All issues
Predecessor
23.6
Displaying 1-18 of 18 articles from this issue
- |<
- <
- 1
- >
- >|
-
Article type: Cover
Pages Cover1-
Published: January 28, 1999
Released on J-STAGE: June 23, 2017
CONFERENCE PROCEEDINGS FREE ACCESSDownload PDF (16K) -
Article type: Index
Pages Toc1-
Published: January 28, 1999
Released on J-STAGE: June 23, 2017
CONFERENCE PROCEEDINGS FREE ACCESSDownload PDF (66K) -
Tomonari URATA, Masayoshi AIKAWA, Eisuke NISHIYAMA, Sigeru EGASHIRAArticle type: Article
Session ID: BFO'99-1/ROFT'99-1
Published: January 28, 1999
Released on J-STAGE: June 23, 2017
CONFERENCE PROCEEDINGS FREE ACCESSIn this paper, the FDTD/FVTD Hybrid method is applied to the 2-dimensional electromagnetic scattering by a perfectly electric conducting cylinder. The FVTD(Finite Volume Time Domain), based on a conformal and unstructured grid is used in the near fields of the scatterer surface, and the FDTD(Finite Difference Time Domain)is used to the surrounding area.View full abstractDownload PDF (423K) -
Kenji HIGASHI, Mitsuo TAGUCHI, Takafumi FUJIMOTO, Kazumasa TANAKAArticle type: Article
Session ID: BFO'99-2/ROFT'99-2
Published: January 28, 1999
Released on J-STAGE: June 23, 2017
CONFERENCE PROCEEDINGS FREE ACCESSAmong the computer programs for the analysis of wire antenna and conducting plate, designed to run on personal computer, WIPL, NEC2 and Fidelity are compared. WIPL and NEC2 are programs based on the method of moment applied to the electric field integral equation. Fidelity is the FDTD program. A monopole antenna mounted on the square conducting plate is calculated by using these programs. The monopole is fed at its base. The relative error of input impedance calculated by these programs are compared and discussed.View full abstractDownload PDF (347K) -
Toshiaki IMADA, Eisuke NISHIYAMA, Masayoshi AIKAWAArticle type: Article
Session ID: BFO'99-3/ROFT'99-3
Published: January 28, 1999
Released on J-STAGE: June 23, 2017
CONFERENCE PROCEEDINGS FREE ACCESSThe HFSS is useful for solving electromagnetic problems. This method is based on the finite element method. HFSS is software of very simple for operation. In this paper, characteristics of microstrip antenna, a impedance transformer and a power divider are analyzed by using HFSS.View full abstractDownload PDF (590K) -
Hideaki SOMIYA, Mitsuo TAGUCHI, Takafumi FUJIMOTO, Masanobu HIROSE, Ko ...Article type: Article
Session ID: BFO'99-5/ROFT'99-5
Published: January 28, 1999
Released on J-STAGE: June 23, 2017
CONFERENCE PROCEEDINGS FREE ACCESSTwo element phased array active loop antenna for the digital television receivers are analyzed and their broadband operations are reported. Between the feed point of the passive loop antenna element and the CPW, the silicon transistor 2SC3604 is integrated. When the size of a loop element is 25.8 cm × 12 cm and the distance between two loop elements is 30 cm, the actual gains of more than 13 dBd are obtained for 470 to 590 MHz. In this case, the front-to-back ratio of more than 8 dB are obtained.View full abstractDownload PDF (392K) -
Kentaro YAMASHITA, Jiro IWASHIGE, Yukihiro MARUMINEArticle type: Article
Session ID: BFO'99-6/ROFT'99-6
Published: January 28, 1999
Released on J-STAGE: June 23, 2017
CONFERENCE PROCEEDINGS FREE ACCESSThe electromagnetic waves are scattered by buildings and other obstacles in the urban areas. In this paper, we analyze the electromagnetic fields scattered by a conducting plate on the edge of wedge such as a signbord on the building wall by GTD and show some numerical examples.View full abstractDownload PDF (377K) -
Dala DA, Kazunori UCHIDA, Tosiaki MATSUNAGAArticle type: Article
Session ID: BFO'99-7/ROFT'99-7
Published: January 28, 1999
Released on J-STAGE: June 23, 2017
