Toward dynamic real-time geo-location databases for TV white spaces

摘要

Recent FCC regulations on TV white spaces allow geo-location databases to be the sole source of spectrum information for white space devices. Geo-location databases protect TV band incumbents by keeping track of TV transmitters and their protected service areas, based on each transmitter location and transmission parameters using sophisticated propagation models. In this article, we show that keeping track of both TV transmitters and TV receivers (i.e., TV sets) can achieve significant improvement in the availability of white spaces. We first identify temporal and spatial wasted spectrum opportunities due to the current approach to white space detection. We then propose our DynaWhite architecture, which is responsible for orchestrating the detection and dissemination of highly dynamic, real-time, and fine-grained TV white space information, based on both TV transmitter and receiver information. DynaWhite proposes the development of a new generation of geo-location databases that combine conventional geo-location databases with novel unconventional sensing approaches based on the detection of passive TV receivers using standard cell phones. We present a quantitative evaluation of the potential gains, reaching 24 extra 6 MHz channels in some cases, in white space availability for potential deployments of DynaWhite. We finally identify research challenges associated with the adoption of our DynaWhite architecture.