Table of Contents
VLSI Design
Volume 2012, Article ID 716476, 13 pages
Review Article

Cognitive Radio RF: Overview and Challenges

1Institut Mines-Telecom, Telecom ParisTech, LTCI CNRS UMR 5141, 75634 Paris, France
2BL TV Front End, NXP, 14460 Colombelles, France
3Renesas Mobile Corporation, 35517 Cesson Sevigne Cedex, France

Received 4 November 2011; Revised 6 February 2012; Accepted 7 February 2012

Academic Editor: Christophe Moy

Copyright © 2012 Van Tam Nguyen et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.


Cognitive radio system (CRS) is a radio system which is aware of its operational and geographical environment, established policies, and its internal state. It is able to dynamically and autonomously adapt its operational parameters and protocols and to learn from its previous experience. Based on software-defined radio (SDR), CRS provides additional flexibility and offers improved efficiency to overall spectrum use. CRS is a disruptive technology targeting very high spectral efficiency. This paper presents an overview and challenges of CRS with focus on radio frequency (RF) section. We summarize the status of the related regulation and standardization activities which are very important for the success of any emerging technology. We point out some key research challenges, especially implementation challenges of cognitive radio (CR). A particular focus is on RF front-end, transceiver, and analog-to-digital and digital-to-analog interfaces which are still a key bottleneck in CRS development.