Handling Process
1. Customer sends the diagnostic file of AC.
2. Check all applied configuration on AC.
3. Asked about the number of AP that have this issue.
Root Cause
After checking the AC configuration we found below:
1. Interference between channels
[AC6605-wlan-regulate-domain-default] dca-channel 2.4g channel-set 1,2,6,9,10,11,13 ---> the distance between these channels nember is very small so it caused interference
Each channel on the 2.4 GHz spectrum is 20 MHz wide. The channel centers are separated by 5 MHz and the entire spectrum is only 100 MHz wide. This means the 11 channels have to squeeze into the 100 MHz available and in the end they overlap.
However, there are three channels that don’t overlap: 1, 6 and 11, as you can see in the image below. Co-channel interference is where devices take turns 'talking', so the more devices on one channel, the longer it takes for a device to talk since it has to wait for its turn.
2. AP minmum power is small as per below.
=====================================================
===============display radio all===============
=====================================================
CH/BW:Channel/Bandwidth
CE:Current EIRP (dBm)
ME:Max EIRP (dBm)
CU:Channel utilization
ST:Status
WM:Working mode (normal/monitor/monitor dual-band-scan)
----------------------------------------------------------------------------------------------
AP ID Name RfID Band Type ST CH/BW CE/ME STA CU WM
----------------------------------------------------------------------------------------------
0 2nd 0 2.4G bgn on 9/20M 17/30 1 8% normal
0 2nd 1 5G an11ac on 149/80M 23/31 0 2% normal
1 1st 0 2.4G bgn on 13/20M 17/30 3 4% normal
1 1st 1 5G an11ac on 149/80M 22/31 2 2% normal
5 3RD 0 2.4G bgn on 10/20M 14/30 2 8% normal
5 3RD 1 5G an11ac on 149/80M 25/31 1 2% normal
----------------------------------------------------------------------------------------------
Total: 6
Usage Scenario
After radio calibration has been enabled, an AP uses the Transmit Power Control (TPC) algorithm to calculate the transmition power to be adjusted based on detected neighbor information. If the transmition power calculated using the TPC algorithm is too low, radio coverage requirements may not be met.
You can run the calibrate min-tx-power command to set the minimum transmit power that can be adjusted through TPC.
Solution
1. Adjust channel values to prevent channel interference and move the channels far away from each other.
[AC6605-wlan-view] regulatory-domain-profile name default
[AC6605-wlan-regulate-domain-default] dca-channel 2.4g channel-set 1,6,11
2. Raise the minmum power value of AP as per below.
