ITE Technical Report
Online ISSN : 2424-1970
Print ISSN : 1342-6893
ISSN-L : 1342-6893
35.5
Showing 1-20 articles out of 20 articles from the selected issue
  • Type: Cover
    Pages Cover1-
    Published: February 02, 2011
    Released: September 21, 2017
    CONFERENCE PROCEEDINGS FREE ACCESS
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  • Type: Index
    Pages Toc1-
    Published: February 02, 2011
    Released: September 21, 2017
    CONFERENCE PROCEEDINGS FREE ACCESS
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  • Shimpei AKIMOTO, Kazuyuki SAITO, Masaharu TAKAHASHI, Koichi ITO
    Type: Article
    Session ID: AP2010-162
    Published: February 02, 2011
    Released: September 21, 2017
    CONFERENCE PROCEEDINGS FREE ACCESS
    In Japan, current terrestrial analogue TV broadcasting service will be completely digitized on July, 2011. Frequency allocation plan after the transition had been discussed. As a result, the 35MHz band between 170MHz and 205MHz should be used for public safety by broadband wireless communication system in VHF band shared by multiple public organizations. Therefore, in this study, in order to develop the antenna for broadband wireless communication system in VHF band, the internal antenna within case is designed and considered in the numerical calculation and measurement as fundamental investigation. In addition, to evaluate safety of the humans when they are wearing a wireless terminal for broadband wireless communication system in VHF band, we calculated the SAR in human body exposed to EM waves from the antenna.
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  • Naoto KOGO, Shoji TANAKA, Fumihiro MURAKAMI, Masami SUZUKI
    Type: Article
    Session ID: BCT2011-27
    Published: February 02, 2011
    Released: September 21, 2017
    CONFERENCE PROCEEDINGS FREE ACCESS
    We study on the transmission antennas for the road race live broadcast in order for high reliability of transmission and reduction of the number of the reception antennas. In this report, we examined an array antenna to give high gain toward forward and backward direction of the OB van. On the other hand, there are many types of equipment on the top of the OB van. Therefore, we consider the influence on the radiation patterns of antennas in the computer simulations. As a result, we confirmed the improvement of the antenna gain even the antennas on the OB van.
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  • Susumu NAKAZAWA, Masafumi NAGASAKA, Naoto KOGO, Shoji TANAKA, Yuji ISH ...
    Type: Article
    Session ID: BCT2011-28
    Published: February 02, 2011
    Released: September 21, 2017
    CONFERENCE PROCEEDINGS FREE ACCESS
    We developed a deployable offset-fed reflector antenna with tensioned stainless mesh surface supported by radial ribs for prompt satellite News gathering. For News gathering in emergencies, the portability of the antenna system is important as well as the stability to transmit High-quality video signals. In this paper, we describe the electric performance of a prototype deployable offset-fed reflector antenna.
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  • Yasuyuki MAEKAWA
    Type: Article
    Session ID: AP2010-163
    Published: February 02, 2011
    Released: September 21, 2017
    CONFERENCE PROCEEDINGS FREE ACCESS
    The effects of time delayed diversity techniques on Ku- and Ka-band rain attenuation were investigated, using the radio wave signal levels continuously received from Ku- and Ka-band satellites at Osaka Electro-Communication University (OECU) during 1986-2010. In the Ku-band signals, the improvement of unavailable time percentages of larger than 0.01% due to rain attenuation of 5-10dB is found to be decreased by more than one order, as time delayed diversity of about 30-60min is used, while the same amount of improvement is obtained by 10-20min time delay for unavailable time percentages of less than 0.01% due to rain attenuation of greater than 10dB. In the Ka-band signals, however, about 30-60min time delay is also required to obtain similar improvement for rain attenuation of greater than 10dB. The velocity of rain front passage inferred from the weather charts suggests that the effects of time delayed diversity should correspond to those of site diversity recommended by ITU-R, showing, say, 30-min delay equivalent to about 20-km distance associated with rain area motion. The effects of time delayed diversity are shown to be more conspicuous as the velocity of rain area motion is increased, using the long-term statistics of the Ku- and Ka-band satellite signal levels observed for 21 years from 1986 to 2006.
