“And it's the wild west out there at the moment.”
Diagnosing the problem is the easy part; finding a solution is much harder.
Some WiFi systems already actively manage how they use the spectrum, monitoring usage of bands and switching to the ones with less traffic.
“In the same way, you could do that with Bluetooth and other devices, but lots of other devices work on fixed bands,” says Professor Drake. “And while we must have this sort of adaptive monitoring and control, if that's an automated system, it can create unforeseen problems.
“The computer may decide, for example, to harness a particular frequency because it’s not being used, only to find out too late that it’s assigned to the fire alarm system, which only goes off once in two years or something. It means nobody's ever noticed the potential interference.
“So, it's a complex space.”
For now, Professor Drake and his team are analysing the spectra to build a 3D picture of the space to determine what – and the more challenging who – is occupying it.
“The ‘who’ can be hard,” he says.
“The ‘what’ is okay. I know that there are signals transmitted at these frequencies, and they look like radar, or they look like radio. But I need to do a lot more to find out who's transmitted something – what's called specific emitter identification.
“I'm just concerned with the physical nature of the electromagnetic waves and how they are transmitted. We're not dealing with the content, just making sure our signals get through to where they are supposed to go, without interference or misinformation.”