Technical Program

9th Kansai Microwave Meeting for Young Engineers
Kyoto Institute of Technology, Matsugasaki Campus, Kyoto
July 2, 2016
Organized by IEEE Microwave Theory and Techniques Society Kansai Chapter
Supported by Kyoto Institute of Technology

TIME SCHEDULE
9:25-9:30

Opening

9:30-10:35

Session MTT16-A

10:35-10:45

Break time

10:45-11:50

Session MTT16-B

11:50-13:00

Lunch time

13:00-14:05

Session MTT16-C

14:05-14:15

Break time

14:15-15:20

Session MTT16-D

15:20-15:30

Break time

15:30-16:22

Session MTT16-E

16:22-16:30

Break time

16:30-17:22

Session MTT16-F

18:00-20:00

Banquet1

Session MTT16-A 9:30- Chair:
9:30-9:43(MTT16-A-1) Demonstration of Circularly-Polarized Leaky Wave Anttena Based on Pseudo-Traveling
Wave Reasonance(o)Kubo Yuki, Keisuke Ninomiya, Tetsuya Ueda, Andrey Porokhnyuk, Tatsuo Itoh
Kyoto Institute of Technology
9:43-9:56(MTT16-A-2) Study on Re-radiation Characteristics of Rectenna Harmonics for a Harmonics Based
Retrodirective System(o)Shogo Kawashima
Kyoto University
9:56-10:09(MTT16-A-3) Multistep rectangular horn loading grooves with elliptical beam for dual-polarization(o)Reiko Omi, Mikio Tsuji, Hiroyuki Deguchi
Doshisha University
10:09-10:22(MTT16-A-4) Studies on a Fabric Feed Line Sewn to a Flexible Slot Antenna(o)Yuto Ishii
Kyoto Institute of Technology
10:22-10:35(MTT16-A-5) Linear-to-circular polarization reflectarray with arbitrarily shaped elements(o)Hiroki Yamada, Hiroyuki Deguchi, Mikio Tsuji
Doshisha University
Break time 10:35-10:45
Session MTT16-B 10:45- Chair:
10:45-10:58(MTT16-B-1) Study on Operational-Amplifier-Based Negative Impedance Converters to Realize nonFoster Elements(o)Shoji Yamanaka, Yasushi Horii
Kansai University
10:58-11:11(MTT16-B-2) Equivalent Circuit Model of Planar Meta-atoms with Retarded Electromagnetic Coupling(o)Ryoma Nakata, Tohlu Matsushima, Takashi Hisakado, Osami Wada
Kyoto University
11:11-11:24(MTT16-B-3) Study on Linvill’s Negative Impedance Converters for Generation of Pure Non-Foster
Reactance(o)Kenichi Matsumoto, Yasushi Horii
Kansai University
11:24-11:37(MTT16-B-4) Considerations for Loss Mechanism and Improvement of Artificial Dielectric Resonator(o)Yulin Song, Toshio Ishizaki
Ryukoku University2

11:37-11:50(MTT16-B-5) Study on Equivalent Circuit Models for Helmholtz Resonators for Design of Future
Acoustic Metamaterials(o)Yuki Utoku, Yasushi Horii
Kansai University
Lunch time 11:50-13:00
Session MTT16-C 13:00- Chair:
13:00-13:13(MTT16-C-1) Excitation Circuit with Variable Capacitors for Resonator-Coupled WPT System(o)Takehiro Toi, Tetsuya Ishida, Toshio Ishizaki
Ryukoku University
13:13-13:26(MTT16-C-2) Study on a Rectifier for Microwave Power Transfer with Intermittent Input Signal(o)Takashi Hirakawa, Naoki Shinohara
Kyoto university
13:26-13:39(MTT16-C-3) Switchable Power Receiving Unit for Mobile WPT System Providing Power to Multiple
Vehicles(o)Kohei Yamamoto
Ryukoku University
13:39-13:52(MTT16-C-4) Multiple-Input Multiple-Output Dynamic Charging Using Multiple Parallel Line Feeders(o)Brou William-Fabrice, Duong Quang Thang, Minoru Okada
Nara Institute of Science and Technology
13:52-14:05(MTT16-C-5) Power Transfer Experiment of Magnetically Coupled WPT System for EVs through Tires(o)Yuki Kawazoe, Yangjun Zhang, Ikuo Awai
Ryukoku University

Break time 14:05-14:15
Session MTT16-D 14:15- Chair:
14:15-14:28(MTT16-D-1) Proposal and basic study of a transparent water shield for the magnetically coupled WPTsystem -Toward resolution of EMC problems(o)Kentaro Kawabe
Ryukoku University
14:28-14:41(MTT16-D-2) Effect of Bush Growth on Radio Wave Propagation in 920 MHz Band(o)Ryosuke Yoshimura
Kyoto Institute of Technology

