Cognitive Networks: Towards Self-Aware Networks

10.1. Introduction

The term cognitive radio refers to a number of technological and research trends, some of which appear to bear little relationship to one another, other than being plausibly associated with 'making wireless devices more intelligent.' Before embarking, therefore, on the main theme of this chapter, i.e., the role of formal semantics-based technologies in cognitive radio, it is important to offer a reasoned point of view concerning the intended meaning and scope of this term.

Radio as a form of communication has always involved more than physical phenomena: without explicitly or implicitly agreed upon conventions or protocols, wireless communication is either inefficient or, in the worst case, impossible. From this point of view radio consists of three essential elements: devices, a 'medium' (electromagnetic energy transmitted and/or received through the spectrum), and coordinated systems of conventions. The term 'cognitive,' when used to modify 'radio,' applies to both devices and the systems of conventions governing their use in relation to the medium. Cognitive radio is a type of technology that exists within wireless devices and makes them behave in ways that can be said to be intelligent. It is also a way of architecting the systems and conventions surrounding human use of the radio spectrum so as to make it possible for such radio devices to coexist with themselves and other devices. We use the expression cognitive radio device architecture to refer to the ...