Cognitive RF - A Universal Framework for Communication Radar,
EW and Navigation

Instructors:
Vasu Chakravarthy, Braham Himed,
Air Force Research Laboratories, Sensors Directorate
Zhiqiang Wu,
Wright State University

Course Description:
Cognitive Radio (CR) has been proposed to address the spectrum congestion problem in communications. The spectrum congestion problem also affects other RF applications such as Radar, Navigation and Electronic Warfare (EW). Recently, the concept of cognitive radio has been adopted by different communities dealing with RF signals: CR and Dynamic Spectrum Access (DSA) in communications, cognitive Radar/DSA Radar for radar applications, cognitive GPS in Navigation and cognitive EW, to name a few. However, current research and development in these areas has been done separately, and functions of different RF applications reside on separated devices. To achieve the best spectrum efficiency, these research areas need to be integrated together to create a universal Cognitive RF platform. We will present our recent work and views on such a universal Cognitive RF platform and how to integrate spectrum sensing, RF signal detection/classification, RF signal parameter estimation, RF watermarking, frequency agile waveform generation technologies together to achieve an ultimate spectrum-efficient cognitive RF system. We will also present software defined radio implementations of some of the proposed technologies. Part of the SDR implementation was demonstrated at GLOBECOM 2010 and received the Best Demo Award. A shorter version of this tutorial was also presented at the Electronic Warfare Summit in 2010.

This tutorial is the first of its kind to provide a vision on cognitive RF as a universal framework to combine research and development in communication, radar, navigation and EW communities together. We believe we are at the stage where technology advances allow us to stop treating different RF applications individually and start a new era. The cognitive RF framework will provide capability to support multiple RF functions from one device or platform by generating waveforms that serve multiple purposes simultaneously, and create a truly dynamic spectrum access network. Additionally, this tutorial will include a software defined radio demonstration session that will give the audience hands-on experience of how to program SDR to implement some of the cognitive RF concepts in the tutorial.

Topics to be covered in this tutorial include:
 Universal cognitive RF framework
 Cognitive radar
 Spectrum sensing
 Adaptive waveform design
 Software defined radio implementation

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	Dr. Vasu D. Chakravarthy is a Senior Electronics Engineer at the Air Force Research Laboratories, Sensors Directorate, Electronic Warfare Techniques Development and Analysis Branch, and also serves as an adjunct faculty at Wright State University, Dayton OH. He received his B.S. in Electrical Engineering from the University of Illinois at Chicago in 1988, M.S. and Ph.D. in Electrical Engineering from Wright State University in 1998 and 2008 respectively.  Dr. Chakravarthy has been with AFRL since 1996 with an experience background in RF data links, Digital Receivers, Software GPS receivers and Communication Countermeasures. Research interest includes physical layer waveforms and signal processing algorithms related to Digital and Wireless Communications, issues related to Dynamic Spectrum Access, Cognitive Radio, Cognitive Jamming and Software Defined Radio technologies. Dr. Chakravarthy has written two book chapters, published over 40 papers in peer reviewed conference and journal proceeding. Dr. Chakravarthy is recipient of 2011 Association of Old Crows’ Clark Fiester Research and Development award for his contributions to Cognitive Electronic Warfare and 2011 AFRL Research and Development award for contributions to Dynamic Spectrum Access technologies addressing spectrum congestion problem.
	Dr. Braham Himed received his B.S. degree in electrical engineering from Ecole Nationale Polytechnique of Algiers in 1984, and his M.S. and Ph.D. degrees both in electrical engineering, from Syracuse University, Syracuse, NY, in 1987 and 1990, respectively. Dr. Himed is a Technical Advisor with the Air Force Research Laboratory, Sensors Directorate, RF Technology Branch, in Dayton OH, where he is involved with several aspects of airborne and spaceborne phased array radar systems. His research interests include detection, estimation, multichannel adaptive signal processing, time series analyses, array processing, space-time adaptive processing, and waveform diversity. Dr. Himed is the recipient of the 2001 IEEE region I award for his work on bistatic radar systems, algorithm development, and phenomenology. Dr. Himed is a fellow of the IEEE and a member of the AES Radar Systems Panel.
	Dr. Zhiqiang Wu received his B.S. from Beijing University of Posts and Telecommunications in 1993, M.S. from Peking University in 1996, and Ph.D. from Colorado State University in 2002, all in Electrical Engineering. He worked from 2003 to 2005 at West Virginia University Institute of Technology as an assistant professor. He joined Department of Electrical Engineering of Wright State University in 2005 where he serves as associate professor now. Dr. Wu co-authored one of the first books on multi-carrier transmission technologies for communications; he is also the major author of CDMA network management standard of China. Dr. Wu has published more than 70 referred papers in journals and conferences. He has received the Excellence in Research Award and Early Career Achievement Award of College of Engineering at Wright State University.