EE Systems Seminar

Abstract:
In this talk we describe techniques that facilitate applying high performance array processing algorithms using real-world sensor arrays with nonidealities. The theoretical background is in wavefield modeling that allows one to develop computationally-efficient and asymptotically-optimal array processing methods regardless of the array geometry (conformal arrays). Wavefield modeling also facilitates incorporating array nonidealities into array processing methods and performance bounds. Parameter estimation and beamforming in the azimuth-elevation-polarimetric domain will be addressed. 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. This is joint work with Dr. Mario Costa.


BIOGRAPHY:
Visa Koivunen received his Ph.D in electrical engineering from the University of Oulu, Finland. He was visiting researcher at the Univ of Pennsylvania in 1992-1995. Since 1999 he has been full professor of signal processing at Aalto University (Helsinki Univ of Technology), Finland where he currently holds the Academy Professor position. He has been an adjunct professor at Penn and visiting fellow at Nokia Research Center. He has spent multiple research visits and sabbaticals terms at Princeton University. His research interests include statistical, communication and array signal processing. Dr. Koivunen is an IEEE Fellow and 2015 IEEE SPS Distinguished Lecturer. He received the 2007 IEEE Signal Processing Society best paper award.