

We have moved all of our wireless infrastructure to above channel 6 which is not ideal.

Does anyone have any ideas of what could be causing this issue?

Pic 1 Light Tower 27 (Middle/South 5 wharf)

Pic 2 Light Tower 20B (middle of 4 Wharf)

Pic 3 Light Tower 20 (Southern 4 wharf)

Pic 4Light Tower 3 (2 Wharf South)

Pic 5Light Tower 25 (5 Wharf North)

Please correct me if my understading is wrong:

  1. Issue reported
    • Noise level is high on channel 2 even when its coverage area is less overlapped with other APs.
    • Based on description, it seems Mesh link is established between two E500 APs.
  2. Technical Information Required
    • By any chance, did customer monitor noise levels on the same channel using third party devices.
    • Is 5GHz allowed at customer site?
  3. Recommendations

so if you set any e500 AP to channel 2 (2417MHz for 802.11b or 20MHz channel bandwidth 802.11g/n/ac mode) you get a large increase in the noise floor around 2417MHz at the other e500 access points is that correct? 

pic1 and pic2 seems to show a higher noise floor, but 3-5 do not. Have you adjusted the TX power setting for the channel 2 Transmitter? The TX gain setting does have some tolerance (+/- 2dB) and Channel 2 might be on the high-side of that tolerance in some cases. Also, the antenna pattern might be a bit better for that particular channel vs. other channels and give a bit more gain.