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I'm looking for an idea of what qualities to look for in the equipment for a wireless network that covers the entire area of an outdoor arena. The area is rectangular-ish in shape. 400ft wide and 600ft long. It has 6 light towers, 1 on each of the 400 foot ends and 2 on each of the 600 foot ends. I can mount on anything and spend as much money as needed.

The needs of the network would be to provide access for, up to 15 wireless HD cameras with audio, and a public-wifi network. Can someone point me in the right direction as far as figuring out what information is critical for setting up a wireless network with many users having different needs in a small space?

Jeff Ferland
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jeeshofone
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    I hope you've got a good budget. To do this, you're looking at about 50-100k USD in hardware alone, before you talk about consultant fees or backhaul. – Tom O'Connor Apr 15 '12 at 22:25
  • Sounds fine to me. Mostly I just want pointed in the right direction with the hardware. This project is very funded. – jeeshofone Apr 15 '12 at 23:08
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    How many concurrent clients are you targeting, not counting the HD cameras? I would start with this Cisco data sheet on [stadium WiFi applications](http://www.cisco.com/web/strategy/docs/sports/c78-675063_dSheet.pdf). – David Schwartz Apr 15 '12 at 23:38
  • Wow that is a very helpful sheet! The arena seats no more than 5 thousand. The HD video streams are a priority. If it is not ideal to have the public wifi on the same hardware as the video, the arena doesn't need to have it. However, If it is possible they thought it would be nice. I would say maximum concurrent clients would be around 10% of the attendance maximum, so ~500. – jeeshofone Apr 15 '12 at 23:49

2 Answers2

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Make sure your private network equipment is on 802.11a/n (5Ghz band). That provides more channels and less native interference, so you'll find more reliability.

Work with directional antennas and reduce access point transmission power. The directional antennas will reduce noise from other areas. The more isolated cells you can get, the more clients you can handle.

If you can make sure that your power is such that your APs aren't stomping all over each other and that your APs don't listen to areas they can't respond to (a stronger signal from an undesired area), then the last catch will be the omnidirectional user devices... and those will just have to play nice or figure it out.

While traditional wisdom is to use fully non-overlapping channels, do remember that some overlap may be a beneficial sacrifice for being able to get more adjacent cells. The Wifi spec demands that the further you get away from the center channel, the lower the signal strength becomes. Thus, while channels 1 and 6 dont overlap at all, adding an AP using the space of 3 or 4 will do less harm than using 2 or 5 and in a high-interference environment may work to increase overall bandwidth.

Generally, there's benefit in more expensive controllers and also in controllers that run multiple radios from a single unit. When laying out your network, you'll get a big boost in positioning things if you can turn on just a few radios at a time and map their coverage, then test with everything online at once.

Since you've got a hefty budget, consider hiring a consultant who has previously worked on conference wireless deployments. This is one of those areas where most of the work needs to be done beforehand and can't be really be fixed during an event if it wasn't right the first time.

Jeff Ferland
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    +1 for putting private network equipment on 5 GHz -- but note that, these days, that can be 5GHz 802.11n as well as 802.11a – Skyhawk Apr 15 '12 at 23:54
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    +1 to this answer and the comment. Remember the basic idea -- directional plus low power enables multiple cells at the same frequency. The basic idea is to use high gain, directional antennas aimed at a "cluster" of seats with adjoining clusters using different frequencies. Even though the users won't have directional antennas, other antennas for the same frequency won't pick up their signal because *they* are directional. – David Schwartz Apr 15 '12 at 23:59
  • ... and +1 to both those comments. Good additions / clarifications! – Jeff Ferland Apr 16 '12 at 00:03
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In addition to what Jeff said: Be aware of foliage. If you do a site survey in the winter, do one again in the spring/summer. If you have a lot of trees in the area, you will have increased interference when they are full of leaves! If this is a problem for you, you can counteract this by placing the APs lower to the ground below the treeline and using direction antennae. This usually means more APs but it's better than having garbage reception for 6 months out of the year.

Also, don't just plan for coverage, plan for capacity. Many high-end APs are only spec'd for a max of 100 users with a recommendation for no more than 50. Try and plan for coverage as well as capacity.


Edit: I misread your question, I thought it was about a large outdoor area that the arena was part of. You probably don't have to worry about trees, but I'll leave this here for future visitors that may have to deal with them.

MDMarra
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