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41.01 Broadcasting and Communication Technologies(BCT)
Displaying 1-25 of 25 articles from this issue
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Pages Cover1-
Published: 2017
Released on J-STAGE: April 02, 2021
CONFERENCE PROCEEDINGS FREE ACCESSDownload PDF (110K) -
Pages Cover2-
Published: 2017
Released on J-STAGE: April 02, 2021
CONFERENCE PROCEEDINGS FREE ACCESSDownload PDF (134K) -
Yuki Kimoto, Takato KudouSession ID: BCT2017-1
Published: 2017
Released on J-STAGE: April 02, 2021
CONFERENCE PROCEEDINGS FREE ACCESSIn this research, we develop and improve a two-dimensional electromagnetic wave simulator using CIP (Constrained Interpolation Profile) method and Java language. In this article, we report the following improvement results. (1) a function of writing information of electromagnetic fields and wave sources to an external file, (2) a function of arranging objects having properties (size, position, medium constants), (3) a function of highlighting a selected object, (4) a function of deleting individually an object with properties, (5) a function of rotating an object, and (6) a function of enlarging and reducing an object by non-equally or equally magnification. With these added functions, it is now possible to change the shape and position of objects, so that complex medium setting can be simplified.View full abstractDownload PDF (556K) -
Yuko SUZUKI, Manabu OMIYASession ID: BCT2017-2
Published: 2017
Released on J-STAGE: April 02, 2021
CONFERENCE PROCEEDINGS FREE ACCESSAccurate modeling of the indoor radio wave propagation is important in order to design and plan wireless LAN (WLAN) networks in the indoor environment. Computer simulations are easy and convenient methods for these purposes. Until now, it was reported that the finite difference time domain (FDTD) method can assess characteristics precisely because of its high ability to model an indoor environment numerically. Our research group applied it to predict the radio wave propagation in a whole floor and a few floors of the office building. It was found from the work that numerical results depended considerably upon the numerical models of indoor environment. An office building consists of primary structures such as concrete walls and floors, and includes furniture in the rooms and reinforcing rods in the concrete walls. The paper carries out numerical electromagnetic field simulations for four distinct numerical models of the same office environment at the frequency of 2442 MHz, and discusses a relationship between the numerical model and its prediction accuracy.View full abstractDownload PDF (1006K) -
Matsumi WADA, Takafumi FUJIMOTO, Takashi TAKENAKASession ID: BCT2017-3
Published: 2017
Released on J-STAGE: April 02, 2021
CONFERENCE PROCEEDINGS FREE ACCESSIn this paper, a breast cancer detection system is proposed. The system consists of 24 wideband printed inverted-F antennas. In order to cover the frequency range from 0.5GHz to 3.5GHz, two antennas with frequency range from 0.5GHz-1.2GHz and from 1.2GHz to 3.5GHz are designed. The reflection and transmission coefficients of the wideband printed inverted-F antennas are compared to the conventional one. The proposed system has uniform reception level from 0.6GHz to 4.0GHz.View full abstractDownload PDF (802K) -
Mitsuo TAGUCHI, Ryo YAMAGUCHISession ID: BCT2017-4
Published: 2017
Released on J-STAGE: April 02, 2021
CONFERENCE PROCEEDINGS FREE ACCESSIn order to realize the thin reception antenna for the terrestrial television broadcasting, the parasitic rectangular loop is located above the previously reported, ultra low profile inverted L antenna on a finite conducting plane. The antenna size is 60 mm by 254 by 100 mm, the return loss less than -10dB is satisfied at the frequencies from 470 MHz to 710MHz. The directivity becomes 3.82 dBi to 6.54dBi.View full abstractDownload PDF (1213K) -
Yuki TANAKA, Eisuke NISHIYAMA, Takayuki TANAKA, Ichihiko TOYODASession ID: BCT2017-5
Published: 2017
Released on J-STAGE: April 02, 2021
