Since its launch in 2005, our Digital Dividend Review (DDR) has considered how to make the spectrum freed up by digital switchover (DSO) available for new uses. This includes the capacity available within the spectrum that will be retained to carry the six digital terrestrial television (DTT) multiplexes after DSO. This is known as interleaved spectrum because not all this spectrum in any particular location will be used for DTT and so is available for other services on a shared (or interleaved) basis.
In our statement of 13 December 2007 on our approach to awarding the digital dividend, we considered the use of interleaved spectrum by licence-exempt applications (i.e. those exempted from the need to be licensed under the Wireless Telegraphy Act 2006). We concluded that we should allow cognitive access as long as we were satisfied that it would not cause harmful interference to licensed uses, including DTT and programme-making and special events (PMSE). This could potentially bring substantial benefits to citizens and consumers in the form of new devices and services.
Cognitive devices should detect spectrum that is otherwise unused and transmit without causing harmful interference. They have the potential to support a wide range of uses, including high-speed always-on broadband.
In a consultation published on 16 February 2009, we proposed a number of technical parameters that we suggested would prevent harmful interference while enabling licence-exempt cognitive use of interleaved spectrum. This statement concludes on some of the issues raised but notes that further work is needed on others.