EMCJ99-130 (2000-03)

A Clock Pulse Shaper Using Piezoelectric Transformer

Takahiko Mitani, Shuichi Nitta, Mutoh Atsuo

Tokyo University of Aguriculture and Technology

2-24-16 Naka-cho, Koganei, Tokyo 184-8588 JAPAN

TEL +81-42-388-7096 FAX +81-42-388-7204 FAX E-mail mutoh@tama.or.jp

Abstract: This study proposes the Hybrid Filter using the resonance phenomena of Piezoelectric Transformer to shape the distortion of clock pulse, verifies its performance and establishes the design methods of Hybrid Filter. The proposed Hybrid filter is the band-pass filter utilizing Piezoelectric Transformer and operational amplifier.

Key words: Filter, clock pulse, wave shaper

 

EMCJ99-131 (2000-03)

The Characteristic of an Electromagnetic Ally Coupled Dipole Antenna for Electromagnetic Field Sensors

Hiroyoshi Suga and Takashi Iwasaki

Department of Electronic Engineering

The University of Electro-Communications

l -5- 1 Chofugaoka,Chofu.Tokyo, 182-8585,Japan

phone : 0424-83-2161 ext. 3344

E-mail : suga@snow.ee.uec.ac.jp

Abstract: In this paper, an electromagnetically coupled printed dipole antenna for measuring electromagnetic fields is designed using the FDTD method. The calculated results compare with experimental results .

 It is presented that the half-wavelength resonance can be realized by an offset feed. It is also pointed out that the offset feed printed dipole antenna is useful for electromagnetic field sensors.

Key words: Electromagnetically coupled printed dipole antenna, FDTD method, Offset feed

 

EMCJ99-132 (2000-03)

Estimation of the Current Distribution on a Half Wavelength Dipole Antenna from Near-Electric Field

Kunio GOSHO and Takashi IWASAKI

Department of Electronic Engineering,

The University of Electro-Communications

1-5- 1 Chofugaoka,Chofu ,Tokyo, 182-8585 , Japan

phone : 0424-43-5189 E-mail : gosho@snow.ee.uec.ac.jp

Abstract : In this paper, the current distribution of a half-wavelength dipole antenna is estimated from the electric fields near the antenna by the conjugate gradient method. When the distance between the half-wavelength dipole antenna and an electric probe is 3 to 5cm, the estimated currents obtained from measured electric fields agree with the theoretical results.

Key words: Antenna Current Distribution, Near Electric Field, Conjugate Gradient Method, TRL Ca1ibration

 

EMCJ99-133 (2000-03)

Measuring the Electro Magnetic Shielding Effectiveness of Materials using the Metal Spray Coating Technique

Takeshi Morita, Shozo sumihiro, and Katsuo okumura

Shibaura Institute of Technology

3-9-14 Shibaura Minato-ku. Tokyo, 108-8548. Japan

Phone : 03-5476-2464, Fax : 03-5476-3068  E-mail : okumura@sic.shibaura-it.ac.jp

Abstract: There has been an increasing interest in effect for electronic equipment and human health by electromagnetic fields radiated from the electronic facilities. In order to understand shielding effect of materials using the metal spray coating technique, measurements have been performed using shielded Enclosure. Main results are shown as below ;

(1) In case of paper sprayed coating with metal, the attenuation was almost shown the measurement limit.

(2) It is thought that adhesion of metal and the material influenced strongly characteristics of shielding effectiveness.

(3) It is possible to apply to construction materials from the improvement of fireproof of the material using the metal spray coating technique.

