Olav Tirkkonen is associate professor in Communication theory at the Department of Communications and Networking in Aalto University, Finland, since November 2012. He received his M.Sc. and Ph.D. degrees in physics from Helsinki University of Technology in 1990 and 1994, respectively. Between 1994 and 1999 he held post-doctoral positions at the University of British Columbia, Vancouver, Canada, and the Nordic Institute for Theoretical Physics, Copenhagen, Denmark. From 1999 to 2010 he was with Nokia Research Center (NRC), Helsinki, Finland, most recently acting as Research Fellow. At NRC he first concentrated on physical layer resarch on multiantenna communication. In 2004-2006 he was leading the Nokia-wide research for the physical layer standardization of UTRA Long Term Evolution. In 2006-2012 he was professor in telecommunications at Helsinki University of Technology. As of fall 2012, he has published some 130 papers, is the coinventor of some 70 families of patents and patent applications and coauthor of the book "Multiantenna transceiver techniques for 3G and beyond". His current research interests are in multiantenna techniques, cognitive cellular systems, and self-organization of wireless networks.