Adaptive Digital Signal Processing for Spatial and Temporal Sampled Coherent Imaging Systems

University Of Virginia Main Campus, Charlottesville VA

Investigators

Abstract

This research will develop advanced digital signal processing algorithms for specific coherent imaging systems where complex signals are spatially and temporally sampled, and subsequently processed by computers.Modeling of the physics of data acquisition will play a crucial role throughout the signal processing chain,from preprocessing at the sensor level to adaptive processing/beamforming and final image formation.The focal research areas will involve ultra wide band medical ultrasound imaging,and electromagnetic wave imaging in millimeter spectral bands.Millimeter electromagnetic wave imaging could have important anti-terrorism applications such as detection of plastic guns and knives in human body scanning at airports,and surveillance of suspected safe houses,storage areas,and cargos by imaging through walls or crates. In the medical ultrasound area,the research will involve the following specific topics:(1) optimal transmit/receive beam forming for near field dynamic focusing;(2)multiple foci B scan imaging for increasing scan rates;(3).theoretical performance bounds associated with combined random processes of random scatterers and noise.and (4),phase aberration correction algorithms for 3-D systems including new methods for dealing with dispersed aberrators such as fat lobules,membranes,etc.,that can diffract and refract the ultrasound beams.The research in electromagnetic coherent imaging will involve: synergistic adaptation of the statistical ultrasound autofocusing/phase aberration correction concepts to the electromagnetic spectrum;development of millimeter wa e imaging algorithms for surveillance functions such as rapid body scanning and imaging through thin dry medium such as wood,plaster board or stone.The research in all the coherent modalities will involve:development of practical fast converging computer implementations of reconstruction algorithms;extensive simulations,and performance analyses of the new models and algorithms.