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I was watching the CBT Nuggets CWNA Video on Antennas where the speaker shows examples of antenna modeling and suggest we visit this URL to download the antenna modelling freeware 4nec2:
http://www.si-list.org/swindex2.html

I downloaded the 4nec2 software & the 3D plugin, but the application is not intuitive at all. I would love to generate a 3D rendition of the coverage patterns made by the various antennas we use in our enterprise, (especially to use in presentations to the management) but I can't figure out how to do it.

Has anyone else seen/used/mastered this software?

The 3D examples on this page are very impressive, but the *read me* doesn't thoroughly explain how to get to the 3D point. If it did, I missed it.
http://www.si-list.org/NEC_Archives/4nec2_images.html

The antennas we use mostly are AIR-ANT5959 & AIR-ANT2012, and I am trying to determine which antenna is best suited to our hospital environment(s).

I am in the midst of an enterprise wide (>400 AP) migration to LWAPP (Cisco Unified Wireless Network), and I am at the stage where I may need to change the type of antennas that were installed originally.

This is my first post, but I have been lurking for quite a while. I look forward to the input of the CWNP community.

Hi Jennifer,

Usually we use predictive modeling software to find optimal placement of APs, to show co-channel and adjacent channel interference, to optimize overlap of channels, etc. Why exactly would you want to model an antenna? There are lots of software packages out there (AirWave, Aruba, Cisco, etc) that can do predictive modeling of a facility).

Hmmm....I checked with Cisco and CCIE (w) isn't a certification...

Devinator

The (w) stands for written. Cisco didn't offer any wireless exams at Networkers so I took the CCIE written exam. I figured I studied for it & passed it - its going in my signature. I'll start concentrating on getting ready for the lab when I've gotten a few wireless certs under my belt.

I wanted to "see" what the 3D coverage path of a particular Cisco antenna was. I use the WCS server to to predictive site surveys, and the heat maps that it generates, but I wanted to be able to visualize the coverage area that the antennas have in addition to the heat maps.

I know Cisco provides the Vert & Horiz coverage patterns in antenna white papers, but I have a hard time converting those line drawings into 3D images in my head.

Hi Jennifer,

I was being facetious - I've passed the CCIE R/S written as well...but it isn't a certification until you've passed the lab exam as well.

Adding "CCIE" to your resume, signature, or anything else violates Cisco policy on use of the name, gives Cisco grounds to yank your CCNP cert, usually ticks off engineers (that you may find yourself working with) that actually hold the CCIE certification, and IT Directors are rarely impressed with individuals that say they have a certification when they don't. At the level of a CCIE, integrity means as much as technical knowledge. Just my $0.02 - feel free to ignore it.

I see what you mean about the antenna coverage patterns. I'd consider taking a look at Motorola's Wireless Valley product to see if it gives you more of what you're looking for. I have some training videos that you can pull to take a look at it if you're interested.

Devinator

This is not the solution your modeling for the antenna dilemma, but may help you "see" the RF in a way that compliments the predictive.

Quite interesting discussion, regarding wanting to " see" the radio waves.

While I may not have an EE degree, nor fit in the category of the great wireless wizards out there, here is a pdf on indoor radio waves.

http://www.netsmithusa.com/pdf/INDOOR%20RADIO%20WLAN%20PERFORMANCE.pdf

Also for those that are interested: this is a good document on antenna design.

http://www.lairdtech.com/downloads/centurion-designguide-043002.pdf

And types of antennas to use:

http://www.radiolabs.com/Articles/wifi-antenna.html


I read too much! :)

Perhaps wanting to "see" the antenna signal is a bit overkill. I tried the modeling software again - and can't figure out how to model a manufactured antenna. It would make sense if one were making an antenna from X foot of coax cable, but not for a purchased manufacturer's antennas.

CBT Nuggets CWNA videos does give you a practical approach but does not cover some of the topics covered in the current CWNA exam (ver 3).

You should look for the following from alternate places like whitepapers, practice test and also the CWNA Official Study Guide as they are not much covered in the CBT Nuggets CWNA videos.

Power Over Ethernet (PoE)
Wireless Mesh (802.11s)
MIMO (802.11n)