CONFERENCE PROCEEDINGS FREE ACCESSThis paper is concerned with the electromagnetic field estimation in underground passage and building's lobby. They are assumed to be composed of concrete walls and their floor and ceiling are flat and parallel. However, their structure may be complicated with junctions as well as bends. First we describe about the ray searching algorithm based on the image method. Second we show some rays in underground and building in two-dimensional and three-dimensional ways. Finally we show an example of field distribution in a building.View full abstractDownload PDF (455K) -
Kouji HACHIYA, Masayoshi AIKAWA, Akihide SAKITANIArticle type: Article
Session ID: BFO'99-8/ROFT'99-8
Published: January 28, 1999
Released on J-STAGE: June 23, 2017
CONFERENCE PROCEEDINGS FREE ACCESSWe have studied the simplified DGPS using two GPS receivers, and obtained from 1 to 10m accuracy of point positioning. However, in case when high buildings are nearby, it occurs that sufficient positioning accuracy can't be obtained because of the multipath phenomena. In this paper, the multipath effects in the GPS positioning, and an effective method to reduce the positioning deterioration due to the multipath are described. We also examine the radiation pattern of GPS antenna with metal board which is installed for cutting out the multipath.View full abstractDownload PDF (432K) -
Isamu ARAKI, Mitsuo TAGUCHI, Jong Hwan KIM, Takafumi FUJIMOTO, Kazumas ...Article type: Article
Session ID: BFO'99-9/ROFT'99-9
Published: January 28, 1999
Released on J-STAGE: June 23, 2017
CONFERENCE PROCEEDINGS FREE ACCESSThe complex permittivity and permeability of bincho and bamboo charcoal powder are measured at the frequencies from 90MHz to 2.05GHz by using the complex reflection coefficient method. The measured data are compared with the materials for the electromagnetic wave absorber such as graphitized carbon, acetylene carbon and carbon fiber in silicone rubber.View full abstractDownload PDF (328K) -
Kazunori UCHIDA, Kwang-yeol YOON, Mitsuo TATEIBAArticle type: Article
Session ID: BFO'99-10/ROFT'99-10
Published: January 28, 1999
Released on J-STAGE: June 23, 2017
CONFERENCE PROCEEDINGS FREE ACCESSThis paper is concerned with the fundamental theory of the ray tracing method(RTM)for its application to the wave scattering by two kinds of rough surfaces, one is smooth like sea surfaces and the other is rigit like buildings in urban area. We use Fresnel's reflection coefficients in connection with reflected rays, and for diffacted rays, we employ the approximate diffraction coefficient of the nife edge diffraction. First we check the accuracy of the diffraction coefficient by comparing its results with the analytical solutions based on the Wiener-Hopf technique(WHT). It is shown that we two results are in good agreement. Finally we show some numerical examples of reflected and diffracted rays with regard to the two types of rough surfaces.View full abstractDownload PDF (865K) -
Kousuke TATARA, Masayosi AIKAWA, Eisuke NISHIYAMA, Shigeru EGASHIRAArticle type: Article
Session ID: BFO'99-11/ROFT'99-11
Published: January 28, 1999
Released on J-STAGE: June 23, 2017
CONFERENCE PROCEEDINGS FREE ACCESSIn this paper, circularly polarized microstrip antennas are analyzed using the FDTD method. The characteristics of antennas and electric and magnetic fields around antenna elements can be calculated precisely using the FDTD method. The relations between characteristics of antennas and the field distributions are discussed.View full abstractDownload PDF (488K) -
Eisuke Nishiyuama, Shigeru EGASHIRA, Masayoshi AIKAWAArticle type: Article
Session ID: BFO'99-12/ROFT'99-12
Published: January 28, 1999
Released on J-STAGE: June 23, 2017
