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Predecessor
23.11
Displaying 1-10 of 10 articles from this issue
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Article type: Cover
Pages Cover1-
Published: February 12, 1999
Released on J-STAGE: June 23, 2017
CONFERENCE PROCEEDINGS FREE ACCESSDownload PDF (14K) -
Article type: Index
Pages Toc1-
Published: February 12, 1999
Released on J-STAGE: June 23, 2017
CONFERENCE PROCEEDINGS FREE ACCESSDownload PDF (32K) -
Satoshi IKEDA, Hiroto SAKURADA, Leelaruji Nipha, Yoshiaki MORIYAArticle type: Article
Session ID: ROFT'99-30
Published: February 12, 1999
Released on J-STAGE: June 23, 2017
CONFERENCE PROCEEDINGS FREE ACCESSThe wireless communication is one of important information transfer system in the present day life. The wireless communication can easily construct anytime and anywhere. However, this method receives interference by various phenomena. We shall reports in this time that quasi-periodic phenomenon is seen in the television broadcasting signals on VHF and UHF. This phenomenon is generated by coming flight of the airplane. We observed this phenomenon in Bangkok, Thailand and Kanagawa, Japan. And this phenomenon can calculate on various conditions. The calculation results can explain interference structure accompany many characteristics.View full abstractDownload PDF (657K) -
Yukihiro MARUMINE, Jiro IWASHIGE, Kentaro YAMASHITAArticle type: Article
Session ID: ROFT'99-31
Published: February 12, 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. It is necessary to analyze the electromagnetic waves propagating there for usage of a portable telephone or PHS. In this paper, we calculate the electric fields of the wave which is transmitted from one side of a buiding and reaches the other side over its rooftop. We also consider the influence by the shape of the rooftop obstacle on the propagation characteristics.View full abstractDownload PDF (363K) -
Masatoshi YORITA, Koichi ITOArticle type: Article
Session ID: ROFT'99-32
Published: February 12, 1999
Released on J-STAGE: June 23, 2017
CONFERENCE PROCEEDINGS FREE ACCESSRecently, the demand for the mobile satellite communication is increasing, and many communication services are in the planning stage. Various types of vehicle antennas, which can track the satellite, have been studied. We proposed a simple beam-switching printed array antenna composed of four elements. In this paper, we chose the patch antenna with single-feed, as the circularly polarized printed antenna and we propose a simple beam-switching printed array antenna composed of three elements.View full abstractDownload PDF (802K) -
Hideyuki Arita, Takeshi Kunii, Eijiro Murakami, Hiroyasu Matsui, Toshi ...Article type: Article
Session ID: ROFT'99-33
Published: February 12, 1999
Released on J-STAGE: June 23, 2017
CONFERENCE PROCEEDINGS FREE ACCESSThe FDTD method is effective to the antenna analysis and a lot of study is done. Using the FDTD method, the screen antenna which is constructed by an element on dielectric plate is analyzed. Dielectric constant and thickness of the dielectric plate can be used to modify characteristics of the antenna, that are shown in figures. From the results, we see how the factors contribute to the variation of antenna's characteristic. From the results, those antennas are useful for mobile communications.View full abstractDownload PDF (354K) -
Tomohiro Hon-ya, Takefumi Namiki, Koichi ItoArticle type: Article
Session ID: ROFT'99-34
Published: February 12, 1999
Released on J-STAGE: June 23, 2017
CONFERENCE PROCEEDINGS FREE ACCESSSurface impedance boundary conditions(SIBC)concepts are employed to eliminate the internal volume of lossy objects from scattering calculations. In applications of FDTD they are very important because they can eliminate the use of small cells which are necessary for shorter wavelengths in conducting media. In this report, the propagation characteristics of a microstrip line are calculated. The metal region of the model is set to the medium, which has the finite electric conductivity using the SIBC. The impedance at the surface of the metal is approximated using a summation of causal functions. The approximated impedance is Z-transformed and utilized in the FDTD code.View full abstractDownload PDF (586K) -
Hiromi Kobayashi, Takahiro Miyamoto, Toshio WakabayashiArticle type: Article
Session ID: ROFT'99-35
Published: February 12, 1999
Released on J-STAGE: June 23, 2017
CONFERENCE PROCEEDINGS FREE ACCESSThe problem of coupled microstrip lines through a slot in a common ground plane is analyzed. The slot is divided by many small rectangular slots. S-parameters for each divided slot are obtained by the analytical method which has been used, and S-parameters are obtained by the theory of multihole directional coupler which is constructed by many holes. Experimental results are in agreement with the theoretical results.View full abstractDownload PDF (561K) -
Hiroyuki UNO, Atsushi SHIBANO, Akiyoshi KOJIMA, Osamu MIKAMIArticle type: Article
Session ID: ROFT'99-36
Published: February 12, 1999
Released on J-STAGE: June 23, 2017
CONFERENCE PROCEEDINGS FREE ACCESSThe optical Fiber Bragg Gratings(FBG)have been studied intensively these years, because they are expected to be applied for an Add-Drop Multiplexer(ADM)and a wavelength selecting device at the Wavelength Division Multiplexing(WDM)fiber transmission systems. As one of their characteristics, Bragg reflection wavelength can be changed by applying stress to the grating region. We have clarified that the Bragg wavelength can be easily shifted by using an electrically driven-micro step stage. Based on these fundamental experiments, we investigated its possibility of optical wavelength switching with special sttentions to the extinction ratios for the reflected and transmitted lights, and the switching speed.View full abstractDownload PDF (623K) -
Article type: Appendix
Pages App1-
Published: February 12, 1999
Released on J-STAGE: June 23, 2017
CONFERENCE PROCEEDINGS FREE ACCESSDownload PDF (71K)
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