NCS antenna and RF prediction problem

Unanswered Question
Jul 17th, 2012


we bought a bunch of cisco 3600 series aps with external antennas

went to
followed the link 802.11n antennas
and choosed the right antenna for our purposes 5dbi omnidirectional 2.4Ghz only

the selection is AIR-ANT2506 3x AP

mounted the access points

connected to the wlc 5508

Then opened Ncs and created a new campus and a new map

positioned aps and...

result? the AIR-ANT2506 is not in the list so the only option is to chose "other"

and .... BAM

Ncs refuses to predict RF coverage cause the antenna is set to "other" and thus not compatible....


I have this problem too.
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Scott Fella Tue, 07/17/2012 - 05:11

Well, the problem is probably that they expect the 'N' APs to use a three lead antenna and not three separate antennas. I would just pick and antenna that is close in gain and use that.... Or the default dipole. NCS will or should still be able to perform calculations.

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Giuliano Gerardi Tue, 07/17/2012 - 06:44

thank you scott but... 

...the most close gain is 4Dbi (for 2.4Ghz on a DIRECTIONAL antenna, our is 5.2Dbi omnidirectional) however changing antenna on NCS maps means that the radio interface will be reset, gain set to that value and probably the operation of aps will be out of regulatory standards...

(EIRP [dBm] = Transmitter power [dBm] - cable loss [dB] + antenna gain [dBi] )

none of this is acceptable

Scott Fella Wed, 08/01/2012 - 16:57

You do have the latest NCS version running correct?

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Scott Fella Fri, 08/03/2012 - 10:48

I would ope a TAC case and see what they have to say.  I understand that if you choose others, NCS will not make any predictions, but TAC along with the BU can offer you some info for maybe future release.

Jacob Snyder Sun, 08/05/2012 - 12:36

Most likely TAC will tell you that your antenna is not supported in the 3600 since the AP requires dual band antennas and the 2506 is 2.4Ghz only.

I would suspect that the 2506 would be supported on a 3500 series access point in NCS since it does not use dual band RP-TNC. The use of that particular antenna with a 3600 seems very odd and possibly a poor choice for that AP. If that antenna is a requirement, RMA your 3600 and save some money and a headache with the 3500.

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kristjan.edvardsson Fri, 11/30/2012 - 07:42

I have a similar problem. I have 1262 in a warehouse with dual radio. 5ghz is 5140NV-R and 2,4Ghz is

2440NV-R. The 5Ghz antenna is listed in NCS but the 2,4 2440 is not. So what are my optoins, software upgrade or other antenna ? there is a warning with the other antenna saying that the heatmap will not work properly. Is there any documentation about which antennas the NCS versions support ?


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