Hongo [1997] analyzed rigorously the plane wave diffraction by a circular disk and a circular hole using a new method based on the Weber-Schafheitlin discontinuous integrals, and obtained a rapidly convergent solution. Uchida et al. [1998a] employed the Wiener-Hopf technique to derive a rigorous solution to the plane wave scattering by a conducting thin plate in an analytically compact form. It is interesting to note that they have investigated the validity of the ray tracing method by comparing the ray solution with the rigorous Wiener-Hopf solution. There is also a paper published by Uchida et al. [1998b] treating a related scattering problem.

The above-mentioned works belong to a class of well-known classical geometries. The authors of these papers have investigated the canonical scattering problems from new theoretical aspects. There have been a number of papers on the scattering by non-classical geometries such as complex resonant structures. These geometries are important in radar cross section (RCS) and target identification studies. Hinata et al. [1996] considered an axially slotted conducting elliptic cylinder in a homogeneous medium, and solved the plane wave diffraction by means of the modified point matching method. They checked the accuracy of the solution by evaluating the relative errors, and showed that this numerical method is useful in treating scattering problems related to canonical two-dimensional geometries. Cavities are also known as typical resonant structures and are important in the RCS analysis. Koshikawa and Kobayashi [1997a] considered a two-dimensional, material-loaded cavity formed by a semi-infinite parallel-plate waveguide with an interior planar termination, and analyzed rigorously the plane wave diffraction using the Wiener-Hopf technique. They presented numerical examples on the RCS and showed that the Wiener-Hopf solution is valid over a broad frequency range. A related paper has been published by Kobayashi and his colleagues, in which they carried out a comparative RCS study of two-dimensional, material-loaded cavities of rectangular and circular cross sections [Koshikawa et al., 1997b].

The integral equation method is a well-known approach for solving wave scattering problems. Ito and Tokumaru [1996] proposed the source and radiation field solution for dielectrics and showed that this method can be effectively employed in the integral equation method. There is also a contribution to the development of new methods for solving scattering problems related to random media. Tateiba and Meng [1996] presented a general approach for solving the wave scattering from a conducting body of arbitrary shape and size in a random medium by introducing the idea called the current generator. It is important to note that chiral and related complex media have been a hot topic in electromagnetic theory in recent years. Xu and Yasumoto [1997] developed cylindrical vector-wave-function representations of electromagnetic fields in a biaxial omega-medium based on the plane wave spectrum representation of the fields and the Fourier expansion for the unknown angular spectrum amplitude. As an application of the proposed method, they analyzed the plane wave scattering by a biaxial omega circular cylinder.

Here we have summarized the recent developments related to the topic area of scattering and diffraction based on several important papers published during 1996-1999. It is hoped that there will be a further progress on the scattering and diffraction theory in the future.

(K. Kobayashi)

Some theoretical inverse techniques have been discussed and evaluated. Takenaka et al. [1997a] developed an iterative approach for reconstructing electrical parameters of stratified lossy media using time-domain reflection and / or transmission data. In this work, the finite-difference time-domain (FDTD) method is used and numerical simulations are performed to reconstruct the images of lossy dielectric slabs with high-contrast permittivity. Ishida and Tateiba [1997] presented a reconstruction method based on a boundary matching technique. It involves an iterative procedure of matching the scattered wave calculated from a certain refractive-index distribution with the measured scattered-wave.

Harada, H. et al. [1996] presents an efficient reconstruction algorithm for the three-dimensional diffraction tomography. The algorithm is based on minimizing a functional which is defined as the square residual error between the measured radiation pattern and the calculated one for an estimated relative dielectric constant. Applying the conjugate gradient method to the problem, they derived an iterative formula for reconstructing the ideal relative dielectric constant. Takenaka et al. [1997b] developed a genetic algorithm approach to determine the widths and locations of strips by scattering data. The distribution of strips is characterized by the local shape function. Numerical examples show the effectiveness of the approach.