3

14:41-14:54(MTT16-D-3) Study on Conductive Effects of Water for a WPT system Applied for Robot Fish(o)Tatuya Hiraiwa
Ryukoku University
14:54-15:07(MTT16-D-4) Signal Interference Analysis Model In Near-Field Coupling Communication(o)Ryo Takeuchi
Kyoto Institute of Technology
15:07-15:20(MTT16-D-5) Miniaturized Amplifier Module for Millimeter-wave Wireless Communication and Power
Transfer System(o)Hayato Matsuo
Ryukoku University

Break time 15:20-15:30
Session MTT16-E 15:30- Chair:
15:30-15:43(MTT16-E-1) A Small-Sized Oscillator Using Dielectric Resonator for Microwave Surgical Instruments(o)Yosuke Yokoyama
Ryukoku University
15:43-15:56(MTT16-E-2) Study on Characteristics of a Single-Mode Resonator for Microwave Heating(o)Daichi Nishio, Tomohiko Mitani
Kyoto University
15:56-16:09(MTT16-E-3) High Efficient Microwave Heating System with GaN-HEMT Power Amplifier(o)Masakazu Takahashi
Ryukoku University
16:09-16:22(MTT16-E-4) Study on a 5.8GHz Power-Variable Phase-Controlled Magnetron(o)Bo Yang, Naoki Shinohara
Kyoto University

Break time 16:22-16:30
Session MTT16-F 16:30- Chair:
16:30-16:43(MTT16-F-1) Improvement of Passband Characteristics Based on Physical Mechanism in GA-designed
UWB Filter(o)Yuta Takeuchi, Mikio Tsuji, Hiroyuki Deguchi
Doshisha University4

16:43-16:56(MTT16-F-2) Frequency Chirp Modulation by Electro-Optic Modulator Integrated with Microwave RatRace Circuit(o)Naoki Maeda, Katsuyuki YAMAMOTO, Tadashi KAWAI, Akira ENOKIHARA, Naokatsu YAMAMOTO,
Tetsuya KAWANISHI
University of Hyogo
16:56-17:09(MTT16-F-3) Design Method of Attenuation Poles for Electromagnetically-coupled Half-Wavelength
Resonator Filters(o)Ayaka Shimizu
Ryukoku University
17:09-17:22(MTT16-F-4) Compensation of Third-Order Intermodulation Distortion of Electro-Optic Modulator by
Using Frequency Chirp Modulation(o)Kosuke Takase, Sachiko Maeda , Tadashi Kawai, Akira Enokihara, Naokatsu Yamamoto, Tetsuya Kawanishi
University of Hyogo

Banquet 18:00-20:00

5

(MTT16-A-1) Title: Demonstration of Circularly-Polarized Leaky Wave Anttena Based on PseudoTraveling Wave Reasonance
Author: (o)Kubo Yuki, Keisuke Ninomiya, Tetsuya Ueda, Andrey Porokhnyuk, Tatsuo ItohAffiliation: Kyoto Institute of Technology
Abstract: A circularly-polarized leaky-wave radiation from metamaterial-inspired antenna based on
pseudo-traveling wave resonance was demonstrated for the first time. The resonant structure wasshort-ended transmission line resonator and composed of a phase-nonreciprocal composite right/left
handed transmission line fabricated on the circumference of a normally magnetized polycrystalline
yttrium iron garnet disc. At both ends of the phase-nonreciprocal CRLH transmission line section
there are two different reflectors, and the longer reflector was directly connected to a feed line for
impedance matching. The resonator operates as zeroth-order resonator if there is no DC magnetic
field and the gradient of the phase of field profiles along the transmission line of this structure wasappropriately selected by tuning the dc magnetic field externally applied to the ferrite disc so that thephase difference for one circulation corresponds to 360 deg when an appropriate DC magnetic field
is applied. Measured results clearly showed that the radiation from the Antenna is circularlyPolarized and rotation direction of the circular polarization was successfully switched by changing
the direction of the applied dc magnetic field.
Keywords: Electromagnetic metamaterials, transmission lines, leaky wave antennas(MTT16-A-2) Title: Study on Re-radiation Characteristics of Rectenna Harmonics for a Harmonics
Based Retrodirective System
Author: (o)Shogo Kawashima
Affiliation: Kyoto University
Abstract: A harmonics-based retrodirective system (HBRS) is proposed for microwave powertransmission to an airplane for weight saving. In the HBRS, re-radiation of rectenna harmonics is
adopted for the pilot signal. It is necessary for actualizing the HBRS to evaluate harmonic reradiation from rectennas. In this presentation, we fabricated a rectenna which are on a thin andlightweight substrate, and conducted simulations and experiments of harmonic re-radiation patterns.
In electromagnetic simulations, we obtained radiation patterns of the 2nd and the 3rd harmonics
which were similar to the theoretical patterns of a dipole antenna and a dipole antenna. From theexperiments, the 2nd and the 3rd harmonic re-radiation patterns were measured, and they wereagreed with the simulations. Re-radiation of array of two rectenna was also measured, and the nullpoints were increased from the patterns of a single rectenna. Calculating array factor in theassumption that two rectenna re-radiates in same phase, we obtained calculation patterns. They werein consistent with the measurement results. This showed that two rectennas re-radiates in same phasein experiment. Comparing a past study and our results, we examined with the realization of HBRSI.
It is considered to be a problem that arraying rectennas caused the increase of null points.
Keywords: Microwave Power Transmission, Rectenna, Harmonics, Retrodirective

