ITE Technical Report
Online ISSN : 2424-1970
Print ISSN : 1342-6893
ISSN-L : 1342-6893
26.59
Showing 1-16 articles out of 16 articles from the selected issue
  • Type: Cover
    Pages Cover1-
    Published: September 19, 2002
    Released: June 23, 2017
    CONFERENCE PROCEEDINGS FREE ACCESS
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  • Type: Index
    Pages Toc1-
    Published: September 19, 2002
    Released: June 23, 2017
    CONFERENCE PROCEEDINGS FREE ACCESS
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  • Susumu WADA, Tetsuya WATANABE, Tsuyoshi SIMODA, Hiroaki UEDA
    Type: Article
    Session ID: POFT200280
    Published: September 19, 2002
    Released: June 23, 2017
    CONFERENCE PROCEEDINGS FREE ACCESS
    Digital terrestrial broadcasting service will be started completely after going through the process of re-allocation of analog channels at nominated broadcasting stations and the process of simulcast broadcasting service by digital and analog channels. On the above process, operating channel of transmitting antenna is requested to change for some channels. In order to minimize the construction cost of antenna system, it is strongly requested to apply for various operating frequency by one antenna system as much as possible through the above process. By above reason, it is most important issue for transmitting antenna system to be apply for wide band, not only for horizontal polarization, but also for vertical polarization. This paper describes UHF Wide Band Antenna for vertical polarization which have almost same characteristics as 4L Dual Loop Antenna for vertical polarization through UHF band.
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  • Yasushi IITSUKA, Daisuke SIRAHAMA, Toshiyuki HAGA
    Type: Article
    Session ID: POFT200281
    Published: September 19, 2002
    Released: June 23, 2017
    CONFERENCE PROCEEDINGS FREE ACCESS
    The simple structure quadrifilar helical antenna with a ground plane which has parasitic elements placed in middle of fed elements on the same circumference was investigated in dual-frequency bands. As the results by using the moment method, the dual-frequency band operation is realized if the length of fed elements are 3/4λ at the low frequency, and the parasitic elements are a little shorter than 3/4λ at the high one. The prototype antenna based on these results for GPS applications has good characteristics in terms of return loss, radiation patterns and axial ratio, similar to the simulation.
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  • Hiroshi HATANAKA, Masayoshi NAKANO, Yuu TAKAMI, Takaharu YAMAMOTO, Shi ...
    Type: Article
    Session ID: POFT200282
    Published: September 19, 2002
    Released: June 23, 2017
    CONFERENCE PROCEEDINGS FREE ACCESS
    At introducing digital terrestrial television broadcasting systems, contiguous channel combiners are required. With the combiners, it is difficult to realize low interference level between channels. On the other hands, at satellite stations for digital terrestrial television broadcasting, separate-channel amplifying systems are superior to multi-channels power amplifying systems in the point of practical use and cost, but the accompanying channel combiners have large size and are expensive. This paper presents data of experimental contiguous channel combiners for the systems to resolve these problems.
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  • Koichiro IMAMURA, Hiroyuki HAMAZUMI, Kazuhiko SHIBUYA
    Type: Article
    Session ID: POFT200283
    Published: September 19, 2002
    Released: June 23, 2017
    CONFERENCE PROCEEDINGS FREE ACCESS
    This paper describes a channel equalizer that can equalize multipath longer than the guard interval of OFDM signal. In equalization using SP (Scattered Pilot), detectable delay of multipath is less than one third of a useful symbol duration. This paper proposes an equalization using decisions of all OFDM carriers to detect long-delay beyond the guard interval. The proposal method can detect delay of multipath as long as the useful symbol duration in principle. Then, the channel equalizer can detect and equalize delay of multipath beyond the guard interval up to lOO8μs in the mode 3 of ISDB-T. Laboratory experiments verified the performance of the equalizer.
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  • Kazuaki SUZUKI, Kenichiro HAYASHI, Yoshinori KUNIEDA, Hidekuni YOMO, Y ...
    Type: Article
    Session ID: POFT200284
    Published: September 19, 2002
    Released: June 23, 2017
    CONFERENCE PROCEEDINGS FREE ACCESS
    In digital terrestrial broadcasting, realization of SFN (Single Frequency Network) by broadcast-wave relay is desired. However, when building SFN by broadcast-wave relay, a part of transmitted signal from a transmitting antenna returns to a receiving antenna and, as a result, coupling loop interference occurs. The coupling loop interference not only degrades quality of relay signal but also may cause oscillation. In order to solve the problem, we developed a canceller that suppresses coupling loop interference. Moreover we conducted a field test using the canceller at Hakui relay station established for DTTB (Digital Terrestrial Television Broadcasting).
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  • Mamoru AKIMOTO, Kouichi HARADA, Kazuji WATANABE
    Type: Article
    Session ID: POFT200285
    Published: September 19, 2002
    Released: June 23, 2017
    CONFERENCE PROCEEDINGS FREE ACCESS
    This paper reports on an investigation of a highly-accurate method for estimating the one-minute rain rate distribution for various locations throughout Japan using observed precipitation data collected through the Automated Meteorological Data Acquisition System (AMeDAS). In recent years, there has been an increasing tendency for very hard rain to fall in a short period of time, and the relationship between one-hour and one-minute rain rate distribution has changed in comparison to the one-hour and one-minute precipitation data collected during the past 25 years. As an example of the reflection of this tendency on the highly-accurate method for estimating the one-minute rain rate distribution, we present a method that estimates the one-minute rain rate distribution by supplementing the hourly rainfall data with 10-minute rainfall data and show quantitatively an improvement in the accuracy over existing estimation methods.