Underground imaging and characterization of buried objects is also gathering interest. Application of ground penetrating radar (GPR) are discussed for various field including buried pipe detection in urban area and archaeological survey. Hiraoka et al. [1996] explored electromagnetic detection of cylindrical buried objects from the measurements of scattered field. An iterative inversion procedure for the reconstruction of a strongly scattering object is presented based on the conjugate gradient method. Computer simulations are performed for a lossy and homogeneous dielectric circular cylinder with a priori information about the outer contour of the object. The simulated results demonstrate that the reconstruction of complex refractive index of the object show good agreement with the true profile even for cases where the Born or Rytov approximation fails. Saito et al. [1998] discussed an evaluation technique for the electrical property (complex permittivity) of the soil on the historic sites for subsurface measurement. In this paper, they used a method using the coaxial dipole antenna inserted to the soil. The permittivity of the soil on site can be estimated by comparing the measured data with the theoretical chart.

The technique of visualization of the electromagnetic wave radiation from electronic devices and wireless communication for LAN is increasing its importance. Kitayoshi and Sawaya [1997] proposed a method to visualize source distribution of electromagnetic wave by hologram, in which the receiving antenna is scanned in a planer area. This method is based on the exact Green's function and any approximation such as the Fresnel approximation or the Fraunhofer approximation is not used. They also expanded visualization techniques for observation system to measure a various actual communication signals such as digital cellular telephones and micro-cellular LANs.

(M. Sato)

The finite-element method (FEM) was applied extensively to obtain accurate solutions for a variety of vector-field problems [Koshiba et al., 1997a], [Ohkawa et al., 1997], [Saitoh et al., 1998]. The FEM was often combined with other existing techniques in order to widen the range of application [Koshiba and Tsuji, 1996], [Niiyama et al., 1998], [Tsuji, Y. et al., 1997].

A perfectly matched layer (PML) absorbing boundary condition (ABC) for dispersive media was proposed [Uno et al., 1997] and the performance of the PML-ABC for terminating a quasi-TEM mode in a microstrip line was examined in detail [Namiki, 1997].

Integral equation methods were employed in solving the problems of a transmission line [Nakamura et al., 1998], an antenna with a complex geometry [Ochi et al., 1996], and of a wide class of scattering and diffraction.

The modal expansion approaches were utilized for the numerical solution of boundary value problems such as a body of revolution [Kawano et al., 1996], a waveguide with an elliptic geometry [Krasinski et al., 1996], and a multilayer-coated grating [Matsuda and Okuno, 1996].

(Y. Okuno)

The scattering of dipole waves by the finite size reflector which is composed of strips on a grounded dielectric slab has been studied by applying Physical Optics (PO) [Chen et al., 1996]. The accuracy of PO is verified by comparing calculated results with the experimental ones for vertical and horizontal dipoles over a circular reflector. Field patterns of reflector antennas can accurately be obtained by applying either PO or aperture field integration method (AFIM). Uniform equivalent edge currents of PO and AFIM are analytically compared and their equivalence in high frequency is discussed [Oodo et al., 1996]. It is asymptotically verified that the patterns by AFIM are almost identical to those by PO in full angular region, provided that AFIM uses the equivalent surface currents consisting of the geometrical optics (GO) reflected fields from the reflector and the incident fields from the feed source. The necessary conditions of the integration surface in AFIM for the equivalence to PO are also clarified [Oodo et al., 1997a]. Validity of the conditions is numerically confirmed for various reflectors including the polyhedron approximate reflectors. The basic procedure for PO and some examples are given to provide a better understanding of the practical applications [Ando, 1996]. Also examined are the interpretation of PO approximation by Field Equivalence Theorem and the comparisons of PO with other methods such as GTD and AFIM. PO, originally developed for a perfect electric conductor, is extended to arbitrary impedance surfaces [Oodo et al., 1997b]. Uniform PO diffraction coefficients for the impedance surfaces are derived and their high accuracy is verified numerically. Ando et al. [1998] have also conducted the mechanism extraction of PO based upon accurate diffraction coefficients. The surface-to-line integral reduction of PO proposed there is capable of extracting the mechanism of all the high frequency diffraction analysis methods, such as GTD, AFIM and PTD (Physical Theory of Diffraction).

