Browsing by Subject "Finite difference time domain method"

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    Microwave imaging with a time-reversed finite-difference time-domain technique
    (Taylor and Francis Ltd., 2014) Bardak C.; Saed M.
    A novel approach to microwave imaging in three dimensions based on time-reversed finite-difference time-domain method (FDTD-TR) is presented. The proposed computationally efficient technique allows the reconstruction of detailed images of scattering objects. Transmissions as well as reflection imaging modalities in the near-field and far-field were investigated. In this study, we implemented the FDTD-TR algorithm in three dimensions using time-reversed convolutional perfectly matching layers as boundaries to truncate the simulation domain. The method works for dielectric as well as conducting objects. The methods capabilities in imaging multiple objects and behind-the-wall imaging are also presented. © 2014 © 2014 Taylor & Francis.
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    Imaging multiple objects with time-reversed FDTD method at microwave range
    (Institute of Electrical and Electronics Engineers Inc., 2015) Bardak C.; Saed M.; Tas̈kln S.
    A simulation technique is presented for imaging multiple objects in microwave region. The proposed technique is based on the time-reversed finite-difference time-domain method (FDTD-TR) in three dimensions. Using this technique, not only the locations of objects but also their detailed images can be obtained. The method is capable of imaging hidden objects with transmission as well as reflection imaging modalities in the nearfield and far-field. The proposed technique is computationally efficient due to using a much smaller data set compared to conventional FDTD-TR imaging techniques where the entire time span of the captured data is reversed. The method was validated using experimental results as well as simulations. © 2015 IEEE.
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    Three-dimensional modelling and terahertz imaging of malignant cells with convolutional time-reversed FDTD method
    (Taylor and Francis Ltd., 2022) Bardak C.
    A novel image reconstruction approach to terahertz pulsed imaging for detecting malignant and fibrous cells within healthy tissue is presented. The non-ionizing effect of the terahertz radiation on healthy tissue makes it a future diagnosis method in medical imaging. The implemented method is based on the convolutional time-reversed FDTD algorithm in the terahertz range. It is computationally efficient and accurately reconstructs images of malignancies from reflected terahertz signals. Besides, the technique is capable of differentiating malignant, fibrous, and fatty cells through the variations of their electrical properties at the terahertz frequency range and well reconstructing their images in 3D. The images created in this method are in high resolution, even for cell-sized malignancies. Furthermore, the proposed technique is compared with conventional terahertz imaging methods and found to have more sophisticated outcomes. © 2022 Taylor & Francis.