A cognitive radio realization based on a Petri net approach

Reconflgurability of transceivers for wireless communication systems such as GSM, UMTS, WiMAX and WLAN will become increasingly important. Therefore, a flexible and reliable software and hardware architecture based on the software-defined radio (SDR) paradigm is a meaningful concept. SDRs have paved the way towards cognitive radios (CR), which are based on SDRs that additionally sense their environments, track changes, and react upon their findings. A CR is an autonomous unit in a communications environment that frequently exchanges information with the networks it is able to access as well as with other CRs. A tool is required for the description and design of the multitude of concurrent processing tasks running on the CR. Petri nets are both a simple and strong solution and are recommendable to deploy them for these demands. In this manuscript, the authors present a concept for a CR as well as the hardware demonstrator realization. This demonstrator was developed by the authors and makes use of a digital signal processor (DSP) in combination with field-programmable gate arrays (FPGAs). The authors will describe the solution also in view of the recent developments of IEEE 802.22.