Mitsugi, Jin



Faculty of Environment and Information Studies (Shonan Fujisawa)



E-mail Address

E-mail address

Related Websites

Career 【 Display / hide

  • 1987.04

    Nippon Telegraph and Telephone Corporation

  • 2004.04

    NTT Communications

  • 2004.04


Academic Background 【 Display / hide

  • 1985

    Nagoya University, Faculty of Engineering, Aerospace Engineering

    Nagoya, University, Graduated

  • 1987

    The University of Tokyo, Graduate School, Division of Engineering, Aerospace Engineering

    Tokyo, Graduate School, Completed, Master's course

Academic Degrees 【 Display / hide

  • Dr.Eng., The University of Tokyo, Dissertation, 1996


Research Areas 【 Display / hide

  • Dynamics/Control (Machine Mechanics/Control)

  • Communication/Network engineering (Communication/Network Engineering)

Research Keywords 【 Display / hide

  • Mechatronics

  • RFID

  • Wireless communications

  • Computational Engineering

Research Themes 【 Display / hide

  • Architecture of networked RFID, 


     View Summary

    System architecture design of network RFID system.

Proposed Theme of Joint Research 【 Display / hide

  • network RFID

    Interested in joint research with industry (including private organizations, etc.),  Desired form: Cooperative Research

  • Wireless Sensor Network

    Interested in joint research with industry (including private organizations, etc.),  Desired form: Cooperative Research


Papers 【 Display / hide

  • A novel method to improve the subcarrier frequency accuracy for UHF RFID sensing system

    Tang K., Zhang C., Wang M., Xu S., Ji S., Yan N., Min H., Mitsugi J.

    2021 15th Annual IEEE International Conference on RFID, RFID 2021 (2021 15th Annual IEEE International Conference on RFID, RFID 2021)   2021.04

    ISSN  9781665440905

     View Summary

    This paper presents a novel method to improve the subcarrier frequency accuracy of tag chip for UHF RFID sensing system based on EPC global Gen2 protocol. By changing the tag's response to the Write command, the tag returns the subcarrier before returning the response specified in the protocol. In this way, a frequency calibration loop will be established between reader and tag. This method not only enables a low-power oscillator with a precise frequency to be integrated into a tag chip, but also enables flexible configuration of the frequency. The tag chip containing this idea is fabricated in SMIC 0.18 μm CMOS process with a die size of 850 μm × 850 μm. Measurement results show that the proposed novel method can realize the calibration of the subcarrier frequency, and the subcarrier frequency deviation is less than ±0.385KHz in the range of 40KHz-640KHz. With this accuracy, the tag can be allocated up to 78 subcarrier communication channels.

  • Wireless modal analysis with backscatter sensors subjected to clock instability

    Mitsugi J., Tanaka H.

    WiSEE 2020 - 8th Annual IEEE International Conference on Wireless for Space and Extreme Environments, Proceedings (WiSEE 2020 - 8th Annual IEEE International Conference on Wireless for Space and Extreme Environments, Proceedings)     17 - 23 2020.10

    ISSN  9781728164519

     View Summary

    This paper examines the practicality of concurrent sensor data streaming with backscatter communication applied to modal analysis, which demands accurate data synchronization among streams. The major synchronization error source in concurrent backscatter streaming system is the instability of backscatter sensor clock. Synchronization of the streams by resampling at receiver is necessary but careless implementation may produce artificial delay caused by the difference of anti-Alias filters tailored to the individual clock rates of backscatter sensors. In this paper, a set of signal processing to synchronize concurrent backscatter signals is designed and implemented in a prototype system. The prototype system comprises backscatter sensors, interrogators and modal analyzer, which takes care of the generation of transfer matrix. The signal processing in the modal analyzer features a recursive least square regression to recover instantaneous sampling rate of backscatter sensor and a zero-phase-filtering in overlap-And-Add approach. The proposal is evaluated by comparing the transfer matrices generated from the prototype system and a commercial modal analysis system where wired accelerometers are used. The experimental results show that the proposed signal processing can successfully synchronize concurrent backscatter streams by eliminating the artificial delay.

  • Simultaneous Gen2 Inventory and Angle of Arrival Measurement of Backscatter Signals with Multiple Commodity SDRs

    Mitsugi J., Kawakita Y.