The diffraction by a smooth convex surface is asymptotically calculated by applying the concept based on the Method of Equivalent Edge Currents (EEC) [Nishimoto et al., 1996]. The equivalent line currents for creeping rays which are derived from the diffraction coefficients of the Geometrical Theory of Diffraction (GTD) are used. By evaluating the radiation integral containing these equivalent line currents, the creeping ray contribution which is effective within the caustic region is obtained. The validity of this method is confirmed by comparing with the exact solution for a perfectly conducting sphere of radius a. The advantage of this method is the validity of it in the caustic region of the creeping rays where the GTD solution is invalid.

(T. Ishihara)

Hosono [1995] has studied the scattering from a circular conducting cylinder with longitudinal slots by combining the modified point matching method (MPMM) with the fast inversion of Laplace transform method (FILT). MPMM is at least by the half order of the simultaneous equations to be solved under the same conditions of accuracy as compared to the conventional point matching method(PMM).

Ohnuki et al. [1996] has investigated the responses of a parallel plate waveguide cavity by the combination of PMM taking into account the edge condition and FILT. Ohnuki et al. [1998] have also applied the same method to the analysis of the scattering by a parallel plate waveguide cavity with the iris. By using wavelet transforms, Nishimoto and Ikuno [1997] have analyzed the scattering data from radar targets; a conducting cylinder, two parallel conducting cylinders, a parallel-plate waveguide cavity, and a rectangular cavity in the underground. In the resulting time-frequency displays, the scattering mechanisms including specular reflection, creeping wave, resonance, and dispersion are clearly observed and identified.

(T. Yamasaki)

Two non-identical and N identical coupled microstrip lines have been analyzed by using the coupled-mode theory combined with Galerkin's moment method in spectral domain [Yasumoto and Matsunaga, 1997].

Shigesawa et al. [1995] have presented that both bound and leaky dominant modes can propagate simultaneously on most printed-circuit lines, and presence of the nonphysical improper real solution which explains how the simultaneous-propagation effect occurs.

Tsuji, M. et al. [1997] have synthesized the H-plane off-set junction and T-junction components by using the finite element method in which their arbitrary shape is represented by the polar coordinates. The 3D finite-element method have been applied to a design approach for a compact and low-loss transition between metal waveguide and rectangular dielectric one [Mizuno et al., 1996], and a dielectric-waveguide Y branch of open structure [Tsuji, M. et al., 1996]. Return loss properties of microstrip line tapers of linear and raised cosine types have been analyzed by using the mode matching procedure for the waveguide model [Shirasaki, 1996].

Yamamoto et al. [1998] have effectively analyzed the characteristics of tilted straight optical waveguides by using the fast-Fourier transform beam propagation method (BPM). The improved finite-difference BPM have been presented to analyze eigen modes of step-index optical waveguides [Shibayama et al., 1998b] and the pure bending loss of a bent step-index slab optical waveguide [Yamauchi et al. 1996b], and the phase adjustment effect of a lensed core fiber [Yamauchi et al. 1998]. Kameda et al. [1997] have analyzed the characteristics of the device length and the bandwidth of coupled optical fibers by using the improved point matching method.

A scalar finite-difference time-domain method have been formulated in order to analysis a circularly symmetric optical waveguide with longitudinal discontinuities [Yamauchi et al., 1997b]. Miyazaki [1996] have proposed the integral equation method using conformal mapping and Green's function and have obtained the optimum tapered junction of optical circular waveguide.