6

(MTT16-A-3) Title: Multistep rectangular horn loading grooves with elliptical beam for dualpolarization
Author: (o)Reiko Omi, Mikio Tsuji, Hiroyuki Deguchi
Affiliation: Doshisha University
Abstract: An elliptical-shaped beam antenna is required for efficient coverage of a specified region.
Such a beam has been realized by using reflectors with elliptical shape and primary feeds withdesired edge illumination level. The elliptical-shaped horns are useful for reduction of a spill-overloss and a gain loss due to the illumination distribution. This paper proposes a new rectangular horn
for orthogonal polarized elliptical beams. This consists of two sectoral horns, of which sidewalls
have grooves its design is performed by optimization based on the mode-matching method. As adesign example, we present a horn with - 10 dB beam widths of 33° × 100° at 10 GHz. Effectivenessof the designed horn is verified numerically and experimentally.
Keywords: elliptical beam, orthogonal dual polarizations, groove, rectangular horn

(MTT16-A-4) Title: Studies on a Fabric Feed Line Sewn to a Flexible Slot Antenna
Author: (o)Yuto Ishii
Affiliation: Graduate School of Science and Technology, Kyoto Institute of Technology
Abstract: A flexible textile antenna has been fabricated using a polyester fabric as a substrate of thefeed line to the antenna and studied in bending cases. The antenna is a cavity-backed slot antenna(CBSA) made of conductive textiles. The substrate of the feed line is also a textile sheet rather thanconventional material in order to make the antenna more flexible. Moreover, the feed line is fixed bysewing directly to the CBSA to prevent a gap between the feed line and the antenna. The antenna
performances in 2.4-GHz band have been measured depending on the radius of curvature of theantenna and compared with those fixing the feed line by adhesive tape in the previous study. The
results revealed that the -10 dB bandwidth in the sewing case is wider than that by the previous case.
Thus, we suggest that the antenna characteristics can be improved by the reduction of unnecessary
deformation of the feed line and the antenna.
Keywords: Conductive textile, microwave, cavity-backed slot antenna, feed line, polyester fabric,
flexibility(MTT16-A-5) Title: Linear-to-circular polarization reflectarray with arbitrarily shaped elements
Author: (o)Hiroki Yamada, Hiroyuki Deguchi, Mikio Tsuji
Affiliation: Doshisha University
Abstract: This paper proposes arbitrary shaped elements for linear-to-circular polarizer forreflectarray. We optimized the resonant elements with orthogonal two axial symmetry by the genetic
algorithm (GA). Moreover, the effectiveness of the proposed elements is verified by discussing
radiation characteristics of a fabricated offset reflectarray numerically and experimentally.
Keywords: reflectarray, genetic algorithm, arbitrary shape

7

(MTT16-B-1) Title: Study on Operational-Amplifier-Based Negative Impedance Converters to
Realize non-Foster Elements
Author: (o)Shoji Yamanaka, Yasushi Horii
Affiliation: Graduate School of Informatics, Kansai University
Abstract: With recent progress of the Things of Internet (IoT), wireless communication tools should
be designed more compact and highly functional. However, electrically small antennas cannot
provide broadband operation due to their high Q-factor. Therefore, innovative technologies are
required to meet the demand. In such a situation, negative capacitance and negative inductance arecollecting a lot of attentions recently. These negative elements are realized by using negative
impedance converters (NIC) that make capacitors or inductors sign-reversed. These elements arecalled Non-Foster elements for convenient. Non-Foster matching is expected to improve theperformance of electrically small antennas by canceling antenna reactance in a wide frequency range.
In this presentation, I focus on OP-amp-based NICs. Comparing with BJT-based NICs, the numberof circuit elements used for the NIC circuit is reduced drastically, leading to simplifying the circuit
configuration. However, we have experienced serious errors between simulations and measurements,that is, in some cases, non-Foster behavior was not obtained as theory. In this presentation, I verify
following three points to realize Non-Foster characteristic. (1) Look for conditions to realize NonFoster characteristics, (2) analyze the influence of parasitic inductance induced on the PCB byutilizing ADS and Momentum simulations, and (3) fabricate smaller NIC circuits in order to reduceparasitic inductance. Subsequently, I fabricate a new model and compare its performance with theconventional one.
Keywords:(MTT16-B-2) Title: Equivalent Circuit Model of Planar Meta-atoms with Retarded Electromagnetic
Coupling
Author: (o)Ryoma Nakata, Tohlu Matsushima, Takashi Hisakado, Osami Wada
Affiliation: Kyoto University
Abstract: Metamaterials are artificial structures composed of meta-atoms made from conductors or
dielectrics and show electromagnetic phenomena which cannot happen in natural materials. It isnecessary to know the electromagnetic behavior of meta-atoms to analyze the electromagnetic
phenomena that the whole metamaterials show. For analysis of the metamaterials, electromagnetic
field analysis is used frequently. However, the calculations need a lot of time for the analysis.
Therefore as more systematic one, analysis using equivalent circuit models of metamaterials has
been considered. In those examinations, the retardation of the electromagnetic field is shown to be an
important factor in equivalent circuit models. Then, our purpose is to observe the influence of theretardation of the electromagnetic field in the metamaterials by experiments. To experiment easily
we handle planar meta-atoms having the structure of connected thin conductor disks by thin
conductor lines. We build the equivalent circuit model of the planar meta-atoms including retardationand compare it with the experiment and evaluate the influence of the retardation of theelectromagnetic field. When we consider retardation, the magnitude relation of the resonant evenmode and odd mode frequencies of coupled two planar meta-atoms varies by the distance between
them. We express this phenomenon by equivalent circuit model including retardation anddemonstrate it by experiment.
Keywords: equivalent circuit model, retarded electromagnetic coupling, resonant frequency

