Wireless Access

Hello, in one of our residential halls our "G" radio is set to Min 3 EIRP and Max 9 EIRP.  We have received complaints about poor coverage for iPhone 4/4s users and users with G radio laptops.  I see all the access points are at the Min 3 EIRP even though we have the AP well spaced out.  The G radio coverage however appears to be lacking, however does "band steering" have any reason besides steering users to the 5Ghz to keep the G radio power levels at the min setting?  It just seems strange that there are no APs over 3.  AP models are 125 and we are at version 6.2.1.1.  Thanks in advance for any help.

If you do a show ap arm neighbors ap-name <apname> and will tell how close those APs can hear each other or show ap monitor ap-list

Why you have the min set to 3?

 If I do show ap arm neighbors ap-name ap-name, I do see a lot of aps, here is a cut and paste from the summary at bottom not sure if it helps:

Neighbor Summary: One hop 125 Two hop 128 Current Time: 2013-07-16 15:49:33

 

show ap arm rf-summary ip-addr 

Channel Summary
---------------
channel retry phy-err mac-err noise cov-idx(Total) intf_idx(Total)
------- ----- ------- ------- ----- -------------- ---------------
36 0 0 0 89 6/5(11) 0/7//29/11(47)
40 0 0 0 89 4/5(9) 21/4//34/64(123)
44 0 0 0 89 0/17(17) 11/20//158/35(224)
48 0 0 0 89 3/12(15) 30/4//70/54(158)
149 0 0 0 89 4/10(14) 32/0//93/26(151)
153 0 0 0 89 0/10(10) 0/25//79/43(147)
157 0 0 0 90 8/3(11) 42/3//35/26(106)
161 0 0 0 89 0/0(0) 10/14//0/12(36)
165 0 0 0 92 0/0(0) 0/3//0/0(3)
1 0 0 9 96 15/19(34) 93/17//452/80(642)
6 0 0 0 96 12/26(38) 88/32//469/152(741)
11 0 0 0 96 9/22(31) 53/15//463/80(611)

 

Actually it looks like there is co-channel interference based on the intf_idx column 

 

I upped it to 6 Min and 12 Max and will test.  Thanks.

My guess is you've got the APs in the corridors? Is that right?

 

If it is, it's likely the APs "hear" each other quite well, as they've line of sight to one another. As a result, they may well reduce power (with consequences concerning coverage into rooms, which would require obstacle penetration).

 

Upp'ing your min power is one approach. I'd recommend you do some sample baseline tests. I.e. go to one location, equal distance between APs, and move into a room off the corridor (to the furthest wall). Adjust the min power to suit, and repeat?

 

Of course, if that's not your AP layout this isn't good advice!!!

 

Thanks for your assistance it looks like ARM is working properly.  The aps are 125s and they are installed inside of a suite which then has about 4 rooms, farthest room is not getting very good signal.  When I increased power from 3-9 to 6-12 the closest ap stayed at 6 so if I am not mistaken increasing the min any higher will probably cause more co-channel interference and degrade performance. Looks like I will need to install an additional ap.  thanks again

If is not ARM is setting the power 3 it is likely that your AP can hear each other too much on g . Do you know how far part are those APs from each other ?

How are these APs deployed ? Wall mount or ceiling mount ?

What type of APs are you using ?

Yes that's correct increasing the power could potentially create more rf issues .

I think you should consider doing a site survey either physically or using the RFPlan software

Yes that is the plan site survey tomorrow. Thanks again.

That's great. Good luck

Also another AP may cause more issues too