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  • Rizwan ARIF, Masahiro SHINOZAWA, Ichiro OSHIMA, Yoshio KARASAWA
    Type: Article
    Session ID: AP2010-164
    Published: February 02, 2011
    Released: September 21, 2017
    CONFERENCE PROCEEDINGS FREE ACCESS
    Creation of multipath-rich propagation environment is needed to evaluate the performance of a MIMO communication terminal assuming the operation in a real environment. For this purpose, there are two types of schemes. One is a fading-emulator-based scheme which arranges a number of actual radiation antennas representing scattering objects. The other is a radio echoic chamber named "reverberation chamber" surrounded by 6-plate metallic walls. In this paper, we focus our analysis on our reverberation chamber OTA system which is considered to be inflexible for propagation parameter control such as delay spread. By extending the results given in Ref. [9], we pursue wider range control of delay spread using more radio absorbing sheets without changing other propagation parameter values. Moreover, the size of OTA testing area where the characteristics of multipath propagation environment must be uniform statistically is identified.
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  • Naohisa GOTO
    Type: Article
    Session ID: AP2010-165
    Published: February 02, 2011
    Released: September 21, 2017
    CONFERENCE PROCEEDINGS FREE ACCESS
    The same charge makes electric and magnetic field if charge moves at light velocity. The charge can not move at light velocity, however, the ratio of magnitude of electric field to magnetic field in free space is still the same. This means that we need 10^9 times charge for the magnetic field produced by the current, since the velocity of charge in conductor is 10^<-9> times as light velocity. We show here relations between the current and static magnetic field using equivalent magnetic shell.
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  • Tomoki Murakami, Riichi Kudo, Takeo Ichikawa, Masato Mizoguchi
    Type: Article
    Session ID: AP2010-166
    Published: February 02, 2011
    Released: September 21, 2017
    CONFERENCE PROCEEDINGS FREE ACCESS
    As wireless LAN (WLAN) systems become more widespread, inter-cell interference (ICI) among the access points (APs) is increasing in the overlapping cell. Since the ongoing standardization, IEEE802.11TGac, virtually agreed to increase the channel bandwidth, the overlapping cell problems will become severe due to the limited frequency resource. It is important to combat the overlapping cell problems in the overcrowded house environment like Japanese apartments. This paper evaluates an effective region of two scenarios that increased system throughput in overlapping cell environment. As for Scenario 1, both APs suppress ICI each other using the spatial domain resource sharing. As for Scenario 2, one AP suppresses ICI using spatial domain resource sharing while the other AP transmits signal without using the spatial domain resource sharing. We obtain that effective region of Scenario 1 expends as the number of the transmit antennas increases. In addition, it is found that the system throughput decreases 1.6bit/s/Hz in Scenario 1 and 0.8bit/s/Hz in Scenario 2 by assuming that the variance of channel state information error is same as that of the noise.
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  • Noorsaliza Abdullah, Yoshihiko KUWAHARA
    Type: Article
    Session ID: AP2010-167
    Published: February 02, 2011
    Released: September 21, 2017
    CONFERENCE PROCEEDINGS FREE ACCESS
    We have proposed an adaptive antenna of VHF band for the vehicle using the defogger. The Defogger is used as the shared aperture by implementing several ports. In addition, by introducing the ESPAR concept, adaptive beam pattern can be formed with single receiving channel. We have confirmed by numerical simulation and experiments that the proposed antenna has broadband characteristics and the degradation due to the resistivity of defogger material was negligible.
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  • Yu TAKEDA, Kazuhiro IKARASHI, Qiang CHEN, Kunio SAWAYA, Tomoyuki SATO
    Type: Article
    Session ID: AP2010-168
    Published: February 02, 2011
    Released: September 21, 2017
    CONFERENCE PROCEEDINGS FREE ACCESS
    To design an optimum indoor receiving antenna for digital terrestrial television broadcasting, it is necessary to evaluate radio wave environment of broadcasting wave for indoor reception. In the present report, receivied power of the digital terrestrial broadcasting wave is measured and its distribution is shown in a room. The correlation coefficient between the received powers of two receiving antennas is also evaluated by using the distribution of the received power and assuming two receiving antennas. Finally, the effect of selection diversity reception is obtained by using cumulative distribution function of the received power.
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  • Yoshikazu NARIKIYO, Masayuki TAKADA
    Type: Article
    Session ID: BCT2011-29
    Published: February 02, 2011
    Released: September 21, 2017
    CONFERENCE PROCEEDINGS FREE ACCESS
    We are studying on improvement of ISDB-T HDTV mobile reception technology for expanding reception area. We have proposed a new reception method that has two core technologies. One is 8-branch space diversity reception technology, and the other is iterative decoding technology between Viterbi decoding and Reed-Solomon decoding. We have reported the computer simulation results and laboratories results so far. In this paper, we describe the performance of field experiments by proposed prototype receiver in Kanto area. We compared mobile reception areas with two reception methods: conventional 4-branch space diversity without iterative decoding, and proposed 8-branch space diversity with iterative decoding. The reception area for the proposed method was improved about 5 to 6dB as the reception field strength compared with that for the conventional method.
