Hiroyo Ogawa

Klinikum Frankfurt (Oder) GmbH, Frankfort on the Oder, Brandenburg, Germany

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Publications (19)5.83 Total impact

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    ABSTRACT: The Radio on Fiber (RoF) technologies are unique transmission means of radio analog signals through optical fiber cables. These technologies are currently discussed at international standard organizations such as ITU-T, IEC, APT and IEEE802. This invited paper summarizes RoF standardization activities at those standard organizations.
    12/2013
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    ABSTRACT: This paper describes the outline of recent standardization activities for Radio on Fiber (RoF) transmitter by IEC TC103/WG5. RoF transmitter consists of optical fibers, electrical to optical (E/O) converter, and optical to electrical (O/E) converter. IEC TC103/WG5 is working on standardization on measurement method of E/O and O/E devices, and technical specification of RoF transmitter. This paper overviews those standardization activities which are being developed by TC103/WG5 as well as the National Committee of WG5.
    IEICE Transactions on Electronics 02/2013; E96.C(2):138-146. DOI:10.1587/transele.E96.C.138 · 0.39 Impact Factor
  • Chang-Soon Choi, Yozo Shoji, Hiroyo Ogawa
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    ABSTRACT: This paper presents the developed orthogonal frequency division multiplexing (OFDM) baseband processor employing adaptive modulations to grouped subcarriers, and its demonstration in millimeter-wave wireless indoor links. Channel measurements and characterizations are performed in line-of-sight (LOS) office environments where the developed OFDM system is supposed to be used. The OFDM baseband processor utilizes 192 data subcarriers among 256 FFT numbers. To minimize bit-error-rate (BER) performance in frequency selective channels of millimeter-wave wireless indoor links, these 192 data subcarriers are grouped into 24 subcarrier groups and independently modulated according to channel characteristics in each subcarrier group. We demonstrate it incorporating with the developed 70 GHz selfheterodyne transceiver. BER measurements and maximum TCP throughput test are performed in practical millimeterwave indoor environments. The results verify the advantages of the proposed adaptive modulation in OFDM and show better BER performance as well as higher throughput performance than a typical OFDM system1.
    IEEE Transactions on Consumer Electronics 11/2011; 57(4):1541-1549. DOI:10.1109/TCE.2011.6131123 · 1.16 Impact Factor
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    ABSTRACT: This paper presents the activities of a feasibility study for LiNbO<sub>3</sub> Mach-Zehnder modulators and systems. In addition, the structure of IEC standardization, standardization activities of IEICE Japan, and international round-robin test results are described.
    Microwave photonics, 2008. jointly held with the 2008 asia-pacific microwave photonics conference. mwp/apmp 2008. international topical meeting on; 11/2008
  • Chang-Soon Choi, Yozo Shoji, Hiroyo Ogawa
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    ABSTRACT: This paper describes new 60-GHz-band bidirectional fiber-fed wireless access systems, which provide simple antenna base-station architecture and full compatibility with dense wavelength-division multiplexing (DWDM) fiber-optic networks. For downlink millimeter-wave signal generation, the proposed scheme utilizes uplink optical transmitters as downlink optical heterodyne sources, which promises wavelength allocations of downlink and uplink signals that are fully compatible with those of DWDM networks. The frequency instability and poor phase-noise characteristics of these optically heterodyned signals do not affect transmission quality at all by using self-heterodyne wireless transmission techniques. Experimental results demonstrate that the proposed scheme provides not only strong immunity to phase-noise degradation coming from both fiber and millimeter-wave links, but also less sensitivity to fiber transmission loss than conventional remote optical heterodyne approaches. With the help of these attractive features, we successfully demonstrate both downlink and uplink orthogonal frequency-division multiplexing data transmissions in both 10-km fiber-optic and 60-Hz links.
