Antenna arrays have been known for a long time as important enablers of advanced wireless communication, offering, among other things, higher throughput and / or better performance for the same transmission power; better resilience to fading; better spatial resolution, etc. However, these benefits come at an increased cost in terms of the extra required hardware that involves a separate RF chain for each antenna; the larger device size required for hosting the antenna array; the higher circuit energy consumption due to the increased baseband processing, etc. In this talk we will review how an alternative technology, based on parasitic antenna arrays, that involves mixed analog / digital signal processing, can be used in order to provide the benefits of spatial processing, while using only a single RF chain, as well as smaller array dimensions. After presenting the main concept of this approach, we will present a number of representative techniques where parasitic antenna arrays can be used for transmit diversity, spatial multiplexing and spatial sensing. We will then show some designs / developed prototypes that target small devices such as mobile phones and wireless sensor nodes.
Dr. Constantinos B. Papadias is a Professor at AIT and a member of the Broadband Wireless and Sensor Networks research team. He is also AIT's PhD Program Academic Director. He was born in Athens, Greece, in 1969. He received the Diploma of Electrical Engineering from the National Technical University of Athens (NTUA) in 1991 and the Doctorate degree in Signal Processing (highest honors) from the Ecole Nationale Supérieure des Télécommunications (ENST), Paris, France, in 1995. From 1992 to 1995, he was Teaching and Research Assistant at the Mobile Communications Department, Eurécom, France. In 1995, he joined the Information Systems Laboratory, Stanford University, Stanford, CA, as Post-Doctoral Researcher, working in the Smart Antennas Research Group. In November 1997 he joined the Wireless Research Laboratory of Bell Labs, Lucent Technologies, Holmdel, NJ, as Member of Technical Staff and was later promoted to Technical Manager. From 2004 to 2005 he was an adjunct Associate Professor at Columbia University. In 2006 he joined Athens Information Technology (AIT) in Athens Greece, as an Associate Professor and was promoted to Professor in 2007. He is also currently an Adjunct Professor at Carnegie Mellon University’s Information Networking Institute (INI). He has participated in several European Commission research projects and is currently the Technical Manager of two FP7 Future & Emerging Technologies (FET) projects: “CROWN,” in the area of cognitive radio networks and “HIATUS,” in the area of interference alignment. He has served on the steering board of the Wireless World Research Forum (WWRF) from 2002-2006. He was a Member of the IEEE Signal Processing for Communications Technical Committee from 2002-2008, acting as its Industrial Liaison, and is currently an Associate Editor of the IEEE Transactions on Wireless Communications and the Journal of Communications and Networks. From 2007-2008 he was a National Representative of Greece in the European Commission’s FP7 program “IDEAS.” Dr. Papadias is a Senior Member of the IEEE and a member of the Technical Chamber of Greece.