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  • Koichi OGAWA
    Type: Article
    Session ID: AP2010-169
    Published: February 02, 2011
    Released: September 21, 2017
    CONFERENCE PROCEEDINGS FREE ACCESS
    Maximum ratio combining (MRC) array antennas are commonly used for digital TV terrestrial reception systems, which includes 1-segment TV mobile handsets, portable liquid crystal TV, and automotive full-segment TV receivers. Due to a tight limitation on internal volume in these apparatus, it is difficult to give a space sufficient for installing all antenna elements with a large gain required for showing a high performance as an MRC array. In addition, effects of the human body, especially hands and fingers, operating close to an antenna must be considered in mobile handset TV receivers. These facts often results in significant gain reduction in antenna elements for several MRC branches. However, the criterion with respect to the gain reduction of antennas is not clear for achieving a required system performance. Hence, this paper studies an analysis of the diversity gain of an MRC array for digital TV receivers under unequal branch power condition.
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  • Shinji SUESADA, Yukio NAMBO, Eiji SAJI
    Type: Article
    Session ID: AP2010-170
    Published: February 02, 2011
    Released: September 21, 2017
    CONFERENCE PROCEEDINGS FREE ACCESS
    The transmission loss was measured through the membranous water on radome coated the silica type water-repellent from 1GHz to 18GHz. This water-repellent does not contained fluorine had telling high load of environment biologically, and be able to coat on most of material. This water-repellent has more than 150 degree of the contact angle, and is verify to be efficient for this maicrowave band, since the transmission was maintained as the dry condition of this radome.
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  • Yoshiyuki KINUGAWA, Kazuya SATO, Kuniyuki MOTOJIMA, Masaaki MATSUBARA
    Type: Article
    Session ID: AP2010-171
    Published: February 02, 2011
    Released: September 21, 2017
    CONFERENCE PROCEEDINGS FREE ACCESS
    The nondestructive inspection for crack detection in basic and high accuracy is needed for operating nuclear plant facilities in safety. This report presents a new method of non-contact probing for cracks on metallic board by using antenna. In order to verify availability of this method, we performed numerical analysis and experimental measurement of various length of cracks that exist 20mm away from antenna.
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  • Miki TAKIMOTO, Jun NAKADA, Hiroyasu SATO, Kunio SAWAYA
    Type: Article
    Session ID: AP2010-172
    Published: February 02, 2011
    Released: September 21, 2017
    CONFERENCE PROCEEDINGS FREE ACCESS
    Fresnel lens is well known as a low-weight and thin-structure. In order to use Fresnel lens for passive millimeter-wave imaging, it is necessary to evaluate degradation of focusing property by zoning. In this paper, fundermental characteristics of Fresnel lens such as focusing point and electric field intensity around focal point are numerically analyzed by using two-dimmensional FDTD (Finite-Difference Time-Domain) analysis and compared with the case of aspheric lens. Detailed study of effect of the base thickness of lens on fundermental characteristics is performed, and structure parameters of Fresnel lens having mechanical strength and high electric field intensity are obtained. It is observed that electric field intensity of Fresnel lens around focal point is only 0.5dB less than that of aspheric lens. Fresnel lens designed by FDTD analysis is fabricated and its characteristics are measured confirming the validity of the design based on FDTD method.
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  • Kyoichi IIGUSA, Hiroshi HARADA
    Type: Article
    Session ID: AP2010-173
    Published: February 02, 2011
    Released: September 21, 2017
    CONFERENCE PROCEEDINGS FREE ACCESS
    To evaluate radiation loss and conductor loss which are the cause of deterioration in the wireless electric power transmission, a calculation method of a transmission electric power, a radiated power, and a conductor loss as a ratio to the input electric power is proposed. The dependency of those ratios to the resistance and the reactance of the receiving circuit are clarified for the short distance wireless electric power transmission between small dipoles, and the method to improve the transmitting efficiency is investigated.
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  • Type: Appendix
    Pages App1-
    Published: February 02, 2011
    Released: September 21, 2017
    CONFERENCE PROCEEDINGS FREE ACCESS
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  • Type: Appendix
    Pages App2-
    Published: February 02, 2011
    Released: September 21, 2017
    CONFERENCE PROCEEDINGS FREE ACCESS
    Download PDF (94K)
  • Type: Appendix
    Pages App3-
    Published: February 02, 2011
    Released: September 21, 2017
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