This paper reports two techniques for optimizing harmonic termination in power amplifiers. In the jirst technique, the active antenna approach, the antenna element acts as radiator and as part of the output tuning circuit. The second method, based on photonic band-gap (PBG) structure, incorporates a periodic harmonic tuning structure for microstrip lines. In this structure, a periodic 2-D patte...

The diagnosis of many diseases often requires a histological analysis of tissues. Histology analysis compares the microscopic structure of a tissue specimen with an image database containing known physiological and pathological tissue structures. Three new microscopy technologies are developed to complement histology based on novel contrast mechanisms to better visualize and understand tissue s...

The purpose of this paper is twofold. One is to give a survey of our study on the reductions of harmonic bundles, and the other is to explain a simple application in the study of TERP structure. In particular, we investigate the asymptotic behaviour of the “new supersymmetric index” for variation of pure polarized TERP structures.

We address two-dimensional (2D) waveguide arrays where light tunneling into neighboring waveguides may be effectively suppressed by an out-of-phase harmonic modulation of the refractive index in neighboring waveguides at suitable frequencies. Genuine 2D features, such as anisotropic diffraction engineering, diffraction-free propagation along selected directions in the transverse plane, and tunn...

We consider the scattering of time harmonic electromagnetic plane waves by a bounded, inhomogeneous, anisotropic dielectric medium and show that under certain assumptions a lower bound on the norm of the (matrix) index of refraction can be obtained from a knowledge of the smallest transmission eigenvalue corresponding to the medium. Numerical examples are given showing the efficaciousness of ou...

In this paper we completely characterize compact Toeplitz operators on the harmonic Bergman space. By using this result we establish the short exact sequences associated with the Toeplitz algebra and the Hankel algebra. We show that the Fredholm index of each Fredholm operator in the Toeplitz algebra or the Hankel algebra is zero.  2002 Elsevier Science (USA). All rights reserved.

The extraordinary properties of second harmonic generation in negative-index metamaterials, where the Poynting vector and the wavevector have opposite directions are investigated. The ”backward” phase-matching condition results in significant changes in the Manley-Rowe relations and in spatial distributions of the field intensities of the coupled waves. 0 0 z RHM

Refractive index measurements of uniaxial media at wavelengths in the I-Rspectrum are described. The experimental technique makes use of the birefringence to generate interference between the extraordinary and ordinary waves created after an incident plane polarized wave enters the crystal. The use of harmonic generation to convert I-Rradiations to

In this paper, we propose a simple and effective algorithm for frequency estimation and tracking under a harmonic frequency environment. The proposed filter structure contains only one adaptive coefficient and is very efficient for tracking the fundamental frequency of the periodical signal. Index terms Adaptive IIR Notch filter, harmonics, frequency estimation

In this paper the notion of amplitude modulation of chaotic signals is introduced, similar to amplitude modulation of harmonic signal. Necessary conditions for modulation and demodulation of chaotic carrier are discussed. In particular, the type of chaotic carrier is discussed from the point of view of optimal demodulation. Demodulation accuracy estimates are also presented. Index terms – Chaot...