Wireless and spectrum coordination
Where wireless belongs in a show system, what the room does to it, and why spectrum is coordinated across departments rather than per device.
What it is
Wireless on a show network covers several unrelated things that share a medium: Wi-Fi for control surfaces and monitoring, wireless DMX, tracking beacons and tags in whatever band the tracking system uses, and the mic and IEM plan being coordinated by audio. They interact whether or not anyone planned for them to. Design decisions include which bands carry what, antenna placement and orientation, how much of the system is allowed to depend on a wireless link at all, and whether 5 GHz DFS channels are acceptable given that a device on one may be required to vacate it if radar is detected. Spectrum conditions are venue-specific and change when the room fills.
Why it matters
A wireless link that behaves in an empty room at ten in the morning is not evidence of anything about the same room with an audience in it. Bodies attenuate, hundreds of phones raise the noise floor in the shared bands, and the failure appears at the worst possible time in the least reproducible way. Over a run the picture also drifts as neighboring tenants change their own installations. The practical consequences are a policy question as much as a technical one: what is allowed to be wireless, what must be wired, and what happens to the show if a wireless element drops for a few seconds. Deciding that in advance is cheaper than discovering it in performance.
Survey with the room loaded; a quiet-house measurement tells you very little about show conditions
A device on a DFS channel can be required to vacate it mid-show if radar is detected; decide if that is acceptable
Human bodies attenuate RF; antenna placement usually solves coverage better than raising transmit power
Coordinate control wireless with the mic and IEM plan, with one person holding both lists
Can tracking run over Wi-Fi?
It depends on the system and on which link you mean. Backhaul between sensors and the tracking server is normally wired, and should be. Some systems have wireless elements on the performer side by design, in which case the vendor sets the constraints. Putting a general-purpose Wi-Fi hop in the path of a position stream that automation or lighting depends on adds jitter and a failure mode you do not control.
How should we handle DFS channels?
Either avoid them for anything the show depends on, or accept and plan for the interruption. The requirement to vacate on radar detection is a regulatory behavior of the equipment, not a fault, so it cannot be configured away on compliant gear. Non-DFS channels are more crowded, which is a real cost, so this is a genuine trade rather than an obvious choice.
Who coordinates spectrum across departments?
One person, holding one list, covering mics, IEMs, comms, wireless DMX, tracking and Wi-Fi together. Departments coordinating separately produce plans that are each internally valid and collectively broken. The list should be a live document, since gear gets added during a run and an uncoordinated addition is the usual cause of an interference problem appearing weeks after opening.