Advanced Wireless & Communication
Research Center

Message from the Director, Prof. Takeo Fujii
The Convid-19 disaster is slightly improved in 2022; faculties and students of Advanced WirelessCommunication Research Center (AWCC) return to the office and the ratio of face-to-face meeting
dramatically inreases. In our research communities, face-to-face international conferences anddomestic workshops are returned. The activities of international conference presented bymembers of AWCC were dramatically increased comared with statistics during the period ofcorona. The activity publishing journal papers also keep high level in 2022. We also tackle several
national projects including beyond 5G, low power sensor networks and cooperative autonomousvehicles in 2022.
For the years, AWCC has been aiming and conducting four missions that are;- Dedication to advanced research on wireless communications; offering more unique results.
- Education in graduate school for cultivating specialty in engineering; specialized and universal
education in the area.
- Active collaboration / joint research with industries and government; transferring the outcomesto the society.
- Constant acquisition of competitive research funds; for self-supported operation.
The current vision of AWCC is “Ambient Wireless in Connected Community (AWCC).” AWCC
intends to cover broader research area including not only wireless communications but also any
promising aspects of “wireless” and “communications”. As an academic institute, it is our mission
to pursue basic research in science and technology. Toward the goals, AWCC will enhance its
force and strengthen its presence in the world.
We are focusing the following four research sectors.
(1) Wireless Technology as Social Infrastructure
Wireless technologies will have more importance in the society as the base of safe, secure andsmart life for the individual and the community. Intelligent Transport System (ITS) is one of the
focused topics, anticipating the great demand for automated driving.
(2) Innovative Hardware for Wireless & Communication
Demands for broadband and high-capacity mobile communication systems are very strong,
and 5G and beyond system is being developed in the world. The 5G and beyond system introduces
new usage of frequency spectra called multi-band multi-access, which requires innovation in RF
hardware to achieve higher-accuracy signal transmission with flexibility. Also, wireless powertransfer is another hot and important topic.
(3) Advanced Wireless System & Networks
We have developed many fundamental technologies such as distributed dynamic multi-hop
network, cognitive radio, fault-tolerant network operation, and radio environment-aware
communications. From now on, we integrate the technologies and establish an ultimate wirelessnetwork design.
(4) Exploring Low Power Wireless
By reducing power consumption of wireless system dramatically, applications of wirelesscommunications will spread wider than now. It will make all things connected in the world,
realizing the word "IoT". Innovative low-power technologies are necessary to realize such a world.
As the open research center to the society, AWCC would like to think together with people
and contribute much in research and education of “wireless” and “communications”. We hopeyour kind help and great understanding to AWCC.

-1-１. ABOUT AWCC
1.1 OVERVIEWThe Advanced Wireless Communication
Research Center (AWCC) was launched in
April 2005 with the aims of establishing a
global hub for wireless communications;advancing education in wireless technology;
industrial

collaboration

andtechnology

transfer; and nurturing young engineers
with strong emphasis on both theoreticalandexperimental

aspectsofwireless

communications. In April 2015, the center was re-launched as the Advanced Wireless andCommunication Research Center with the same abbreviation, AWCC, to enhance its remarkablerange of activities over the previous ten years. With funding of approximately 1000 million yen
over nine years, the center consists of 4 full time, 5 concurrent, 20 cooperative, and 6 visiting
professors. In addition, there are 9 visiting professors from industry and more than 100 graduate
students, post-doctoral and research fellows. The center actively contributes to academic societiesand publishes more than 150 papers annually in top journals and proceedings of international
conferences.
The AWCC organizes regular seminars and workshops with the highlight of 2014 being the“Tokyo Wireless Technology Summit” held in March 2014. The meeting focused on the next major
phase of mobile telecommunications called 5th generation (5G) and attracted approximately 240
participants from all over the world.

1.2 FACILITIESAWCC is located on the east-campus of the University ofElectro-Communications in Chofu city, Tokyo near Shinjuku
district in Japan. The center has opened with 10,441 square footof modern research space containing a class room, twoconference rooms, four research offices, and two experimentrooms with a wide range of instruments including FPGA
development platforms, signal generators, vector network
analyzers, spectrum analyzers, software defined radios, and soon. Also, it has extensive computer and network resources
including high-speed workstations and personal computerswhich are integrated with resources of the Univeristy of ElectroCommunications.

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1.3 PEOPLE【Director, Full-time Prof. Takeo Fujii】
Takeo Fujii was born in Tokyo, Japan, in 1974. He received the B.E., M.E.
and Ph.D. degrees in electrical engineering from Keio University,
Yokohama, Japan, in 1997, 1999 and 2002 respectively. From 2000 to 2002,
he was a research associate in the Department of Information andComputer Science, Keio University. From 2002 to 2006, he was an
assistant professor in the Department of Electrical and Electronic
Engineering, Tokyo University of Agriculture and Technology. From 2006
to 2014, he has been an associate professor in Advanced WirelessCommunication Research Center, The University of Electro-Communications. Currently, he is a
professor in Advanced Wireless and Communication Research Center, The University of ElectroCommunications. His current research interests are in cognitive radio and ad-hoc wirelessnetworks. He received Best Paper Award in IEEE VTC 1999-Fall, 2001 Active Research Awardin Radio Communication Systems from IEICE technical committee of RCS, 2001 Ericsson Young
Scientist Award, Young Researcher's Award from the IEICE in 2004, The Young Researcher
Study Encouragement Award from IEICE technical committee of AN in 2009, Best Paper Award
in IEEE CCNC 2013, and IEICE Communication Society Best Paper Award in 2016. He is amember of IEEE and a fellow of IEICE.

【Full-time Prof. Koji Ishibashi】
Koji Ishibashi received the B.E. and M.E. degrees in engineering fromThe University of Electro-Communications, Tokyo, Japan, in 2002 and2004, respectively, and the Ph.D. degree in engineering from Yokohama
National University, Yokohama, Japan, in 2007. From 2007 to 2012, he
was an Assistant Professor at the Department of Electrical and Electronic
Engineering, Shizuoka University, Hamamatsu, Japan. Since April 2012,he has been with the Advanced Wireless Communication Research Center(AWCC), The University of Electro-Communications, Tokyo, Japan where
he is currently an Associate Professor. From 2010 to 2012, he was a Visiting Scholar at the Schoolof Engineering and Applied Sciences, Harvard University, Cambridge, MA. Prof. Ishibashi has
contributed more than 100 articles to international journals and conference proceedings. His
current research interests are grant-free access, non-orthogonal multiple access (NOMA),
millimeter wave communications, ultra-low power communications, signal processing, andinformation theory. He is a senior member of IEEE and IEICE.

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【Full-time Associate Prof. Koichi Adachi】
Koichi Adachi received the B.E., M.E., and Ph.D. degrees in engineeringfrom Keio University, Japan, in 2005, 2007, and 2009 respectively. His
research interests include cooperative communications and energy
efficient communication technologies. From 2007 to 2010, he was a Japan
Society for the Promotion of Science (JSPS) research fellow. He was thevisiting researcher at City University of Hong Kong in April 2009 and thevisiting research fellow at University of Kent from June to Aug 2009. FromMay 2010 to May 2016, he was with the Institute for Infocomm Research,
A*STAR, in Singapore. Currently, he is an associate professor at The
University of Electro-Communications, Japan. He was an Associate Editor IEEE WirelessCommun. Lett. between 2016 – 2022, IEEE Trans. Veh. Technol. between 2016 – 2018, IEEE
Trans. on Green Commun. and Net. between 2016 – 2022, IEEE Open J. of Veh. Technol. since2019. He is a senior member of IEEE and a member IEICE. He was recognized as the Exemplary
Reviewer from IEEE Wireless Commun. Lett. in 2012, 2013, 2014, and 2015. He is a coauthor of
WPMC2020 Best Student Paper Award.

【Full-time Associate Prof. Kun Li】(Joined on 1st Apr. 2023)
Kun Li received the B.E. degree in communication engineering from the
Nanjing University of Posts and Telecommunications, Nanjing, China, in
2011, and the M.E. and Ph.D. degrees in electrical engineering from the
University of Toyama, Toyama, Japan, in 2014 and 2017, respectively.
From 2017 to 2019, he was a Researcher with the Electromagnetic
Compatibility Laboratory, National Institute of Information andCommunications Technology, Tokyo, Japan. From 2020 to 2023, he wasan Assistant Professor with the Faculty of Engineering and Design,
Kagawa University, Takamatsu, Japan. He was a Visiting Researcher with the CNRS/IETR,
University of Rennes 1, Rennes, France, from 2022 to 2023. In 2023, he joined the Advanced
Wireless and Communication Research Center, The University of Electro-Communications,Tokyo, Japan, where he is currently working as an Associate Professor. His research interests
include electromagnetic computation and measurement for radiation safety by human exposure
to electromagnetic fields in radio frequencies, antenna design and measurement techniques for
wireless body area network system. Dr. Li was the recipient of the Young Scientist Award of the
URSI, in 2020, the Risaburo Sato Award of EMC Sapporo & AMPEC, in 2019, the IEEE AP-S
Japan Student Award in 2015, and the IEICE Best Letter Award in 2017. He is a member ofIEEE International Committee on Electromagnetic Safety TC95 and Co-Chair of Working Group
7 under Subcommittee 6 EMF Dosimetry Modeling established to study average schemes andassessment methods of absorbed power density. He is a senior member of URSI and a memberof IEEE and IEICE.
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【Concurrent Prof. Koichiro Ishibashi】
Koichiro Ishibashi has been a professor of The University of ElectroCommunications, Tokyo, Japan since 2011. He received PH. D degreefrom Tokyo Institute of Technology in 1985. He joined Central ResearchLaboratory, Hitachi Ltd. in 1985, where he had investigated low power
technologies for Super H microprocessors and high density SRAMs.
From 2004 to 2011, he was in Renesas Electronics where he developed
low power IPs mainly for mobile phone SOCs as a department manager.
He has presented more than 110 academic papers at international conferences including
ISSCC, IEDM invited papers, and IEEE Journals. He was awarded R&D 100 for thedevelopment of SH4 Series Microprocessor in 1999. He is a member of IEICE and a Fellow ofIEEE.
His current interests include design technology of low power LSI, and IoT applications using
the low power LSIs. They include low power design technology using SOI devices and energy
harvesting sensor networks.

【Concurrent Prof. Koji Wada】
Koji Wada received the B.E. and M.E. degrees from Kinki University,
Osaka, Japan, in 1991 and 1995, respectively, and the Doctorate degreefrom Yamaguchi University, Yamaguchi, Japan, in 1999. From 1999 to
2004, he was a Research Associate with the Department of ElectricalEngineering and Electronics, Aoyama Gakuin University, Kanagawa,Japan. From 2004 to 2015, he worked as an Associate Professor at the
Department of Electronic Engineering, the University of ElectroCommunications, Tokyo, Japan and he is Currently a Professor at the
Department of Computer and Network engineering, Graduate School ofInformatics and Engineering, the University of Electro-Communications. His research interests
include resonators, filters, multiplexers, multiband circuits, tunable circuits, periodic structure,and metamaterial circuits. Dr. Wada is a member of the Institute of Electronics, Information
and Communication Engineers (IEICE), Japan, Institute of Electrical Engineers of Japan(IEEJ), and Japan Institute of Electronics Packaging (JIEP).

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【Concurrent Prof. Motoharu Matsuura】
Motoharu Matsuura received the Ph.D. degree in electrical engineeringfrom the University of Electro-Communications, Tokyo, Japan, in 2004.
In 2007, he joined the Department of Information and Communication
Engineering at the University of Electro-Communications as an AssistantProfessor. From 2010 to 2011, on leave from the university, he joined the
COBRA Research Institute, Eindhoven University of Technology,
Eindhoven, The Netherlands, as a Visiting Researcher, where he studied
ultrahigh-speed optical signal processing using semiconductor-based
devices. He is currently a Professor with the Graduate School of Informatics and Engineering,
Department of Communication Engineering and Informatics, University of ElectroCommunications. His research interests include optical signal processing, photonic subsystems,
and radio-over-fiber transmission systems. He is the author or coauthor of more than 180 papers
published in international refereed journals and conferences. He received the Ericsson Young
Scientist Award in 2008, the FUNAI Information Technology Award for Young Researcher in
2009, and the Telecommunication System Technology Award of the Telecommunications
Advancement Foundation in 2011. He is a member of IEEE, OSA, and IEICE.

【Concurrent Prof. Ryo Ishikawa】
Ryo Ishikawa received the B.E., M.E., and D.E. degrees in electronicengineering from Tohoku University, Sendai, Japan, in 1996, 1998, and2001, respectively. In 2001, he joined the Research Institute of ElectricalCommunication, Tohoku University, Sendai, Japan. In 2003, he joined the
University of Electro-Communications, Tokyo, Japan. His researchinterest is the development of microwave compound semiconductor
devices and related techniques. He was the recipient of the 1999 Young
Scientist Award for the Presentation of an Excellent Paper of the Tohoku
Chapter, Japan Society of Applied Physics.

【Concurrent Prof. Celimuge Wu】
Celimuge Wu received his PhD degree from The University of ElectroCommunications, Japan, where he is currently a professor. His
research interests include Vehicular Networks, Edge Computing, IoT,Intelligent Transport Systems, and AI for Wireless Networking andComputing. He serves as an associate editor of IEEE Transactions on
Network Science and Engineering, IEEE Transactions on Green
Communications and Networking, and IEEE Open Journal of theComputer Society. He is the Vice Chair (Asia Pacific) of IEEE ComSoC
Technical Committee on Big Data (TCBD), and the chair of IEEE TCGCC Special Interest Group-6-

on Green Internet of Vehicles. He is a recipient of 2021 IEEE Communications Society
Outstanding Paper Award, 2021 IEEE Internet of Things Journal Best Paper Award, IEEE
Computer Society 2020 Best Paper Award and IEEE Computer Society 2019 Best Paper Award
Runner-Up. He is a senior member of IEEE.

【Concurrent Associate Prof. Katsuya Suto】
Katsuya Suto received the B.Sc. degree in computer engineering from Iwate
University, Morioka, Japan, in 2011, and the M.Sc. and Ph.D. degrees in
information science from Tohoku University, Sendai, Japan, in 2013 and2016, respectively. He has worked as a Postdoctoral Fellow for Research
Abroad, Japan Society for the Promotion of Science, in the Broadband
Communications Research Lab., University of Waterloo, ON, Canada, from2016 to 2018. He is an Associate Professor with the Graduate School ofInformatics and Engineering, the University of Electro-Communications, Tokyo, Japan. His
research interests include semantic communications, radio propagation, deep learning, andgraph representation. He received the Best Paper Award at the IEEE VTC2013-spring, theIEEE/CIC ICCC2015, the IEEE ICC2016, and the IEEE Transactions on Computers in 2018. He
is currently the Associate Editor of the International Journal of Computers and Applications. He
is a member of IEEE and IEICE.

【Visiting Professors】
Prof. Yasushi Yamao, Ph.D.
Prof. Kazuhiko Honjo, Ph.D.
Prof. Yoichiro Takayama, Ph.D.
Prof. Akira Saito, Ph.D.
Prof. Masashi Hayakawa, Ph.D.
Prof. Hiroshi Suzuki, Ph.D.
Prof. Mitsuo Makimoto, Ph.D.
Prof. Giuseppe T. F. de Abreu, Ph.D.
Prof. Nobuo Nakajima, Ph.D.
Prof. Yukitsuna Furuya
Prof. Takayuki Inaba, Ph.D.
Prof. Tadashi Matsumoto, Ph.D.
【Cooperative Professors】
Prof. Haruhisa Ichikawa, Ph.D.

