The Finite-Difference Time Domain (FDTD) method is a very useful numerical simulation technique for solving problems related to electromagnetism. However, as the traditional FDTD method is based on an explicit finite-difference algorithm, the Courant-Friedrich-Levy(CFL) stability condition must be satisfied when this method is used. Therefore, a maximum time-step size is limited by minimum cell size in a computational domain, which means that if an object of analysis has fine scale dimensions, a small time-step size creates a significant increase in calculation time. Alternating-Direction Implicit (ADI) method is based on an implicit finite-difference algorithm. Since this method is unconditionally stable, it can improve calculation time by choosing time-step arbitrarily. The ADI-FDTD is based on an Alternating direction implicit technique and the traditional FDTD algorithm. The new method can circumvent the stability constraint. In this thesis, we incorporate Lumped Element and Equivalent Current Source method into the ADI-FDTD. By using them to simulate active or passive device, the application of method will be more widely.

In this thesis the direction of arrival estimation of wideband signals using frequency invariant beamforming method is examined. The difficulty with the direction of arrival estimation of wideband signals is that it is not possible to obtain a single covariance matrix valid for the whole frequency spectrum of the signal. There are various methods proposed in the literature to overcome this difficulty. The common aim of all the methods is to obtain a composite covariance matrix for the overall band of the signal. In this thesis, we concentrate on a method in [12]. This method is based on a beamforming technique that provides frequency invariant beams in the band of interest. Therefore there is no need for frequency decomposition as it is done with the other wideband methods. A comparison of the frequency invariant beamforming method with coherent signal subspace methods and narrow band methods is also given.

We study a novel structure employing the woven continuous carbon fiber (CCF) epoxy composite with high electromagnetic (EM) shielding. The influences of wove type, number and angle of overlapped plates upon the shielding effectiveness (SE) of wove CCF epoxy composite are investigated. The minimum SE of the single, double, and triple plain or balanced twill woven CCF composite plates were measured to be as high as 50 dB, 60 dB, and 70 dB, respectively. More than 100 dB of SE was obtained for the triple overlapped plain wove CCF composite at frequency of 0.9 GHz. The weight percentage of single CCF composite plate required for electronic application was 4.8% only, which was less than one quarter of the carbon fiber (CF) content and the performance of SE was 10 dB higher in comparison with long CF filled liquid crystal polymer composites. The SE calculated theoretically is consistent with that measured by the experiment. We have demonstrated a new woven CCF epoxy composite with high EM shielding. This work may lead to the development of effective shielding for plastic optical transceiver modules to prevent electromagnetic interference (EMI) for use in low cost and lightwave communication systems.

H.264/AVC intra prediction method is an efficient tool to reduce spatial redundancies by using multidirectional spatial prediction modes. In this paper, a novel intra prediction method is designed to improve coding efficiency. Firstly, we propose a direction-distance oriented prediction which considers the distance between the predict value and the reference samples according to the direction of the prediction modes. Secondly, we apply the concept of image restoration by using the projections onto convex sets (POCS) to intra prediction which uses adaptively filtering based on the surrounding reconstructed pixel to predict blocks. The experimental results show that the average bit-rate reduction of 0.75% and PSNR gain improved of 0.119dB are achieved.

Th. Etat--Musique et musicologie--Tours--Univ. François Rabelais, 2001. / Sources et bibliogr. f. 978-1016. Index.

Thèse de doctorat : GESTION : Metz : 2001. / 2001METZ001D. 280 ref.

Thesis (D. Min.)--Ashland Theological Seminary, 2008. / Abstract . Description based on microfiche version record. Includes bibliographical references (leaves 146-152).

Thesis (D. Min.)--Ashland Theological Seminary, 2002. / Abstract. Includes bibliographical references (leaves 138-142).

ITC/USA 2013 Conference Proceedings / The Forty-Ninth Annual International Telemetering Conference and Technical Exhibition / October 21-24, 2013 / Bally's Hotel & Convention Center, Las Vegas, NV / In this paper, a new technique utilizing a scatterer of high dielectric constant in between electrically small antennas to achieve good Direction of arrival (DOA) estimation performance is demonstrated. The phase information of the received signal at the antennas is utilized for direction estimation. The impact of the property of the scatterer on the directional sensitivity and the output signal to noise ratio (SNR) level are studied. Finally the DOA estimation accuracy is analyzed with the proposed technique under the consumption of white Gaussian noise environment.

ITC/USA 2012 Conference Proceedings / The Forty-Eighth Annual International Telemetering Conference and Technical Exhibition / October 22-25, 2012 / Town and Country Resort & Convention Center, San Diego, California / A broadband passive direction finding system utilizing Luneburg lens has been investigated. With the simulated power level distribution at the detectors mounted on a Luneburg lens, both Cramér-Rao bound (CRB) and the root mean square error (RMS) based on the Correlation Algorithm (CA) for the direction of arrival (DoA) estimation have been derived and calculated. Guidelines on how to design the Luneburg lens detecting system have been studied. Finally, as a proof-of-concept demonstration, the DoA performance of a Luneburg lens fabricated using the polymer jetting technology with five detectors 10° equally spaced to receive the azimuth signal from -20° to 20° is demonstrated.