If your looking for a regularly available test
environment..Try a large church. Especially one with a cell site next door.
I run spectrum management for my church.
150-300 phones looking for WiFi at a time pushed us to 5.6 Ghz for show control. My SA is a regular visitor. We "bait" the phones with 2.4 Ghz nodes and then use 5.6 and some really oddball wireless mic frequencies.
Our sound mixing console is an X-32 Rack and mixing is done on touch screens on Ipads, this allows the sound guys sit with their families. The X-32 has its own access point, set to private.
One of the keys is not using default frequencies on the nodes.
Our eight wireless mic receivers have ethernet
for adaptive allocation of channels. They also scan the spectrum and display it on a PC.
Intermod and mixing products from the cell tower makes life interesting. I use WA5VJB log periodics to "look under" the towers pattern and diversity receive setups.
if you are a tour or theatre in the US, you have options for licensed channels, if you need 60 or more frequencies.
About four times a year, or whenever the church secretary notes a a truck at the cell site, I will check for interference on the SA.
Generally if node powers are kept to the minimum needed, channel reuse works fairly well at 2.4 Ghz with ODFM etc.
I am utterly amazed how often the cell site hardware gets updated. They also have adaptive down-tilt on the antenna arrays.
not too long ago, reforming and selling the TV spectrum resulted in many low power entertainment channels going away. Losing that frequency space to cellular cost my church 750$ per channel to re-equip. We're told we could have 240 mics in the digital system at once. In 30 Mhz of Spectrum.
In our case, we found the automatic frequency selection system in the mic receivers often chose to operate right at the tail end of an active ATSC Digital TV channel with no noticeable interference. Of course, I will manually move them off the TV channel.
Covid forced us to come up with a zero budget camera array for live streaming. Ipods/Ipads on 5.6 Ghz saved the day. We've found our limit on emitters to be quite high in a 60x100 for space. Ten in our case.
This change by the FCC resulted in many studies and new protocols for the entertainment industry.So recent data is out there if you look.
Fortunately for us, we had a wealthy donor. We would have
rather spent the money on charitable causes.
At a concert, immense work will be done in spectral planning. For something like the Olympics, it starts years in advance, and typically the National Authority makes draconian rules for the region around the event, and re-allocates spectrum on a temporary basis.
915 Mhz is often considered useless in the Midwest US, every household with natural gas has a gas meter. Every gas meter is chirping loudly in the 915 band multiple times per minute with billing information.
Yes, there are simulators, for cellular and WIFI, but not so much for ISM. Most nations severely limit the ISM duty cycle.
try Rhode and Schwartz, and Candela Technologies for simulators.
My cheap Siglent SA has an option for measuring spectral occupancy and adjacent channel interference etc. So do most other brands.
My friends in the entertainment industry use WIFI all the time. So does a friend who does RF Engineering for Disney parks. Most of them do not care about the tiny details. They all tend to have hardwired backups using specialized ethernet protocols such as ArtNet or OSC or Dante. I would find a touring consultant or talk to a hardware manufacturer.
Remember, good WIFI hardware in that environment is going to be constantly adaptive and monitor spectral occupancy. But, no two stadiums or theatres will ever be standardized.
⁸
Steve
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