PMP 100 SM TX Power Control?

Products PMP
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We are trying to do some spring cleaning on our network.  We have finally gotten our PMP100 units to update and now we wanna try to get them as stable as possible.  We have 100's of customers using our PMP100 network on 5.4Ghz.  This network was set up years ago before I was with our company.  Now that the software is up to date I'm taking the time to go through and look at some of the features that PMP100 has to offer us.  Some of these features seem to be new others seem to be things we just never used.  

We have AP's in our city pretty close together in order to cover our terrain (see image below for our tower layout).  We have problems all the time on certain towers with DFS detections.  I'm trying to get a better understanding on how the AP's detect DFS.  In a perfect world the AP gets a DFS detection and it changs to one of it's other preassigned frequencies and nobody notices the difference. In some of our areas when this happens it causes CPE's to go Idle.  Sometimes it happens this way. Ex. DFS on NE sector causes customer go to Idle on SE sector.  I figure this is due to the fact that the alternate frequencies are close together. Frequency planning is a nightmare with the amount of Ap's we have and having to have at least 2 feq on each AP.  It all just makes me dizzy to think about it.  

Doing some experiments in a small room it seems that a CPE close to an ap can cause an AP to get a DFS detection presumably caused by the CPE being fully powered and being so close.  Thinking of this applied in the field there maybe some of our customers close to the tower that could be giving us false DFS detections.

My question is under the Radio Tab their is a section for power control.  The AP has an option to auto set the power control of the attached SMs.  It even has a target receive level.  Would this help with alleviate our DFS detections.  Is this a must to be turned on?  Have we been foolish to not have it on all this time? Would turning this on cause any problems for us?

Do NOTE that the image below is labeled with ABC formate but our network is not setup that way.  I used this image on aother question regarding the ABC formate of 5.4GHz.  I figured why let a good diagram of our network go to waste. :)

-Mark

-St Joe Wireless

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About the DFS:- Dynamic Frequency Selection is the feature enabled on radios.Which helps them when they come into the contact of radar.But that's the theoritical fact. The real fact is how DFS works. When ever the radio sees any external energy on current channel it will consider that as radar.Hence you get the DFS detected message. Your findings were correct during the lab test.

Now this can be due to the SM at one perticular section is transmitting at high power.You can find that SM by taking down time from end customer and turning off each SM one by one or disconnecting from AP one at a time.And try to find which SM during the shut off time doesn't cause DFS to AP.That's one way to find.

Yes,enabling Automatic Transmitt Power Control can help you in this case. 

An AP can control registered SMs’ transmit power level such that a desired receive target power is
seen at the AP. This feature is useful in DFS regions so that signals from close-in SMs are not
being received at excessively high power levels which may cause the AP to false detect. It is also
useful for managing the general RF environment and controlling effective sector size by ensuring
that SMs don’t transmit at any higher power than required.

I hope this will help rectifying this disaster and false issue.

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