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Prof. Naoto Kishi, Ph.D.
Prof. Tetsuro Kirimoto, Ph.D.
Prof. Kazuo Sakiyama, Ph.D.
Prof. Fengchao Xiao, Ph.D.
Prof. Xi Zhang, Ph.D.
Prof. Cong-Kha Pham, Ph.D.
Associate Prof. Manabu Akita, Ph.D.
Associate Prof. Yoshiaki Ando, Ph.D.
Associate Prof. Toshiharu Kojima, Ph.D.
Associate Prof. Hisa-Aki Tanaka, Ph.D.
Associate Prof. Kazuki Nishi, Ph.D.
Associate Prof. Satoshi Ono, Ph.D.
Associate Prof. Suhua Tang, Ph.D.
Associate Prof. Hayato Yamaki, Ph.D.
Associate Prof. Zhi Liu【Visiting Professors from Industry】
Prof. Kunio Uchiyama (AIST)
Prof. Takahiro Asai (NTT Docomo)
Prof. Yoji Kishi (KDDI Research Inc.)
Prof. Terunao Soneoka (NTT-AT)
Prof. Akinori Taira (Mitsubishi Research Institute Inc.)
Prof. Hiroyuki Tsuji (NICT)
Prof. Hideki Hayashi (Softbank Corp.)
Prof. Hiroyuki Seki (Fujitsu Laboratory Ltd.)
Prof. Kenji Yoshida (Intermedia Laboratory Inc.)-8-

2.1 Division of Wireless Technologies as Social Infrastructure
2.1.1 Purpose of Research
Wireless technologies will have more importance in the society as the base of safe,
secure and smart life for individuals and community. Various types of machine tomachine communication such as sensors, IoT devices and vehicular communications will
spread in the society taking little notice but support safety and secureness of society, as
well as creating more comfortable and smarter life. In these days, done communications
are also focused on new infrastructures such as flying car, logistics and flying basestations and communications supporting drone is one of the important issues. In thisdivision, technologies for realizing reliable and high capacity communication forsupporting social infrastructure are developed.

2.1.2 Research Staffs and Their Specialties
Prof. Takeo Fujii (Division Leader, ITS, Radio Environment Recognition, Wireless
Security)Prof. Koji Ishibashi (Wireless Security)
Associate Prof. Koichi Adachi (Drone)
Associate Prof. Katsuya Suto (ITS)

2.1.3 Major Research Outcomes in 2022
[Observation Data and 3D Map-based Radio Environmental Recognition] (Fujii Lab.)In Beyond 5G / 6G, which is being researched and developed as the next-generation mobile
communication system, non-terrestrial networks (NTNs) are attracting attention. At NTNs,
drones are expected to be used for a variety of purposes. For efficient drone wirelesscommunication, it requires the estimation of the radio environment in the 3-dimensional
space where drones fly. Although radio propagation models based on empirical rules havebeen traditionally used for radio environment estimation, has a problem that they do notconsider information on surrounding structures and terrain. Recently, 3D maps have beenused as location information. 3D maps have structure and terrain information. In this study,
we propose a method for estimating the received power in the direction of altitude bycombining 3D map information with observations obtained from actual drone flights. theproposed method estimates received power from observed value and diffraction loss which is
calculated by using the 3D map and location information. Fig. 2.1-1 shows the system modelof this study.
From the result of the measurement campaign for the LTE base stations, we conducted inFeb. 2023, the proposed method reduces the RMSE (Root Mean Squared Error) between
estimated values and observed values up to 3.23[dB] from the conventional method whichuses the empirical model. Table 2.1-1 shows the RMSE average of the proposed method andconventional method for each PCI (Physical Cell ID) when observed data are obtained
randomly.
Table 2.1-1 Average RMSE of each method.
PCI 113
Conventional (Ext. Hata)
9.60
PCI 145
Conventional (Ext. Hata)
7.23
Fig. 2.1-1 System model.

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Proposed
6.37
Proposed
4.68

[Realtime Channel Congestion Estimation from Communication Log] (Fujii Lab.)
Even if the received signal power is large, sometimes the throughput of LTE and 5G isdegraded due to channel congestion of other users. In particular, we can understand thissituation at the train station during rush hour and the data rate of a smart phone degrades.
The throughput degradation is usually caused by the channel congestion at the base station
connected by large number of users. A radio environment map generated by statistical valueof each location can predict the average received power of the wireless signal from the basestation but the channel congestion cannot be statistically obtained because of various user
distribution. Therefore, real time channel congestion estimation is required.
In this research we estimate the channel congestion from the communication log at theterminal like smart phone, mobile router in the recent period. Here, we focus on the RSRQ
(Reference Signal Received Quality) value, which is obtained by the ratio of RSRP (Reference
Signal Received Power) to RSSI (Received Signal Strength Indicator). Usually, RSRP canremove the effect interference power but RSSI includes the influence of interference. So that
the RSRQ degrades if the channel congestion occurs. Thee possibility of the estimation ofcongestion from RSRQ is measured at near the rail road of commuter train as shown in Fig.
2.1-2. We show the experimental results in Fig.2.1-3, in which, the relation between
throughput and RSRQ of LTE system is shown. We can understand that the higher RSRQ
has good throughput performance and the lower RSRQ has low throughput performance.
From these results, we can confirm the possibility of the channel congestion estimation fromRSRQ on LTE system.

Fig.2.1-2 Measurement environment.

Fig.2.1-3 Relation between throughput and
RSRQ on LTE system.

【Cyber-Physical Integrated Emulator for Cooperative Automated Driving】(Suto Lab.)

Cooperative automated driving using vehicle-to-everything (V2X) communications is apromising solution for future transportation systems because it can improve the safety ofdriving by cooperative perception, i.e., collection of surrounding information that cannot be
obtained by self-equipped sensors. However, the performance and accuracy of cooperative
perception are affected by the quality of service (QoS) of V2X communications. Toward thepromising transportation system, we developed a network emulator that accurately
evaluates QoS using physical information collected from the real world. Specifically, ourdeveloped emulator has the following features:
1. Multi-modal traffic simulator is integrated into the network simulator to analyze theinterdependency between vehicle mobility and V2X QoS.
2. Actual measurement data in the real world is incorporated to emulate site-specificwireless environments.
3. Any applications using V2X communications can be developed in the platform toemulator cooperative automated driving services, i.e., behavior arbitration, speed
advisory, etc.

- 10 -

Fig. 2.1-4 shows the overview of the developed emulator in which we employ simulation ofurban mobility (SUMO) and NS3 as traffic and network simulators, respectively. The
emulator can evaluate site-specific wireless environments using actual measured signals. For
instance, we can evaluate a spatial-fading effect and consider the handover situation ofmobile terminals, thereby improving the accuracy of QoS evaluation.
Evaluated QoS in cyber space

Traffic
Simulator

OSM• Evaluate QoS considering site-specific
SUMO
Core

wireless environment and traffic

Traffic
simulation• Evaluate reliability of automated driving
apps.

Simulator Integration Interface
Share location of mobiles
Network Simulator

Wireless
InSite

CAM/
DENM
NW
simulation

LTE・5G
HelperNS-3
Core

Automated
Driving app.

Simulate radio
propag atio n inunmeasured area
Application
simulation

WLAN
Helper
Simulate site-specific wireles s environments
Physical Information Interface

PhysicalInformation

Examples of measurement data

Radio
Environment DB

12Traffic

Time series location of each mobile

Wireless

Signal data of each transmitter

Fig. 2.1-4 Overview of cyber-physical integrated emulator.
【3D Radio Map Construction for Drone Networks】(Suto Lab.)

Recently, mobile communication systems have been used for drone services, e.g., video
transmission, remote control, etc. However, non-terrestrial radio propagation, i.e.,
communication between a base station and drone, has yet to be well studied. To address thechallenge, we developed a drone-based sensing system and measured non-terrestrial radio
propagation at our university. Fig. 2.1-5 shows the measured radio map. We can see that thesignal strength drastically changed due to the building, i.e., shadowing. Future more, we canfind that the spatial correlation of the x-axis direction is higher than that of the z-axis
direction. Fig. 2.1-6 demonstrates the interpolation accuracy of ordinary Kriging. We can seethat ordinary Kriging can achieve enough estimation accuracy even with the use of 5%
measured grids (4 measured grids) and gain the estimation accuracy with the increase ofmeasured grids.

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7.5
72120 MHz

6.5

865 MHz6
RMSE [dB]

5.5
5

4.5
4
3.5
3
2.5
2
0

Fig. 2.1-5 Measured radio map.

4

8

12
16
20
24
Number of measured grids

28

32

Fig. 2.1-6 Interpolation accuracy.

[Secure Precoded OFDM Transmission for Next-Gen. IoT Systems] (Koji Ishibashi Lab.)To protect private information in next-generation IoT systems, physical layer security(PLS) is a promising option. This academic year, we considered a single-input, single-output
wiretap channel model comprising a legitimate transmitter (Tx), a legitimate receiver (Rx),and an eavesdropper (Eve) in downlink transmissions with orthogonal frequency divisionmultiplexing (OFDM) and proposed the secure symbol-wise precoding using a random
unitary matrix with the virtual carrier frequency offset (CFO). Rx can easily equalize thereceived signals using priori knowledge of the CFO and achieve a lower error rate
performance than conventional approach by enjoying the frequency diversity. Meanwhile,
Eve has to estimate the virtual CFO besides to the transmitted data from one OFDM symbol,
and this makes the Eve's estimation problem underdetermined. Fig.2.1-7 and Fig.2.1-8
quantitatively confirm that our proposed PLS scheme is more secure than conventional
approaches in terms of bit error rate (BER) and achieves the positive secrecy capacity (SC)even assuming the Eve's precise knowledge about the virtual CFO.

Fig2.1-7 SNR vs. BER comparisons.

Fig 2.1-8 Achievable CDFs of SC considering
maximum estimation error at Eve (𝜔0 ).

2.1.4 Funds【Grants-in-Aid for Scientific Research】- 12 -

1. Scientific Research C “Research on Energy Efficient Wireless Communications Network
Using UAV-BS”
Koichi Adachi【Commissioned Research】

1. METI Project on Research, Development, Demonstration and Deployment (RDD&D) of
Autonomous Driving toward the Level 4 and its Enhanced Mobility Services (RoAD to
the L4), “Harmonization and interoperability of V2V and V2P for deployment of L4 inmixed traffic environment”
Takeo Fujii, Katsuya Suto
2. JST EIG CONCERT Japan " Organically Resilient and Secure Wireless Networks for
Next-Generation IoT Technologies (ORACLE)"
Koji Ishibashi
3. NICT B5G “Technologies for Next Generation Five Dimensional Mobile
Infrastructures”
Takeo Fujii, Katsuya Suto, Koya Sato
【Cooperative Research】

1. TIS Inc., Takeo Fujii, Katsuya Suto
2. NEC Corp. Takeo Fujii- 13 -

2.2

Advanced Hardware Research Division

2.2.1 Purpose of Research
Research and development of wireless information/power transmission hardware
for next generation mobile communication base stations and terminal devices

2.2.2 Research Staffs and Their Specialties
Prof. Koichiro Ishibashi
Low Power RF Devices, Sensor Networks
Prof. M. Matsuura
Wideband RoF Systems, Devices, Fibers and Integration
Prof. R. Ishikawa
Microwave/Millimeterwave Devices and Circuits
Prof. K.Wada
Microwave Filters and Their Applications
Visiting Prof.Y. Yamao
Reconfigurable RF Circuit, Nonlinear Compensation
Visiting Prof. K. Honjo
Microwave Engineering, Semiconductor Devices
Visiting Prof. Y. Takayama Microwave Power Amplifier Systems
Visiting Prof. A. Saitou
Electro-Magnetic Wave Engineering, Antennas

2.2.3 Major Research Outcomes in 2022
（A） [Quasi-millimeter-wave wide -dynamic-range GaN HEMT outphasing amplifier ]（ IshikawaLab.）
In recent years, the greater sophistication and diversity in wireless communication systems have become
remarkable, hence further improvements in performance of wireless transmitters in the base stations are
required. Power amplifiers are an important devi ce, which greatly affect distortions for signals and power
consumption. A peak-to-average power ratio (PAPR) of recent digital wireless signals is large as more than
6 dB. A PAPR of 9 dB is often considered in 4G and 5G OFDM (Orthogonal Frequency Division
Multiplexing) / QAM (Quadrature Amplitude Modulation) systems. In such systems, power efficiency atlarge output power back off levels dominates a total power consumption of the amplifiers than that insaturation levels. Thus, high efficiency characteristics are required for wide dynamic range in the amplifiers,
where a special attention should be paid on the efficiency at large output back-off (OBO) power level.
For this issue, we have developed a quasi-millimeter wave outphasing power amplifier constructing with
two simple 50 -ohm power amplifiers. For the power amplifier design to improve efficiency in the quasimillimeter wave region, a trade -off between a devised circuit configuration and circuit insertion loss
becomes a serious issue. The matching circ uit of the 50 -ohm power amplifiers for consisting to theoutphasing power amplifier has to be carefully designed so that high efficiency is achieved with a low
output power for a high input power, though the circuit is simple forloss reducing. For the fab ricatedoutphasing amplifier with the GaN HEMT MMIC amplifiers designed at 28 GHz band, the dynamic range
was maintained in the bandwidth of about 800 MHz, though there was room for improvement by thematching adjustment for the dynamic range (Fig. 2.2.1).

Fig. 2.2.1 Fabricated GaN HEMT outphasing power amplifier, and its characteristics- 14 -

（B）[OAM Long-Range Communication by Changing Paraboloid Curvature and Feed Position](Ishikawa Lab.)We have demonstrated that the electro-magnetic wave propagation occurs with a single orbital angularmomentum (OAM) mode when a current distribution of the azimuth angle -direction for a circular loop
antenna conductor contains only one Fourier expansion coefficient. This condition almost retains at theloop-antenna conductor length of nλ (n is the integer). As a common issue for the OAM communication,
the directivity of the OAM waves is wide, especially for the loop antenna that has a small antenna aperture.
Therefore, for a long-range communication, paraboloid reflectors are utilized for focusing the OAM waves.
Here, we have tried to optimize the curvature of the concave reflector so that the beam waist position ofeach mode of OAM waves becomes the same. In addition, a position relation among the feed points of theloop antennas was also optimized to improve a signal-to-interference ratio (SIR), based on the interference
cancellation technique.
A 4-channel OAM multiplexing long-range communication test using loop antennas in the 12 GHz band
was carried out. As a result, the worst-values of signal wave and SIR were improved by 6.5 dB and 9.9 dB,
respectively, at 12.2 GHz and 70 cm long distance communication (Fig. 2.2.2).

Fig. 2.2.2 Fabricated roop antenna systems, and its characteristics（C）All-Optical Logic Gate in Semiconductor Optical Amplifiers (Matsuura Lab.)In future data signal processing, it is important to realize integrated technologies that use
the features of optical and electrical devices more efficiently. Logic gate is one of the essentialfunctions, and there is a need for technology that can perform faster processing, as the speedof data processing increases. In the concept of photonic accelerator, more efficient data signal
processing can be achieved by making full use of all-optical signal processing for logic gatesthat require high-speed processing and by using electrical signal processing to control
multiple logic circuits.
Semiconductor optical amplifiers (SOAs), are key devices for all-optical signal processing
and have many advantages such as small-foot print, low switching energy, and availabilityof monolithic integration, compared with other nonlinear devices. In particular, quantum-dot
SOAs (QD-SOAs) provide higher gain, wider gain bandwidth, and faster gain recovery timethan common SOAs, which have a great advantage in optical signal processing. For all-optical
logic gates, several experimental demonstrations using SOAs and simulations using QDSOAs have been reported.
In these devices, frequency chirp is a well-known phenomenon in which the carrier
frequency changes instantaneously due to a change in the refractive index of the device as
the light intensity changes.
In this year, we demonstrate an all-optical AND logic gate using filter-sliced frequency
chirp in a QD-SOA. To effectively utilize frequency chirp, a probe signal sliced by a high rolloff optical filter is used before injecting into the QD-SOA. We also evaluate and compare thelogic operations based on red and blue frequency chirp in the QD-SOA.