    2020 IEEE International Conference on RFID, RFID 2020 (2020 IEEE International Conference on RFID, RFID 2020)   2020.09

    ISSN  9781728155760

     View Summary

    Simultaneous inventory and angle of arrival (AoA) measurement of UHF RF tags is strongly demanded for item searching in warehouses and offices. Existing high accuracy AoA measurements of RF tags mainly employ a radio comprised of multiple antennas and coherent receivers to produce synchronized multiple IQ streams. Such radio is usually realized as a dedicated hardware and software, which is not suitable for prototyping new ideas. This paper proposes a method to realize simultaneous inventory and AoA measurement with multiple commodity software defined radios (SDRs). In the proposal, the cancellation of mutual phase offsets, an well known problem of multiple commodity SDRs, is done by physically switching the combination of receiving antennas and receivers with an external RF switch and subtracting the two phase differences. This way, the calibration before AoA measurement can be done during the process of phase measurement with no human intervention. The antenna switching is integrated into a SDR Gen2 interrogator developed on a dual RF-ports USRP. The external RF switch is synchronously controlled with Gen2 inventory progress using Gen2 protocol features called action and target. The accuracy of phase offset cancellation was evaluated with wired and wireless experiments with commercial Gen2 RF tags. The experiments revealed that AoA measurement can be simultaneously performed with Gen2 inventory without any intervention achieving less than 3 degree of phase offset cancellation error.

  • Channel Reservation by Even-odd Separation in Multiple Subcarrier Multiple Access

    Takahashi K., Takazawa Y., Kamei H., Mitsugi J., Ichikawa H., Kawakita Y.

    2019 12th International Conference on Mobile Computing and Ubiquitous Network, ICMU 2019 (2019 12th International Conference on Mobile Computing and Ubiquitous Network, ICMU 2019)   2019.11

    ISSN  9784907626419

     View Summary

    © 2019 IPSJ. Authors propose a method for improving channel reservations in multi-subcarrier multiple-access wireless communications schemes. This scheme is designed for use with wide-area synchronous sensing zones that use functionally extended multi-subcarrier multiple-access subcarrier communication schemes for passive radio-frequency identification (RFID). When the sensing target is larger than the communication distance of the sensor, the sensing zone must be divided. Overlapping zones invariably occur in this case. Sensors in overlapping zones transmit signals to their respective receivers over the same channels and interference follows. If three or more zones are placed side by side, middle zone's communication capacity is lower than else zones. Because, middle zone can not use nearly center frequency. However, the communication capacity and its variations have not been examined for how they are affected by the zones in which overlapping sensors are used. This study investigated communications between sensors in overlapping zones by assigning channels to receivers in odd zones. The channel reservation method and the conventional method were simulated in MATLAB an compared. By allocating channels to sensors in odd zones, communication capacity can be improved and variations suppressed.

  • Statistical carrier phase recovery for narrow-band backscatter wireless link

    Sato Y., Mitsugi J., Kawakita Y., Ichikawa H.

    Proceedings of 2019 25th Asia-Pacific Conference on Communications, APCC 2019 (Proceedings of 2019 25th Asia-Pacific Conference on Communications, APCC 2019)     142 - 147 2019.11

    ISSN  9781728136790

     View Summary

    © 2019 IEEE. This paper proposes a carrier recovery method tailored to narrow-band multicarrier backscatter wireless links, which employ subcarrier modulation. Because backscattered subcarrier is usually produced by low accuracy and low rate internal clock in a low power consumption or batteryless, wireless sensor, the corresponding receiver needs to compensate the subcarrier frequency drift and fluctuation dynamically for demodulation and decoding. Although a backscattered subcarrier is produced by changing the antenna reflection coefficient of wireless sensor, the backscattered signal is usually converted to a zero-crossing signal to enhance signal resolution, and edge detection based demodulator is applied at the receiver. However, in a multicarrier backscatter system, the edges at symbol boundaries of each backscattered subcarrier become indistinct because of the narrow bandwidth. Consequently, subcarrier frequency estimation with existing carrier recovery technique may results in error. This paper solves the problem by removing outliers of temporal subcarrier frequency based on the statistical distribution and applying a feedback control. The statistical carrier recovery method is examined experimentally with a prototype wireless sensor and a software defined receiver to reveal the method can automatically compensate unstable subcarrier with about 10-2 order drift and outperforms the popular frequency doubler based carrier recovery. The optimal feedback gain, 1.0, is also revealed.

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Papers, etc., Registered in KOARA 【 Display / hide

Presentations 【 Display / hide

  • Guest Editorial

    Zhou Meng Chu, Fortino Giancarlo, Shen Weiming, Mitsugi Jin, Jobin James, Bhattacharyya Rahul

    IEEE Transactions on Automation Science and Engineering, 2016.07

  • Improvement in multiple access channel allocation for sensor node configuration based on RFID communication

    Matsuda Tomoaki, Wakisaka Yuuki, Kawakita Yuusuke, Ichiakwa Haruhisa, Mitsugi Jin

    RFID, 2016.01, IEEE

     View Summary

    <p>Wireless sensors are expected to be low cost and to reduce their power consumption so that a large number of sensors can be installed for collecting real-world information. Passive radio-frequency identification (RFID) is proposed to assign communication channels to sensors that only send analog sensing signals for their multiple access control. In this method, the RFID reader-writer assigns channels to all sensors by writing channel numbers to the RFIDs attached to the sensors. We propose a method that more efficiently assigns a multiple access channel to the controlled sensor by using passive RFID. We determine the channel by using the electronic product code (EPC) of the RF tags. This approach results in a large reduction in the number of writes. However, it is shown that there is a tradeoff between the reduction in the number of writes and the total number of channels. In addition, our method has a tradeoff between the reduction in the number of writes and the spectral efficiency.</p>