Key words: Electromagnetic wave, Electromagnetic shielding effectiveness, The metal spray coating, Shielded enclosure

 

EMCJ99-134 (2000-03)

Modeling of LSls to Simulate Common-Mode Radiation

Hideki SASAKI, Takashi HARADA, and Toshihide KURIYAMA

EMC Engineering Center, Device Analysis Technology Laboratories, NEC Corporation

l- l, Miyazaki 4-Chome, Miyamae-ku, Kawasaki, Kanagawa

TEL: 044-856-207 1  E -mail: hsasaki@dret.cl.nec.co.jp

Abstract: This paper presents the LSI model to simulate common-mode radiation of printed circuit boards (PCBs) using the FDTD (Finite Difference Time Domain) simulator. Assuming that common-mode radiation is caused because LSIs excite the PCB ground plane, the LSI model have been built, in which the chip and the lead frames of a LSI are modeled respectively by a voltage source and metal wires. To investigate the validity of this model, the measurements of emissions from 4-layer PCBs mounted with a LSI are preformed. The results show that the model, in which the voltage source is placed parallel to the PCB ground plane, can be used to estimate common-mode radiation properties of PCBs. The model can be applied to simulate common-mode radiation of attached-cable PCBs, either. Since it can be used to predict common-mode radiation characteristics of PCBs, using this LSI model would realize the design of LSI packages and PCBs suppressing such radiation.

Key words: common-mode radiation. FDTD, EM simulator, LSI, printed circuit board

 

EMCJ99-135 (2000-03)

A Proposal of Evaluation Method of Ingress Noise for CATV Upstream

Goh Miyamoto1, Atsuhiro Naka2, and Aiichiro Tsuzukul

1Communications Research Laboratory, M.P.T.

2The University of Electro-Communications

4-2-1 Nukui-kita, Koganei-shi, Tokyo 1 84-8795, Japan

Tel. +81~2-327-6312 Fax. +81-42-327-6674  E-mail : miyamoto@crl.go.jp

Abstract: Internet services using CATV lines are getting into stride. But ingress noise degrades upstream transmission quality, so it is necessary to cope with the noise. Though ingress noise is measured using spectrum analyzer generally, this method can't measure impulse noise exactly. We have proposed a new measurement method of ingress noise using amplitude probability distribution. The proposed method avoids the problem mentioned above and has the ability to estimate BER directly.

Key words: CATV, ingress noise, amplitude probability distribution, BER

 

EMCJ99-136 (2000-03)

Degaussing Method for the Structural Materials in the Building

Noboru Ishikawa, Gyo Kajiwara, Akira Okada, and Akira Inubushi

SHIMIZU Corp., EMC Dept., Business Proposal Div

2-3, Shibaura l-chome, Minato-ku, Tokyo 105-8007, JAPAN

Phone: +81-3-5441-1903 E-mail : ishikawa@prop.shimz.co.jp

Abstract: The reinforced steel bar and ,the steel frame are commonly used structural materials for the architectural building and also known as ferromagnetic materials. When they are exposed in the strong magnetic field in the process of production, transportation and so on, it is found that they are sometimes magnetized. The magnetic field generated from these materials causes discoloration of the CRT for the TV-set. In order to prevent this phenomenon, we have investigated the degaussing method for the structural materials using alternative magnetic field. The method proposed in this paper was applied to the floor of the movie studio, and proved to be enough effective to prevent discoloration of the CRT.

Key words: Building, Reinforced steel bar, CRT. Discoloration. Magnetic interference, Degaussing

EMCJ99-137 (2000-03)

A Study of Coverage for Broadcasting in the Millimeter Waves

Kenji MURAKAMI, Hiroynki FURUTA, Fumiyasu SUGlNOSHITA, and Yozo UTSUMI

NHK Science and Technical Research Laboratories

1-10-1 1, Kinuta, Setagaya-ku, Tokyo, 157-8510. JAPAN

TEL:+8 1 -3-5494-2292 / FAX:+81-3-5494-2292 / E-mail:murakamk@strl.nhk.or.jp

Abstract: A coverage must be studied if the broadcasting in the millimeter waves are considered. This paper shows the result of the coverage in the case of low of transmitting/receiving height and low transmitting power obtained by the computer simulation, which takes 3D building data such as height and width into account The "coverage for  household" for fixed receiving station counts 90 percent, and the "coverage on the road" for mobile receiving station results in 70 percent.

Key words: Broadcasting in the millimeter wave, radio-wave transmitting, reflected waves, coverage, coverage for household, coverage on the road