A Proof-of-concept demonstrator for Cognitive Radio

The Adaptive Ad-hoc Free Band Wireless Communications (AAF) project is researching the possibility of using Software Defined Radio for wireless networks that needs to operate in an unknown or even hostile radio environment. Each node in the network needs to be cognitive of nearby transceivers in order to prevent radio frequency interference from and to other users and to survive jamming. So, in our system each node scans the radio spectrum to see which bands are free, so that these bands can be used for communication by the AAF network. The target application of our system is in a disaster relief wireless network. Since the chance of occurrence of a major emergency is very low, it will be very economical if the communication network of the rescue team can find free spectrum when it is needed, instead of reserving a fixed portion of the spectrum. In this paper we present a concept of a physical layer architecture of the scanning system of an AAF network node, and we will elaborate on the question of how it can be evaluated with of the shelf hardware. Keywords— Cognitive Radio, Software Defined Radio, Spectrum estimation