- 15 -

Fig. 2.2.3 Output signal waveforms of logic gates using (left) red and (right) blue frequency
chirp while changing total input power.

Figure 2.2.3 shows the output signal waveforms of the logic gates using red and blue
frequency chirp. In the case of red frequency chirp, it can be clearly seen that the output
signal included patterning effect due to the gain recovery time even if the total power injected
into the QD-SOA was changed. On the other hand, in the case of blue frequency chirp, there
was no critical patterning effect of the output signal by adjusting the total power injected
into the QD-SOA. In particular, when the total power injected into the QD-SOA was set to 2
dBm, the highest extinction ratio of 6.42 dB was obtained. In this setup, we also measured
the bit-error-rate characteristics using a pseudo random bit sequence data, and the error-free
operation of the output signal was successfully achieved. The obtained results showed thatthe logic gate using blue frequency chirp had higher performance than that of the logic gateusing red frequency chirp.

2.2.4 Funds【Grants-in-Aid for Scientific Research】
1. Grant-in-Aid for Scientific Research (C),”Microwave OAM Antenna” (A. Saitou)
2. Grant-in-Aid for Challenging Research (Exploratory) “Research on reconfigurable alloptical logic gates using semiconductor devices” (M. Matsuura)【Commissioned Research】
1. MIC, SCOPE, “Research and development of reconfigurable OAM spatial multiplexing antenna
technology for massive multiple access wireless networks” (R. Ishikawa, K. Honjo, A. Saitou)【Cooperative Research】
1. SoftBank Group Corp. “Low power consumption amplifier” (R. Ishikawa)
2. ROHM Co., Ltd. “High frequency measurement technique for GaN-HEMT” (R. Ishikawa)
3. Fujikura Ltd. “High performance power amplifier for 5th generation mobile communication
systems” (R. Ishikawa, Y. Yamao)
4. Japan Space Systems. “Technical evaluation of high-efficiency power transfer section related to“Research and development project for high efficiency wireless power transfer in space solar
power systems” (R. Ishikawa)
5. Japan Space Systems. “Development of energy-related technology on the lunar surface(organization of technical issues related to electric power) Development and study of equipment,
etc. for power transmission technology demonstration experiments from low-Earth orbit” (R.
Ishikawa)
6. Japan Space Systems. “Study of RF amplifier for wireless power transmission in lunar orbit solar
power generation system” (R. Ishikawa)- 16 -

2.3 Division of Creating Advanced Wireless Systems
2.3.1 Purpose of Division
R&D of Advanced Wireless Systems and Networks contributing to development of society
by sustainable technologies of wireless systems

2.3.2 Research Staffs and Their Specialties
Prof. Koji Ishibashi（Division Leader, Future NW, Distributed NW）
Prof. Takeo Fujii（Future NW, Cognitive Radio, Distributed NW）
Prof. Motoharu Matsuura（Future NW）
Prof. Celimuge Wu (Future NW, Distributed NW)
Associate Prof. Koichi Adachi (Future NW)
Associate Prof. Katsuya Suto (Future NW)

2.3.3 Major Research Results in 2022
[5D Spectrum Database] (Fujii Lab.)In Beyond 5G/6G, non-terrestrial networks (NTNs) such as satellites and drones are
expected to be used to expand the communication area, and frequency management in theheight direction is required. In this study, we designed and developed a 5-dimensional (5D)
spectrum database, which is an extension of the spectrum database of radio environment
information studied in a 2-dimensional (2D) latitude and longitude plane to a 3-dimensional(3D) space including height information, and to 5D space including time and frequency. We
report the details of the design and the results of the tests using experiments. The grid codeof the designed 3D grid is described: As shown in Fig. 2.3-1, for the 2D grid code of latitude
and longitude (2D grid code is an example of 10m grid), symbols indicating the grid size inthe height direction are added based on the height of 0 m (E1:1m, E2:2m, E5:5m, E10:10m).
In addition, "+" is added for points higher than 0 m in elevation and "-" is added for points
lower than 0 m in elevation. A numeric value indicating the grid number based on 0 m
elevation is added after the above codes. By appropriately adding symbols, codes, andnumeric values to the 2D grid code in this way, it is possible to express the elevation range
in any height grid for a 2D grid code of a particular parcel. We report the results of a test of
the database developed on the basis of the above design. In this test, radio maps weregenerated based on the measurement data obtained from an actual experiment, which was
extended to a 3D grid in the height direction and statistically analyzed. The data used in thetest was obtained from an experiment conducted on February 15, 2022. The experiment was
conducted on signals in the local 5G Sub-6 band (4.8 GHz band) operated by Ehime CATV in
Ehime, Japan. As statistical processing parameters, we specified a 2D grid size of 10 m for
latitude and longitude and a grid size of 10 m for height direction (elevation), and generated
radio maps by averaging the data for each 3D grid, which is a 10 m cube. Fig. 2.3-2 shows
the generated radio maps. In this figure, the 3D grid is divided into elevations in 10 m
increments and shown as 2D radio maps. For the present measurement data, three radio
maps were generated for elevations ranging from 40 to 49.999 m, 50 to 59.999 m, and 60 to
69.999 m. Without elevation gridding, the radio map is shown in the lower right corner of Fig.
2.3-2, and this map is the sum of each map divided by elevation. From the above, we haveconfirmed that the developed database enables the recognition of radio space that reflects
the actual 3D space.

- 17 -

100 mFig. 2.3-1. Example of 3D grid codeswith added heigh direction.

Base station

Elevation range: 40 – 49.999 mElevation range: 60 – 69.999 mElevation range: 50 – 59.999 m
Average−100−90
SS-RSRP −80
dBm

No classification of elevation
−110

−120

−130

−140

Fig. 2.3-2. Radio maps generated for each
10m elevation range.

[REM Construction Method under Threatening Environment (Fujii Lab.)
Cognitive radio (CR) is a wireless communication technology that has emerged as apromising solution to address the spectrum scarcity problem by enabling dynamic spectrum
access (DSA). It allows unlicensed users to opportunistically access the licensed spectrum
when it is not in use by licensed users. Cognitive radio networks (CRNs) rely on intelligent
algorithms to sense the spectrum environment, detect available frequencies, and optimize
the use of the spectrum. However, accurate knowledge of the radio environment is crucial
for efficient spectrum management. This has led to the development of the Radio
Environment Map (REM), which provides a comprehensive representation of the radio
environment. The REM enables cognitive radios to make informed decisions on spectrum
access, leading to efficient spectrum utilization and increased network capacity.
However, the open condition may lead some threats for the REM construction. In ourstudy, we consider about when the malicious terminals exist in the environment and rewrite
the sensed information and send false information to the database in order to lead a big
error to the REM. If we do interference analysis or channel allocation based on such map,
it might ruin the CRNs.
In order to deal with such condition, we proposed a Kriging-based Trust Nodes Aided
REM construction system. By adding small amount of the trust node, the system canevaluate real-time comparisons and accumulative total reputations to select reliabledatasets for constructing the REM in a threatening environment. Fig. 2.3-3 shown our
proposed system. As Fig. 2.3-4 shown is the ground truth REM, the Fig. 2.3-5 is the map
under the attacks, Fig 2.3-6 is the map adapted with our proposed algorithm. The proposed
method achieves high map accuracy by monitoring the cumulative behavior of even a small
number of participants.

Fig. 2.3-3 Kriging-based Trust Nodes Aided REM Construction System- 18 -

Fig. 2.3-4 Ground truth

Fig.2.3-5 Under attacking

Fig.2.3-6 Proposed method[Method of Constructing Measurement-based Spectrum Database for Non-Terrestrial
Network] (Fujii Lab.)Due to the popularization of the Internet and the increase in smart devices, effective useof frequency bands is required. To solve this problem, non-terrestrial networks (NTNs) suchas satellites have been attracting attention (shown in Fig. 2.3-7). NTNs are affected byblocking vegetation and buildings on land and changes in positional relationships by using
existing radio propagation models, making it difficult to predict the radio environment.
The measurement-based spectrum database collects radio environment data such as
frequencies, received power, and location information collected by a group of groundterminals. Thus, it is not possible to statistically process the measurement data at thereceiving position. Due to the constant movement of satellites, the received signal strength
intensity with time. Thus, it is not possible to statistically process the measurement data at
the receiving position.
Therefore, we propose a method of statistically processing measurement positions andsatellite positions by grid them using a celestial coordinate system that can grasp the angular
relationship between measurement points and satellites.
Furthermore, actual measurements of GPS satellites were carried out in an environment
where radio wave blocking may occur, and the division angle in the sky was examined basedon the measurement data. Measurement data includes elevation and azimuth angle of thesatellite and the Carrier-to-Noise Ratio: CNR (i.e., received signal strength) data.
We focused the CNR data in which the range of azimuth angle is fixed at 166° to 208° (i.e.,
angle expected to be in non-line of sight (NLOS)), and then the range of elevation angle is 0°
to 20° (angle expected to be in NLOS) and 20° to 30° (angle expected to be in line of sight(LOS)). Based on that CNR data, the average value of the CNR for each elevation angle when
the range of elevation angle is 0° to 30° was calculated. The result is shown in Fig. 2.3-8. It
can be read that the variance of the CNR tends to increase when the elevation angle changes
from the NLOS state to the LOS state around 19°. Also, we calculated the variance of the
CNR for each division angle in the elevation direction. As a result, we found the finer thedivision angle, the smaller the variance of the CNR tends to be.

- 19 -

Fig. 2.3-7. Image of measurement-based
spectrum database for NTNs.

Fig. 2.3-8.

The result of the averagevalue of CNR

A ER[Grant-Free Access for Massive Users] (Koji Ishibashi Lab.)
Future wireless communication such as Beyond 5G and 6G would accommodate a massive
number of devices, as represented by Internet-of-Things (IoT). In order to realize efficient
low-latency data transmission of a massive
number of devices, designing multiple access
schemes is crucial. As one of the promisingtechniques, grant-free non-orthogonal multiple
access (GF-NOMA) has been actively studied. Thebase station (BS) does not exclusively assign radio
resources to active users for data transmission in
GF-NOMA, as shown in Fig. 2.3-9. This academic
year, we have proposed a GF-NOMA scheme
100
based on orthogonal frequency divisionmultiplexing(OFDM)
considering
an10! 1
implementation issue such as carrier frequency
10! 2
offset (CFO). In this scheme, a multi-antenna BS
estimates the active users, channel coefficients,
10! 3
and CFOs using the overlapped pilot signals
10! 4
M M V -A M P (ignoring C F O )spread over both the time and frequency domain.
P rop osed
It is performed via a multiple measurement
G enie-aided M M V -A M P
!5
10
0
5
10
15
20
vector approximate message passing (MMVSN R [dB ]AMP) with space-alternating generalized
Fig. 2.3-10 Activity error rate of the
expectation-maximization (SAGE)-based CFO
proposed GF-NOMA.
update. Fig. 2.3-10 shows the activity error rate
(AER) performance of GF-NOMA with the proposed algorithm. In this figure, MMV-AMP
performance ignoring the effect of CFOs is plotted as a green chain line with triangle
markers. The proposed scheme and MMV-AMP performance with perfect knowledge of
CFOs are plotted as a red solid line with circular markers and a blue dotted line, respectively.
From the figure, the performance of our proposed scheme is comparable to MMV-AMP withperfect knowledge of CFOs, while the performance of MMV-AMP ignoring CFOs draws ahigh error floor.

- 20 -

[Beamforming Design for Cell -Free Massive MIMO Systems] (Koji Ishibashi Lab.)
Network-assisted full-duplex (NAFD) cell-free(CF) massive multiple-input multiple-output(mMIMO) over millimeter wave channels is expected
to be an enabler of 6G systems. NAFD CF-mMIMO
can accommodate uplink and downlink users
simulateneously, as illustrated in Fig 2.3-11, andincreases spectral efficiency dramatically. However,this simultaneous transmission causes
stronginter-user equipment (UE) and inter-access point(AP) interference. To mitigate inter-UE interference,the estimation of channels among UEs is essential
while this estimation is practically difficult,considering the required overhead. Hence,
considering the characteristic of millimeterwave
channels, we proposed the inter-UE channel
estimation method using geographycal informationof UEs and proposed AP allocation and beamforming
design method for mmWave NAFD CF-mMIMO.
Figure 2.3-12 depicts average throughput with thedifferent number of UEs. Besides our proposed
method, SotA with perfect channel state information(CSI) or without inter-UE CSI, and time division
duplex (TDD) are considered as competitors. SotA
with perfect CSI outperforms the proposed method while SotA without inter-UE CSI
exhibits the worst performance. Although our proposed method do not assume perfect CSI,
it can mitigate the inter-UE interference effectively and achieves the performance close to
the SotA with perfect CSI. Moreover, the comparison with “TDD” reveals the effectivenessof NAFD.
90

A varage of total throughput [G bit/s]

80

70

60

50

40

30

N
N
N
N

20

10

16

18

20

22

24

26

= 16, SotA w ith perfect C SI
= 16, P rop osed
= 16, T D D= 16, SotA , w /o inter-U E C SI

28

30

32

N um ber of U E s[Robust Beamforming Design for Millimeter-Wave Channels] (Koji Ishibashi Lab.)
BS
Millimeter-wave (mmWave) communications areUE
expected to be foundations of beyond 5G and 6G
wireless architectures. Recently, various blockage
prediction methods and several coordinated multipoint (CoMP) transmission methods exploitingCPU
blockage information have been proposed to overcome
Fr o n th au l
the vulnerability of mmWave signals, as shown in Fig
2.3-13. However, these methods considered only
single-carrier narrowband channels, which are notappropriate for practical mmWave systems. MmWave
systems usually employ orthogonal frequency division multiplexing (OFDM) to mitigate theeffect of frequency selectivity caused by the large bandwidth. To this end, we proposed a newrobust CoMP transmission scheme against random path blockages and designed tominimize the outage probability of users. Figure 2.3-14 shows the achievable throughput of
proposed and state-of-the-art approaches. In this figure, sum rate maximization (SRM)based CoMP with the knowledge of instantaneous blockage was plotted as a solid curve.
Conventional and proposed outage minimization (OutMin)-based CoMP with blockage- 21 -1
M RT
M M SEO utM in(C onventional,M SG D )Initial b eam (E M bound)
H andover(w / A ctual C SI)
O utM in(P roposed,B M SG D )SR M (w / A ctual C SI)

0.9
0.8
0.7

T arget R ate

0.6

CD F

probability were denoted by a solid line with “+”markers and a dashed line, respectively. The
comparison between the proposed OutMin andconventional OutMin indicates the gain obtainedby the proposed joint design of beamforming andpower and data rate allocation. Furthermore, eventhough SRM-based CoMP ideally exploits theavailable channels during the data transmission,
the proposed OutMin-based CoMP approaches theperformance up to target rates of 16 [Mbps] onlywith path blockage probabilities.

0.5
0.4
0.3
0.2
0.1
0

0

4

8

12

16

20

24

28

32

36

40

A chieved D ata R ate [M bps]

[Optically Powered Transmission Systems for Optical Access Networks]（Matsuura Lab）
In future mobile communications, radio-over-fiber (RoF) that transmits radio-frequency(RF) signals into optical fibers will be one of the key technologies. In order to increase thespeed and the capacity of mobile communications, the use of higher RF signals and a large
number of remote antenna units (RAUs) are needed. In such systems, how to supply power
to a large number of RAUs will be an important issue in future RoF networks.
To drive an RAU without any external power supply, an electrical power of 10 W or more
has to be delivered by power-over-fiber (PWoF). To achieve this, we have proposed a PWoF
using a double-clad fiber (DCF), which compose a single-mode (SM) core for signaltransmission and the surrounded inner cladding for power transmission. On the other hand,in these experiments, the wavelength of feed light was 808 nm, and the power transmission
efficiency was not very high, which limited the efficiency for long-distance transmission. To
solve this problem, we have been investigating and studying the suitable feed lightwavelength and the DCF. In particular, DCFs with pure silica inner cladding have beenshown to provide low-loss power transmission band at 1550 nm. However, the DCF requireda different coupling method between feed light and data signal unlike conventional DCFs,
and it was difficult to obtain high transmission performances of the data signal under highpower feeding.
To improve the power transmission efficiency of PWoF using DCFs, we present a novel
scheme for a DCF, which has pure-silica inner cladding, with low-loss transmission and

Fig. 2.3-15 EVM penalties of transmitted RoF data signals. Insets show constellations of (a)back-to-back and (b) transmitted RoF signals using SSC when feed light power was 9 W.

