5 - Making decisions

Summary

Introduction

We now reach the ‘decide’ part of the ‘observe, decide and act’ cycle. In very simple terms the decision-making process is about selecting the actions the cognitive radio should take. Using the vocabulary introduced in Chapter 2, it is about choosing which ‘knobs’ to change and choosing what the new settings of those ‘knobs’ should be. Decision-making goes very much to the heart of a cognitive radio.

The decision-making process: part 1

In Table 3.2 a variety of cognitive radio applications and the main highlevel actions associated with them were presented. On examining the table we noted that many of the actions, whether commercial, public safety or military based, centre on two activities:

1. The cognitive radio shapes its transmission profile and configures any other relevant radio parameters to make best use of the resources it has been given or identified for itself, while at the same time not impinging on the resources of others.

2. If and when those resources change, it reshapes its transmission profile and reconfigures any other relevant operating parameters, and in doing so it redirects resources around the network.

A re-examination of Table 3.2 will confirm that these actions are standard throughout a whole variety of applications. It therefore comes as no surprise that two kinds of decisions that regularly need to be made are decisions that map to these two activities, namely decisions about how resources are distributed and decisions about how those resources are exactly used.