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[Author] Yoichi NAKAGAWA(2hit)

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  • Advanced Millimeter-Wave Radar System to Detect Pedestrians and Vehicles by Using Coded Pulse Compression and Adaptive Array

    Takaaki KISHIGAMI  Tadashi MORITA  Hirohito MUKAI  Maiko OTANI  Yoichi NAKAGAWA  

     
    PAPER-Sensing

      Vol:
    E96-B No:9
      Page(s):
    2313-2322

    This paper reports an advanced millimeter-wave radar system to enable detection of vehicles and pedestrians in wide areas around the radar site such as an intersection. We focus on a pulse coding scheme using complementary codes to reduce range sidelobe for discriminating vehicles from pedestrians with high accuracy. In order to suppress sidelobe increase created by RF circuit imperfections, a π/2 shift pulse modulation method with a complementary code pair cycle is presented. Moreover, in order to improve the angular resolution, a high-resolution direction of arrival estimation involving Tx beam scanning is presented. Experiments on a prototype confirm its range sidelobe suppression exceeds 40dB and its angular resolution is 5° for two human's separation at the distance of about 10m in an anechoic chamber. In a trial intersection experiment, a pedestrian detection rate of 95% was achieved at the false alarm rate of 10% in the range from 5m to 40m. The results prove the system's feasibility for future automotive safety application.

  • Evolution of Millimeter-Wave Multi-Antenna Systems in the IoT Era Open Access

    Kazuaki TAKAHASHI  Hidekuni YOMO  Takashi MATSUOKA  Junji SATO  Yoichi NAKAGAWA  Makoto YASUGI  Masataka IRIE  Naganori SHIRAKATA  Koji TAKINAMI  

     
    INVITED PAPER

      Vol:
    E100-C No:10
      Page(s):
    809-817

    In this paper, we present the roles played by millimeter-waves in the realization of an Internet of Things (IoT) society. Millimeter-waves are becoming essential frequency resources, enabling ultra-high-speed wireless networks supporting massive data traffic and high-resolution sensor devices. Multiple antenna technologies such as phased arrays, sector antennas, and MIMO signal processing are key technologies for putting these into practical use. In this paper, various examples of integration of multi-antenna systems are shown, as well as demonstration on 60GHz-band millimeter-wave wireless access and 79GHz-band high-resolution radar. We also propose applications to ITS for an IoT society, combining millimeter-wave wireless access and radar sensors, and discuss technical issues to be solved in the future.