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The RF environment at stadiums

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e100:
Is wireless communication (ISM bands) viable in stadium type environments where there are perhaps 50,000 mobile phones, (some out of spec) filling the RF spectrum.
How do you simulate this type of environment in the lab? Is there a 'stadium in a box' jammer device that simulates this type of RF environment?

Benta:
Which ISM band? 305, 433, 868, 905, 2.4G?

mick_lee:
Wow, that's a really expansive question, and one that cannot be answered with a couple of quick lines. 
The reason it's not easy to answer is there are many factors that feed into how equipment works in a noisy or congested signal environment.
The most fundamental, I suppose, is the Shannon Hartley channel capacity theorem - which places a fundamental limit on the amount of data that can be transmitted for a given bandwidth for a given signal to noise ratio.  https://en.wikipedia.org/wiki/Shannon%E2%80%93Hartley_theorem
That's just the physical layer - on top of this we have the rest of the OSI 7 layer stack https://en.wikipedia.org/wiki/OSI_model- which will also play a big role in interoperability.
Modern devices use adaptive modulation schemes such as COFDM - which adapt to use available spectrum.  New to the market are systems that use electronically steerable antennas (MIMO) to allow what is referred to as 'spatial diversity'.
So I'm sorry I can't give you a quick and simple answer :-// - because there is one really!

tggzzz:
The OP's question is too vague to be answered. If he bothered to say the purpose of the simulation, then it might be worth considering answering.

He should also do some basic research on commercial equipment that is designed to be used in concerts halls, theatres etc. That should give some hints.

As for having many cellphones, one of the more interesting specfications for a cellular system's capacity is "bits/s / Hz / m2". The "bits/s / Hz" is how close a call gets to Shannon's limit. The "/ m2" is how closely together you can squeeze the cells.

e100:
I shall rephrase the question.

Does anyone have any practical experience of trying to use an ISM band (any ISM band) in a stadium environment?
Was it a complete failure or did it sort of work?

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