New Cisco 1552AP Mesh with 5508 controller version 7.0.116.0

Question

New to working with Wireless and the Cisco Meshing concept so have a few questions to ask.
I currently have the majority of the mesh setup and configured.  I have a setup with two RAPs with 9 MAPS connecting to each RAP.
First question is how many MAPS can connect to a RAP generally?
Secondly how can I block other cisco AP's that are not in my mesh network from trying to connect to my AP's
The below is constantly hammering the logs for 6 devices that are Cisco close to my mesh that are not mine.
8
Sat Nov 12 23:31:53 2011
Mesh child node '58:35:d9:aa:db:4f' has changed its parent to mesh node '88:f0:77:b7:c6:e0' from mesh node '88:f0:77:b7:c6:c0'.
Mesh Node '58:35:d9:aa:db:4f' failed to join controller, MAC address not in MAC filter list.
I have only added the MAC addresses of my AP's in to my AP Policy under security.  Would these other AP's affect the mesh in any way?
What I am seeing is the AP's constantly changing the child to parent relationship.  I have inherited this network and they have about 20 AP's all within a square mile which is absolutely overkill.  Would this close proximity of AP's together be the cause for the constant child parent changes?
How close should I have RAP's together.  The network was setup so two raps are about 20 metres apart and the AP's on one side connect to RAP1 and the other to RAP2?
How do you deal with Radar?  The install is pretty much next to an airfield with radar running and a few times I have seen all the AP's disconnect and change channels.
These are a few questions to start.  As I go through my logs I will continue to ask additional questions.  Cheers.

Answer 1

Out of order answers here.
Don't use the UNI-II band, this should help with the radar, for the most part.  Generally I only recommend 4-6 MAP to a RAP.  Othewise you can over saturate the backhaul, and of course the further out you go, the smaller the backhaul.
You could set a bridge-group name (BGN), for the RAP-MAP sectors.  This can help you limit the number of MAP to RAP, it also will help keep MAPs that aren't your off your network as they do look at the BGN.  However, this is not an end all method.  a MAP can still try to join a MESH using 'default' as it's BGN.
If the mac address isn't in your filter, the MAP won't be able to join, and the message it sends to try, is low bandwidth.
HTH,
Steve
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