scholarly journals Application of Two-Dimensional Discrete Dipole Approximation in Simulating Electric Field of a Microwave Breast Imaging System

2019 ◽  
Vol 3 (2) ◽  
pp. 80-87 ◽  
Author(s):  
Samar Hosseinzadegan ◽  
Andreas Fhager ◽  
Mikael Persson ◽  
Paul M. Meaney
Keyword(s):  
Electric Field ◽  
Breast Imaging ◽  
Imaging System ◽  
Dipole Approximation ◽  
Discrete Dipole Approximation ◽  
Two Dimensional ◽  
Microwave Breast Imaging

scholarly journals A Discrete Dipole Approximation Solver Based on the COCG-FFT Algorithm and Its Application to Microwave Breast Imaging

2019 ◽  
Vol 2019 ◽  
pp. 1-12 ◽  
Author(s):  
Samar Hosseinzadegan ◽  
Andreas Fhager ◽  
Mikael Persson ◽  
Paul Meaney
Keyword(s):  
Fourier Transform ◽  
Fast Fourier Transform ◽  
Breast Imaging ◽  
Imaging System ◽  
Dipole Moments ◽  
Dipole Approximation ◽  
Discrete Dipole Approximation ◽  
Two Dimensional ◽  
Iterative Solver ◽  
The Matrix

We introduce the discrete dipole approximation (DDA) for efficiently calculating the two-dimensional electric field distribution for our microwave tomographic breast imaging system. For iterative inverse problems such as microwave tomography, the forward field computation is the time limiting step. In this paper, the two-dimensional algorithm is derived and formulated such that the iterative conjugate orthogonal conjugate gradient (COCG) method can be used for efficiently solving the forward problem. We have also optimized the matrix-vector multiplication step by formulating the problem such that the nondiagonal portion of the matrix used to compute the dipole moments is block-Toeplitz. The computation costs for multiplying the block matrices times a vector can be dramatically accelerated by expanding each Toeplitz matrix to a circulant matrix for which the convolution theorem is applied for fast computation utilizing the fast Fourier transform (FFT). The results demonstrate that this formulation is accurate and efficient. In this work, the computation times for the direct solvers, the iterative solver (COCG), and the iterative solver using the fast Fourier transform (COCG-FFT) are compared with the best performance achieved using the iterative solver (COCG-FFT) in C++. Utilizing this formulation provides a computationally efficient building block for developing a low cost and fast breast imaging system to serve under-resourced populations.

Validation of Wavelia Microwave Breast Imaging System Using Mammography Breast Density

2021 ◽  
Author(s):  
Yazan Abdoush ◽  
Angie Fasoula ◽  
Luc Duchesne ◽  
Julio D. Gil Cano ◽  
Brian M. Moloney ◽  
...  
Keyword(s):  
Breast Density ◽  
Breast Imaging ◽  
Imaging System ◽  
Microwave Breast Imaging

Ongoing development of microwave breast imaging system components

2011 ◽  
Author(s):  
Mark Haynes ◽  
Line van Nieuwstadt ◽  
Steven Clarkson ◽  
John Stang ◽  
Clare Ward ◽  
...  
Keyword(s):  
Breast Imaging ◽  
Imaging System ◽  
System Components ◽  
Ongoing Development ◽  
Microwave Breast Imaging

scholarly journals On-Site Validation of a Microwave Breast Imaging System, before First Patient Study

Diagnostics ◽  
2018 ◽  
Vol 8 (3) ◽  
pp. 53 ◽  
Author(s):  
Angie Fasoula ◽  
Luc Duchesne ◽  
Julio Gil Cano ◽  
Peter Lawrence ◽  
Guillaume Robin ◽  
...  
Keyword(s):  
Breast Imaging ◽  
Imaging System ◽  
Imaging Modality ◽  
Disease Diagnosis ◽  
Operating Conditions ◽  
University Hospital ◽  
Radar Signal ◽  
Clinical Test ◽  
Signal Processing Algorithms ◽  
Microwave Breast Imaging

This paper presents the Wavelia microwave breast imaging system that has been recently installed at the Galway University Hospital, Ireland, for a first-in-human pilot clinical test. Microwave breast imaging has been extensively investigated over the last two decades as an alternative imaging modality that could potentially bring complementary information to state-of-the-art modalities such as X-ray mammography. Following an overview of the main working principles of this technology, the Wavelia imaging system architecture is presented, as are the radar signal processing algorithms that are used in forming the microwave images in which small tumors could be detectable for disease diagnosis. The methodology and specific quality metrics that have been developed to properly evaluate and validate the performance of the imaging system using complex breast phantoms that are scanned at controlled measurement conditions are also presented in the paper. Indicative results from the application of this methodology to the on-site validation of the imaging system after its installation at the hospital for pilot clinical testing are thoroughly presented and discussed. Given that the imaging system is still at the prototype level of development, a rigorous quality assessment and system validation at nominal operating conditions is very important in order to ensure high-quality clinical data collection.

scholarly journals Microwave Breast Imaging System Prototype with Integrated Numerical Characterization

2012 ◽  
Vol 2012 ◽  
pp. 1-18 ◽  
Author(s):  
Mark Haynes ◽  
John Stang ◽  
Mahta Moghaddam
Keyword(s):  
Breast Imaging ◽  
Imaging System ◽  
Current Model ◽  
Imaging Systems ◽  
Simple Test ◽  
Ansoft Hfss ◽  
Numerical Characterization ◽  
Microwave Breast Imaging ◽  
System Prototype ◽  
Test Objects

The increasing number of experimental microwave breast imaging systems and the need to properly model them have motivated our development of an integrated numerical characterization technique. We use Ansoft HFSS and a formalism we developed previously to numerically characterize anS-parameter- based breast imaging system and link it to an inverse scattering algorithm. We show successful reconstructions of simple test objects using synthetic and experimental data. We demonstrate the sensitivity of image reconstructions to knowledge of the background dielectric properties and show the limits of the current model.

A miniaturized directional antenna for microwave breast imaging applications

2017 ◽  
Vol 9 (10) ◽  
pp. 2013-2018 ◽  
Author(s):  
Md Zulfiker Mahmud ◽  
Mohammad Tariqul Islam ◽  
Md Naimur Rahman ◽  
Touhidul Alam ◽  
Md Samsuzzaman
Keyword(s):  
Breast Imaging ◽  
Imaging System ◽  
Directional Antenna ◽  
Impedance Bandwidth ◽  
Face To Face ◽  
Antenna Performance ◽  
Directional Radiation ◽  
Lower Frequency Band ◽  
Microwave Breast Imaging ◽  
The Time Domain

A novel compact directional antenna with improved gain is proposed for microwave breast imaging (MBI) applications. The radiating fins are modified by etching several slots to make the antenna compact and enhance antenna performance in terms of bandwidth, gain, efficiency, and directivity. Several parameters are studied and optimized to frequency from 3.1 to 6.5 GHz, which is typically used in the breast imaging system. The electrical length of the antenna is 0.39λ × 0.46λ × 0.01λ at the lower frequency band. The result shows that the antenna exhibits −10 dB impedance bandwidth of 4.3 GHz (2.7–7 GHz) with directional radiation pattern. The peak gain of the proposed prototype is 7.8 dBi and fractional bandwidth is 92%. The time domain results show that the fidelity factor for face to face is 0.92 and for side by side is 0.62, which prove the directivity and lower distortion of the signal. The proposed prototype is successfully simulated, fabricated, and measured.

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