Discussion on:

Learn to do a wireless LAN site survey with this tutorial

The techniques discussed in ths article are useful for analyzing existing installations. However, for new installations this is of no value (with the exception of spectrum analysis). I would like to see an article that discusses techniques for planning AP placement BEFORE they are actually in place.

I have done a number wireless surveys using tools which will allow me to use one or more access points to determine real coverage and interferance levels. I find the tools that can over lay a building map are much more useful in planning a new wireless installation. When I do a survey I need to know interferance areas, other wireless devices and coverage distance. I also need to know of channels other devices are using. Really effective tools and techniques used properly remove any doubt as to how many and where to place access points.

This is a whole series of articles. This is just one part of it.

This was out last month and I think that's what you're looking for.
http://techrepublic.com.com/5100-1035-6061866.html

Let me know if that answers your question.

While you discuss AP coverage patterns and frequency allocation in that article, you do not discuss the practical aspects of performing a pre-installation site survey.

"Only a physical wireless survey can accurately predict coverage cells; we will go in to site surveying in next week's wireless article"

I mentioned that the patterns are circular in free space but are weakened by obstructions. There are software that predict coverage based on proposed AP location and a floor plan where you tell the software what the walls are made of and how thick. However they are very expensive or you have to pay a service to get it done and they still might not be accurate.

The best way to do a site survey is to physically test the APs by placing a couple in place at a time. You don't have to have all of them at one time but it helps, but you can do separate runs and you can consolidate the numbers later. My general rule is that if you simply assume that the Access Point has a safe coverage distance of 100 feet even through most walls, you can draw some circles and alternate them to avoid neighboring interference. That?s the best advice I can give you on this. You either pay for the software to predict coverage or you predict coverage with the ~100 feet radius rule and test your theories with a site survey. For a large project where you have to run the cables ahead of time before the walls are put in, your only option is to pay for the software or pay a service to do the prediction. You send them your floor plan with material descriptions and tell them where you would like the APs and they?ll map out the coverage for you.

That's the kind of information I'm talking about!

I'm faced with a situation where I will need to deploy wireless access at 7 - 12 manufacturing facilities. There will be any number of obstructions and walls that will need to be considered and to make matters worse, it's a dynamic environment.

My initial thought is to contract site surveys. However, I'm not of the mind to just issue an RFP and take the lowest bidder. I want to know the proposed methodology and tool set. However, I don't know what the correct methodology or tool set is!

This would be good material for an article or series of articles depending on how in depth you want to get. For example, until you just told me I was not aware that there was software that would allow you to passively design AP placement. And previously in this thread jnelson inferred that there are tools that allow you to take that one step further and map actual signal strength measurements over building plans. What planning software is available? What are the strengths/weaknesses of various packages? What are the costs? Who are some major players in this market? What should you expect to pay for this service?

Of course, the other option would be to do my own site survey. What training do I need? What tools?

I am not suggesting that you answer these questions in this thread. I'm not your editor, but I think that this would be good material for further articles. At least, I would read them!

It took only 2 hours total time, and I had performed the survey, ran the report (this took some doing), and used the data to map the signal strength on our existing facility map in Visio.

I am rolling out a new AP next week, and I clearly found the dead spots in our building.

Relating to the report... Excel kept hanging during the report process, so I edited the txt file in excel to remove all AP's which were not ours (about 40 other AP besides ours show up!)... Once the edit was complete, the report ran just fine.

Good Luck!

Chris

You need a really fast computer (my 3.45 GHz) to do it and it still takes some time to process. If not, you'll have to just let it run for a couple of minutes. If you filter out APs that are not yours, that won't give you an accurate picture of outside interference.

How to enable the macros in this macros excel tool so i can timestamp my live access point. Thanks a lots.

You need to Tools -> Options -> and the Security tab. There you will see a "Macro Security" button. You must set it to "medium" where Excel will prompt you allow or disallow macros.

As for your other problem of errors, try this first. What version of Excel are you using?

I'm using microsoft excel 2000. The location should be tools > macro > security. I've set the security level to medium, which it determines whether or not to run potentially unsafe macros. Anyway, it still shows "The macros in this project are disabled". Is this happen because of different version of Microsoft Excel?

I'm new trainee in my company and i'm interested in doing a site survey for the WLAN in our company which they replace the existing network to wireless network. Any suggestion for me to understand more about the relavant things?

Thanks for your reply.

It shows an error message when i try to click ctrl+shift+A. The message displays "Cannot run Visual Basic macro because of syntax error". Any method that can run the macro? Thanks again.

interesting. i think it would have been better if a free tool was used as an example, as this would have enabled one to follow along. airmagnet costs thousands.

I keep getting the error:

runtime error '1004'
Excell can not insert the sheets into the destination workbook because it contains fewer rows and columns than the source workbook.

Any Help?

I cannot download it.... all i get is a Duplicate entry '' for key 2 error when I try.

Things have changed quite a bit since this article was originally written. While this approach was pretty workable in 2006, easier solutions now exist. Check out WaveDeploy Basic, which is completely free and without a time limit, to map out signal strength, cochannel interference and TCP download speeds and place the results automatically on a map.

Paid versions of the program provide for advanced traffic types such as voice, video, QoS, assessments involving hundreds of clients, and report generation. However, the Basic version is sufficient for, well, the most basic tests!