- 22 -

demonstrate a simultaneous data and power transmission at 1550 nm. As a result, we
successfully achieve not only improvement of the power transmission efficiency, but also hightransmission performance of the simultaneously transmitted RoF data signals.
Figure 2.3-15 shows the EMV penalties to the back-to-back signal of the transmitted RoF
data signals while changing the input feed light power. When the spot-size converter (SSC)
was not used (without and with mode-conditioning fiber (MCF)), the EVM penalties wasincreased over 1%. This was due to the fact that a portion of the RoF data signal experienced
multi-mode transmission, which gave rise to mode dispersion and the effect of crosstalk withthe feed light. On the other hand, when the SSC was used, the EVM penalty was less than
0.6%, and there was no significant increase even if the feed light power was increased. This
result shows that the use of SSC enables not only to provide nearly single-mode propagationof the RoF data signal, but also to avoid the crosstalk between the feed light and RoF data
signal.
[Fuzzy Logic based Client Selection for Federated Learning in Vehicular Networks](Celimuge Wu Lab.)
Federated learning (FL) is a promising paradigm for achieving distributed intelligence byprotecting user privacy in vehicular networks. Considering limited computing andcommunication resources, it is important to select appropriate clients from a huge numberof users to participate in the training process. In vehicular networks, the problem ofchoosing proper clients is particularly complex due to the heterogeneity of network users,
including the differences in the data, computation capability, available throughput, andsamples freshness. We design a fuzzy logic based client selection scheme to address thisissue. The proposed scheme considers the number of local data, computing capability, andnetwork resources of each client participating in FL based on fuzzy logic. In addition torealistic computer simulations, we also design a prototype system (Fig. 2.3-16 left), where
Raspberry Pi and laptops are used as FL clients, and verify the superiority of the proposed
method through extensive experiments (Fig. 2.3-16 right). As shown in the experimental
results, the proposed scheme is able to improve the accuracy of FL significantly as comparedwith the baselines.

Fig. 2.3-16 Client Selection for FL (left: prototype system; right:. accuracy comparison
between the proposed scheme and other baselines).

2.3.4 Funds【Grants-in-Aid for Scientific Research】
1. Scientific Research B “Establishment of Cell-Free Network Architecture for UserCentric Communications”
Koji Ishibashi
2. Scientific Research Fostering Joint International Research Type B “Simultaneous- 23 -

Wireless Information and Power Transfer with Intelligent Reflecting Surface”
Katsuya Suto
3. Scientific Research B “Sensor Networks with High Speed Environmental Adaptation
by Recognition of Synthesizing Wave”
Takeo Fujii (PI belongs to other organization)
4. Scientific Research B “Quantum Optimization Accelerating High-Speed, HighCapacity Wireless Communications”
Koji Ishibashi (PI belongs to other organization)【Commissioned Research】
1. MIC “Highly-Reliable Wireless Access Technology for Advanced 5G Networks”
Koji Ishibashi
2. MIC SCOPE “Flexible LPWA Based on Environmental Dynamics”
Koichi Adachi, Takeo Fujii
3. NICT B5G “Technologies for Next Generation Five Dimensional Mobile
Infrastructures”
Takeo Fujii, Katsuya Suto, Koya Sato
4. MIC “Research and development of advanced optical transmission technology that
contributes to a green society”
Motoharu Matsuura
5. NICT B5G “Construction of a highly efficient wireless communication system using
high power radio-over-fiber transmission”
Motoharu Matsuura
6. NICT JUNO3 “End-to-end network slicing and orchestration in future programmableconverged wireless-optical networks”
Motoharu Matsuura【Cooperative Research】
1. KDDI Research Inc., Motoharu Matsuura
2. NEC Corporation, Takeo Fujii
3. KDDI Research Inc., Koji Ishibashi
4. Ericsson AB, Koji Ishibashi
5. Softbank Corporation, Takeo Fujii
6. Toyota Motor Corporation, Celimuge Wu- 24 -

2.4 Division of Exploring Low Power Wireless2.4.1 Purpose of DivisionThis division is aiming at low power wireless device technologies and application systems,
which become fundamentals for future wireless communication systems. We areinvestigating such low power wireless technologies as super low power LSI design, energy
harvesting technology, power transfer technology by optical fiber, as well as low power
networks by theoretical approach. We also create new wireless application systems using
the low power wireless technologies.
2.4.2 Research Staffs and Their Specialties
Prof. Koichiro Ishibashi (Head of Division, Low-power devices)Prof. Motoharu Matsuura (Radio over Fiber)Prof. Takeo Fujii (Smart meters)
Prof. Koji Ishibashi (Green network and communication theory)
Prof. Ryo Ishikawa (RF energy harvesting)
Associate Professor, Koichi Adachi (LPWA)
2.4.3 Major Research Outcomes in 2022
[Development of Energy Saving Lighting System using Illumination Beat Sensor (Koichiro
Ishibashi Lab, Adachi Lab)A new approach to reduce energy of LED lighting system using Illumination Beat Sensors
is proposed. The sensor is 8g weight and small size totally within credit card size in area andoperates without battery and transmits illumination data to a luminaire by ID signal intervaltime, so that the sensor can be placed anywhere and semi-permanently operates. By making
the lighting system using the Illumination Beat Sensors, total energy of lighting system canbe reduced by 43%. This lighting system can address issue of energy shortage and carbon
zero - emission for the lighting systems anywhere in such places as houses, buildings,
factories and so on.

System Structure
Luminaire 1→Restart←CTL Info.

SerialPW

Luminaire 0

Commander←CTL Info.

PC

Light
from
outsidePW

BeatRX

Luminaire 2

CTL 1
LED

0

Luminaire 3
PW
CTL 3
PW
CTL 2

LED

LED

Light
Intensity
Beat
Sensor 1

Beat
Sensor 0

Illumination Beat
SensorTotal Weight 8 g

2

3

2

3

1

LED

CTL 0

BeatTX

4 Luminaires0

Beat
Sensor 3
Beat
Sensor 2800

4 BeatSensors

Conv.
従来

1

Prop.
提案

600

PWM
400
Duty
(us) 200
ID

0
Total

Fig. 2.4-1 Energy saving lighting system, Illumination Beat Sensor, and Effect of the energy
saving depending on the system.

- 25 -

[Optically Powered Drone for Airborne Base Stations] (Matsuura Lab.)
Mobile communication services are crucial during emergency disasters and temporary events,and future mobile communication systems should be able to provide such services. Airborne
base stations using drones are highly effective as stand-in base stations in areas where theground base stations are inoperable or at temporary event sites. However, it is difficult for
conventional drones to provide mobile communication services without interruption due toflight time limitations caused by their limited battery capacity. Thus, a drone drive with a
non-interrupted power supply is urgently needed.
In this year, we developed an airborne base station that enables drones to be driven andmaneuvered by optical fibers. We simultaneously transmitted radio frequency (RF) data
signals for the airborne base station and control signals for the drone and evaluated thetransmission performances of the RF signals and the controllability of the drone.
Furthermore, we conducted a flight experiment on a medium-sized drone powered by opticalfibers.

Fig. 2.4-2 (a) EVM as a function of SG output power. Dashed line shows EVM of 5.6%. Inset
shows constellation of transmitted RF data signal when SG output power was 2 dBm. (b)Photographs illustrating control of optically controlled drone. Red arrows indicate directionin which the drone is moving.

For a detailed evaluation of the transmission performance of the RF data signal, the errorvector magnitude (EVM) of the transmitted signal was measured; the results are shown in
the left side of Fig. 2.4-2 (a). The dashed line shows an EVM of 5.6%, which is necessary toensure adequate received signal quality for the modulation format used. The inset shows theconstellation of the transmitted RF data signal when the signal generator (SG) output power
was 2 dBm. As the SG output power increases above 0 dBm, the EVM value also increases.
This was due to the nonlinear distortion caused by the excessive electrical power input to thelaser-diode. However, as the SG output power decreased below 0 dBm, the EVM slowly
increased. This indicates signal quality degradation due to the weakening of the signal
component. In contrast, the EVM was below 5.6% over a very wide power range, indicatingthat the received RF data signal had high signal quality. The results indicate that the signaltransmitted to the drone has a sufficient signal quality to be radiated from the airborne basestation.
In order to verify whether the control signals are accurately transmitted by the RoF
transmission, we conducted drone control tests based on the experimental setup. By using
the RF-absorbing sheet, we controlled the drone by radio-over-fiber (RoF) transmission using
a 100 m standard single-mode fiber (SSMF). Photographs illustrating drone control are
shown in the right side of Fig. 2.4-2 (b). We confirmed the operability of the drone via theremote controller (RC) controller by performing eight different control operations, wherein
the drone initiated pairing operations through RoF transmission. This shows that the drone
can be operated using an optical fiber, even without wireless communication.
- 25 - 26 -

[Spectrum Sharing for LPWA Under Intra-system and Inter-system Interference
Constraints] (Fujii Lab.)
Nowadays, depletion of frequency resources has been expected because of a huge numberof low power wide area (LPWA) nodes. Despite this, various LPWA systems with different
communication protocols have been developed according to use cases (e.g., long range wide
area network (LoRaWAN) and wireless smart utility network (Wi-SUN)), utilizing the same
unlicensed Sub-GHz bands. In addition, when many LPWA nodes start to transmit
observation information to gateway (GW), the nodes randomly determine their transmission
timings and frequency channels regardless of the channel occupancy conditions. Therefore,
the intra-system and inter-system interferences on the same band may frequently occur at
an arbitrary system’s GW, which may deteriorate the signal demodulation performance inthe same system.
Thus, we aim to guarantee the demodulation performance under the intra-system andinter-system interference constraints. We propose successive interference cancellation (SIC)
based on cooperation between multiple GWs among multiple LPWA systems. Fig. 2.4-3 shows
the system model. First, the GW which succeeds in demodulating shares the obtained binary
sequence and received waveform to the GW with failing it. Then, the failing GW removes thesignal by adaptive filtering and fast Fourier transform.
Fig. 2.4-4 shows the average PER as a function of SNR with assumption of timesynchronization, in which the two LoRa signals (L1 and L2) and one Wi-SUN signal (W1) aresuperposed with equal received power. The black line indicates the average PER when the
single GW can demodulate only the same system’s signals. The blue and red lines indicate
the average PER when performing SIC at a single GW and between multiple GWs,
respectively. From the black line in Fig. 2.4-4, it is confirmed that a single GW cannot
demodulate ‘L2’. Accordingly, it is shown that ‘L2’ (or ‘L1’) cannot be subtracted accurately asin blue line. In contrast, it can be confirmed that our proposed method achieves suppressionfor ‘L2’ and ‘W1’ because shared ‘L1’ can be accurately subtracted.

Fig. 2.4-3. System model.

Fig. 2.4-4. Average PER as a functionof SNR (w/o time synchronization, {L1,
L2, W1}).

[Packet Transmission Considering Duty-cycle Based on Packet-Level Index Modulation for
LoRaWAN] (Fujii Lab.)In LoRa transmission system, the transmittable time of each channel is limited by duty
cycle (DC). To increase the amount of data can be transmitted under this constraint, packetlevel index modulation (PLIM) has been proposed. PLIM assigns a channel index (CI) and atime slot index (TSI) to the frequency channel and the divided time slot, respectively. The- 27 -

time slot and channel for transmitting packet is selected based on the transmitted data
sequence. This allows additional information to be transmitted by CI and TSI. However, if
the transmitted bit string is biased, the selected transmission channel will also be biased,thus reducing the amount of data that can be transmitted compared to conventional LoRatransmission due to the DC constraints described above. This paper proposes an adaptive CI
exchange method when the occurred CI is biased.
Fig. 2.45. shows the system model for this simulation. In this study, each terminal sends
packets using PLIM and makes CI exchange decisions at regular intervals based on therecorded channel history. The CI exchange decision predicts the transmission time ratio of
each channel based on the packet transmission channel history. The predicted values of eachchannel are compared, and if the maximum difference among all channel pairs exceeds athreshold value, CI exchange is performed on that channel pair.
To evaluate the performance of the proposed method, computer simulations were executedusing the C language. For the bias of the transmitted bit sequence, the packet loss ratio by
DC for each of the conventional PLIM and the proposed method is shown in Fig. 2.4-6.
Simulation results confirm that the number of packets that become untransmittable at theDC can be reduced.

Fig. 2.4-5. System modelFig. 2.4-6. Packet loss rate of DC[DC voltage synthesis of 2.45-GHz-band sub-mW high-efficiency rectifier using zerothreshold GaAs HEMTs]（Ishikawa Lab. ）In order to obtain a sufficient DC output voltage, a DC voltage synthesis configuration has
been developed by using sub-mW-class high-efficiency zero-threshold GaAs HEMT rectifiers
at 2.45-GHz band. A sub-mW-class high-efficiency rectifier has been successfully realizedbased on a resonance control technique on a small-signal condition. In addition, a cold-start
operation is also realized by using a zero-threshold GaAs HEMT. By connecting the DC
output ports of the GaAs HEMT rectifiers in series, a DC output voltage synthesis rectifier
has been constructed. The fabricated GaAs HEMT rectifier exhibited an equivalent RF-toDC power conversion efficiency of 67% and a DC output voltage of 2.1 V at each input powerof 0 dBm (Fig. 2.4-7).