8

(MTT16-B-3) Title: Study on Linvill’s Negative Impedance Converters for Generation of Pure NonFoster Reactance
Author: (o)Kenichi Matsumoto, Yasushi Horii
Affiliation: Graduate School of Informatics, Kansai University
Abstract: In recent years, miniaturized high performance antennas for wireless communications
have been studied intensively. Among various new technologies, we have focused on non-Foster
matching including negative capacitors and negative inductors. Such a non-Foster element isgenerated by a negative impedance converter (NIC). In this presentation, I overview the principle
and typical performance of Linvill's NIC, and then, point out a serious problem that ""the NIC
generates an undesired resistance by itself, and most of the input RF power is absorbed by the NIC
itself, instead of being radiated from the antenna"". To solve this problem, I design a new NIC whose
undesired resistance is self-canceled by a negative resistance generated by the same NIC circuit. This
strategy has a great advantage in terms of DC power consumption, that is, additional DC power
consumption can be ignored even if negative resistance is generated together with the negative
capacitance. In the experimental demonstration, measured DC power consumption of the NICs withand without self-cancellation mechanism is 10 mW for both cased at 2.2V biasing and 20mW at
3.5V biasing for the input RF frequency of 300 MHz. Based on this idea, a pure non-Foster reactancewill be realized.
Keywords:(MTT16-B-4) Title: Considerations for Loss Mechanism and Improvement of Artificial DielectricResonator
Author: (o)Yulin Song, Toshio Ishizaki
Affiliation: Ryukoku University
Abstract: Due to the recent increase of data traffic, much more cellular base stations are required to
be installed. Miniaturization and cost reduction of base station filter is strongly expected. In thisstudy, a novel filter was developed by using artificial dielectric with high dielectric constant andanisotropy. To realize high unloaded Q, loss caused by circulating current should be reduced,
because it does not contribute to dielectric constant. Dumbbell-shaped metal strips were investigatedto reduce the circulating current. By optimizing number of tracks and gap between tracks, magnetic
flux became easily go through the body of artificial dielectric and loss caused by circulating current
was decreased by 15%.
Keywords: Artificial dielectric, Microwave filter, Dumbbell-type strip, Unloaded Q

9(MTT16-B-5) Title: Study on Equivalent Circuit Models for Helmholtz Resonators for Design of
Future Acoustic Metamaterials
Author: (o)Yuki Utoku, Yasushi Horii
Affiliation: Graduate School of Informatics, Kansai University
Abstract: Similar to the RF distributed constant circuits, acoustic systems can also be expressed byan equivalent circuit model with inductors ""L"" and capacitors ""C"" based on acoustic parameterssuch as air densities, sound velocities, and volumes of cavities. This transmission-line-theory-likeapproach is quite useful to understand and design complicated acoustic systems. Prof. Sam Hyeon
Lee, for instance, proposed equivalent circuit models of acoustic metamaterials and demonstrated
successfully. In this presentation, I explain the mechanism of Helmholtz resonators composed of acavity and a narrow pipe portion (a neck) first, and then, give an equivalent circuit model expressedby a series connection of a capacitor and an inductor, which correspond to the cavity and the neck of
the resonator, respectively. Following that, analytically estimated resonant frequency of the resonatoris compared with full-wave acoustic simulations by Comsol Multiphysics 5.1. When the cavity
length is varied from 30 mm to 80 mm, both analytical and simulated results show good agreementswith each other within an acceptable range of errors of about 5% in a frequency range from 0 to 600
Hz. I believe that this transmission-line-theory-like approach will be a great help for designing anddeveloping attractive future acoustic metamaterials.
Keywords:(MTT16-C-1) Title: Excitation Circuit with Variable Capacitors for Resonator-Coupled WPT
SystemAuthor: (o)Takehiro Toi1, Tetsuya Ishida2, Toshio Ishizaki1
Affiliation: 1Ryukoku University, 2Wave Technology Inc.
Abstract: The objective of this study is to develop a variable impedance matching circuit forrealizing a stable transmission, while transmission distance is varied. The matching circuit isconstructed by variable capacitors, comprising SPST switches using PIN diodes and bank of fixedcapacitors. It was confirmed that a switched excitation circuit with variable capacitors showed higher
transmission efficiency than that of fixed system in the simulation. Further, although there was a
suitable distance for the case, where only Tx-side was matched, a better efficiency at an arbitrary
desired distance could be achieved by appropriately tuning Rx-side matching simultaneously.
Keywords: Wireless power transfer, Matching circuit, Variable capacitor, PIN diode10

