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Home | Seminars and Symposia | Past seminars/symposia: Friday, November 9, 2012

DTC Seminar Series

Array Processing in The Face of Nonidealities


Visa Koivunen
Signal Processing
Aalto University

Friday, November 9, 2012
3:00 p.m. reception
3:30 p.m. seminar

401/402 Walter Library

KoivunenIn this talk we describe techniques that allow the practitioner to apply high performance array processing algorithms using real-world sensor arrays with nonidealities. Arbitrary array geometries and processing data in azimuth, elevation and polarimetric domains are considered. We acquire a realistic array steering vector model by taking into account array nonidealities such as mutual coupling, mounting platform reflections, cross-polarization effects, errors in element positions as well as individual directional beampatterns. This facilitates achieving optimal or close-to-optimal performance and retaining high-resolution capability despite the nonidealities. Moreover, tighter performance bounds may be established for parameter estimation. We describe how the various approaches can be applied in practice in the context of high-resolution direction finding as well as beamforming so that problems related to beamsteering, SOI and interference cancellation are mitigated.


Visa Koivunen (IEEE Fellow) received the D.Sc. (EE) degree (with honors) from the Department of Electrical Engineering, University of Oulu, Finland. From 1992 to 1995, he was a visiting researcher at the University of Pennsylvania, Philadelphia. Since 1999, he has been a Professor of Signal Processing at Aalto University (formerly known as Helsinki Univ of Technology), Finland. Since 2009 he has been Academy professor at Aalto University. He is one of the Principal Investigators in the SMARAD (Smart Radios and Wireless Systems) Center of Excellence nominated by the Academy of Finland. During his sabbatical leave in 2006-2007, he was a Visiting Fellow at Nokia Research Center, as well as Princeton University. He makes frequent research visits to Princeton University. He has served as Nokia Visiting Fellow in a part-time basis. His research interests include statistical, communications, and sensor array signal processing. He has published more than 350 papers in international scientific conferences and journals. He co-authored the papers receiving the IEEE Signal Processing Society Best Paper Award for 2007 (co-authored with J. Eriksson). He is a member of the editorial board for the IEEE Signal Processing Magazine. He is also a member of the IEEE Sensor Array Multichannel Signal Processing Technical Committee. He is also serving in the industrial relations board of the IEEE SP society.