- 28 -

Fig. 2.4-7 Fabricated GaAs HEMT rectifier, and its characteristic[Encryption-then-Compression Technique for Practical Systems] (Koji Ishibashi Lab.）
Wireless sensor networks (WSNs) have to meet low-power consumption and private data
security via encryption. To satisfy these requirements, encryption-then-compression (EtC)
has been studied. Conventional EtC systems
assume that bits in packets follow a Bernoulli
distribution. However, in practical WSNs system,
the source data has a specific structure such asdate, time, and user idendifier. In addition to thedata structure, these data are regularly based onalphanumeric coding system such as ASCII.
Hence, practical data packets do not follow
theoretical Bernoulli distribution, and this gap
between theory and practice would cause theperformance degradation of EtC systems. In thisacademic year, we have proposed a realistic EtC
scheme, considering the ASCII coding and specificpacket structure. Fig. 2.4-8 shows the decoding
performance of the proposed EtC scheme wher thedata packets were obitaned by smart meters inoperation. The results show that our proposed method can compress the packet length byalmost half while the convetional one could not compress the encrypted packets.
[Packet-Level Index Modulation for LoRaWAN] (Adachi Lab.)To overcome the limitation of data rate of low power wide area network (LPWAN), packetlevel index modulation (PLIM) has been proposed. In addition to the payload in the data
packet, additional bit sequences can be transmitted through time slot and frequency channel
selection. However, due to the inexpensive hardware of LPWAN, the clock speed between an
end node (EN) and a gateway (GW) differ from each other. This difference results in time slot
misdetection of PLIM. We have previously proposed a clock drift estimation andcompensation for PLIM and implemented in commercially available LoRaWAN systems.
LoRa mini-JP and Dragino LG308 are used as EN and GW, respectively. The functionalities
are implemented by the LMiC library and OpenWrt. The data flow considered in thisexperiment is shown in Fig. 2.4-9. Each terminal obtains the temperature every 1 min andsends the obtained data to the GW using PLIM. Once the GW receives the data, it estimatesand compensates for the clock drift and detects the time slot and frequency channel to decodethe PLIM bit sequence. Then, the GW transfers the decoded PLIM sequence to the server via
the MQTT protocol. The developed system has functionalities to adaptively change LoRa

- 29 -

1 . LoRa uplink

2 . MQTTPLIM demodulated
measurement data

PLIM modulated 0011
measurement data 010...1011

0011

PLIM parameters + rule set

010...1011

Operational parameters

4 . LoRa dow nlink LoRaWANGW LG308

Server

3 . SCP

Fig. 2.4-9. Data flow
24

24

20

20

16

16

12

12

8

8

4

4

0

100

200

300

400

500

600

0

100

200

300

400

500

600

(a) w/o compensation(b) with compensation
Fig. 2.4-10. Experimental resultstransmission
parameterssuch
asinformationcollection
intervals and available
frequency channels. Fig.
2.4-10shows
theexperimental
results.
The time slot length isset to 1 [sec], and each
EN transmits its data
packet by selecting one of
the combinations with 8
frequency channels and32 time slots. Thus,
PLIM
canconveyadditional 8 bits. In theexperiment, 5 bits areused for representing
integer numbers and theremaining 3 bits are fordecimal numbers. As canbe seen from the figure,time slot misdetection
occurs as time elapses if
the proposed method is
not adopted and resultsin error. On the other
hand,
the
proposed

Fig. 2.4-11. CAD-based PLIM with enhanced index mapping

Fig. 2.4-12. Throughput performance- 30 -

method achieves accurate time slot detection.
Last year, we proposed a flexible index mapping (FIM) that flexibly changes the mapping
between the frequency-time slot index and bit sequence. However, in PLIM with flexible
index mapping (FIM), an EN must discard the data packet if the EN cannot use the selected
frequency-time slot resource. Thus, the system throughput performance degrades whenmany ENs exist in the system. To overcome such shortcomings, we have proposed an
improved version of FIM, where each EN divides a transmission frame into several
subframes and performs channel activity detection (CAD) in each subframe. Doing so can
improve the transmission opportunity compared to the original FIM. To be specific, as Fig.
2.4-11 shows, the available resources of 𝑅 are divided into subframe of 𝑉(𝑑). Then, PLIM
bit sequence is expressed by the resource within each subframe. Here, 𝑉(𝑑) is the numberof frame division that is uniquely determined by frame division index 𝑑.
Each EN selects one transmission resource based on the PLIM bit sequence and performs
CAD at the starting time of the selected resource. If the EN does not detect any signal the
EN transmits a data packet. On the other hand, if it detects any signal, it reperforms resource
selection and CAD in the subsequent subframe. If the EN detects the ongoing transmission,
the EN repeats this procedure until the end of corresponding frame. Simulation results (Fig.
2.4-12) have shown that the proposed method can increase the throughput by about 20%
compared to the conventional method.
[Resource Allocation for LoRaWAN] (Adachi Lab.)
Low-power wide area networks (LPWANs),
1.0such as long-range wide area networks(LoRaWAN), are increasingly adopted as a
0.8
communication standard for wireless sensor
networks. In particular, LPWAN has been
0.6
adopted for systems that periodically collect0.4
sensor data, such as environmental
monitoring. However, continuous packet
0.2
collisions may occur in periodic traffic systems
due to adopting a simple random-access
0.0
500
1000
1500
2000
scheme in LPWAN. In addition, the use of lowNumber of nodecost nodes results in clock drift, renderingtransmission cycle changes unintentionally.
Thus, this study proposes a centralized resource allocation scheme comprising clock driftcompensation, frequency channel allocation, and transmission timing offset allocation to
overcome these challenges. In the proposed scheme, GW compensates for the transmission
cycle of the node based on the observed clock drift. Subsequently, the GW predicted future
packet collision based on the periodic traffic feature and sequentially determined andallocated the transmission offset and frequency channel for each node. In particular, theproposed scheme can exploit a secondary effect of clock drift (continuous packet collision
avoidance) by sequential allocation. Furthermore, based on probability, each node discardeda packet to avoid continuous packet collisions owing to clock drift compensation. The
performance evaluation considering the LoRaWAN network has been conducted. Fig. 2.3-13
shows the computer simulation results of the PDR performance for each number of nodes.
“LBT” denotes the CS-based autonomous decentralized packet collision avoidance method,and “SMAC” denotes the existing centralized control packet collision avoidance method for
periodic traffic.
As shown in Fig. 2.4-13, the proposed scheme can improve the average packet delivery rate

- 31 -

(PDR) performance compared to the other method because it can allocate appropriate radio
resources while utilizing clock drift.
2.4.4 Funds[Grants-in-Aid for Scientific Research]
1. JST CREST “Practical applications of RFEH technology by combination of SSFET rectenna
and piezoelectric transformer” in the area of Scientific Innovation for Energy Harvesting
Technology, (Koichiro Ishibashi, Ryo. Ishikawa, and Koji Ishibashi)
2. Grant-in-Aid for Scientific Research (C), “Microwave rectifiers for flexible wireless powertransfer system in emergency” (R. Ishikawa)【Commissioned Research】

1. MIC SCOPE “Flexible LPWA Based on Environmental Dynamics”
Koichi Adachi, Takeo Fujii- 32 -

3．令和４年度

外部発表リスト

著書【1】 松浦基晴, “次世代高速通信に対応する光回路実装, デバイスの開発,” 「超高速・大容量伝送を実現するための光信号処理技術（第 12 章, 第 6 節）, 技術情報協会, 2022 年
査読付き一般論文【1】 Shuto Fukue, Hiroki Iimori, Giuseppe T. F. De Abreu, and Koji Ishibashi,

【2】

【3】

【4】

【5】

【6】
【7】

【8】

【9】

“Joint Access Configuration and Beamforming for Cell-Free Massive MIMO
Systems With Dynamic TDD,” IEEE Access, vol. 10, pp. 40130-40149, Apr.
2022.
Kosuke Suzuki, Koichi Adachi, Mai Ohta, Osamu Takyu, and Takeo Fujii,“Flexible Index Mapping Scheme for Packet-Level Index Modulation,” IEEE
Wireless Commun. Lett., vol.11, no.4, pp. 703-706, Apr. 2022,
DOI:10.1109/LWC.2022.3140420.
Ying Gao and Takeo Fujii, “An Improvement of Security Scheme for Radio
Environment Map under Massive Attacking,” IEEE Access, vol. 10, pp. 4550845521, Apr. 2022. DOI: 10.1109/ACCESS.2022.3170478
Shusuke Narieda and Takeo Fujii, “Transmit Power Allocation Schemes for
Performance Improvement of Poor Conditioned End Devices in LPWAN,”
IEEE Access, vol. 10, pp. 42778-42790, Apr. 2022. DOI:
10.1109/ACCESS.2022.3168139
Keigo Ando, Hiroki Iimori, Giuseppe T. F. de Abreu, and Koji Ishibashi, “UserHeterogeneous Cell-Free Massive MIMO Downlink and Uplink Beamforming
via Tensor Decomposition,” IEEE Open J. Commun. Soc., vol. 3, pp. 740-758,
Apr. 2022.
Motoharu Matsuura, “Power-over-fiber using double-clad fibers (Invited),”IEEE J. Lightwave Technol., vol. 40, no. 10, pp. 3187-3196, May 2022.
Keita Katagiri, Koya Sato, Kei Inage, and Takeo Fujii, “Radio Map
Extrapolation Using Compensated Empirical CDF Under InterferenceLimited Observations,” IEEE Access, vol. 10, pp. 54936-54946, May 2022,
DOI: 10.1109/ACCESS.2022.3174702.
Jun Nagai, Koji Ishibashi, and Yasushi Yamao, “Signal Quality Improvement
in Downlink Power Domain NOMA with Blind Nonlinear Compensator and
Frequency Domain Equalizer,” IEICE Trans. Commun., vol. E105-B, no. 5, pp.
648-656, May 2022.
Osamu Takyu, Gaku Kobayashi, Koichi Adachi, Mai Ohta, and Takeo Fujii,- 33 -

“Estimation Based on Chirp Modulation for Desired and Interference Powerand Channel Occupancy Ratio in LoRa,” Sensors, vol. 22, no. 11, p.4140, May
2022, doi: 10.3390/s22114140.
【10】 Marco Sarmiento, Khai-Duy Nguyen, Ckristian Duran, Ronaldo Serrano,
Trong-Thuc Hoang, Koichiro Ishibashi, and Cong-Kha Pham, “Systems on a
Chip With 8 and 32 Bits Processors in 0.18-m Technology for IoT
Applications,” IEEE Trans. Circuits Syst. II: Express Br., vol. 69, no. 5, pp.
2438-2442, May 2022
【11】 Takanori Hara and Koji Ishibashi, “Blind Multiple Measurement Vector AMP
Based on Expectation Maximization for Grant-Free NOMA,” IEEE WirelessCommun. Lett., vol. 11, no. 6, pp. 1201-1205, Jun. 2022.
【12】 Weiyu Zhou, Satoshi Ono, and Koji Wada, “A Multi-Layer SIW Resonator
Loaded with Asymmetric E-Shaped Slot-Lines for a Miniaturized Tri-Band
BPF with Low Radiation Loss,” IEICE Trans. Electron., vol. E105-C, no. 7, pp.
349-357, Jul. 2022.
【13】 Masashi Wakaiki, Katsuya Suto, and Izumi Masubuchi, “Cell Zooming withMasked Data for Off-Grid Small Cell Networks: Distributed Optimization
Approach,” IEEE Trans. Control Systems Technol., vol. 30, no. 4, pp. 10636536, Jul. 2022.
【14】 Jiaqi Zou, Rui Liu, Chenwei Wang, Yuanhao Cui, Zixuan Zou, Songlin Sun,
and Koichi Adachi, “Aiming in Harsh Environments: A New Framework for
Flexible and Adaptive Resource Management,” IEEE Network, vol. 36, no. 4,
pp. 70-77, Jul./Aug. 2022.
【15】 Kohei Tsurumi, Aoto Kaburaki, Koichi Adachi, Osamu Takyu, Mai Ohta, andTakeo Fujii, “Simple Clock Drift Estimation & Compensation for Packet-Level
Index Modulation and its Implementation in LoRaWAN,” IEEE IEEE
Internet Things J., vol. 9, no. 16, pp. 15089-15099, Aug. 2022, DOI:
10.1109/JIOT.2022.3148767.
【16】 Hiroki Iimori, Takumi Takahashi, Koji Ishibashi, Giuseppe T. F. de Abreu,
David Gonzalez G., and Osvaldo Gonsa, “Joint Activity and Channel
Estimation for Extra-Large MIMO Systems,” IEEE Trans. Wireless Commun.,vol. 21, no. 9, pp. 7253-7270, Sept. 2022.
【17】 Koji Ishibashi, Takanori Hara, Sota Uchimura, Tetsuya Iye, Yoshimi Fujii,
Takahide Murakami, and Hiroyuki Shinbo, “User-Centric Design ofMillimeter Wave Communications for Beyond 5G and 6G (Invited Paper),”
IEICE Trans. Commun., vol. E105-B, no. 10, pp. 1117-1129, Oct. 2022.
【18】 Akira Saitou, Ryo Ishikawa, and Kazuhiko Honjo, “Pattern synthesis ofspatial eigenmodes exploiting spherical conformal array,” IEICE Trans.

- 34 -Electron., vol. E105-B, no. 10, pp. 1231–1239, Oct. 2022.
【19】 Natsuki Shindo, Taiki Kobatake, Denis Masson, Simon Fafard, and Motoharu

Matsuura, “Optically powered and controlled drones using optical fibers for
airborne base stations,” Photonics, vol. 9, no. 11, Nov. 2022, doi:
10.3390/photonics9110882【20】 Xing An, Celimuge Wu, Yangfei Lin, Min Lin, Tsutomu Yoshinaga, andYusheng Ji, “Multi-Robot Systems and Cooperative Object Transport:
Communications, Platforms, and Challenges,” IEEE Open Journal of theComputer Society, vol.4, pp.23-36, Jan. 2023.
【21】 Keigo Ando, Koji Ishibashi, and Giuseppe T. F. de Abreu, “Robust Tensor
Decomposition for Heterogeneous Beamforming Under Imperfect Channel
State Information,” IEEE Open J. Signal Process., vol. 4, pp. 89-98, Feb. 2023.
【22】 Masafumi Oda, Osamu Takyu, Mai Ohta, Takeo Fujii, and Koichi Adachi,“Position Estimation of Radio Source Based on Fingerprinting With PhysicalWireless Parameter Conversion Sensor Networks,” IEEE Access, vol. 11, pp.
1843-12857, Feb. 2023, 10.1109/ACCESS.2023.3242611.
【23】 Yuma Katsuki, Giuseppe T. F. de Abreu, Koji Ishibashi, and Naoki Ishikawa,“A New Noncoherent Gaussian Signaling Scheme for Low Probability of
Detection Communications,” IEEE Wireless Commun. Lett., vol. 12, no. 3, pp.
545-549, Mar. 2023.
【24】 Toshi Ito, Masafumi Oda, Osamu Takyu, Mai Ohta, Takeo Fujii, and Koichi
Adachi, “Three-level detection using the collision detection method inphysical,” Sensors, vol. 23, no. 6, p. 3308, Mar. 2023, doi: 10.3390/s23063308.
【25】 M. Matsuura, “Simultaneous data signal and power transmission using adouble-clad fiber (Invited),” The Review of Laser Engineering, vol. 51, no. 3,
pp. 147-151, Mar., 2023.
査読付き国際会議プロシーディングス等【1】 Natsuki Shindo, Taiki Kobatake, Motoharu Matsuura, Demis Masson, andSimon Fafard, “Flight Demonstration of Power-over-Fiber Drone for Aerial
Base Stations,” in Proc. The 4th Optical Wireless and Fiber Power
Transmission Conference (OWPT 2022), OWPTp-01, Yokohama, Apr. 2022.
【2】 Kai Murakami, Hikaru Mamiya, and Motoharu Matsuura, “Simultaneous
Data and Power Transmission Using a Double-Clad Fiber with Low-Loss
Transmission Band at 1550 nm,” in Proc. The 4th Optical Wireless and Fiber
Power Transmission Conference (OWPT 2022), OWPTp-05, Yokohama, Apr.
2022.

- 35 -

【3】 Hiroki Iimori, Takumi Takahashi, Hyeon Seok Rou, Koji Ishibashi, Giuseppe
T. F. de Abreu, David Gonzalez G., and Osvaldo Gonsa, “Grant-Free Accessfor Extra-Large MIMO Systems Subject to Spatial Non-Stationarity,” in Proc.
IEEE ICC 2022, Seoul, South Korea (Hybrid), pp. 1758-1762, May 2022.
【4】 Takanori Hara, Hiroki Iimori, and Koji Ishibashi, “Grant-Free NOMA Using
Time-Delay Domain for Low-Latency Massive Access over MIMO-OFDM,” inProc. IEEE ICC 2022, Seoul, South Korea (Hybrid), pp. 3526-3531, May 2022.
【5】 Ying Gao and Takeo Fujii, “Terminal Selection Based on Multi-armed Bandit
under Threatening Environment for Radio Environment Map Construction,”in Proc. IEEE VTC2022-Spring, Online, pp. 1-6, Jun. 2022.
【6】 Tetsuyuki Itoh, Masaki Sagara, Junichi Tsuda, and Motoharu Matsuura,“Photonic Digital to Analog Conversion Using Supercontinuum Multi-Channel
Clocks,”in
Proc.
OptoElectronics
andCommunications

Conference/International Conference on Photonics in Switching andComputing (OECC/PSC 2022), ME1-1, Toyama, Jul. 2022.
【7】 Kai Murakami, Hikaru Mamiya, and Motoharu Matsuura, “Improvement ofPower Transmission Efficiency in Power-over-Fiber Using a Double-Clad
Fiber at 1550 nm,” in Proc. OptoElectronics and Communications

Conference/International Conference on Photonics in Switching andComputing (OECC/PSC 2022), TuC1-5, Toyama, Jul. 2022.
【8】 Taishi Takemoto, Junichi Tsuda, and Motoharu Matsuura, “All-Optical AND
Logic Gate Using Filter-Sliced Frequency Chirp in a QD-SOA,” in Proc.

