We recently completed an installation with C9130E access points with AccelTex ATS-OP-2456-6-8PDART-ND-36 external antennas. These are similar to the Cisco ANT9103 with 8 elements, DART connectors, 2.4/5/6GHz, and 6 dBi, but there's no status light.
The AccelTex is seen by the AP as a DART adapter; it does not impersonate an ANT9103. The AP is enabling dual 5GHz radios along with the 2.4 GHz radio. 5 GHz slot 1 is using antenna A,B,C,D with E,F,G,H unchecked. 5 GHz slot 2 is using all available antennas, A,B,C,D. 2.4 GHz is also using all antennas available, A,B,C,D. (Screenshots below.) This is different behavior than our 9130Es with the ANT9103; the secondary 5 GHz radio cannot be enabled on those.
We have 8 of these 9130Es and external antennas in a lecture hall and 5 of them have an alarm for interference on both 5 GHz radios, the other two aren't alarming for interference on either 5 GHz radio. We are using 40 MHz channels and so far I left channel and Tx power to RRM. They seem to be making decent channel and power decisions, so I'm not sure why this interference is happening other than having tri-4x4 radios enabled on an 8-element antenna with all radios using antennas A-D. This is a large, rural university campus, so rogue APs aren't a concern.
Is this behavior with all three radios using antennas A-D incorrect? If so, how do I work around it? Do I disable 5 GHz slot 2 and change 5 GHz Slot 1 to use antennas E-H if I want one 2.4 GHz and one 5 GHz radio? What about dual 5 GHz with no 2.4 GHz, have one use A-D and the other E-H? Is any combination of radios sharing antennas acceptable? Is there any documentation on how to best utilize these 8-element antennas?
We are getting end user complaints about being disconnected, connecting but not passing traffic, or not being able to connect at all, regardless of .1x or open SSID. This is unique to this room, so I'm focusing this conversation on the AP antennas.
AccelTex says that they have customers using the dual 5 GHz with 2.4 GHz with success, which from what I'm seeing so far, I find hard to believe.
If it's relevant, we're using 8540 WLCs on 8.10.181.3.
Guarav - In this case, I think the lower power levels are OK since this is a high-density environment, the antennas are fairly close to the clients and to each other, and the smaller cell size encourages clients to associate to the AP closest to them for better client distribution. That said, it's not perfect, and some of the APs have more clients than others. I usually have to set power levels manually in large lecture halls like this. These 9130s have done a much better job choosing acceptable power levels than the 3800s, though. A signal check in the room this morning showed multiple radios within -65 dBm in any location.
In other news, I think I had a breakthrough. The APs weren't recognizing the antennas (screenshot below). I suspect the antenna may have been installed after the AP was booted (this is a brand-new building that just came online in the last several weeks). After rebooting the antenna, the AP recognizes the antenna, grays out the antenna gain option (which is correct), and I have the option to disable the dual 5 GHz radios.
Before reboot:
After reboot and disabling the dual 5 GHz (previously I simply set 5 GHz Slot 2 to Disabled status). Note all 8 antennas are selected by default. Which brings me back to one of my original questions, is it acceptable to have the 2.4 GHz radio using antennas A-D if 5 GHz is also using those antennas?