CONFERENCE PROCEEDINGS FREE ACCESSWe have proposed a novel 2-dimensional beam steering antenna whose beam direction is controlled by the amplitude ratio of signals fed to an in-phase/anti-phase triple-feed antenna. In this antenna, the amplitude ratio of the input signals is converted to the phase difference between two pairs of antenna elements using a magic-T. Here, the phase difference between the two signals fed to the magic-T has to be 90 degrees. In this paper, performance variation of the proposed beam steering antenna with respect to the input phase error is theoretically and numerically examined. It is found that the input phase error does not affect to the main beam direction but the antenna gain degrades.View full abstractDownload PDF (615K) -
Mitsuo TAGUCHI, Shintaro UTOSession ID: BCT2017-6
Published: 2017
Released on J-STAGE: April 02, 2021
CONFERENCE PROCEEDINGS FREE ACCESSThe wireless power transmission system with the inverted L antennas formed by the coplanar waveguide is proposed and numerically analyzed. The end of center conductor of coplanar waveguide is extended so that the shape of antenna becomes rectangle. The design frequency is 2.45GHz. The size of the rectangular conductor plane is 48mm by 54mm, and height of the antenna element is 1.03mm. When the distance between transmitting and receiving antennas is 10 mm, the return loss frequency bandwidth less than -10dB is 10MHz and the same time, the power transfer efficiency becomes 97.57 %. The power transfer efficiency is studied in the case of the displacement of transmitting and receiving antennas.View full abstractDownload PDF (1022K) -
Mitsuo TAGUCHI, Keiya KAWASHIMA, Koya TAKATASession ID: BCT2017-7
Published: 2017
Released on J-STAGE: April 02, 2021
CONFERENCE PROCEEDINGS FREE ACCESSThe coplanar waveguide installed planar dipole antenna is proposed and numerically analyzed. The design frequency is 300 MHz. The coplanar waveguide is located from the center point to the offset feed point on the dipole antenna. The input impedance and radiation characteristics of this antenna is almost same as those of the offset fed planar dipole antenna. In the numerical analysis, the electromagnetic simulator WIPL-D based on the Method of Moments is used.View full abstractDownload PDF (1280K) -
Keisuke Eguchi, Takeshi FukusakoSession ID: BCT2017-8
Published: 2017
Released on J-STAGE: April 02, 2021
CONFERENCE PROCEEDINGS FREE ACCESSNegative Impedance Converter (NIC) have received much attention to improve the restriction of antenna gain-bandwidth tradeoff relationship. However, a significant problem with NIC is the potential instability of unwanted oscillation due to the presence of positive feedback. For solving this problem, we propose a NIC circuit technique which is stable and improves bandwidth of electrically small antennas.View full abstractDownload PDF (627K) -
Takahiro INO, Eisuke NISHIYAMA, Ichihiko TOYODASession ID: BCT2017-9
Published: 2017
Released on J-STAGE: April 02, 2021
CONFERENCE PROCEEDINGS FREE ACCESSCircularly polarized antennas based on a new principle using a double balanced multiplier are proposed to achieve small and wideband antennas. The double balanced multiplier is formed by connecting four diodes in a star configuration and it realizes 90° phase difference between two orthogonal modes by controlling the bias voltage. Therefore, circular polarizations are obtained. RHCP and LHCP can be switched by the polarity of the bias voltage. In this paper, nonlinear characteristics of DBM integrated circularly polarized antenna is experimentally investigated.View full abstractDownload PDF (717K) -
Takumi HIRONAKA, Tsuyoshi MATSUOKA, Masato OGATASession ID: BCT2017-10
Published: 2017
Released on J-STAGE: April 02, 2021
CONFERENCE PROCEEDINGS FREE ACCESSThis paper presents the measurement of radio wave of UHF band penetrating into a building. The UHF wave signals are measured in the indoor environment and the received level contour maps are depicted by using the measurement data. And the cumulative distribution of received signal level are evaluated at the measurement points, which are at Line of Sight or Non Line of Site. The characteristics of UHF wave propagation in the building are discussed by those results.View full abstractDownload PDF (1247K) -
Mitsuo TAGUCHI, Kazuki EGASHIRASession ID: BCT2017-11
Published: 2017
Released on J-STAGE: April 02, 2021