(K. Atsuki)

A new type of circular polarization antennas was proposed by Matsuzawa and Ito [1997] using a coplanar waveguide structure which is suitable to active antennas. The antenna pattern control to reduce the absorbed energy to human body was shown by Yuan and Sawaya [1998] adding a parasitic element to inverted F antenna. A parasitic element applied to inverted F antenna was also effective to wider the frequency bandwidth of a small antenna [ Nakano et al. 1998]. As for the small loop antenna, Muramoto et al.[1997] presented a polarization switching antenna by adopting active devices such as MOSFET. A small slot antenna installed in the belt of a wrist-watch type pager was developed by Okano and Ito [1997]. Ando et al. [1998b] presented a mechanism which can maintain the antenna orientation up-right by using electromagnetically-fed patch antenna and showed effective to reduce the polarization loss due to the inclination of a hand-set telephone. In the field of mobile communications or personal communications, some compact base-station antennas were proposed and analyzed by Ogawa,K. and Uwano [1996]. Conical beam antennas for mobile satellite communications terminals were also developed by Kawakami et al [1997].

An active antenna element for television receivers by Taguchi, M. and Fujimoto [1998] and a cavity-backed slot antenna for the application to spacetenna by Hikage et al.[1998] were also reported. Efficient optical antennas with shaped surfaces were proposed, and characteristics limitation due to mechanical error was clarified by Takano, T. et al. [1997].

Active integrated antenna arrays for spatial power combining in millimeter wavelength region was presented by Kawasaki [1997]. An active phased array antenna for mobile satellite communication terminals at Ka-band was reported by Tanaka et al.[1998a]. This array consists of 168 microstrip antennas with MMIC phase shifters and MMIC LNAs. Switching antennas with multiple beams for broadband wireless systems in the multimedia era are becoming important, and several practical antennas have been presented by Maruyama et al.[1997], Uehara et al.[1996] and Seki et al.[1996]. The experimental study of adaptive array antennas for land mobile systems was also conducted and its effectiveness was clarified by Fujimoto, M. et al.[1996].

Waveguide arrays and their feeding circuits were studied, and high efficiency antennas or simplified geometries have been developed by Ando et al.[1998b] and Sakakibara et al.[1997]. A low-profile Yagi-Uda antenna with an inverted F element and inverted L elements was proposed for the secondary surveillance radar (SSR) by Taguchi, Y. et al.[1997]. A sequential array with higher order mode patch elements and circular polarization array composed of printed strips and slots have been analyzed rigorously and useful data have been presented by Tanaka [1997a]. An array of aperture antennas was proposed to realize an ultra-large antenna of 100 m diameter, and optimized for microwave power transmission by Murao, Y. and Takano [1998].

As for the small antennas, the energy of the handheld antenna absorbed by the human body was measured using the pattern integration method and the good agreement between the measured and numerical results was reported by Chen, Q. et al. [1997]. Kawakami et al.[1998] reported a linear polarized double-wire conical log-periodic spiral antenna for EMC/EMI measurement which is useful above 1GHz, and clarified the site attenuation when this antenna was used.

As for the basic research on microstrip antennas, parallel-palate mode suppression in a slot coupled microstrip antenna was analyzed by Yamamoto and Itoh [1997] and the suppression method was also presented. To enhance the input impedance of the above antenna at resonant frequency, Yamamoto et al.[1998b] proposed the configuration of adding parasitic strip and verified its effectiveness. Nakano et al.[1997] analyzed the Crank-Line microstrip antenna to improve its performance and presented the detailed and effective design data.

Basic contribution to the microstrip antenna with elliptical or perturbed circular shape was given by Fujimoto, T. et al.[1996] and [1998], respectively and wall admittance of these antenna were obtained.

(K. Kagoshima)

Tateiba and Matsuoka [1998] evaluate the scattering cross-section of random medium by analyzing a few radiative transfer equations and make clear the difference of the cross section between EFA, QCA, QCA-CP and their method. Ishii et al. [1997] derive the normalized autocorrelation function of time-varying fluctuations of light scattered multiply from a dense disordered medium within the framework of a photon-diffusion approximation. Harada, Y. and Asakura [1998] demonstrate by computer simulations a temporal correlation function of intensity fluctuations of the light scattered by particles for various factors of particle size and power of illuminating laser beams.