CONFERENCE PROCEEDINGS FREE ACCESSIn this paper, a staked microstrip antenna with a wide bandwidth is analyzed using the FDTD method. The staked microstrip antenna with a parasitic element stacked near the fed element has a wide bandwidth. The characteristics of antennas and electric and magnetic fields of around antennas can be calculated accurately using the FDTD method. The frequency characteristics of impedance, gain and radiation patterns of the staked microstrip antenna are analyzed. The near fields around the elements are calculated to investigate the wide-band performance.View full abstractDownload PDF (757K) -
Takayuki TANAKA, Shigeru EGASHIRA, Akihide SAKITANI, Masayoshi AIKAWAArticle type: Article
Session ID: BFO'99-13/ROFT'99-13
Published: January 28, 1999
Released on J-STAGE: June 23, 2017
CONFERENCE PROCEEDINGS FREE ACCESSFor the base station antenna of cellular mobile telephone systems, a beam tilting antenna, which achieves down beam tilting of main beam with smaller cell size, is desired. Such a beam tilting is realized easily by a loaded wire antenna. In this paper, determination method of the loading impedances of the antenna with more than 3 loads for realizing desired tilt angle and low sidelobe level is described.View full abstractDownload PDF (596K) -
Masaaki YAMASAKI, Takehiko TSUKIJIArticle type: Article
Session ID: BFO'99-14/ROFT'99-14
Published: January 28, 1999
Released on J-STAGE: June 23, 2017
CONFERENCE PROCEEDINGS FREE ACCESSA parallel branch wire element which is attached parallel to the antenna element works as a short-circuited coaxial stub used as a loadings element of the antenna. In this paper, the triangular loop antenna with the parallel branch wire was analyzed. The input impedance and the resonance frequency were obtained by using the moment method for the analysis. Calculated results are found to be in good agreement with measurements. As a result, the operation and the effect of the parallel branch wire were clarified. And, the resonance frequency of the triangular loop antenna was able to be reduced up to 64% by the parallel branch wire.View full abstractDownload PDF (492K) -
Osamu HANGAISHI, Takashi YOSHINO, Shiro ITOArticle type: Article
Session ID: BFO'99-15/ROFT'99-15
Published: January 28, 1999
Released on J-STAGE: June 23, 2017
CONFERENCE PROCEEDINGS FREE ACCESSIn order to realize the satellite broadcasting at 21GHz, it is essential to overcome rain attenuation at down-links. A solution is the use of a multi-beam transmitting antenna on board, of which beams are feeded variably; more power to beams pointing to heavily raining areas. This paper describes a parabolic antenna with 6 beams and analyzes its interbeam-interference.View full abstractDownload PDF (655K) -
Kazushi FUJIMOTO, Ken'ichi YUNOKI, Shiro ITOArticle type: Article
Session ID: BFO'99-16/ROFT'99-16
Published: January 28, 1999
Released on J-STAGE: June 23, 2017
CONFERENCE PROCEEDINGS FREE ACCESSIt is difficult to measure sound in the narrow space, such as places about the complicated machine and the complicated object, by a usual microphone. Therefore, a probe microphone is used instead of a usual microphone. But the frequency characteristic of a probe microphone is not uniform and unknown by the experimental data. In this research, at first, the frequency characteristic of a probe microphone was theoretically analyzed with respect to the size of probe etc.. Next, we proposed the system of a probe microphone with the reverse filter for the improvement. As a result of this simulation, the reverse filter is available.View full abstractDownload PDF (567K) -
Article type: Appendix
Pages App1-
Published: January 28, 1999
Released on J-STAGE: June 23, 2017
CONFERENCE PROCEEDINGS FREE ACCESSDownload PDF (77K)
- |<
- <
- 1
- >
- >|