    IEEE Transactions on Microwave Theory and Techniques 02/2008; DOI:10.1109/TMTT.2007.912219 · 2.94 Impact Factor
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    ABSTRACT: A novel cost-effective 60-GHz multi-chip module (MCM) is proposed and demonstrated. It is based on a low-cost multilayer printed wiring board (PWB) with a novel vertical transition and a single layer waveguide transition which enables the use of low-cost substrates with high dielectric loss for millimeter wave applications. The proposed MCM technology has been successfully applied to the packaging of a 60-GHz self-heterodyne mixer, and no substantial difference in the RF performance is observed with the packaging. © 2007 Wiley Periodicals, Inc. Microwave Opt Technol Lett 49: 2303–2305, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.22719
    Microwave and Optical Technology Letters 09/2007; 49(9):2303 - 2305. DOI:10.1002/mop.22719 · 0.62 Impact Factor
  • Yozo Shoji, Chang-Soon Choi, Hiroyo Ogawa
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    ABSTRACT: Millimeter-wave OFDM wireless personal area network system applying adaptive modulation for grouped sub-carriers was newly developed. It is composed of 100 MHz sampling speed OFDM modems which can employ adaptive modulation for every 8 neighbored subcarriers, and 70-GHz band self-heterodyne transceivers equipped with receiver space diversity. The detailed specifications and the expected maximum throughput performance are described. The operational principle of the developed system under selective multipath channel environment is also discussed. The fundamental test results demonstrate the use of developed adaptive modulation for millimeter-wave OFDM WPAN system has the possibility to improve the throughput performance under multipath channel environment
  • Kiyoshi Hamaguchi, Hiroyo Ogawa
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    ABSTRACT: In this paper we describe overview of the test-bed using gigabit millimeter-wave broadband wireless access systems using 32/18/37 GHz bands. Then, specification and performance of a portable customer-premise equipment employing 4-states combination of adaptive modulation and forward error correction at 32 GHz as a part of the test-bed is introduced. Empirically derived formula of the number of rain fade events per year is also derived to assist designing for unavailability at millimeter wave links.
    Proceedings of the 64th IEEE Vehicular Technology Conference, VTC Fall 2006, 25-28 September 2006, Montréal, Québec, Canada; 01/2006
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    ABSTRACT: A fiber-optic broadband signal distribution link based on a millimeter-wave self-heterodyne transmission/optical remote heterodyne detection technique was developed. To avoid having to use expensive optical and millimeter-wave devices to construct a frequency-stable fiber-optic millimeter-signal transmission system, a millimeter-wave self-heterodyne transmission technique was used, in which transmitted signals were generated by an optical remote heterodyne detection scheme. Theoretical discussion and experiments demonstrated that it is possible to construct an inexpensive millimeter-wave signal distribution link without the complexity or difficulties of a conventional link structure because applying the principle of the millimeter-wave self-heterodyne transmission technique enables the use of an unstable millimeter-wave carrier generated by heterodyning of two independently operating lasers. It was experimentally demonstrated that the proposed fiber-optic millimeter-wave link could successfully achieve bit-error-free transmission of a 156-Mb/s QPSK-formatted signal over a 10-km fiber link and a 5-m pseudo-air link.
    IEICE Transactions on Electronics 07/2005; DOI:10.1093/ietele/e88-c.7.1465 · 0.39 Impact Factor
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    ABSTRACT: A new automatic-threshold-control (ATC) system for the amplitude-shift-keying (ASK) transceivers without using automatic gain control (AGC) was developed. When signal-to-noise ratio (SNR) in a transmission system fluctuates, the new system optimizes the threshold by statistic processing. In this paper, the schematic block diagram, the theory of statistical processing, and the performance estimated by numerical simulations are shown. The simulations show that under ideal conditions, the system can control the threshold voltage in a broad SNR region (wider than 20 dB). Delay of response and trapping in real situation can occur, but, the problems can be avoided by waveform shaping. It is thus concluded that the new ATC system can be applied to ASK transceivers.