(M. Tateiba)

Ando, M., and M. Oodo [1998a], "Physical optics equivalent edge currents for a half sheet and mechanism extraction of high frequency diffraction analysis," Electromagnetics, vol.18, pp.245-266

Ando, M., J. Hirokawa, T. Yamamoto, A. Akiyama, Y. Kimura, and N. Goto [1998b], "Novel single-layer waveguide for high-efficiency millimeter-wave arrays", IEEE Trans. Microwave Theory and Technique, vol. 46, 6, pp.792-799

Chen, Q., T. Shinohe, K. Igari, and K. Sawaya [1997], "Measurement of radiation efficiency of antennas in the vicinity of human model,"IEICE Trans. Commun., vol. E80-B, 5, pp.709-711

Chen, S., Y. Sato, M. Oodo, and M. Ando [1996], "Physical optics analysis of dipole-wave scattering from a finite strip array on a grounded dielectric slab," IEICE Trans. Electron., vol.E79-C, 10, pp.1350-1357

Fujii, T., and T. Imai [1996], "Indoor micro cell area prediction system using ray-tracing method for mobile communication system," Proc. 1996 Int. Symp. Antennas and Propagation, Chiba, September 24-27, pp.185-188

Fujimoto, M., K. Nishikawa, and K. Sato [1996], "Experimental study of adaptive array antenna system for land mobile Communications," Proc. 1996 Int. Symp. Antennas and Propagation, Chiba, September 24-27, pp.769-772

Fujimoto, T., M. Taguchi, and K. Tanaka [1996], "Surface admittance of elliptical microstrip antenna, " Proc. 1996 Int. Symp. Antennas and Propagation, Chiba, pp.541-544

Fujimoto, T., K. Tanaka, and M. Taguchi [1998], "Analysis of circular microstrip antenna with perturbation segments, " Proc. IEEE AP-S Int. Symp., Atlanta, pp.1594-1597

Furutsu, K. [1998], "Theory of a fixed scatterer embedded in a turbid medium," J. Opt. Soc. Amer. A, vol.15, pp.1371-1382

Han, K. K., K. Yasumoto, K. Uchida, and T. Matsunaga [1998], "FVTD analysis of radiowave propagation in two-dimensional tunnels with arbitrary bending angle," Trans. IEICE, vol.J81-B-II, 8, pp.781-788 (in Japanese)

Harada, H., M. Tanaka, T. Takenaka, and D. J. N. Wall [1996], "An efficient iterative technique for reconstructing three-dimensional dielectric objects," J. of the Japan Society of Applied Electromagnetics and Mechanics, Supplement, vol.4, pp.152-158

Harada, Y., and T. Asakura [1998], "Dynamics and dynamic light-scattering properties of Brownian particles under laser radiation pressure," Pure Appl. Opt., vol.7, pp.1001-1012

Hikage, T., N. Ohno, M. Omiya, and K. Itoh [1998], "Proposal of cavity-backed slot antennas for the microwave energy transmission," Trans. IEICE, vol.J81-B-II, 3, pp.218-225

Hinata, T., H. Hosono, and H. Ono [1996], "Scattering of electromagnetic waves by an axially slotted conducting elliptic cylinder in homogeneous medium," IEICE Trans. Electron., vol.E79-C, 10, pp.1364-1370

Hiraoka, T., M. Tanaka, T. Takenaka, H. Harada, D. J. N. Wall, and T. Furuoku [1996], " Electromagnetic detection of cylindrical buried objects," J. of the Japan Society of Applied Electromagnetics and Mechanics, Supplement, vol.4, pp.28-35

Hirata, A., and T. Shiozawa [1997], "Efficiency enhancement in a Cherenkov laser by a proper permittivity variation," J. Appl. Phys., vol.82, 12, pp.5907-5912