(MTT16-C-2) Title: Study on a Rectifier for Microwave Power Transfer with Intermittent Input
SignalAuthor: (o)Takashi Hirakawa, Naoki Shinohara
Affiliation: Research Institute for Sustainable Humanosphere, Kyoto University
Abstract: High-efficiency rectifier circuit is required for microwave power transfer. In this paper,
we studied on the operation of a rectifier circuit with intermittent input signal. Intermittent signal isuseful signal for coexistence with communication and has high peak-to-average power ratio. We can
expect an improvement of RF-DC conversion efficiency by using intermittent input signal. But theoutput of a rectifier circuit with intermittent input becomes pulse wave or DC whose ripple content isvery high. Frequently, such outputs are not useful and can damage on machines. However, theoperation of a rectifier circuit after the input stopped is not discussed enough. Therefore, we analyzed
the operation of a rectifier circuit by considering the time constants. As a result of this study, we
revealed that the operation of a rectifier circuit can be analyzed by using time constants in someconditions. We also calculated RF-DC conversion efficiency and ripple content by using such a
condition.
Keywords: Rectifier, Intermittent, High peak to average, power ratio(MTT16-C-3) Title: Switchable Power Receiving Unit for Mobile WPT System Providing Power toMultiple Vehicles
Author: (o)Kohei Yamamoto
Affiliation: Ryukoku University
Abstract: For wireless power transfer system providing power for moving electric vehicles, it might
be necessary for providing power for multiple vehicles. For this purpose, the authors are developing
a new receiving unit, which allows to receive power in an assigned time slot by switching.
Resonators of receiving unit are switched to perform selective power receiving. For this unit, it isimportant to avoid an additional loss due to the switch circuit and keep the efficiency of the system.
In this study, in order to achieve low loss and keep efficiency, the switching circuit is designed by
optimizing circuit pattern of transistor switch based on simulated performances of multiple power
supply system. As a result, it was confirmed by experiment that power was successfully supplied to
two toy cars.
Keywords: Wireless power transfer, Multiple power supply, Switchable receiving unit
(MTT16-C-4) Title: Multiple-Input Multiple-Output Dynamic Charging Using Multiple Parallel
Line Feeders
Author: (o)Brou William-Fabrice, Duong Quang Thang, Minoru Okada
Affiliation: Graduate School of Information, Nara Institute of Science and Technology
Abstract: This paper proposes a multiple-input multiple-output dynamic charging system for electricvehicles (EVs) using more than one parallel line feeders and pick-ups. In a charging system using
one single feeder, because the feeder length is not negligible compared to the wavelength, the electric
current along the feeder follows a standing wave pattern, resulting in a fluctuation in output power
when the EV moves. Therefore, the proposed system exploits pattern diversity by using multiple
feeders with different current standing wave patterns to stabilize the output power. A multiplexing
effect is also utilized to improve the output power in order to satisfy the requirement for high output
power while keeping the input power low for safety reasons in each feeder. The effectiveness of the
proposed system is verified by theoretical analysis and experiments on a system of three feeders andthree pick-ups operating at 13.56 MHz.
Keywords: Multiple-input multiple-output, dynamic charging, parallel line feeder, diversity,
multiplexing, standing wave
11

