High Resolution Ultrasonic Array Imaging

This project is aimed to develop methods to improve image quality in ultrasonic array imaging using recent model based reconstruction methods for realistic array layouts. The drawback of the traditional delay-and-sum (DAS) based array focusing method---w hich requires the array pitch to be less than half the acoustic wavelength to avoid grating lobes and the element sizes to be small since they are regarded as point sources by the DAS method---is relaxed by this new approach; thus enabling a more flexibl e design of the array layouts. The objective of the project is to further develop and adapt these methods to medical, sonar, sparse arrays, 2D arrays, as well as undersampled linear arrays. Issues that also will be considered are design of robust metho ds for treating model errors, design of optimal input signals for optimizing reconstruction performance, as well as development of methods for designing focusing methods specifically customized to these model based reconstruction algorithms. Furthermor e, since the methods can be computational demanding the project will also include studies in efficient sparse representations as well as development of parallel implementations for large scale problems.