OptoElectronics and Communications Conference/International Conference
on Photonics in Switching and Computing (OECC/PSC 2022), WP-F3, Toyama,Jul. 2022.
【9】 Noriyuki Oki, Atsuki Mukoda, Ayumu Ueda, and Takeo Fujii, “Device
Adaptive Control Method Considering Power Consumption for Pedestrian-toInfrastructure Communications,” in Proc. ICUFN 2022, Barcelona, Spain, Jul.
2022.
【10】 Ryo Miyamoto, Shunsuke Narieda, Takeo Fujii, and Hiroshi Naruse,“Characteristics of RSSI Kriging Interpolated Value in Neighborhood of
Buildings,” in Proc. ICUFN 2022, Barcelona, Spain, Jul. 2022.
【11】 Ryuji Miyamoto, Osamu Takyu, Hiroshi Fujiwara, Koichi Adachi, Mai Ohta,
and Takeo Fujii, “Performance Evaluation of Highly Efficient Information
Collection Methods by Trend Analysis of Sensor Information Using PreLearning,” in Proc. ICUFN 2022, Barcelona, Spain, Jul. 2022.

- 36 -

【12】 Toshi Ito, Osamu Takyu, Mai Ohta, Takeo Fujii, and Koichi Adachi, “HighSensitivity Detection Method for Signals in PhyC-SN,” in Proc. ICUFN 2022,
Barcelona, Spain, Jul. 2022. (Best Paper Award)【13】 Shunsuke Narieda and Takeo Fujii, “Characteristics of Transmit Power
Allocation for Poor Conditioned End Devices in LPWAN with Peak Detection
Based Carrier Sense,” in Proc. ICUFN 2022, Barcelona, Spain, July 2022.
【14】 Mai Ohta, Takeo Fujii “Differential Packet Level Index Modulation for Low
Power Wide Area System,” in Proc. ICUFN 2022, Barcelona, Spain, July 2022.
【15】 Amano Masaki, Mai Duc Tho, Ishibashi Koichiro, Sun Guanghao, Nguyen Vu
Trung, Le Thi Hoi, and Nguyen Thi Hoa, “Deep Learning Approach forclassifying Bacteria Types Using morphology of Bacterial Colony,” in Proc.
Annu. Int. Conf. IEEE Eng. Med. Biol. Soc. (EMBC 2022), Jul. 2022.
【16】 Ayaka Urabe, Koji Ishibashi, MohammadJavad Salehi, and Anti Tölli,“Beamforming Design for Wireless Coded Caching with Different Cache Sizes,”
in Proc. IEEE SPAWC 2022, Oulu, Finland, pp. 1-5, Jul. 2022.
【17】 Kohei Ueda, Takanori Hara, and Koji Ishibashi, “Iterative Activity Detection
and Carrier Frequency Offset Estimation for Grant-Free NOMA,” in Proc.
IEEE PIMRC 2022, Virtual, pp. 1-6, Sept. 2022.
【18】 Ying GAO and Takeo Fujii, “Kriging-based Trust Nodes Aided REM
Construction under Threatening Environment,” in Proc. IEEE VTC2022-Fall,
London, UK, Sept. 2022.
【19】 Hirofumi Nakajo and Takeo Fujii, “Blockage Prediction for Millimeter-wave
Communications Based on People Flow Data,” in Proc. IEEE VTC2022-Fall,
London, UK, Sept. 2022.
【20】 Ayumu Ueda, Takeo Fujii, and Atsuki Mukoda, “Adaptive Communication
System Selection Method for V2X Using Radio Environment Database,” inProc. ITS World Congress 2022, Los Angeles, USA, Sept. 2022.
【21】 Atsuki Mukoda, Ayumu Ueda, Keita Katagiri, and Takeo Fujii, “Constructing
Packet Delivery Rate-based Map Using Confidence Interval,” in Proc. ITSWorld Congress 2022, Los Angeles, USA, Sept. 2022.
【22】 Takanori Hara and Koji Ishibashi “Completely-Blind Multiple Measurement
Vector AMP for Massive Grant-Free NOMA,” in Proc. IEEE CTW 2022,
Marbella, Spain, Oct. 2022.

- 37 -

【23】 Kengo Ando, Koji Ishibashi, and Giuseppe T. F. de Abreu, “Robust Tensor
Decomposition for CF-mMIMO with Heterogeneous Users and Imperfect CSI,”in Proc. IEEE CTW 2022, Marbella, Spain, Oct. 2022.
【24】 Natsuki Miyoshi, Tomoyuki Kawashima, Shusuke Narieda, Takeo Fujii, andHiroshi Naruse, “Measurement of sub-GHz Band LPWA Propagation at HalfWavelength Intervals,” in Proc. IEEE Future Networks World Forum 2022,
pp.429-433, Oct. 2022.
【25】 Hoang Thi Yen, Van-Phuc Hoang, Nguyen Huu Son, Quang Kien Trinh, Xuan
Nam Tran, Koichiro Ishibashi, and Guanghao Sun, “Real-Time Medical Radarbased Vital Sign Monitoring System Implemented with Signal Quality
Classification Algorithm,” in Proc. Int. Conf. on Advanced Technologies forCommun. (ATC 2022), Nha Trang, Vietnam, Oct. 2022.
【26】 Nguyen Huu Son, Hoang Thi Yen, Guanghao Sun, and Koichiro Ishibashi,“Real-Time Medical Radar-based Vital Sign Monitoring System Implemented
with Signal Quality Classification Algorithm,” in Proc. Int. Conf. on Advanced
Technologies for Commun. (ATC 2022), Nha Trang, Vietnam, Oct. 2022.
【27】 Tuan-Anh Tran and Koichiro Ishibashi, “High-Accuracy and Long-Range
Energy Harvesting Beat Sensor with LoRa,” in Proc. 2022 IEEE Sensors,
Dallas, TX, USA, Oct.-Nov. 2022, pp. 1-4.
【28】 Seiya Otsuka, Hiroki Iimori, Kengo Ando, Giuseppe T. F. de Abreu, Koji
Ishibashi, and Naoki Ishikawa, “Analysis of Secret Key Agreement Protocol
for Massive MIMO Systems,” in Proc. CISIS 2022, Salamanca, Spain, pp. 8694, Nov. 2022.
【29】 Tomoki. Sugiura, Tetsuya Iye, Shohei Takaya, Yuki Susukida, Yoshimi Fujii,
Sota Uchimura, and Koji Ishibashi, “Realization of Multi-Point CoordinatedBeamforming Over Millimeter-Wave Channels with Random Blockage,” inProc. ICETC 2022, Tokyo, Japan, O5-3, Nov. 2022.
【30】 Shinichiro Kakuda, Takeo Fujii, and Shusuke Narieda, “Successive
Interference Cancellation for Signal Demodulation of Multiple LPWA
Systems,” in Proc. APSIPA ASC 2022, Chiang Mai, Thailand, Nov. 2022.
【31】 Nao Ashizawa, Kazuhiko Honjo, and Ryo Ishikawa, “Back-off expansion byoutphasing combination with simple power amplifiers for quasi-millimeterwave operation,” in Proc. 2022 Asia-Pacific Microwave Conference, pp. 91-93,
Yokohama, Japan, Nov. 2022.
【32】 Tsuyoshi Yoshida, Kazuhiko Honjo, and Ryo Ishikawa, “DC voltage synthesisof 2.45-GHz-band sub-mW high-efficiency rectifier using zero-threshold GaAs
HEMTs,” in Proc. 2022 Asia-Pacific Microwave Conference, pp. 572-574,
Yokohama, Japan, Dec. 2022.

- 38 -

【33】 Taki Nagata, Kazuhiko Honjo, Ryo Ishikawa, “DC-feedback-mode transistor
rectifier/voltage-doubler diode rectifier for negative gate biasing to microwave
power amplifiers,” in Proc. 2022 Asia-Pacific Microwave Conference, pp. 446448, Yokohama, Japan, Dec. 2022.
【34】 Katsuya Ishihara, Akira Saitou, Kazuhiko Honjo, and Ryo Ishikawa,“Optimizations of curvature of concave reflectors and feed-point azimuths ofloop antennas for long-range OAM communication,” in Proc. 2022 Asia-PacificMicrowave Conference, pp. 393-395, Yokohama, Japan, Dec. 2022.
【35】 Koichiro Ishibashi and Yuki Ogawa, “Energy Saving LED Lighting Systemusing Illumination Beat Sensors,” in Proc. 2023 IEEE Int. Conf. on Consumer
Electronics (ICCE), Las Vegas, NV, USA, Jan. 2023, pp. 1-2.
【36】 Marco Sarmiento, Khai-Duy Nguyen, Ronaldo Serrano, Trong-Thuc Hoang,
Koichiro Ishibashi, and Cong-Kha Pham, “A 440nW RISC-V-Based Systemon-Chip on Silicon-On-Thin-BOX (SOTB) for IoT Applications,” in Proc. ASPDAC 2023, Tokyo, Japan, Jan. 2023
【37】 Shuto Fukue, Giuseppe T. F. de Abreu, and Koji Ishibashi, “NetworkAssisted Full-Duplex Millimeter-Wave Cell-Free Massive MIMO with
Localization-Aided Inter-User Channel Estimation,” in Proc. ICOIN 2023,
Bangkok, Kingdom of Thailand, pp. 13-18, Jan. 2023.
【38】 Sunao Miyamoto, Shota Yamada, and Takeo Fujii, “Height Pattern
Estimation Method Using the Combination of Radio Map and 3D Map forSpectrum Sharing,” in Proc. ICOIN 2023, Bangkok, Thailand, Jan. 2023.
【39】 Shougo Matsuo, Sunao Miyamoto, Hirofumi Nakajo, and Takeo Fujii, “BeamPattern Estimation of 5G Millimeter-Wave Base Station Based on Radio Map
and Multi-Beam Antenna Model at 28GHz,” in Proc. ICOIN 2023, Bangkok,
Thailand, Jan. 2023.
【40】 Taro Miyamoto, Shusuke Narieda, Takeo Fujii, and Hiroshi Naruse,“Measurement of Sub-GHz Band LPWA Radiowave Propagation on Each Floor
in Indoor Environment,” in Proc. ICOIN 2023, Bangkok, Thailand, Jan. 2023.
【41】 Daisuke Kumamoto, Shusuke Narieda, Takeo Fujii, and Hiroshi Naruse,“Lower Bound for the Number of Accommodable End-Devices in LPWAN with
Multiple Interferences,” in Proc. ICOIN 2023, Bangkok, Thailand, Jan. 2023.
【42】 Yusuke Itayama, Hirofumi Nakajo, Shougo Matsuo, and Takeo Fujii,“Measurement-Based Spectrum Database for Non-Terrestrial Networks,” inProc. ICOIN 2023, Bangkok, Thailand, Jan. 2023.

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【43】 Shusuke Narieda and Takeo Fujii, “Robustness to Digital Power Adjustment
in Transmit Power Allocation for Poor Conditioned LPWA End Devices,” inProc. ICOIN 2023, Bangkok, Thailand, Jan. 2023.
【44】 Junichiro Yamada and Katsuya Suto, “ Exploring Pseudo-Analog Video
Transmission for Edge-AI Vision Applications,” in Proc. IEEE Consumer
Commun. & Networking Conf. 2023, Jan. 2023, pp. 1-2.
【45】 Hirofumi Nakajo, Yusuke Itayama, Shougo Matsuo, and Takeo Fujii, “5DSpectrum Database,” in Proc. ICAIIC 2023, Bali, Indonesia, Feb. 2023.
【46】 Ryuji Munakata, Takuma Kuno, Yojiro Mori, Shih-Chun Lin, Motoharu
Matsuura, Suresh Subramaniam, and Hiroshi Hasegawa, “Architecture andPerformance Evaluation of Bundled-path-routing Multi-band Optical
Networks Author block,” in Proc. 48th The Optical Fiber Communication
Conference and Exposition (OFC 2023), M4G.8, San Diego, USA, Mar. 2023.
【47】 Sota Uchimura, Giuseppe T. F. de Abreu, and Koji Ishibashi, “Hybrid
Beamforming for Outage-Minimization in Frequency Selective MillimeterWave Channels,” in Proc. IEEE WCNC 2023, Glasgow, United Kingdom, pp.
1-6, Mar. 2023.
【48】 Katsuya Suto, Shinsuke Bannai, Koya Sato, and Takeo Fujii, “Propagation
Graph Representation Learning and Its Implementation in Direct Path
Represent,” in Proc. IEEE WCNC 2023, Glasgow, UK, Mar. 2023.
【49】 Aoto Kaburaki, Koichi Adachi, Osamu Takyu, Mai Ohta, and Takeo Fujii,“Resource Allocation for Periodic Traffic in Wireless Sensor Network,” in Proc.
IEEE WCNC International Workshop on Smart Spectrum (IWSS 2023),
Glasgow, UK, Mar. 2023.

国際会議招待講演【1】 Ryo Ishikawa, “A high-gain and high-efficiency amplifier module for DC-RF power
conversion in wireless power transfer systems,” URSI combined Atlantic/Asia-PacificRadio Science Conference 2022, Mo-WS2-PM2-1, Gran Canaria (Hybrid), May 2022.
【2】 Takeo Fujii, “Data Driven Spectrum Management for 6G Networks,” IEEE
INFOCOM Workshop PerAI-6G 2022, May 2022. (Keynote)【3】 [Keynote Speech] Koichiro Ishibashi, “Signal Processing of I and Q Output
From Doppler Radar to Acquire Vital Signs,” Workshop on Intelligent Signal
Processing for Communications, June 16th, 2022, Hanoi.
【4】 [Invited] Koichiro Ishibashi, “Low power Wake up Receiver for IoT,”
International Conference on IC Design and Technology (ICICDT 2022), Sep.
21th, 2022, Hanoi Sept. 2022.

- 40 -

【5】 [Keynote Speech] Koichiro Ishibashi, “Bacteria Classification by Small-Scale
Deep Learning,” NAFOSTED Conference on Information and Computer
Science (NICS 2022), Oct. 31st, 2022, Ho Chi Minh City.
【6】 Motoharu Matsuura, “Opportunities and challenges of power-over-fiber in 6G
networks,” European Conference on Optical Communications (ECOC 2022),
Workshop “Which technologies will be needed for 6G?”, Basel, Switzerland,
Sept. 2022.
【7】 [Invited] Koichiro Ishibashi, “RF EH Technologies and Its Potential
Applications, “ ISI Symposium, Hanoi, Oct. 24th, 2022 (On line)【8】 [Key note speech] Koichiro Ishibashi, “RF Energy Harvesting Technology andIoT Applications,” Int. Conf. on Computing and Communication Technologies,(RIVF 2022) Dec. 20th, 2022, Ho Chi Minh City.
【9】 [Invited] Koichiro Ishibashi, “Beat Sensor with LoRa powered by Energy
Harvesting,” Vietnam National University Information Technology Institute
Seminar, Dec. 25, 2022.
【10】 Motoharu Matsuura, “Power-over-fiber technologies using double-clad fibers
for remote antenna units in mobile networks,” SPIE Photonics West 2023, San
Francisco, US, Jan. - Feb. 2023.