(MTT16-C-5) Title: Power Transfer Experiment of Magnetically Coupled WPT System for EVs
through Tires
Author: (o)Yuki Kawazoe, Yangjun Zhang, Ikuo Awai
Affiliation: Ryukoku University
Abstract: In recent years, applications using wireless power supply system are widely studied.
However, for electric vehicle, there are still many problems to be solved. For example, charge time is
too long, and it must be shorted. The distance that can be run by one charge must be long enough etc.
In this study, we try to develop a system to realize a wireless power charge by using a magnetic field
coupled resonator system via the tire. The power is transmitted from the assumed coil resonator
which is embedded in the road, and received by two resonators via the tire (road-wheel-body). We
have made many demonstration experiments and investigated the efficiency to transfer the power.
With respect to the power transmission resonator, we compared two kinds of spiral resonators withdifferent structures. Also to obtain an impedance matching, we calculate the input impedance using
the equivalent circuit, and compare it with the measured value. I also made a system using a toy car
which is four-wheel drive tool kit. We check our research results with this toy system. It is shown the
results are good.
Keywords: WPT, EV, Magnetic field coupling(MTT16-D-1) Title: Proposal and basic study of a transparent water shield for the magneticallycoupled WPT system -Toward resolution of EMC problemsAuthor: (o)Kentaro Kawabe
Affiliation: Ryukoku University
Abstract: We propose here a transparent electromagnetic shield using tap water. We have obtained a
big shield effect for the leakage electric field from the WPT system by using the reflection due
impedance mismatching between the water sheet and the free space where there is a wave source. In
addition, the loss to a system is quite small by its selective shield effect that hardly influences themagnetic field used for power transfer. Aiming that this shielding method could be adopted widely,
we will show the simulation and measurement of the effect of the present selective shield method
which uses water for the EMC solution to a WPT system for the robot fish which our study group is
now developing.
Keywords: Wireless power transfer System, Tap water, Electromagnetic shield, EMC, Spiralresonator with capacitor, water shield(MTT16-D-2) Title: Effect of Bush Growth on Radio Wave Propagation in 920 MHz Band
Author: (o)Ryosuke Yoshimura
Affiliation: Graduate School of Science and Technology, Kyoto Institute of Technology
Abstract: The change of the radio wave propagation loss in 920-MHz band was examined as bushes
in a farm grew higher. Received Signal Strength Indicator (RSSI) was measured as a function of the
distance between the transmitting antenna (Tx) and the receiving antenna (Rx) in a 50 x 50 m
mulberry field. Tx and Rx were placed at a height of 1.5 m. Moreover, the horizontal and verticalpolarizations were measured. The results revealed that the path loss increased in both horizontal andvertical polarizations as bushes grew up and that the horizontal polarization could be less affected bybushes than the vertical polarization.
Keywords: Radio wave propagation, path loss, 920-MHz, wireless sensor network, bushes

12

(MTT16-D-3) Title: Study on Conductive Effects of Water for a WPT system Applied for Robot
Fish
Author: (o)Tatuya Hiraiwa
Affiliation: Ryukoku University
Abstract: A coupled-resonator-type wireless power transfer system applied for robot fish in
aquarium is investigated. For the system, there is a problem that the system does not work welldepending on the sites, where the tap water is acquired. Thus, dependency on conductivity of various
tap water is studied. Also, a solution for this problem is considered. It was confirmed that theresonance frequency did not change by conductivity of water. On the other hand, unloaded Q was
decreased and loss was increased by conductivity of water. However, the conductivity becomeslarger, the influence becomes smaller, at least in the conductivity variations of tap water. To suppress
the influence, large capacitor is connected in parallel to the resonator so that electric energy is
confined in the capacitor. Unloaded Q became not affected by conductivity. As a result, a resonator
which was not influenced by conductivity was developed successfully.
Keywords: Coupled-resonator WPT System, Conductivity, Underwater feeding(MTT16-D-4) Title: Signal Interference Analysis Model In Near-Field Coupling Communication
Author: (o)Ryo Takeuchi
Affiliation: Graduate School of Science and Technology, Kyoto Institute of Technology
Abstract: Near-field coupling communication (NFCC) is a technology that uses the surface of thehuman body as a transmission path. To suppress the radiation signal from the human body, NFCC
devices use a carrier frequency of less than 10 MHz. Because the radiation signal has the potential todisturb the other NFCC links, the radiation signal from other devices needs to be suppressed toensure stable NFCC links. This study describes our investigation of the interfering mechanism in
NFCC systems to put the systems into practical use, such as at a ticket gate in the train station. We
measured interference signal losses depending on the distance between two phantoms, regarded as
human bodies. Based on the experimental and simulated results, an equivalent circuit of the signal
interference was proposed. From the interference analytical model, we identified the capacitance thatcaused the interference problem and found that weakening the effects of this capacitance wasimportant to achieve a stable NFCC link.
Keywords: Near-field coupling communication, Electrically isolated measurement, Path/Signal loss,
interference problem.
(MTT16-D-5) Title: Miniaturized Amplifier Module for Millimeter-wave Wireless Communication
and Power Transfer System
Author: (o)Hayato Matsuo
Affiliation: Ryukoku University
Abstract: In Millimeter-wave Wireless Communication and Power Transfer (WiCoPT) system,
energy is sent from control terminal to battery-less sensors wirelessly. Then, sensors send backinformation to control terminal by using received energy. Objective of this study is to miniaturize thetransmitting amplifier module in the control system. Because the control system adopt an active
integrated antenna to make a spot beam, space between adjacent antenna elements is severely limited
to avoid grating lobes. Thus, miniaturized amplifier modules are required to being installed forrespective antenna elements one by one on the back-side of antenna substrate. The amplifier module
was miniaturized, for example, by shrinking bias circuit using the curved lines for RF choke circuit.
Almost the same performance with that of conventional circuit was obtained even for theminiaturized module.
Keywords:
13