  • A feasibility study of plug-in type RF tag localization system for handheld UHF RFID reader/writers

    Miyazawa Masato, Igarashi Yuki, Mitsugi Jin

    2015.10, Oral Presentation(general)

     View Summary

    <p>This paper proposes a plug-in type RF tag localization system, using an Angle of Arrival principle, in UHF RFID, particularly targeting handheld reader/writers. Being a plug-in type, the RF tag localization system is receive-only, incurring no radio license requirement, small in size and can be built at low cost. Our fundamental idea is to employ a newly developed short-range mono-pulse method for the RF tag direction detection enabled with affordable software defined radio device and an analog front end. In this paper, we report an experimental evaluation with a functional prototype primarily on the detecting accuracy. It is shown that we can achieve about 3 degree accuracy for RF tags at 7.3 m distance from a 4 W EIRP reader/writer. Because the measurement in the direction of boresight is more stable than the other directions, the direction accuracy can be improved when we feed back the direction detection to the orientation of handheld reader/writer. We also confirm this feature experimentally.</p>

  • Boxcan

    Sato Yuki, Sato Taisuke, Mitsugi Jin

    APCC, 2015.10, Oral Presentation(general), IEICE

     View Summary

    <p>This paper introduces «Boxcan», an information retrieval platform for aggregated objects in ID-based object management system based on GS1 EPCglobal architecture framework. Boxcan platform receives an EPC of a container, then provides a tree structure of current parent-child relationship between the EPCs of the container and its inner objects. This paper proposes the system design of Boxcan platform and its applications. The proposed system design is evaluated with a field test of a practical object management system including Boxcan platform. A technical challenge to realize this function of Boxcan platform, fast retrieval of current parent-child relationship of EPCs from EPCIS, is also discussed in this paper. The effectiveness of the caching mechanism of EPC's current parent-child tree, which is a solution to this technical problem, is also evaluated by an experiment in a comparison with direct querying to EPCIS.</p>

  • Multi-code filtering &amp; collection

    Mizutani Iori, Mitsugi Jin, Endo Fumihiko, Ehara Masaki, Suzuki Hiroyuki

    IEEE RFID-TA 2015, 2015.09, Oral Presentation(general)

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Research Projects of Competitive Funds, etc. 【 Display / hide

  • 同期・多数接続信号処理を可能とするバックスキャッタ通信技術の研究開発


    総務省, 電波資源拡大のための研究開発

  • Plug-in localization system using multiple commercial-off-the-shelf software defined receivers


    MEXT,JSPS, Grant-in-Aid for Scientific Research, 三次 仁, Grant-in-Aid for Scientific Research (B), Principal Investigator

  • バッテリレス・ワイヤレス完全同期ストリーム通信を実現するマルチサブキャリア多元接続方式の高信頼化と広域化


    総務省 , Strategic Information and Communications R&D Promotion Programme (SCOPE), Principal Investigator

  • 電波伝播特徴量を用いたRFID読み取り空間フィルタの実現


    MEXT,JSPS, Grant-in-Aid for Scientific Research, 三次 仁, Grant-in-Aid for Scientific Research (C), Principal Investigator

  • 電波伝搬特徴量を用いたRFID読み取り空間フィルタの実現


    JSPS, Grant-in-Aid for Scientific Research, Principal Investigator

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Awards 【 Display / hide

  • 功労賞

    MITSUGI JIN, 2005, 電子情報通信学会

    Type of Award: Other Awards

  • 優秀講演表彰

    MITSUGI JIN, 1995, 日本機械学会計算工学部門

    Type of Award: Other Awards

  • 第73期(1995) 優秀講演表彰

    三次 仁, 1995, Japan Society for Mechanical Engineers


Courses Taught 【 Display / hide











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Social Activities 【 Display / hide

  • 920MHz帯センター無線システムの周波数共用技術に関する調査研究会

  • 衛星通信技術の普及に関する検討会

  • 超高速衛星の技術力強化のための調査検討会

  • 920MHz電子タグ調査検討会

  • GS1 EPCglobal


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Memberships in Academic Societies 【 Display / hide

  • 電子情報通信学会, 

  • Japan Association of Mechanical Engineers, 


Committee Experiences 【 Display / hide

  • 2021.02

    構成員, 総務省 情報通信審議会衛星通信システム委員会

  • 2019.04

    構成員, 総務省 情報通信審議会陸上無線通信委員会

  • 2017

    Associate Editor, IEEE Journal of RFID

  • 2015

    Associate Editor, IEEE Transactions on Automation Science and Engineering

  • 2015

    Associate Editor, IEEE Internet of Things Journal

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