Cognitive Networks: Towards Self-Aware Networks

8.3. A Cognitive Ad Hoc Network

A cognitive network can be described as a network that is capable of knowing and understanding the context within which it finds itself and is capable of processing and acting on that knowledge as it sees fit. It could be said that cognitive networks also embody a sense of dynamic responsiveness as actions are typically taken in response to changing circumstances and changing (radio/node/network) resource availability. It is true also that cognitive networks embody a sense of fitness for purpose, as the the response of a cognitive network is typically focused on making best use of whatever limited (or abundant) resources are available for the (communication) purpose in hand. Looked at in this way, it is clear that similar philosophies underlie both ad hoc and cognitive networks.

The responsiveness in a cognitive network is, however, much more involved than in the case of ad hoc networks, as cognitive networks must be capable of learning and planning and to do so need a greater sense of self-awareness. It could be argued that a fully functioning cognitive network is the natural evolution endpoint of an ad hoc network.

8.3.1. The Cognitive Cycle

Since being introduced by Mitola ^[], the operation of cognitive radios has been frequently envisioned by the cognition cycle. The cognition cycle is a state machine that shows the stages in the cognitive process for a cognitive radio and a simplified version is shown in Figure 8.1. In simple terms, a radio ...