Hirata, A., and T. Shiozawa [1998], "Three-dimensional analysis of a Cherenkov laser via particle simulation," IEEE J. Quantum Electronics, vol.34, 10, pp.1802-1806

Hongo, K. [1997], "Diffraction of an electromagnetic plane wave by circular disk and circular hole," IEICE Trans. Electron., vol.E80-C, 11, pp.1360-1366

Hosono, H. [1995], "Scattering of a modulated pulse by a circular cylinder with longitudinal slots: Reaction in the cylinder," Radio Science, vol.30, 6, pp.1681-1687

Imai, T., and T. Fujii [1996], "Indoor micro cell area prediction system using ray-tracing for mobile communication systems," Seventh IEEE Int. Symp. on Personal, Indoor and Mobile Radio Communications, pp.24-28

Imai, T., and T. Fujii [1997], "Propagation loss in multiple diffraction using ray-tracing," IEEE Antennas and Propagation Soc. Int. Symp., Montreal, July 13-18, pp.2572-2575

Ishida, K., and M. Tateiba [1997], "Reconstruction method of diffraction tomography based on a boundary matching technique," Proc. SPIE, vol.3171, pp.186-197

Ishii, K., T. Iwai, and T. Asakura [1997], "Angular dependence of enhanced backscattering of light by Brownian dynamics in the diffusive transport theory of photons," J. Opt. Soc. Amer. A, vol.14, pp.179-184

Ishizaki, T., T. Kitamura, M. Geshiro, and S. Sawa [1997], "Study of the influence of grounding for microstrip resonators, "IEEE Trans. Microwave Theory Tech., vol.MTT-45, 12, pp.2089-2093

Ito, S., and S. Tokumaru [1996], "Source and radiation field solution for dielectric scatterers - E wave -," IEICE Trans. Electron., vol.E79-C, 10, pp.1338-1344

Kameda, K., S. Furukawa, and T. Hosono [1997], "Characteristics of polarization splitter constructed from coupled two optical fibers," Trans. IEICE, vol.J80-C-I, 11, pp.491-500 (in Japanese)

Kawakami, H., G. Sato, and R. Wakabayashi [1997], "Research on circularly polarized conical-beam antennas," IEEE Antennas and Propagation Magazine, vol.39, 3, pp.27-39

Kawakami, H., G. Sato, R. Wakabayashi, and K. Shimada [1998], "Linear polarized double-wire conical log-periodic spiral antenna for microwave EMC/EMI measurement," Int. Symp. on Electromagnetic Theory, pp.103-105

Kawanishi, T., H. Ogura, and Z. L. Wang [1997], "Scattering of electromagnetic wave from a slightly random dielectric surface - Yoneda peak and Brewster angle in incoherent scattering," Waves in Random Media, vol.7, pp.351-384

Kawano, M., H. Ikuno, and M. Nishimoto [1996], "Numerical analysis of scattering from 3-D perfectly conducting indented objects using the Yasuura method based on the multipole expansion of electromagnetic fields," IEICE Trans. Electron., vol.E79-C, 10, pp.1358-1363

Kawasaki, S. [1997], "High efficient spatial power combining utilizing active integrated antenna technique," IEICE Trans. Electron., vol.E80-C, 6, pp.800-805

Kitayoshi, H., and K. Sawaya [1997], "Electromagnetic-wave visualization for EMI using a new holography method," Trans. IEICE, vol.J80-B-II, 3, pp.284-291

Kondo, A., and K. Kagoshima [1996], "Reflector design and radiation characteristics of a small aperture multibeam antenna " Trans. IEICE, vol.J79-B-II, 11, pp.901-908

Koshiba, M., and Y. Tsuji [1996], "A wide-angle finite element beam propagation method," IEEE Photon. Technol. Lett., vol.8, 9, pp.1208-1210

Koshiba, M., N. Shichishima, K. Ohbuchi, and Y. Tsuji [1997a], "Software for a multilayered surface acoustic wave device based on the finite element method and coupling-of-modes theory," Jpn. J. Appl. Phys., vol.36, 5B, pp.3060-3063

