I’m been getting a lot of interference in one or our towers where we keep 3 Cyclone 2.4 APs each with 120’ antennas. All APs are receiving sync via CMM.
What I have done to determine this is a self inflicting wound is to shut down all by one AP. I switched this single AP into an SM and ran the spectrum. The spectrum looks beautiful up until I fire the second AP, I see the upper channels blast all the way to -35dBm, and it gets even worst when I fire the 3rd AP on the tower.
I should mention that this is a new tower and we only have customers on the sector being used as a spectrum analyzer. There are no customers connected on the other 2 sectors.
For now we keep the radios off but I’m a little worried that this will become a big problem in the near future when we start serving subscriber on those two other sectors.
Any ideas?
Step 1: Read the manual. Hold on… let me say it again. Read the manual!
ok. Now for your particular question.
Verify that you sync input setting is correct on all 3 AP’s and that they are actually receiving sync properly.
Make sure Max Range, Downlink Data, and Control slots are the same on all three AP’s.
You also should make sure that your AP’s are not overlapping each other.
Three non-overlapping channels are recommended for use in a 2.4-GHz AP cluster: (All Frequencies in GHz) 2.4150 2.4350 2.4575
Chavex wrote: What I have done to determine this is a self inflicting wound is to shut down all by one AP. I switched this single AP into an SM and ran the spectrum. The spectrum looks beautiful up until I fire the second AP, I see the upper channels blast all the way to -35dBm, and it gets even worst when I fire the 3rd AP on the tower.
The spectrum analyzer will see all sources of RF, including those which would not be visible if it was to not listen during the period the AP would normally be transmitting.
Or, in other words, the behavior you are seeing is normal.
To truly check for self interference, one would need to run a link test to your customer and determine if the performace gets better or worse with the other AP's on or off.
Read the manual, and make sure all settings which matter for sync (distance, control slots, and ratio) are set the same on all AP's and you shouldn't have any self interference problems.
-forrest