A new approach to use of the multipole expansion method in eletromagnetic scattering problems.

Hızal, Altunkan


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Cosar, M. B.; Aydogdu, G. H.; Batman, H.; Ozhan, A. E. S. (2016-05-13)
Zinc selenide optical substrates have high transparency within the 0.5- to 14.0-mu m wavelength range. This makes them an attractive candidate for multiband imaging applications in optical components. In order to minimize reflection loss in visible, near-infrared, and mid-infrared applications, zinc selenide lenses are coated with multi-layered oxide thin films by physical vapor deposition method or ion beam deposition. In this study, a four-layer anti-reflective filter at 1.064 gm and between 3.6 and 4.9 g...
Prediction of Vibro-Acoustic Response of Enclosed Spaces by Using Structural Modification Techniques
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Low frequency noise caused by vibrating panels can become a problem for vehicles from NVH standpoint. The vibro-acoustic analysis of a simplified vehicle model is presented in this study. Analysis of vibro-acoustic behavior includes frequency response analysis of structure by Finite Element Method (FEM) and sound pressure level (SPL) prediction of the cabin interior by Boundary Element Method (BEM). The structural design of the vibrating panels can be modified by adding stiffeners to improve the acoustic fi...
A conceptual evaluation of frequency diverse arrays and novel utilization of LFMCW
Eker, Taylan; Demir, Şimşek; Department of Electrical and Electronics Engineering (2011)
Phased array based systems have extending applications in electronic warfare, radio astronomy, civilian applications with technological advancements. The main virtue offered by these systems is the creation of agile beams with utilization of phase shifting or delay elements. In fact, the desire for flexible steering comes with a cost. Frequency Diverse Array (FDA) concept is another approach to beam steering problem. In this context, the subsequent antenna elements are fed with stepped discrete frequencies ...
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Çelebi, Utku; Candan, Çağatay; Department of Electrical and Electronics Engineering (2020-8)
A computationally efficient method for the fundamental frequency estimation of a group of harmonically related complex sinusoids is given. To this aim, an efficient frequency estimation method for single tone complex sinusoids is adapted to the harmonic frequency estimation problem. The main idea of the suggested Fast Fourier Transform based method is the frequency estimation of individual complex sinusoids after the removal of the interference due to other harmonics. After several iterations of estimation ...
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A method for the frequency estimation of complex exponential signals observed under additive white Gaussian noise is presented. Unlike competing methods based on relatively few Discrete Fourier Transform (DFT) samples, the presented technique can generate a frequency estimate by fusing the information from all DFT samples. The estimator is shown to follow the Cramer-Rao bound with a smaller signal-to-noise ratio (SNR) gap than the competing estimators at high SNR.
Citation Formats
A. Hızal, “A new approach to use of the multipole expansion method in eletromagnetic scattering problems.,” Ph.D. - Doctoral Program, Middle East Technical University, 1970.