Koshiba, M., T. Kojima, Y. Tsuji, and M. Eguchi [1997b], "Reduction of higher order effects on logic functions of asymmetric nonlinear optical fiber couplers by bandwidth limited amplification," J. Lightwave Technol., vol.15, pp.279-287

Koshikawa, S., and K. Kobayashi [1997a], "Diffraction by a terminated semi-infinite parallel-plate waveguide with three-layer material loading," IEEE Trans. Antennas Propag., vol.AP-45, 6, pp.949-959

Koshikawa, S., D. Colak, A. Altintas, K. Kobayashi, and A. I. Nosich [1997b], "A comparative study of RCS predictions of canonical rectangular and circular cavities with double-layer material loading," IEICE Trans. Electron., vol.E80-C, 11, pp.1457-1466

Krasinski, Z., A. Majewski, and T. Hinata [1996], "Boundary value problem for the electromagnetic fields in elliptical geometry," Electron. Telecommunicat. Quarterly, vol.42, pp.7-18

Kuroda, M., H. Isobe, and H. Kasai [1998], "Electromagnetic wave scattering from a body moving in an arbitrary direction through use of the body fitted grid generation with moving boundary: Quasi-stationary approximation," IEICE Trans. Electron., vol.E81-C, 4, pp.615-617

Kusunoki, A., and M. Tanaka [1997], "Polarization transformation characteristics of a stratified uniaxial chiral slab," IEICE Trans. Electron., vol.E80-C, pp.1428-1433

Li, R., and H. Nakano [1998], "Numerical analysis of arbitrarily shaped probe-excited single-arm printed wire antenna," IEEE Trans. Antennas and Propagat., vol.46, 9, pp.1307-1317

Maruyama, T., K. Uehara, and K. Kagoshima [1997], " Design and analysis of small multi-sector antenna for wireless LAN's made by monopole Yagi-Uda array antenna " Trans. IEICE, vol.J79-B-II, 5, pp.424-433

Matsuda, T., and Y. Okuno [1996], "Numerical evaluation of plane-wave diffraction by a doubly periodic grating," Radio Sci., vol.31, pp.1791-1798

Matsumoto, K., K. Rokushima, and J. Yamakita [1997], "Analysis of scattering of waves by general bianisotropic slabs," IEICE Trans. Electron., vol.E80-C, pp.1421-1427

Matsuzawa, S., and K. Ito [1997], "Circularly polarized slot antenna fed by coplanar waveguide," Trans. IEICE, vol.J80-B-II, 10, pp.871-878 (in Japanese)

Meng, Z. Q., and M. Tateiba [1996], "Radar cross-sections of conducting elliptic cylinders embedded in strong continuous random media," Waves in Random Media, vol.6, pp.335-345

Mitsumoto, H, T. Murata, K. Takano, M. Fujita, S. Tanaka, S. Itoh, K. Shogen, N. Toyama, and H. Miyazawa [1996], "A mobile satellite news gathering system using a flat antenna," IEEE Trans., Broadcasting, vol.42, 3, pp.272-277

Miyahara N., S. Makino, S. Urasaki, and S. Betsudan [1997], "An analysis of beam deflection characteristics of offset parabolic antennas by beam mode expansion," Trans. IEICE, vol.J80-B-II, 11, pp953-962

Miyazaki, Y. [1996], "Analysis of electromagnetic field at tapered junction of optical circular waveguides using conformal mapping," Trans. IEE Japan, vol.116-C, 1, pp.90-95 (in Japanese, AE)

Mizuno, T., M. Tsuji, and H. Shigesawa [1996], "Optimum design of the waveguide-shielded dielectric igage-guide transition by the vector FEM," Trans. IEICE, vol.J79-C-I, 10, pp.406-408 (in Japanese)