CONFERENCE PROCEEDINGS FREE ACCESSA 575- MHz rectifying antenna (rectenna) composed of a ultra low profile inverted L antenna and a parasitic conducting plane is proposed and numerically analyzed. The rectenna receives the electromagnetic wave of the television broadcasting of 30 channel. The design frequency is 575 MHz. The antenna size is 281 mm by 180 mm by 18 mm. At the design frequency, the directivity becomes 7.90 dBi and the input impedance is 212.2+j96.6 Ω．View full abstractDownload PDF (1054K) -
Mitsuo TAGUCHI, Yuta SHIMOI, Takafumi FUJIMOTOSession ID: BCT2017-12
Published: 2017
Released on J-STAGE: April 02, 2021
CONFERENCE PROCEEDINGS FREE ACCESSThe microstrip antennas excited by the unbalanced fed inverted L antenna, the L probe, and the coaxial feed are numerically analyzed. The input impedance, the directivity and the near field distributions are compared. The design frequency is 2.45 GHz. In the numerical analysis, the time domain solver of the electromagnetic simulator WIPL-D based on the Method of Moments is used.View full abstractDownload PDF (521K) -
Takuma TSURUOKA, Takafumi FUJIMOTO, Yoichi ISHIZUKA, Tomoyuki FUJISHIM ...Session ID: BCT2017-13
Published: 2017
Released on J-STAGE: April 02, 2021
CONFERENCE PROCEEDINGS FREE ACCESSA circularly polarized small microstrip antenna is proposed for wireless sensor network. One pair of crank-shaped slit is inserted at each edge of patch conductor to reduce the antenna size and radiate circularly polarized wave. The antenna is fed by a coaxial feed at the patch conductor directly. The |S11| and axial ratio of the antenna by an L-probe feed are compared to those by a direct feed at patch conductor. The proposed antenna satisfies the specification of the bandwidth (2.401GHz-2.481GHz) of -10dB-|S11| and 3dB-axial ratio. The antenna radiates circularly polarized wave with wide beamwidth.View full abstractDownload PDF (583K) -
Daiki HISATOMI, Takafumi FUJIMOTOSession ID: BCT2017-14
Published: 2017
Released on J-STAGE: April 02, 2021
CONFERENCE PROCEEDINGS FREE ACCESSBroadband and high gain printed rectangular monopole antenna with a reflector and a parasitic element is proposed. The relationships between the geometric parameters and the simulated antenna characteristics (return loss and gain in the +z direction) are investigated. The simulated bandwidth of 10dB return loss is from 2.31GHz～4.18GHz (57.5%). The simulated bandwidth satisfies the specification of the impedance bandwidth in WLAN and WiMAX applications. The gain of the antenna is from 3.8dBi to 10.4dBi in the +z direction in the frequency band. The proposed antenna has the broadband characteristic due to the parasitic element.View full abstractDownload PDF (543K) -
Nobuhiro IMAIZUMI, Takeshi FUKUSAKOSession ID: BCT2017-15
Published: 2017
Released on J-STAGE: April 02, 2021
CONFERENCE PROCEEDINGS FREE ACCESSWe proposed a low-profile loop antenna that radiating vertical polarization with bi-directional bean pattern. Previous antenna has side lobes at 30 degrees and 330 degrees in vertical plane resulting in radiating parallel direction to the ground plane. So, we proposed a low profile surface antenna using a loop element to decrease the side lobes.View full abstractDownload PDF (1156K) -
Yoshiaki FURUKAWA, Eisuke NISHIYAMA, Ichihiko TOYODASession ID: BCT2017-16
Published: 2017
Released on J-STAGE: April 02, 2021
CONFERENCE PROCEEDINGS FREE ACCESSIn this paper, we propose a polarization switchable active antenna integrating Gunn oscillators. The proposed active antenna is composed of two Gunn oscillators, a ring slot antenna and a polarization switching circuit using four diodes. The polarization angle switching function of a prototype antenna is experimentally demonstrated. The antenna can be applied to a transmission antenna for a spatial modulation system using polarization.View full abstractDownload PDF (591K) -
Hiroki USHIRODA, Eisuke NISHIYAMA, Ichihiko TOYODASession ID: BCT2017-17
Published: 2017
Released on J-STAGE: April 02, 2021
CONFERENCE PROCEEDINGS FREE ACCESSWe have proposed a new spatial modulation system using polarizations, and several advanced planar antennas have been also examined to achieve the spatial modulation system with simple configurations. So far, an active array antenna which integrates a 4-patch microstrip array antenna and Gunn oscillator has been experimentally evaluated. In this paper, a 12-element microstrip array antenna integrated with a Gunn oscillator is proposed and evaluated. The designed polarization angle and 25-dB cross-polarization suppression were obtained. The cross-polarization suppression was 10-dB better than that of 4-patch microstrip array antenna.View full abstractDownload PDF (664K) -
