WI-FI Optimisation Tool

[bmsadiq]

Hello Al,

I'm the new user, just registered today, since i need the help on the WI-FI application network.

We are planing to install the WI-FI Network, with indoor coverage for one our Client's and with outdoor coverage for another clients.

For indoor and outdoor coverage, we would be using CISCO AP. Let me explain you the both the scenario so that you'll could understand it clearly and help me out for my problem

Scenario 1 : Indoor Coverage

This is for the Stock Exchange area of almost 2000 sq.ft, and also it has 2 floor area, which is available with no of blocks of cabin for their employee, we have to provide with WI-FI, the no of customer who would be using is not more than 70- 100 no of users, since we could provde the WI-Fi for corporate users also, and the guest who would be coming for analzing the stock detail.

Since because of many obstruction I have to increased my no of AP's which is increasing my cost factor, at the first and second floor, there are many block and this is obstructing my AP coverage also it is reducing my coverage and for that i have to install another AP. This is all with using an integral antenna of AP's .

My question :
1. Does I used external antenna to increase my coverage and which antenna is best suitable for me to used.
2. No of non interfering and non overallapping channel in 2.4Ghz is only 3, i.e 1,6and 11, so does i have to used only there 3 channel what about other remaining channel, since i may installed almost 4 AP in ground floor(which is having main hall, caffe shop and visitors area), 3 on first floor and 3 on second floor.
3. Is there any testing tool and coverage tool applicable for WI-FI, through that i could do the detail testing and verify my network performance and my network signal quality .
4. How i could understand that my coverage is dropped because of the interference within the channel i have allcated to my network or is tht interference is an external.

Scenario 2 : Outdoor Coverage

There is one client who require the coverage for their outdoor coverage area, this is for their BAR CODE APPLICATION, there are many many no of OIL FULE TANKERS and TRAILERS located in that area and each trailers are provided with the bar code, the client want the complete coverage in that area, so that through that BAR CODE SCANNER TOOL, he could scan the trailors code, so to match in the database record for the securty purpose and for that whole area is to provide with the coverage.
Since as per the technical point of view, as the no of obstruction increase my coverage would decrease, so in that case what is the best solution i could adopt for this client, the area is almost 650 X 350 m. using Omni external antenna I could reach not more than 30 -40 % of that area, while using directional yagi antenna targetting all four direction I could cover almost 70-80%.The height of the antenna from which we had done the testing is almost 6-7 mtr from gorund.
My Question is
1. I need to cover almost whole area with no hot spot zone.
2. Best AP' vendors in market for Bar Code scanner users applucation.
3. Any other antenna avaible which provide me more gain.
4. Wha is the maximum signal required for this bar code application user.

You could send me on my office email ID of mohammad.babale@arabtel.net , all technical experts can share your very important comments.

With Best Regards //

[M/Q]

These are complicated projects and require more than guess work. I would strongly suggest making a best estimate on the coverage you are considering. Make a plan and layout a map of your ideas. Then get a node device and client device you intend to use and make a site survey. Locate the node where you think it will work and check out the coverage. Check out if there are any outside RF interferences. Also this will also show any dark spots you have. If you have coverage where you may see overlap of interfering channels then you need to get two nodes and locate them where you plan ans see what the overlapping will do to the client coverage. You really need to do the survey, it will answer all your questions. Each individual application has so many variables, that it is in your best interest to look good and make smart up front decisions. That way the amount of rework will be much less as well.

One other consideration is the outdoor location, I assume that the these are metal tankers. This might get very tricky as you will probably have to fight multipath interference from those tanks. It will be a random setting I suppose but making a similar site survey here before guessing what will work will again answer all your questions as well as bring any problems to the surface. After you determine the RF requirements, then we can help decide what devices and if they need external antennas.

Also in both cases you have to determine the average bandwidth per client. and make sure that there will be enough node bandwidth to cover that plus a safety margin if the sytems are to scale.

[bmsadiq]

First of all let me thank you for your immediate reply on my problem, I hope that your feedback has boost me to be in touch in this WI-F planet forum and websites.

I have done the complete survey for both the scenario, with the first scenario where we need to install the Access point for the indoor coverage , could not be done since there is an existing network working in that location and the client could not shut down those network, and want us to do the tesintg without disturbing the eixting network.

Since we are also operating under the same licence band, in that case we would definetly face the interference problem and none of the system will work .
Any option from your point of view, also i have ask the planning tool if any available in the market, please let me know and what that planning tool will help me out also any testing tool which is cost effective and would be able to do the test regarding the performance and coverage point of view.