(MTT16-E-1) Title: A Small-Sized Oscillator Using Dielectric Resonator for Microwave Surgical
Instruments
Author: (o)Yosuke Yokoyama
Affiliation: Ryukoku University
Abstract: Microwave surgical instruments heat cells by irradiating microwaves, and stop bleedingby congealing cells. Existing microwave signal sources for portable surgical instrument are still large
and heavy. Operators often feel difficulty due to poor operability. Thus, it is necessary to reduce thesize of signal source, especially the sizes of power amplifier and oscillator. To reduce the size, theauthors developed compact GaN power amplifier by using LTCC technology and small-sized
oscillator. In this report, the development of small-sized oscillator using dielectric resonator will be
explained. Frequency stability for supply voltage and temperature satisfied the target values by using
dielectric coaxial resonator.
Keywords:(MTT16-E-2) Title: Study on Characteristics of a Single-Mode Resonator for Microwave Heating
Author: (o)Daichi Nishio, Tomohiko Mitani
Affiliation: Research Institute of Sustainable Humanosphere, Kyoto University
Abstract: Recently, single-mode resonators are used for chemical experiments assisted by
microwave heating. For easy designing equipment for microwave heating, we need relations of the Q
factor and impedance of a single-mode resonator to an iris width and a heating sample temperature.
However their relations are unclear. Therefore we investigate relations with simulations andexperiments. We designed a resonator to heat pure water as a sample using a simulator, HFSS. The
resonator length was 220 mm. In this condition, the antinode position of electric field matched thecenter of the sample. As a result, the relation between the Q factor and the sample temperature had apositive correlation. We find that the tendency was explainable using the sample dielectric tangent.
Furthermore we find that the relations of the impedance of the resonator to the sample temperatureand the iris width also was explainable using the sample relative permittivity and the iris impedance
formula.
Keywords: Microwave Heating, Single-Mode, Resonator(MTT16-E-3) Title: High Efficient Microwave Heating System with GaN-HEMT Power Amplifier
Author: (o)Masakazu Takahashi
Affiliation: Ryukoku University
Abstract: So far, magnetron is widely used for microwave heating, such as microwave oven andbiomass material production. However, magnetron has many demerits. For example, it has short life
time, large size and the signal is very noisy. However, recently, a new excellent solid-state device,
Gallium Nitride (GaN) transistor, which has a high power capability in microwave range, has beendeveloped. It comes a possibility that magnetrons are replaced by GaN transistors. Frequency, phaseand power of generated microwave can easily be controlled for solid-state amplifier. In this report,
the effectiveness of heating by controlling these parameters was investigated. High efficiency was
obtained by optimizing these parameters.
Keywords: GaN power amplifier, Microwave heating system, High efficiency

14

(MTT16-E-4) Title: Study on a 5.8GHz Power-Variable Phase-Controlled Magnetron
Author: (o)Bo Yang, Naoki Shinohara
Affiliation: Graduate Research Institute for Sustainable Humanosphere, Kyoto University
Abstract: Power -Variable Phase- Controlled Magnetron (PVPCM) has been developed for several
years by our research group. In 2000, the first PCM has been developed which utilizes injection
locking method and anode current control phase locked loop method. In 2011, our research group
has developed a new method which controls the phase of 2.45GHz magnetron output by phase shifter
without anode current control phase locked loop. The new method needn’t special frequency
characteristics of the magnetron which was necessary to be required on the old method. Therefore
the new method could control the power of magnetron by controlling anode current of magnetron.
The old method control the power by controlling a magnetic field of magnetron which made the
PVPCM system more complex. The objective of the present study is to develop a 5.8GHz
microwave power transmission system for airplane. We suggest a PVPCM array antenna for the
microwave source of the transmission system by applying the new method. First, we confirmed
feasibility of the PVPCM and succeeded in controlling the phase with digital control circuit.
However the digital control circuit was cost nearly 150ms to lock the phase of magnetron output.
Finally, we made an analog phase control circuit whose response time was less than 1ms, fasterenough for beam forming of array antenna.
Keywords:(MTT16-F-1) Title: Improvement of Passband Characteristics Based on Physical Mechanism in
GA-designed UWB Filter
Author: (o)Yuta Takeuchi, Mikio Tsuji, Hiroyuki Deguchi
Affiliation: Doshisha University
Abstract: A compact ultra-wideband (UWB) filter with defected ground structure (DGS) ispresented. We previously proposed the UWB filter consisting of genetic algorithm (GA)-optimized
conductor patch and slot shapes. Although the optimized filter had the desired passbands in the low
and the high frequency ranges (3.4dd-4.8GHz, and 7. 25 and 10.25GHz), the return losses there were
not so low (about 10B). Therefore, we first clarified resonant mechanism of the UWB filter
optimized by the GA. Then, new conductor patch and DGS shapes based on this resonant mechanism
are proposed to improve characteristics of the dual-band filter. As a result the return losses in two
pass-band regions are suppressed less than 20dB.
Keywords: UWB, genetic algorithm, dualband, DGS

