What exactly is... cognitive radio

Abstract

The latest thing after software defined radio (SDR) is the cognitive radio. The idea for cognitive radio has risen from the need to utilise the radio spectrum more efficiently, and to be able to maintain the most effective form of communication for the prevailing conditions. By using intelligence built into a radio, it will be possible to look at the spectrum, detect which frequencies are clear, and then implement the best form of communication for the prevailing conditions. In this way cognitive radio is able to select the frequency band, the type of modulation, and power levels most suited to the conditions and the application. Although the basic idea for cognitive radio is fairly straightforward, the practical implementation poses many problems. As a result, work is progressing to investigate the best methods of achieving a workable system.