For scenario no 2, we did the testing using directional YAGI Antenna with in outdoor area, and we did find the changes compare to the integrated dipole antenna of CISCO AP , but there is still not 100% coverage, we have done the testing at the height of 6-7mtrs , and found almost 70-80% coverage, if you increased the height, will it ncrease the coverage, also we have testing within all the metal tanks where the BAR CODE on the tankers were available, and we found the coverage even after multipath reflecting loss. What i am tryng is to provide alteast four AP with directional external antenna, facing at all four corners of the the client area, so that i could cover all those area.

What i'm worried is how could i definetely sure about my coverage to the client and what is the minimun probabilty i could show to my client regarding the coverage point of view, is 20% or 15% is enough for his BAR CODE application requirement.Since at many part I am getting the coverage but with very low signal of only 15- 20% singal.

regards //

[M/Q]

In the first network, does your have to co-exist with the other network? If so, how many channels are they using? You may be in trouble with interference. And have to resort to 11a to stay from interfering with each other. I would do a survey of their network as is and see where it's boundaries are, and how it will interfere with your project. It has to be figured out before any purchasing.

If you are talking about devices that will help you read and do site surveys, there are several devices, AirMagnet, YellowJacket, and AiroPeek are a few very good ones. If you are talking about a software program that will help map out the situation, I believe Airmagnet helps with that as well. You will have to check out their respective websites. Or PM keenanj about Airmagnet.

In the second scenario, the antenna height increase may help or it may hurt, it depends on the vertical coverage angle. If you raise it too high, you may miss the clients near the antenna as the signal is above them. I would be worried about 15-20% too. That is not enough to get a good link and it will be even worse with the multipath interference. How are you determining the percentage? If it is using the client configuration utility, I would not want to see less than 80-90% as they are not a very good indicator, and I have seen clients with 100% actually have a very weak signal.

[spiderbite]

This is a lot of requirements to consider. If there is any chance of paying for

professional service I would highly recommend it.

Inside-

If not, Then the very first thing I would do is determine the amount of Bandwidth

you will require by using a network analyser, Sniffer or some such device.

Once you have arrived at a number I would suggest that you increase this number

by half, just for good measure or even more if you plan on operating other

equipment over the system such as IP Phones etc...

Take this number and multiply by the number of users you could possibly have and

this will give you the total amount of required throughput you would need if

everyone were on the network at once.

Normally, this is where I would discuss oversubscription, but in a stock exchange

enviroment, I will assume a lot of streaming data, that would be old before it

ever got a chance to be retried over and over again.

Point is you need to make sure you have Adequate Bandwidth for all users and

applications.

Since each AP is going to yield a widely respected 5.5Mbps, you should then

divide 5.5Mbps into your total bandwidth requirements and this will give you a

very good idea of how many AP's you will require.

Now you have to decide about how many users you wish to share bandwidth under one

AP. Taking into consideration the impenetrabilty of your concrete building, this

could take some doing.


Please remember that coverage is not throughput! This is vital..


Not knowing how your facility is laid out, the walls may make a lot of this

decision for you.

Also 100+ people in 2000 square feet of space,along with furniture etc...is alot

of attenuation caused by water filled bodies. This needs to be incorporated in

your plan.

Having said that, I would make sure my Cisco 1200's were IOS firmware, and I

would be inclined to use some type of diversity omni or patch antenna. This will

help a great deal with any multipath issues you might face. The survey tool that

comes with the Cisco client software would do very well surveying this facility.

Smaller cells, lower power= better design and load balancing. Also consider about

a 40-50% overlap between cells. Your survey will answer these questions.

Be creative, the only rule is it has to meet all your requirements and work

correctly the first time.

By the way, what is the existing system for and could you incorporate both

systems and migrate them into one robust infrastructure?


Outdoor-

The metal tankers would pose a problem from a 4 corner approach. You would have

to cross paralell lines across the tankers. Is there any light poles in the lot

themselves you may be able to utilize for antenna placement? If you must use the

building around the lot you should try to aim down the rows of trucks if they are

parked in straight lines.

Without more info on this aspect I would not even venture a guess.


Many solutions could be used out here depending on the layout and setup.


Everything else you asked about is beyond my scope.

I must admit, I envy your task. To sucessfully pull this project together would

be a very cool thing indeed.


Best regards,

Spiderbite