How to build a national cellular wireless network for £50m
It's easy when all your customers are machines
A team of 20 developers in Cambridge wants to build a new radio network covering the entire country, but plans to cut costs by only offering connectivity to silicon-based customers.
The team has set up a company called Neul with plans to make use of unused TV frequencies ("white spaces"), and is busy designing base stations for national deployment.
The idea is to connect up all the electricity meters, cars, e-readers and suchlike over a new national network that the team reckons can be built for around the same amount that O2 spends on its network every couple of weeks.
White Space kit uses the same frequencies as terrestrial digital television, branded Freeview in the UK, but only in locations where they aren't being used to send TV pictures. Freeview can only reuse frequencies with huge geographic separations, so a band filled with TV in London can't be reused in Oxford, but a low-power transmitter in Oxford can use that same frequency for a different application without bothering the Londoners.
Professional wireless microphones have been doing that for decades (in the analogue TV bands before DTV) which is why the PMSE (Programme Making & Special Events) crowd are so upset about exploitation of white space.
But despite complaints from Dolly Parton and the Church of England, regulators around the world are set on making use of it, with most following the US model of unlicensed devices coordinated through online databases of available frequencies.
How those databases are to coordinate with each other is still under discussion in the US, and the UK hasn’t yet decided who will run such a thing. But Neul's CTO William Webb wrote the book on radio spectrum management (quite literally) and is confident that Ofcom will sort it all out in the next year or two which fits the company's schedule well.
White Space is often presented as being like Wi-Fi, only better, but that's a result of clever marketing by proponents rather than any technical or applicable similarity. White space refers to a series of geographically-restricted radio frequencies rather than any technical standard that requires interoperability; white space bands may be used by everything from TV remotes to broadband internet access, without any potential for them to be compatible.
Broadband internet is the poster child for white space applications, since it only requires two compatible devices (one at each end), but if standard technologies can be adopted then the frequencies have a much greater potential.
Neul is well aware of that, and plans to set up a Special Interest Group (SIG) later this year with a view to defining those standards.
The idea is for a client device, embedded in a car, e-reader or washing machine, to listen on various predefined slots within the white space frequency range. The device will only transmit in response to a poll from a fixed base station, that station then uses the online databases to be sure there aren't any local TV transmissions to interfere with.