国内会議招待講演【1】 石橋孝一郎、井田次郎、柳谷隆彦、平山裕司、伊東建治、牧野茂、石川亮、範公可、石橋功至、“RF エネルギーハーベスティング技術と IOT 応用の新展開”、応用物理学会、招待講演、2022 年 9 月 20 日
【2】 村上夏尉、藤田卓、松浦基晴、“1550 nm 帯給電光を用いた光ファイバ給電による伝送効率の改善,” 信学技報、vol. 122、no. 379、OCS2022-88、pp. 91-94、2023
年 2 月.
【3】 小畠大輝、神藤夏季、松浦基晴、“光ファイバ給電ドローン基地局のための光合分
波と電気重畳による信号伝送特性評価,” 信学技報、vol. 122、no. 398、PN202247、pp. 28-31、2023 年 3 月.
【4】 和田光司、“広帯域フィルタとその分波回路への応用,” 信学技報、vol. 122、no.
411、MW2022-178、pp. 118-123、Mar.2023.マイクロ波研究会
解説・評論【1】 石橋孝一郎、「電波発電を用いた IoT センサの動作検証」電気設備学会誌 2022
年8月

- 41 -

学会口頭発表【1】 ヤチョンカ ワムア、黒須礼尚、旭瑞歩、八木秀樹、石橋功至、“拡張可能な
Polarization-Adjusted Convolutional 符号とそのレートレス符号への応用、”
信学技報、vol. 122、no. 25、IT2022-3、pp. 13-18、2022 年 5 月.
【2】 宮本隆司、田久修、藤原洋志、安達宏一、太田真衣、藤井威生、“センサ情報の傾向分析を利用した高効率な情報収集法の特性評価、”信学技報、vol.122、no.12、SR2022-15、pp.61-66、2022 年 5 月.
【3】 宮本隆司、田久修、藤原洋志、安達宏一、太田真衣、藤井威生、“センサ情報の傾
向分析を利用した高効率な情報収集法の特性評価、”信学技報、vol. 122、no. 12、SR2022-14、pp. 61-66、2022 年 5 月.
【4】 Tuan-Anh Tran and Koichiro Ishibashi、“Low Power Beat Sensor with LoRa
and Power Supplied by RF Energy Harvesting,”システムと LSI のワークショ
ップ、2022 年５月．
【5】 磯野直樹、安藤研吾、石橋功至、“ランダムなユニタリ行列を用いた秘匿プリコード OFDM 伝送、”信学技報、vol. 122、no. 73、RCS2022-42、pp. 108-113、2022
年 6 月.
【6】 石川亮、髙山洋一郎、本城和彦、“小型出力合成回路を用いた 4.5 GHz 帯 GaNHEMT アウトフェージング増幅器 MMIC、”信学技報、vol. 122、no. 64、MW202225、pp. 13-18、2022 年 6 月.
【7】 上田康平、原郁紀、石橋功至、“搬送波周波数オフセット存在下におけるグラン
トフリー非直交多元接続のための繰り返しアクティブユーザ検出、”信学技報、vol. 122、no. 73、RCS2022-43、pp. 114-119、2022 年 7 月.
【8】 石川亮、髙山洋一郎、本城和彦、“小型出力合成回路を用いた 4.5 GHz 帯 GaNHEMT アウトフェージング増幅器 MMIC、”信学技報、vol. 122、no. 64、MW202225、pp. 13-18、2022 年 6 月.
【9】 山田準一郎、須藤克弥、“疑似アナログ通信方式を用いた物体検出 AI の精度評
価、
”信学技法、vol. 122、no. 107、SR2022-28、pp. 36-40、2022 年 7 月．
【10】 藤井和貴、須藤克弥、“静的遮蔽空間における通信品質改善のための IRS 配置手法、”信学技法、vol. 122、no. 107、SR2022-31、pp. 54-60、2022 年 7 月．
【11】 中條宏郁、藤井威生、“人流データを活用したミリ波通信の遮蔽予測、”信学技報、vol. 122、no. 107、SR2022-42、pp. 96-103、2022 年 7 月.
【12】 伊藤 利、田久 修、太田真衣、藤井威生、安達宏一、“物理量変換一括収集法における信号の高感度検出法、”信学技報、vol. 122、no. 107、SR2022-43、pp. 104109、2022 年 7 月.
【13】 大屋諒悟、角田真一朗、藤井威生、田久修、太田真衣,安達宏一、“送信時間制限を考慮したパケット型インデックス変調方式の検討、”信学技報、、vol. 122、no.
107、SR2022-44、pp. 110-115、2022 年 7 月.

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【14】 伊藤利、田久修、太田真衣、藤井威生、安達宏一、“物理量変換一括収集法における信号の高感度検出法、”信学技報、vol. 122、no. 107、SR2022-43、pp. 104109、2022 年 7 月.
【15】 大屋諒悟、角田真一朗、藤井威生、田久修、太田真衣、安達宏一、“送信時間制
限を考慮したパケット型インデックス変調方式の検討、”信学技報、vol.122、no.107、SR2022-44、pp.110-115、2022 年 7 月.
【16】 宮本隆司、田久修、藤原洋志、安達宏一、太田真衣、藤井威生、“［ショートペーパー］パケット型インデックス変調における集約精度を高める最適インデック
ス設計、”信学技報、vol. 122、no. 107、SR2022-37、pp. 74-78、2022 年 7 月.
【17】 米崎晴貴、井田次郎、森貴之、石橋孝一郎、“極低電圧動作を狙った Steep SS“Dual-Gate 型 PN-Body Tied SOI-FET”、信学技報、vol. 122、no. 148、SDM202238、pp. 17-20、2022 年 8 月.
【18】 蕪木碧仁、安達宏一、太田真衣、田久修、藤井威生、“LPWAN におけるクロック
ドリフトを活かしたリソース割り当て法、”信学技報、vol.122、no.164、RCS2022111、pp.78-83、2022 年 8 月.
【19】 熊田遼汰、安達宏一、“LoRaWAN における WPT 干渉除去法、”信学技報、vol.122、no.164、RCS2022-112、pp.84-89、2022 年 8 月.
【20】 内村颯汰、飯盛寛貴、アブレウ ジュゼッペ、石橋功至、“OFDM を用いたミリ波通信のための確率的遮蔽を考慮したロバストビームフォーミング設計、”信学技報、vol. 122、no. 164、RCS2022-121、pp. 138-143、2022 年 8 月.
【21】 鈴木康介、安達宏一、太田真衣、田久修、藤井威生、“パケット型インデックス
変調におけるチャネルアクティビティ検出を用いたインデックスマッピング手法の検討、”信学技報、vol.122、no.164、RCS2022-122、pp.144-149、2022 年 8月.
【22】 松尾祥吾、中條宏郁、宮本直、藤井威生、若藤健司、ニ瓶亮太、吉田昂平、“電波マップとマルチビームアンテナモデルに基づいたミリ波ビームパターン推定
手法の検討、”信学技報、RCS2022-120、pp. 132-137、2022 年 8 月.
【23】 蕪木碧仁、安達宏一、田久修、太田真衣、藤井威生、“LPWAN におけるクロック
ドリフトを活かしたリソース割り当て法,”信学技報、vol. 122、no. 164、RCS2022-111、pp. 78-83、2022 年 8 月.
【24】 塩竹明人、小野哲、和田光司、“高い中心周波数可変率を持つチューナブル BPF
に関する研究、”信学技報、vol. 122、no. 183、MW2022-69、pp. 7-12、2022 年
9 月.
【25】 天野雅貴、DucTho Ma、GuanghaoSun、NguyenVu Trung、Le Thi Hoi、NguyenThi
Ho、石橋孝一郎、“敵対的生成ネットワークを用いた機械学習によるバクテリア
コロニーの分類精度向上、”信学技報、vol. 122、no. 188、MI2022-61、pp. 4952、2022 年 9 月．

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【26】 鶴見康平、蕪木碧仁、安達宏一、“チャープインデックス空間分割に基づく LoRa
信号の誤検出確率低減手法、”信学ソ大、B-5-64、2022 年 9 月.
【27】 蕪木碧仁、安達宏一、田久修、太田真衣、藤井威生、“クロックドリフト補償誤差に起因するパケット衝突回避法の検討、”信学ソ大、B-5-66、2022 年 9 月.
【28】 成枝秀介、藤井威生、“信号検出確率・誤警報確率の設計値が電力検出キャリア
センスを用いた sub-GHz 帯 LPWAN に与える影響,”信学ソ大、B-17-9、2022 年 9月.
【29】 宮本隆司、田久修、藤原洋志、安達宏一、太田真衣、藤井威生、“パケット型イ
ンデックス変調における送信制御を活用した情報収集法の特性評価、”信学ソ大、
B-17-10、2022 年 9 月.
【30】 伊藤利、田久修、安達宏一、太田真衣、藤井威生、“無線物理量変換一括収集法
における長区間 FFT による信号検出法、”信学ソ大、B-17-11、2022 年 9 月【31】 芦沢直、本城和彦、石川亮、“50Ω設計増幅器を用いた準ミリ波帯アウトフェージング動作に関する一検討、”信学ソ大、C-2-8、2022 年 9 月.
【32】 板山雄祐、中條宏郁、松尾祥吾、藤井威生、“非地上系ネットワークにおける無線空間データベースの検討、”信学ソ大、B-17-6、2022 年 9 月.
【33】 有賀高志郎、藤井威生、“学習を用いた環境適応無線 MAC プロトコル設計の検討、”RISING、2022 年 10 月.
【34】 Ying GAO、Takeo Fujii、“A Trustworthy Approach for Radio Environment
Map Construction in CRNs、”RISING、2022 年 10 月.
【35】 伊藤利、田久修、太田真衣、藤井威生、安達宏一、“受信アンテナ選択による無線物理量変換一括収集法の衝突検知の高検出化,”RISING、2022 年 10 月.
【36】 宮本隆司、田久修、藤原洋志、安達宏一、太田真衣、藤井威生、“［ショートペーパー］パケット型インデックス変調における送信制御を考慮した最適インデックス設計の改良、”信学技報、vol. 122、no. 243、SR2022-49、pp. 24-28、2022
年 11 月.
【37】 太田真衣、藤井威生、安達宏一、田久修、“［招待講演］パケット型インデック
ス変調方式の実用化検討について、”信学技報、vol. 122、no. 243、SR2022-50、
pp. 29、2022 年 11 月.
【38】 伊藤利、田久修、太田真衣、藤井威生、安達宏一、“［ショートペーパー］物理量変換一括収集法における搬送波周波数オフセットの切り替えによる収集精度の向上、”信学技報、vol. 122、no. 243、SR2022-59、pp. 78-83、2022 年 11 月.
【39】 棚木拓海、安達宏一、“マルチユーザ MEC システムにおける移動ユーザの経路
設計及び資源割当、”信学技報、vol. 122、no. 252、RCS2022-155、pp. 1-6、2022 年 11 月.

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【40】 志田洋人、鈴木康介、安達宏一、田久修、太田真衣、藤井威生、“周波数チャネ
ル毎の DC 環境下におけるパケット型インデックス変調の検討、”信学技報、vol.
122、no. 252、RCS2022-156、pp. 7-12、2022 年 11 月.
【41】 福榮秀都、アブレウ ジュゼッペ、石橋功至、“ネットワーク全二重通信を用いたミリ波セルフリー大規模 MIMO における位置情報を用いた端末間干渉の影響抑制に関する一検討、”信学技報、vol. 122、no. 252、RCS2022-164、pp. 55-60、2022 年 11 月.
【42】 長田多喜、本城和彦、石川亮、“マイクロ波電力増幅器への負ゲートバイアス
印加用直流帰還型ゼロ閾値 GaAs HEMT 整流器および倍電圧ダイオード整流器、”
信学技報、vol. 122、no. 250、MW2022-123、pp. 77-80、2022 年 11 月.
【43】 吉田剛、石川亮、本城和彦、“ゼロしきい値 GaAs HEMT を使用したワイヤレス
電力伝送用サブ mW 動作 2.45 GHz 帯高効率整流器の直流電圧合成法、”信学技報、vol. 122、no. 250、MW2022-122、pp. 73-76、2022 年 11 月.
【44】 芦沢直、本城和彦、石川亮、“準ミリ波帯 50Ω設計電力増幅器を使用したアウ
トフェージング動作による出力バックオフ性能改善の一検討、”信学技報、vol.
122、no. 250、MW2022-111、pp. 13-18、2022 年 11 月.
【45】 角田真一朗、藤井威生、成枝秀介、“複数 GW 間連携に基づく LPWA マルチシステ
ム間逐次干渉除去技術の検討、”信学技報、vol. 122、no. 277、SRW2022-16、pp.
1-6、2022 年 11 月.
【46】 隈元大輔、成枝秀介、藤井威生、成瀬央、“複数干渉波環境を想定した LPWAN の収容可能端末数下限値の導出、”信学技報、vol. 122、no. 277、SR2022-47、pp.
1-6、2022 年 11 月.
【47】 宮本隆司、田久修、藤原洋志、安達宏一、太田真衣、藤井威生、“パケット型イ
ンデックス変調における送信制御を考慮した最適インデックス設計の改良、”信
学技報、vol. 122、no. 243、SR2022-49、pp. 15-19、2022 年 11 月.
【48】 吉村拓也、向田敦紀、沖典之、上田有由夢、藤井威生、“歩路間通信における消費電力と通信信頼性を考慮した端末送信間隔制御手法の検討、”信学技報、vol.
122、no. 243、SR2022-57、pp. 64-70、2022 年 11 月.
【49】 向田敦紀、藤井威生、“無線環境データベースを用いた V2X における無線アクセス技術の適応選択、”信学技報、vol. 122、no. 243、SR2022-58、pp. 71-77、2022
年 11 月.
【50】 太田真衣、藤井威生、安達宏一、田久修、“パケット型インデックス変調方式の実用化検討について、”信学技報、vol. 122、no. 243、SR2022-50、pp. 29、2022
年 11 月.
【51】 中條宏郁、板山雄祐、松尾祥吾、藤井威生、“［技術展示］5 次元無線空間データ
ベース、”信学技報、vol. 122、no. 243、SR2022-56、pp. 58-63、2022 年 11 月.
【52】 伊藤利、田久修、太田真衣、藤井威生、安達宏一、“物理量変換一括収集法における搬送波周波数オフセットの切り替えによる収集精度の向上、”信学技報、vol.