Koichi FURUYA, Takeshi FUKUSAKOSession ID: BCT2017-18
Published: 2017
Released on J-STAGE: April 02, 2021
CONFERENCE PROCEEDINGS FREE ACCESSA broadband circularly polarized (CP) reflectarray antenna is proposed. By removal of the four corners of the finite square reflectarray, radiation from surface wave on the array is reduced at the corners. Furthermore, a design way to control the surface wave by keeping the ground plane square is presented. As a result, the 3-dB axial ratio (AR) bandwidth of 27% can be obtained at the center frequency. Good agreement between simulated and measured results is achieved.View full abstractDownload PDF (2445K) -
Natsuki ONOUE, Takafumi FUJIMOTOSession ID: BCT2017-19
Published: 2017
Released on J-STAGE: April 02, 2021
CONFERENCE PROCEEDINGS FREE ACCESSIn this paper, a printed inverted-F antenna for circular polarization is proposed. A rectangular element is loaded at the feeding line perpendicularly. It is shown that the axial ratio and the impedance matching can be tuned by adjusting the length of the vertical element and the length of the additional rectangular element, respectively. The operational principle for circular polarization is explained using the electric current distributions. The simulated axial ratio and the return loss agree with the measured results. The proposed antenna’s size is 0.32λc×0.21λc (λc is the wavelength at the center frequency) and it is useful as the compact and planar antenna for circular polarization in the ISM band.View full abstractDownload PDF (1145K) -
Eisuke HanadaSession ID: BCT2017-20
Published: 2017
Released on J-STAGE: April 02, 2021
CONFERENCE PROCEEDINGS FREE ACCESSBy introducing a “video image information system for operation”, many of large-scale Japanese hospitals record the situation of the surgical operation as video and enabled edit and distribution. The purposes of using this system include “grasp of the advance situation of an operation”, “creation of the educational/study materials by edit”, “preservation as data for information disclosure”, and “preservation as a measure against a trial.” In this paper, I will show the expectation towards image quality and future required for a system while introducing the composition and the function of a surgery video image information system.View full abstractDownload PDF (469K) -
Junichi Honda, Takuya OtsuyamaSession ID: BCT2017-21
Published: 2017
Released on J-STAGE: April 02, 2021
CONFERENCE PROCEEDINGS FREE ACCESSIn airport surveillance radar for civil aviation, Multi-Static Primary Surveillance Radar (MSPSR) has been expected to be used as a conventional primary surveillance radar (PSR) alternative. MSPSR which is classified into passive radar, is able to use not only the present aviation signals but also other sources. Focusing on the digital terrestrial television broadcasting (DTTB) which is always present and has relatively high output powers, we have been investigating a new surveillance system. We have so far reported the principle of the surveillance system which estimate the aircraft position by using DTTB signal delays. In this paper, we discuss the performance of the proposed system in comparison of automatic dependent surveillance -broadcast (ADS-B).View full abstractDownload PDF (1770K) -
Tomokazu ISHIHARA, Shizuka KARASAWA, Satoshi WATANABE, Yasuhito MORITA ...Session ID: BCT2017-22
Published: 2017
Released on J-STAGE: April 02, 2021
CONFERENCE PROCEEDINGS FREE ACCESSTV Asahi, distribute and transmit signals between inside and outside the company at the Signal Distribution, Routing and Remote control Center. In recent years, with the diversification of IP transmission and the increase in the forms of media such as BS Asahi, CS TV-ASAHI Channel, AbemaTV and internet media, the number of I / O signals handled is rapidly increasing. For the purpose of operating the number of circuits more efficiently 24/7 with a current number of employees, this system was designed and developed from 2013.View full abstractDownload PDF (1137K) -
Pages 89-
Published: 2017
Released on J-STAGE: April 02, 2021
CONFERENCE PROCEEDINGS FREE ACCESSDownload PDF (130K)
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