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  • Fan-Nian KONG, Zhaofa ZENG, Motoyuki SATO
    Type: Article
    Session ID: POFT200286
    Published: September 19, 2002
    Released: June 23, 2017
    CONFERENCE PROCEEDINGS FREE ACCESS
    In this paper we derive that a Vivaldi antenna behaves much the same as a TEM horn. However a Vivaldi antenna is built on a print circuit board, while the TEM horn is basically a 3D antenna. Hence a Vivaldi antenna can be easily manufactured and has more solid mechanical structure than a TEM horn antenna. We can say that we have found a new way to build a simple structure TEM horn antenna. We have used the method of designing a TEM horn antenna to design a Vivaldi antenna. The test results show that the designed antenna, which has the smallest opening at the antenna end, has a better performance than the other Vivaldi antennas tested in respect of the received signal magnitude.
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  • Fumio KIRA, Naoki HONMA, Keizo CHO
    Type: Article
    Session ID: POFT200287
    Published: September 19, 2002
    Released: June 23, 2017
    CONFERENCE PROCEEDINGS FREE ACCESS
    A single reflector multi-beam antenna provides high efficiency beams at more than one direction and it's structure is simple. However, the sidelobe levels of the multi-focal reflector that provide high aperture efficiency are high. Furthermore, to improve the pattern at wide scanning angle is difficult because the design flexibility of the foci arrangement is inadequate. This paper proposes a modified multi-focal parabola reflector design method that provides various feed arrangement. The parameters of this reflector are decided based on geometries of parabola and torus reflector. We demonstrat that this design method can reduce the error between proper feed points and the design and can control the antenn characteristics easily.
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  • Tohru Sunaga, Tadayuki Fukuhara, Song Shi, Masanori Kato, Fangwei Tong ...
    Type: Article
    Session ID: POFT200288
    Published: September 19, 2002
    Released: June 23, 2017
    CONFERENCE PROCEEDINGS FREE ACCESS
    Communication quality deteriorates by the fading due to the multipath and the influence of interference waves from other base stations in mobile telecommunication systems. An adaptive array antenna has been expected as a technology that reduces the influences of these undesired waves. Many researches on adaptive array antenna have been done so far for base stations. In this paper, a 4-element adaptation array antenna evaluation device in mobile terminal was developed to verify the suppression effect on interference by the adaptive array antenna. The change of the arrival direction on the mobile station is faster than that on a base station. It is reported in this paper that the transmitting signal was acquired by this developed device from the commercial CDMA base stations (800MHz band) and with these signals the validity of the adaptive array antenna in mobile terminal was verified.
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  • Fangwei Tong, Masanori Kato, Kazumi Saburi, Shigeru Kimura, Tohru Suna ...
    Type: Article
    Session ID: POFT200289
    Published: September 19, 2002
    Released: June 23, 2017
    CONFERENCE PROCEEDINGS FREE ACCESS
    A local virtual signal tuned (VST) null-steering adaptive antenna array applied to a CDMA mobile station is proposed in this paper. The proposed adaptive array detects the spatial signature of incident signals and generates local uncorrelated virtual signals based on the spatial signature to control the array weights in order to form the required array radiation pattern. The proposed array can control its radiation pattern very flexibly since it is tuned by local virtual signals instead of received signal. Lab and field measurements show that the proposed adaptive array has a better performance than a conventional post-despread architecture adaptive array.
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  • Eddy TAILLEFER, Cyril PLAPOUS, Jun CHENG, Kyoichi IIGUSA, Takashi OHIR ...
    Type: Article
    Session ID: POFT200290
    Published: September 19, 2002
    Released: June 23, 2017
    CONFERENCE PROCEEDINGS FREE ACCESS
    The Electronically Steerable Parasitic Array Radiator (ESPAR) antenna has low cost and low com- plexity relatively to conventional array antennas. Because of the low complexity of the antenna there is only a single-port output for processing the signals impinging on the antenna elements. Since a reactance-domain MUSIC algorithm for ESPAR antennas has be proposed, the practical problem of the estimation of direction of arrivals with an ESPAR antenna can be tackled. In this paper, two experimental methods of estimating the arrival signal angles is proposed. By the way, a method of solving the practical problem of the calibration of the ESPAR antenna output signal model is shown. The experiment results show that for one impinging signal the direction of arrival can be estimated with a precision of 3 degrees.
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  • Yoshiaki AMANO, Takashi INOUE, Hideyuki SHINONAGA
    Type: Article
    Session ID: POFT200291
    Published: September 19, 2002
    Released: June 23, 2017
    CONFERENCE PROCEEDINGS FREE ACCESS
    Focused on eigenvalues of correlation matrices received at array antenna, we proposed a method of angular spread estimation. Based on the method of angular spread estimation, we estimated the angular spread of the received signals at base transceiver a station of smart antenna testbed. As a result, we confirmed that the estimated angular spread agree with the value that is known generally.
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  • Type: Appendix
    Pages App1-
    Published: September 19, 2002
    Released: June 23, 2017
    CONFERENCE PROCEEDINGS FREE ACCESS
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  • Type: Appendix
    Pages App2-
    Published: September 19, 2002
    Released: June 23, 2017
    CONFERENCE PROCEEDINGS FREE ACCESS
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