    IEICE Transactions on Communications 03/2005; 88-B(3):1249-1252. DOI:10.1093/ietcom/e88-b.3.1249 · 0.33 Impact Factor
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  • Yozo Shoji, Kiyoshi Hamaguchi, Hiroyo Ogawa
    The Journal of The Institute of Image Information and Television Engineers 01/2002; 56(8):1334-1341. DOI:10.3169/itej.56.1334
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    ABSTRACT: The design and performance of a millimeter-wave video transmission system using 60-GHz band for indoor broadcasting-satellite (BS) signals transmission is presented. This system can transmit multiple video signals such as broadcasting signals and user-oriented signals to a television set indoors. To minimize the local oscillator's frequency offset and phase-noise effects, the system uses a self-heterodyne scheme. Based on the concept, the system is developed to meet required carrier-to-noise-power- ratio (CNR) and 3rd-order intermodulation (IM). The BS transmission was experimentally done by using the transmitter and receiver setup. The results are very promising and show the feasibility of the system.
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    ABSTRACT: A concept and requirements of a millimeter-wave video transmission system as a wireless home-link using 60-GHz band are described. This system can transmit broadcast television (TV) signals from TV antennas to TV set and thus can be regarded as a substitute for a feeder line. The feasibility study by investigating the system's CNR and SNR performances using MMIC-based experimental setup is also described.
    Microwave Conference, 2000. 30th European; 11/2000
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    ABSTRACT: This paper describe the broad band antennas for a wireless video home-link. 8×8 circular waveguide array antenna with stripline feed are developed. The maximum antenna gain was 22dBi and 3dB bandwidth was 6GHz (10%) at V band.
    Microwave Conference, 2000. 30th European; 11/2000
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    ABSTRACT: This paper reports our first trial hardware of the "millimeter-wave video transmission system"[l][2]. This paper especially focuses on the simplified assembly structure of this trial hardware, which is advantageous for low-cost production and size reduction.
    Microwave Conference, 2000. 30th European; 11/2000
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    ABSTRACT: This paper investigates video signal degradation factors caused by intermodulation products from mixers or other non-linear devices of the video transmission system for wireless home-links, which transmits communications satellite (CS), broadcasting satellite (BS), and terrestrial broadcasting in the VHF band video signals. The second-and third-order intercept points for the non-linear devices are calculated from the view of the desired to undesired signal power ratio (DUR) of each video signal.
    Microwave Conference, 2000. 30th European; 11/2000
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    Kiyoshi Hamaguchi, Hiroyo Ogawa
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    ABSTRACT: Fixed wireless access systems (FWAs) are expected to become the choice as a complementary way to the wired lines for broadband access in telecommunications. In order to show the effectiveness on the broadband FWAs in meaning of development on applications as well as characterizing the quality of the wireless link, we have developed a test-bed for the broadband FWA system. This paper presents an overview of a developed gigabit millimeter-wave broadband FWA system test-bed, which is able to handle up to 1 Gbps order data rate over wide-area such as Yokosuka urban and YRP areas in Japan. The test-bed enables experimental study on both network application and data transmission characteristics on the high data-rate FWA. Current experimental studies on the test-bed are also described.
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    Kiyoshi Hamaguchi, Yozo Shoji, Hiroyo Ogawa
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    ABSTRACT: Wideband communications are required for various applications such as high-speed wireless local-area-networks (W-LANs), wireless personal-area-networks (W-PANs) and video transmissions. 60 GHz band is one of possible frequencies for such wider frequency requiring systems. Within this band, various kinds of wireless data transmissions are expected to develop without license. In this paper we introduce both an Ad hoc wireless access and a vertically-connected wireless link systems we developed, and propose a network architecture by using both millimeter-wave systems, which enables both video and data signal transmissions through broadband wireless connections. Concept, overview and the developed system specifications for a broadcasting signal transmission as well as data transmission are presented.