An Urn Occupancy Approach for Cognitive Radio Networks in DTVB White Spaces

Abstract

Cognitive Radio paradigm has recently received considerable interest to address the so called 'spectrum scarcity' problem. In the USA, the Federal Communications Commission recently issued the regulatory for the use of cognitive radio in the TV white space spectrum. The primary objective is the design of cognitive devices able to combine the use of spectrum sensing, GEO-location and cognitive control channel to manage the network. The recent standard ECMA-392 defines physical layer and medium access control protocols to manage the network in a fully distributed fashion. In this work, we pursue the design of an efficient medium access control protocol for the cognitive control channel to flexibly and reliably exchange messages inside the cognitive radio network. Our main contributions are the following: 1) we propose a proprietary medium access control protocol based on the Standard ECMA-392; 2) we model the behavior of the cognitive radio network by means of a urn model approach and, 3) we investigate the ability of the cognitive devices to identify frequency holes (accounting for perfect and imperfect spectrum sensing) and in the end we study the network throughput.