11:00 - 11:30, A54 PSC
Statistical Modelling of TV interference for shared-spectrum devices
Radio spectrum is a much sought-after finite resource. Digital radio devices can, however, tolerate some interference without detrimentally affecting the quality of reception. This allows for the possibility of spectrum sharing. Ofcom is currently developing a regulatory scheme for the unlicensed use of TV whitespaces (TVWS) by whitespace devices (WSDs). The TV spectrum has favorable propagation properties which could allow for novel applications. For example, TV whitespaces could be used for the provision of broadband in remote rural locations where it would be expensive or impractical to develop a wired or optic fibre infrastructure. The Ofcom scheme makes use of repeated probabilistic approximations, which will affect the accuracy of these calculations. The accuracy of the calculations is important, as too low permitted powers will restrict the number of potential applications of WSDs, whereas too high powers could affect television reception.
In this talk we give a brief overview of the Ofcom calculations and its associated problems, before showing how the problem can be transformed into a problem of finding a quantile of a sum of lognormal random variables. This allows for the possibility of accurately calculating permitted powers through simulation.