15

(MTT16-F-2) Title: Frequency Chirp Modulation by Electro-Optic Modulator Integrated with
Microwave Rat-Race Circuit
Author: (o)Naoki Maeda1, Katsuyuki Yamamoto1, Tadashi Kawai1, Akira Enokihara1, Naokatsu
Yamamoto2, Tetsuya Kawanishi2, 3Affiliation: 1Graduate School of Engineering, University of Hyogo, 2National Institute ofInformation and Communications Technology, 3Faculty of Science and Engineering, Waseda
University
Abstract: A Mach-Zehnder electro-optic modulator (MZM) generates intensity-modulated light withfrequency chirp by introducing asymmetricity in the interference. The frequency chirp modulation isapplicable to the flat optical comb signal generation or the pre-chirp modulation. Here, we show thefrequency chirp modulator using a rat-race circuit (RR) which operates as a 180-degree hybrid of anasymmetric power split for preparing two modulation signals with different power. The RR is
integrated with the MZM on the same substrate to directly feed the two signals to the modulationelectrodes. Thereby, frequency chirp modulation is realized by a compact and single-chip
configuration with single-input operation. The RR of a power split ratio of 4.5:1 was designed on a
LiNbO3 substrate at 10 GHz using the parallel ring circuit structure, which is effective for line
impedance control, and was directly connected to the modulation electrodes of the MZM. The
modulator was fabricated and the modulation operation at 1550 nm wavelength was confirmed byobserving output light spectra. Moreover, frequency chirping in the modulated light was directly
measured by using the chromatic dispersion of optical fibers of which length was from 0 to 80 km.
The chirp parameter of 0.47 was obtained from the fiber length where power penalty in the detected
microwave signals was observed.
Keywords: frequency chirp, electro-optic modulator, rat-race circuit, LiNbO3, chromatic dispersion(MTT16-F-3) Title: Design Method of Attenuation Poles for Electromagnetically-coupled HalfWavelength Resonator Filters
Author: (o)Ayaka Shimizu
Affiliation: Ryukoku University
Abstract: In recent years, data traffic is increasing with the spread of smart-phones. So, it is required
to install much more base stations. Thus, size and cost reductions of base station filter are strongly
requested. By providing the attenuation pole near the pass band, high-selectivity with large
attenuation outside the pass band can be obtained. In this study, design theory of attenuation poles
for half-wavelength resonator filter is investigated. It was confirmed that the attenuation polefrequency could be designed by simplifying the circuit transfer functions expressed by equations. As
a result, the filter was able to be designed by analytically using these formulae. A half-wavelength
electromagnetically-coupled resonator filter was designed successfully.
Keywords:

16

(MTT16-F-4) Title: Compensation of Third-Order Intermodulation Distortion of Electro-Optic
Modulator by Using Frequency Chirp Modulation
Author: (o)Kosuke Takase1, Sachiko Maeda2, Tadashi Kawai1, Akira Enokihara1, Naokatsu
Yamamoto3, Tetsuya Kawanishi4
Affiliation: 1Graduate School of Engineering, University of Hyogo, 2School of Engineering,
University of Hyogo, 3National Institute of Information and Communications Technology, 4Facultyof Science and Engineering, Waseda University
Abstract: Mach-Zehnder electro-optic modulator (MZM) has nonlinearity in properties of themodulation responses. The third-order intermodulation distortion (IMD3), which is induced near thesignal frequency, may seriously degrade performance of signal transmission with analogue light
modulation, such as radio on fiber systems. In this report, we propose a novel method to opticallycompensate the IMD3 components in detected electric signals, where a dual parallel Mach-Zehnder
modulator (DPMZM) that consists of two MZMs inducing frequency chirping of opposite signs witheach other is used. This compensation operation does not depend on modulation signal frequency.
The IMD3 suppression of the proposed modulator was estimated by numerical calculations. Whenthe output light modulated by a two-tone electric signal is detected by a photo-detector, the power
ratio of a signal to the IMD3 in the detected output was calculated as a function of modulation index.
In the case of using DPMZM that consisting of two MZMs with ±0.5 chirp parameters, respectively,
more than 30dB IMD3 suppression compared with a conventional MZM was obtained at themodulation index of 0〜0.2 πrad. Moreover, we fabricated the DPMZM on the LiNbO3 substrate.
The operation of the IMD3 suppression was confirmed by the experiment.
Keywords: electro-optic modulator, nonlinearity, distortion, third-order intermodulation, frequency
chirp17