Cognitive Radio – the First Model of Spectrum Sharing—Command and Control
The command and control approach dates back to the early days of RF usage in which exclusive rights were given to a certain usage in order to achieve acceptable quality of signal given inherent interference. While this may no longer be necessary, there are benefits to the command and control approach in that it provides a level of standardization that many technologies require to be successful. Also, some technologies that may not achieve profitability on their own can still be provided through exclusive frequency licensing, if deemed necessary for the society.
Numerous papers describe the challenges that the command and control system faces, the most common being the ever increasing demand for spectrum by new users and new uses. The military provides a case study of the use of a command and control frequency allocation system challenged by the demand for more use of finite spectrum. In addition, the technical, geographical, and operational factors increase the need for awareness of the spectrum and its usage.