Muramoto, M., K. Itoh, and N. Ishii [1997], "Characteristics of a small planar loop antenna," IEEE Trans. Antennas and Propagation, vol.45, 12, pp.1818-1822

Murao, Y., and T. Takano [1998], "An investigation in the design of a transmission antenna and a rectenna with arrayed apertures for microwave power transmission," Trans. of Institute of Electronics, Information and Communication Engineers, vol.J81-B-II, No.1, pp.46-53 (in Japanese)

Naito, I., I. Chiba, S. Makino, and S. Mano [1995], "A design method of feed-array excitation coefficients for array fed reflector type reconfigurable beam antennas," Trans. IEICE, vol.J78-B-II, 12, pp.747-755

Naka, Y., H. Ikuno, M. Nishimoto, and A. Yata [1998], "FD-TD method with PMLs ABC based on the principles of multidimensional wave digital filters for discrete-time modelling of Maxwell's equations," IEICE Trans. Electron., vol.E81-C, 2, pp.305-314

Nakamura, T., S. Matsuura, and H. Kimura [1998], "An analysis of coupled transmission lines with tapered transitions," Trans. IEICE, vol.J81-B-II, 6, pp.632-642

Nakano, H., T. Oka, and J. Yamauchi [1997], "Analysis and measurements for improved crank-line antennas," IEEE Trans. Antennas and Propagation, vol.45, 7, pp.1166-1172

Nakano, H., N. Ikeda, Y. Wu, R. Suzuki, H. Mimaki, and J. Yamauchi [1998], "Realization of dual-frequency and wide-band VSWR performances using normal-mode helical and inverted-F antennas," IEEE Trans. Antennas and Propagation, vol.46, 6, pp.788-793

Nakayama, J., L. Gao, and Y. Tamura [1997], "Scattering of a plane wave from a periodic random surface: a probabilistic approach," Waves in Random Media, vol.7, pp.65-78

Namiki, T. [1997], "The performance of PML absorber for quasi-TEM wave propagating along the microstrip line," Trans. IEICE, vol.J80-C-I, 2, pp.96-99

Nanbu, Y., and M. Tateiba [1996], "A comparative study of the effective dielectric constant of a medium containing randomly distributed dielectric spheres embedded in a homogeneous background medium," Waves In Random Media, vol.6, pp.347-360

Niiyama, A., M. Koshiba, and Y. Tsuji [1998], "Three-dimensional beam propagation analysis of nonlinear optical fibers and optical logic gates," J. Lightwave Technol., vol.16, pp.162-168

Nishimoto, M., and H. Ikuno [1996], "Method of equivalent currents for calculation of surface diffraction by a smooth convex object," IEICE Trans. Electron., vol.E79-C, 10, pp.1321-1326

Nishimoto, M., and H. Ikuno [1997], "Time-frequency analysis of scattering data using the wavelet transform," IEICE Trans. Electron., vol.E80-C, 11, pp.1440-1447

Ochi, H., E. Yamamoto, Q. Chen, and K. Sawaya [1996], "Moment method analysis of antennas composed of conducting wires and planes," Trans. IEICE, vol.J79-B-II, 9, pp.566-573

Ogawa, K., and T. Uwano [1996], "A beam tilt dipole array antenna for indoor mobile applications," IEICE Trans. Electron., vol.E79-C, 5,pp.685-692

Ogawa, M., T. Watanabe, K. Nishikawa, T. Harada, E. Teramoto, and M. Morita [1996], " Mobile antenna system for direct broadcasting satellite," Proc. 1996 Int. Symp. Antennas and

Propagation, Chiba, September 24-27, pp.1197-1200

Ogura, H., and Z. L. Wang [1996], "Surface-plasmon mode on a random rough metal surface - Enhanced backscattering and localization," Phys. Rev. B, vol.53, pp.10358-10371

Ogura, H., and Z. L. Wang [1997], "Stochastic integral equation for rough surface scattering," IEICE Trans. Electron., vol.E80-C, pp.1337-1342

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