- 45 -

122、no. 243、SR2022-59、pp. 78-83、2022 年 11 月.
【53】 須藤克弥、坂内信允、“ドローンを用いた電波観測による 3 次元空間補間性能の実験的評価、”信学技法、vol. 122、no. 243、SR2022-62、pp. 94-96、2022 年 11月．
【54】 成枝秀介、藤井威生、“Sub-GHz 帯 LPWAN における電力検出キャリアセンスの信号検出レベルのセルフチューニング、”信学技報、vol. 122、no. 243、SR202269、pp. 120-125、2022 年 11 月.
【55】 成枝秀介、藤井威生、“雑音電力推定誤差が電力検出キャリアセンスを用いた
Sub-GHz 帯 LPWAN に与える影響、”信学技報、vol. 122、no. 243、SR2022-70、
pp. 126-128、2022 年 11 月.
【56】 大原晟弥、石橋孝一郎,「RF タグ向けエネルギーハーベスティング電源の検討」,
電子情報通信学会、集積回路研究会、学生・若手研究会、2022 年 12 月．
【57】 内村颯汰、アブレウ ジュゼッペ、石橋功至、“多地点協調 OFDM ミリ波通信シ
ステムのためのアウテージ最小化ハイブリッドビームフォーミング設計、”第 45
回情報理論とその応用シンポジウム、pp. 307-312、2022 年 12 月.
【58】 上田康平、原郁紀、石橋功至、“OFDM を用いたグラントフリー非直交多元接続のための期待値最大化による搬送波周波数オフセット補償、”第 45 回情報理論とその応用シンポジウム、pp. 82-87、2022 年 12 月.
【59】 N. W. Moe Thet and K. Ishibashi、“Resource Allocation in Downlink NOMAOFDM System with Coexistence of URLLC and eMBB Users、”第 45 回情報理論とその応用シンポジウム、pp. 77-81、2022 年 12 月.
【60】 吉田拓実、高橋拓海、石橋功至、衣斐信介、三瓶政一、“符号化大規模 MIMO 検
出のためのビーム領域局所的 LMMSE 出力の尤度情報合成に関する一検討、”第 45
回情報理論とその応用シンポジウム、pp. 301-306、2022 年 12 月.
【61】 石原克弥、斉藤昭、本城和彦、石川亮、“ループアンテナアレイ遠距離 OAM 多重通信システムにおける凹面反射鏡および給電点方位の最適化、”信学技報、vol.
122、no. 313、MW2022-139、pp. 38-42、2022 年 12 月.
【62】 平山尚貴、安達宏一、“到来方向推定精度向上のための使用アンテナ素子選択手法の検討、”信学技報、vol. 122、no. 357、RCS2022-230、pp. 126-131、2023
年 1 月.
【63】 本城和彦、“［招待講演］産業競争力の源泉としてのマイクロ波半導体・回路、”
信学技報、vol. 122、no. 371、MW2022-156、pp. 51-54、2023 年 1 月.
【64】 成島章太、和田光司、肖 鳳超、“欠陥接地構造と抵抗装荷による広帯域な吸収型マイクロストリップ線路コモンモードフィルタに関する検討、”信学技報、vol. 122、no. 360、CAS2022-92、pp. 145-150、2023 年 1 月.
【65】 谷内渉,和田光司、“2 系統電源で中心周波数と通過帯域幅の可変なチューナブ
ル LPF とチューナブル HPF で構成されたチューナブル BPF に関する検討、”信学
技報、vol. 122、no. 360、CAS2022-93、pp. 151-156、2023 年 1 月.

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【66】 大口宏人、和田光司、“多層 FSIW 共振器の基本特性とその分波回路への応用に関する検討、”信学技報、vol. 122、no. 360、CAS2022-94、pp. 157-162、2023
年 1 月.
【67】 石村康大、和田光司、川口則幸、“リング共振器とインタディジタル結合を用いた 21GHz 帯広帯域マイクロストリップ線路バンドパスフィルタに関する検討、”
信学技報、vol. 122、no. 360、CAS2022-95、pp. 163-167、2023 年 1 月.
【68】 成枝秀介、
藤井威生、“電力検出キャリアセンスを用いた異パケット長混在 LPWANの特性,”信学技報、vol. 122、no. 364、SR2022-72、pp. 7-9、2023 年 1 月.
【69】 成枝秀介、藤井威生、“Sub-GHz 帯 LPWAN における電力検出キャリアセンスの検
出レベル最適化、”信学技報、vol. 122、no. 364、SR2022-79、pp. 43-47、2023
年 1 月.
【70】 板山雄祐、中條宏郁、松尾祥吾、藤井威生、“非地上系ネットワーク向け無線空間データベースの実験的評価、”信学技報、vol. 122、no. 364、SR2022-80、pp.
48-53、2023 年 1 月.
【71】 香取稜、松浦基晴、“半導体光増幅器内で発生する周波数チャープの測定法の性能評価、”信学技報、vol. 122、no. 398、PN2022-54、pp. 62-66、2023 年 3 月.
【72】 岡本聡、山中直明、久保亮吾、松浦基晴、津田裕之、“大電力伝送光ファイバ無線による Beyond 5G モバイルフロントホール、”信学技報、vol. 122、no. 398、PN2022-56、pp. 70-76、沖縄県立博物館、2023 年 3 月.
【73】 藤田卓、矢口勇也、松浦基晴、“ダブルクラッド光ファイバを用いた波長 980 nm
帯光ファイバ給電における電力伝送高効率化に関する研究、”電子情報通信学会
フォトニックネットワーク研究会 学生ワークショップ、pn2023-stws-1、沖縄県立博物館、2023 年 3 月.
【74】 石山貴大、木村俊平、栗本崇、津田裕之、岡本聡、山中直明、松浦基晴、“グリーン社会の実現に向けた新しい光アクセス網システム -新構造光ファイバを使用したエネルギー伝送・高多分岐化技術-、”電子情報通信学会フォトニックネ
ットワーク研究会 学生ワークショップ、pn2023-stws-6、沖縄県立博物館、2023
年 3 月.
【75】 藤井威生、“［依頼講演］多次元無線空間把握とその活用による将来の無線通信,”
信学技報、vol. 122、no. 400、SR2022-84、pp. 4-9、2023 年 3 月.
【76】 成枝秀介、藤井威生、“電力検出キャリアセンスを用いた LoRaWAN の特性,”信学技報、vol. 122、no. 400、SR2022-95、pp. 50-53、2023 年 3 月.
【77】 美濃夏貴、須藤克弥,“超解像を活用した WebRTC における軽量深層学習モデ
ルに関する検討,”信学技法、vol. 122、no. 406、NS2022-231、pp. 368-371、2023
年 3 月．

- 47 -

【78】 内村颯汰、石橋功至、飯盛寛貴、クライネ パウロ、マロムソキ サボルチ、“ミリ波通信のための圧縮センシングに基づいた低演算通信路追従法、”信学技報、vol. 122、no. 399、RCS2022-268、pp. 124-129、2023 年 3 月.
【79】 石原克弥、斉藤昭、本城和彦、石川亮、“高次モードを利用した OAM 多重通信用準ミリ波帯ループアンテナアレイ、”信学総大、B-1-101、2023 年 3 月.
【80】 北山観行、斉藤昭、石原克弥、内田海斗、本城和彦、石川亮、“遠距離 OAM 多重
通信のビームステアリングの検討、”信学総大、B-1-100、2023 年 3 月.
【81】 熊田遼汰、安達宏一、“LoRaWAN におけるマルチキャリア WPT 干渉除去法に関する検討、”信学総大、B-5-149、2023 年 3 月 10 日.
【82】 成枝秀介、藤井威生、“悪条件下以外のエンドデバイスからのネットワーク負荷が電力検出キャリアセンスを用いた Sub-GHz 帯 LPWAN に与える影響、”
信学総大、
B-17-11、2023 年 3 月.
【83】 大原晟弥、石橋孝一郎,「RF タグ向けエネルギーハーベスティング電源の検討」,
電子情報通信学会、集積回路研究会、学生・若手研究会、2022 年 12 月．
【84】 藤井威生、“５次元の無線環境把握と周波数共用,”信学総大、BS-4-3、2023 年
3 月.
【85】 山本薫臣、本城和彦、高山洋一郎、石川亮、“3 入力電力レベル最適化設計による 3.7 GHz GaN HEMT ドハティ増幅器、”信学総大、C-2-2、2023 年 3 月.
【86】 山本薫臣、本城和彦、高山洋一郎、石川亮、“3 入力電力レベル最適化設計による 3.7 GHz GaN HEMT ドハティ増幅器のバックオフ性能改善に関する研究、”信学技報、vol. 122、no. 411、MW2022-163、pp. 37-41、2023 年 3 月.
【87】 谷井宏成,和田光司,大野貴信,“左手系伝送線路と右手系伝送線路を用いたマ
イクロストリップ線路フィルタとその応用に関する一検討、”第 37 回エレクト
ロニクス実装学会春季講演大会論文集、13P3-1、2023 年 3 月.
【88】 佐藤雄介,和田光司、“DSPSL 構造とリング共振器による広帯域通過特性を有す
る平衡型フィルタを用いたダイプレクサに関する一検討、”第 37 回エレクトロニクス実装学会春季講演大会論文集、13P3-2、2023 年 3 月.

シンポジウム講演【1】 石川亮、本城和彦、“マイクロ波 SSPS 送電部 DC/RF 変換用高効率増幅器の開発状況、”第 42 回宇宙エネルギーシンポジウム、2023 年 3 月.
その他の講演【1】 Koji Ishibashi, “Promising technologies for Beyond5G/6G,” IEEE PIMRC 2022
Panel04, Sept. 2022.
【2】 藤井威生,“５次元の無線環境把握とモビリティへの応用、”福島浜通り次世代モ- 48 -

ビリティセミナー2022 年度第 1 回、南相馬市、2022 年 11 月（招待講演）【3】 石川亮、“マイクロ波 WPT における送電部高効率 DC/RF 変換回路技術、”無線
電力伝送研究専門委員会【第 7 回ワークショップ】無線電力伝送における回路技
術の基礎と応用、2022 年 12 月
【4】 石川亮、“無線電力送電用マイクロ波高効率増幅器の開発状況、”令和 4 年度第 2回マイクロ波無線送電技術ビジネス化研究会、2023 年 2 月.
【5】 石橋孝一郎「エネルギーハーベスティング Beat Sensor とこれを用いた省エネ
照明システム」、電気通信大学 新技術紹介フェア 2023 冬～カーボンニュートラ
ル特集、2023 年 2 月 28 日、On line.
【6】 石橋孝一郎「エネルギーハーベスティング Beat Sensor とその応用展開」、ＵＥ
ＣアライアンスセンターＩＣＴワークショップ、2023 年 2 月 14 日、電気通信大
学

受賞【1】 芦沢直、2022 年度 電子情報通信学会 マイクロ波研究会 学生研究優秀発表賞【2】 OWPT 2022 Paper Award (N. Shindo, T. Kobatake, M. Matsuura, D. Masson,
and S. Fafard, “Flight demonstration of power-over-fiber drone for aerial basestations,” The 4th Optical Wireless and Fiber Power Transmission Conference(OWPT 2022), OWPTp-01, Yokohama, 2022.)【3】 OWPT 2022 Student Paper Award (K. Murakami, H. Mamiya, and M.
Matsuura, “Simultaneous data and power transmission using a double-clad
fiber with low-loss transmission band at 1550 nm,” The 4th Optical Wirelessand Fiber Power Transmission Conference (OWPT 2022), OWPTp-05,
Yokohama, April 2022)【4】 2022 年度 PN 若手研究賞（神藤夏季, 小畠大輝, 松浦基晴, “空中基地局に向けた
光ファイバ給電ドローンの飛翔実験,” 電子情報通信学会フォトニックネットワ
ーク研究会, PN2021-77, 2022 年．）【5】 向田敦紀，2022 年電子情報通信学会スマート無線研究会研究奨励賞，2023 年 1月（藤井研・前期博士課程学生）【6】 須藤克哉，2022 年電子情報通信学会スマート無線研究会研究奨励賞，2023 年 1月【7】 藤井威生，第 33 回電波功績賞 総務大臣表彰 電波産業会，2022 年 6 月【8】 藤井威生，電波の日関東総合通信局長表彰 総務省関東総合通信局，2022 年 6 月【9】 平山尚貴，2022 年度 IEICE RCS 研究会「RCS 研究会初年度発表者コンペティション」優秀賞受賞，2023 年 1 月（安達研・前期博士課程学生）【10】 安藤研吾，2021 年度電子情報通信学会無線通信システム（RCS）研究会活動奨- 49 -

励賞，2022 年 6 月（石橋（功）研・前期博士課程学生）【11】 中 條 宏 郁 , IEEE VTS Tokyo/Japan Chapter 2022 Young Researcher’s
Encouragement Award, 2022 年 9 月（藤井研・博士後期課程学生）【12】 磯野直樹，2022 年度 IEICE RCS 研究会「初めての研究会」優秀発表賞，2022
年 6 月（石橋（功）研学生・博士前期課程学生）【13】 Best Student Paper Award on ATC 2022
【14】 内村颯太，令和４年度目黒会賞，2023 年 3 月（石橋（功）研・博士前期課程学生）【15】 奥井滉史，令和４年度目黒会賞，2023 年 3 月（石橋（功）研・学部生）【16】 三輪健太，令和４年度目黒会賞，2023 年 3 月（石橋（功）研・学部生）【17】 内村颯太，令和４年度修士論文優秀発表賞，2023 年 3 月（石橋（功）研・博士
前期課程学生）【18】 鈴木康介，令和４年度修士論文優秀発表賞，2023 年 3 月（安達研・博士前期課
程学生）【19】 奥井滉史，令和４年度卒業論文優秀発表賞，2023 年 3 月（石橋（功）研・学部生）【20】 國井瑠偉，令和４年度卒業論文優秀発表賞，2023 年 3 月（石橋（功）研・学部生）【21】 照井貫太，令和４年度卒業論文優秀発表賞，2023 年 3 月（石橋（功）研・学部生）【22】 三輪健太，令和４年度卒業論文優秀発表賞，2023 年 3 月（石橋（功）研・学部生）【23】 更屋貴大，令和４年度卒業論文優秀発表賞，2023 年 3 月（安達研・学部生）【24】 園田晟也，令和４年度卒業論文優秀発表賞，2023 年 3 月（安達研・学部生）【25】 靏見康平，令和４年度学長表彰，2023 年 3 月（安達研・博士前期課程学生）【26】 向田敦紀，令和４年度学長表彰，2023 年 3 月（藤井研・博士前期課程学生）【27】 中條宏郁，令和４年度学長表彰，2023 年 3 月（藤井研・博士後期課程学生）【28】 Taro Miyamoto, Shusuke Narieda, Takeo Fujii, Hiroshi Naruse, The 37th
International Conference on Information Networking (ICOIN) Best Paper
Award, 2023 年 1 月【29】 Gao Ying，電子情報通信学会超知性ネットワーキングに関する分野横断型研究
会 RISING2022 優秀ポスター発表賞，2022 年 11 月（藤井研・博士後期課程学生）【30】 原郁紀，2022 年度電気通信普及財団テレコムシステム技術学生賞，2023 年 3月（石橋（功）研・博士後期課程修了生）- 50 -

特許【1】 石橋孝一郎、小川勇貴、「照明システム」、特願 2022-111922、2022 年 7 月 12 日
【2】 内村颯汰、飯盛寛貴、アブレウ ジュゼッペ、石橋功至、「基地局、ビームフォー
ミング方法およびビームフォーミングプログラム」、特願 2022-112198、日本、
2022 年 7 月 13 日
【3】 田久修、宮本隆司、藤原洋志、藤井威生、安達宏一、「データ伝送方式」、特願 2022125777、2022 年 8 月 5 日【4】 田久修、宮本隆司、藤原洋志、藤井威生、安達宏一、「データ伝送方法」、特願 2022125783、2022 年 8 月 5 日【5】 大塚啓人、斉藤昭、本城和彦、石川亮、, “ループアンテナの給電装置,” 日本国特許第 7161750 号, 2022 年 10 月 19 日.
【6】 石橋功至、谷津崚太、柴田悠宇、遠藤秀樹、土岐爽真、「通信システム，通信方法
およびプログラム」、特願 2022-192845、日本、2022 年 12 月 1 日【7】 S. Uchimura, K. Ishibashi, H. Iimori, P. Klaine and S. Malomsoky, No.

PCT/SE2022/051210, Dec. 20, 2022.
【8】 松浦基晴、「ダブルクラッド光ファイバおよび光ファイバ給電・信号伝送システム」、特願 2023-008721、2023 年 1 月 24 日
【9】 安達宏一、熊田遼汰、受信装置、受信方法および受信プログラム、特願 2023021566、2023 年 2 月 15 日
【10】 上田康平、
石橋功至、「通信システム、
基地局および通信方法」、
特願 2023-052725、
日本、2023 年 3 月 29 日

広報・報道発表【1】 Beyond 5G・6G 実現のためのセルフリー大規模 MIMO 向け ダイナミック TDD技術を開発 -従来の約２倍の周波数利用効率を実現-, 電通大ニュースリリース,
2022 年 5 月 9 日【2】 石橋孝一郎教授（情報・ネットワーク工学専攻）が CEATEC 2022 へ出展【10月 18 日～21 日開催】
（電通大 HP に掲載、2022 年 10 月 19 日）- 51 -