Aggregate interference from White Space Devices into digital television systems

A methodology to calculate the maximum allowed power for White Space Devices (WSD) is defined in the recent regulatory statement produced by the United Kingdom Office of Communication (OFCOM). In deriving the methodology, it was considered that only one WSD radiates per pixel and that the aggregate interference will not be a problem in the short term. This article investigates the limits within which the summation of interference from WSD´s exceeds the regulatory threshold. The aggregate interfering power was calculated under the same conditions considered by the OFCOM regulation and assuming that the WSD geographical locations are modeled as a two-dimensional Poisson Point Process (PPP). Results indicate that aggregate interference due to multiple WSDs may not satisfy the interfering criterion used to protect the DTT system.