Which wireless, and why
Range, data rate, battery life. Every radio technology on a site is a different answer to that three-way trade, and none of them wins all three.
The whole landscape
One chart, eight radios
Put range on one axis and data rate on the other and the wireless world sorts itself out. Things at the top right need mains power. Things at the bottom left run for years on a coin cell. Nothing sits in the top-right corner on a battery, because physics does not allow it.
Click any of them for what it is actually for on a show.
The missing variable
Duty cycle is why a sensor lasts years and a radio mic lasts a show
A wireless microphone transmits continuously. A LoRa sensor transmits for a few hundred milliseconds and then sleeps for the rest of the hour. Both are radios, both have a battery, and the difference between a five-hour life and a five-year one is almost entirely how much of the time the transmitter is switched on.
That is what makes the range-rate-battery triangle escapable in one specific way: you can have range and battery if you give up being available. What you cannot have is range, rate and availability at once.
- LoRa is not a Wi-Fi replacement. It carries a few hundred bytes a few kilometres. Perfect for "is this generator still running", useless for anything streaming.
- UWB is a ruler, not a pipe. Its value is measuring time-of-flight precisely, which is why it does performer tracking rather than carrying audio.
- Wi-Fi is not a show-critical control path. It is unlicensed, contended, and shared with every phone in the building. Use it for convenience, not for cues.
- Bluetooth LE is a configuration channel. Excellent for setting a fixture up from a phone at the rig, not for running it.
Someone else's network
What actually changed between 2G and 5G
Each cellular generation is a different assumption about what the network is for. Worth knowing because a webcast uplink, a remote camera or an audience interaction all now ride on one — and because two of these generations are being switched off underneath equipment that still depends on them.
- 2G and 3G shutdowns strand equipment. Anything with an old cellular modem — remote monitoring, alarm diallers, some tracking hardware — stops working when the carrier turns that generation off. This has already happened in many countries.
- "5G" on a phone is often not standalone 5G. Non-standalone rides a 4G core, and the low-latency promises belong to the standalone version.
- Network slicing is the interesting part for us. A contracted slice with guaranteed behaviour is what makes cellular contribution viable for broadcast; ordinary consumer 5G is still a shared, best-effort network.
The one everyone underestimates
GNSS is a clock that happens to know where it is
GPS is one of several global navigation satellite systems — alongside Galileo, GLONASS, BeiDou and others, collectively GNSS. Each satellite carries an atomic clock and continuously broadcasts the time along with its own orbital position.
A receiver works out where it is by measuring how long each signal took to arrive. But it does not know its own clock error, so there are four unknowns — x, y, z and time — which is why you need four satellites rather than three. Solving for position necessarily solves for time as well.
That is the part worth knowing on a show. A GNSS receiver is an extremely accurate, free, traceable time source — which is why GNSS-disciplined grandmaster clocks are how large productions and broadcast plants get everyone onto the same PTP or timecode reference, and why a truck parked in an underground loading dock loses its clock discipline along with its sat-nav.
Legal frequencies by country are on the RF map, wireless DMX and mic hardware is under hardware, and how several signals share one band is on sharing the airwaves.
2 questions on the mechanism rather than the trivia. Nothing is scored and you can answer again — the explanation under a wrong answer is the point of it.
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1A LoRa sensor runs for years on a coin cell. A radio mic runs for a show on a much bigger battery. What is the main reason?
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Right. A sensor transmitting 300 ms an hour has its transmitter on for about 0.008% of its life. A radio mic sits at 100%. Almost everything else is a second-order effect next to that ratio.
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Its modulation does buy sensitivity, which buys range. It does not buy years of standby.
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They have far less energy than a mic pack. They last because almost nothing is drawn from them.
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Transmit power differs, but not by the factor of a thousand this life difference implies.
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2A production truck parks in an underground loading dock and its timecode starts drifting. Why?
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Cellular time is not what a broadcast plant disciplines its grandmaster from.
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It does, slightly, which is exactly why the oscillator needs disciplining from outside.
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Timecode inside the truck is cable-bound and unaffected by the building.
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Right. A GNSS receiver is an accurate traceable clock that happens to also know where it is. Lose the satellites and the grandmaster stops being disciplined and starts drifting on its own oscillator.
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Answers are kept in this browser on this device. Nothing is sent anywhere.
- LoRa or Wi-Fi or BLE?
- What changed from 4G to 5G?
- What is GPS really giving me?
Where to go next
These pages are a chain rather than a library — the next one along usually answers the question this one raised.
Everything on this page, in the index
Each of these has its own entry with sources, ports, gotchas and an open gap where a field is missing.