Pasquale Cataldi
Using wireless networks to deliver superfast broadband to sparsely populated areas is becoming easier, cheaper and more reliable. This makes it an excellent way to achieve government-driven objectives for completing superfast broadband coverage.
TV white space (TVWS) is the wireless spectrum freed up by the digital TV switchover. It’s free to use, can cover several kilometres and passes through permanent obstacles such as trees and irregular terrain. This makes it perfect for spreading networks past the boundaries of existing of infrastructures, where covering long distances with cables or standard wireless technologies would be prohibitively expensive.
Nominet has been at the forefront of supplying tools that improve the reliability of TVWS, enabling ISPs to transform into commercial rollouts many of the pilot programmes run over the years across the globe.
What’s been happening recently and how has it improved the TVWS offering?
Improved regulatory framework
TVWS is now widely recognised as a technology that can be used commercially. Regulators in the US, UK and other countries now have regulatory frameworks in place that allow the use of the TV spectrum affordably. Costly spectrum auctions are not needed so ISPs only need to buy and install TVWS kit.
With major contributions from Nominet, among others, the regulatory environment was further clarified in December 2017 when the Dynamic Spectrum Alliance (DSA) issued new Model Rules and Regulations. Built on the groundwork laid by Ofcom and the FCC, and incorporating learning from in-field deployments around the world, the new rules harmonise the various pre-existing regulations and distil them in a set of best-practice technical rules for coexistence of users in the TV band. They also make it very easy for TVWS regulations to be put in place in countries that don’t yet have them.
Flexibility and low cost
Some installations use TVWS to deliver data from the end of the wired infrastructure to WiFi hotspots, which then share the signal around a local area. This works well in areas with small clusters of end-users, small villages for example, as the ubiquity and low cost of WiFi equipment makes it easier to spread the signal around.
Where consumers are more spread out, perhaps individual farms or houses, then it makes more sense to use TVWS point to point, installing TVWS equipment at each end-user’s premises.
In some countries, pilots have shown that white space devices have low power demands and can be powered by solar panels or wind turbines, depending on the climate. This means costs are kept low and installation quick and easy. ISPs can also use this as an environmentally-positive message in their marketing.
Faster, more reliable
From a technical standpoint, the upcoming new generation equipment delivers a faster and more reliable service. New radios with channel aggregation capabilities and MIMO antennas can now deliver connection speeds that are multiples of those observed until recently.
This puts TVWS technology in an excellent position to playing a part in providing superfast broadband to remote areas. The EU defines ‘superfast’ as higher than 24Mbps, while in the UK, Ofcom uses 30Mbps. The speeds achieved by these new radios are comparable to those thresholds, thus making TVWS a viable solution to deliver on broadband coverage targets set by governments and regulators.
Spectrum allocation – the problem
A key element in improving reliability and speed is to ensure that the subset of the spectrum that a WISP using TVWS is using does not interfere with other licensed services in the area. It is here that WaveDB is needed.
Providers deploying TVWS in a new location may not be the only people operating in that area. Different sub-sections of the TV spectrum have been allocated to other uses by different governments and regulators around the world. In addition, other ISPs may already be operating in a neighbouring or overlapping area. It is important conflict is avoided to prevent a slow or unreliable service for all.
Nominet WaveDB – the solution
Nominet’s WaveDB resolves all this. The first dynamic spectrum management (DSM) platform to be approved by the UK regulator, Ofcom, WaveDB assesses current use of the TV spectrum in a particular location and provides the list of channels and associated power limits so that TVWS services can be used without any risk of interference towards licensed users.
In day-to-day use on-site, WaveDB-enabled devices refer to geo-location databases containing all the information about current use of the spectrum. They can then dynamically select among the available channels the ones that allow them to have the best performance.
This means that regulators do not have to allocate the whole space in a region to one operator – different operators can share spaces without interference causing performance problems. In fact, regulators do not have to worry about coexistence between licensed services and the others, as WaveDB can efficiently and safely manage it, automatically.
Could you benefit from Nominet’s assistance?
Nominet help potential or existing TVWS network operators to assess whether the technology could work in areas where they operate. Services include:
- Use case evaluation
- Channel availability tools
- Radio planning tools
- Spectrum availability studies
- Link feasibility assessments
- Network deployment advisory services
- Policy advisory services
Why not get in touch to discuss spectrum sharing and how it could benefit you or your customers?
+44 (0)1865 332211