A5015753190- Optical Wireless Communication Technologies
- Telecommunications and Broadcasting Technologies
- Millimeter-Wave Propagation and Modeling
- Radio Wave Propagation Studies
- Satellite Communication Systems
- Formal Methods in Verification
- Advanced Photonic Communication Systems
- Semiconductor Lasers and Optical Devices
- Wireless Communication Networks Research
- Microwave Engineering and Waveguides
- Software Testing and Debugging Techniques
- Advanced MIMO Systems Optimization
- Logic, programming, and type systems
- Photonic and Optical Devices
- Network Traffic and Congestion Control
- Aluminum Alloy Microstructure Properties
- Radio Frequency Integrated Circuit Design
- Electromagnetic Simulation and Numerical Methods
- Geophysical Methods and Applications
- Business Process Modeling and Analysis
- Aluminum Alloys Composites Properties
- Power Line Communications and Noise
- Microwave Imaging and Scattering Analysis
- Precipitation Measurement and Analysis
- Optical Systems and Laser Technology
Panasonic (Japan)
1989-2018
Hokkaido University
2003-2017
Keio University
2015-2016
JGC (Japan)
2014
Aichi University of Technology
2006-2013
National Institute of Advanced Industrial Science and Technology
2002-2013
Molecular Sciences Institute
2013
Olympus (Japan)
2006-2011
Gifu University
2010
University of Electro-Communications
2010
The authors describe the fundamental characteristics of miniaturized hairpin resonators having parallel coupled lines and show their applications to bandpass filters receiver front-end microwave integrated circuits (MICs). A method for calculating filter coupling parameters using a general-purpose circuit simulator is presented. have suitable structure MICs, size one-half that conventional without increasing insertion losses. Trial MICs these been developed shown good such as low noise high...
The deterioration and deformation of a free-space optical beam wave-front as it propagates through the atmosphere can reduce link availability may introduce burst errors thus degrading performance system. We investigate suitability utilizing soft-computing (SC) based tools for improving (FSO) communications systems. SC are used prediction key parameters FSO Measured data collected from an experimental communication system is training testing proposed multi-layer neural network predictor...
A 300-GHz CMOS transmitter module with a WR-3.4 waveguide interface is presented. The flip-chip mounted on low-cost multilayered glass epoxy printed circuit board (PCB) and transmission-line-to-waveguide transition back-short structure built of the PCB. measured output power 3-dB bandwidth are approximately −13.5 dBm 10 GHz, respectively. wireless data rate 48 Gbit/s over 5 cm 16-QAM achieved using module.
Distributed systems are complex, being usually composed of several subsystems running in parallel. Concurrent execution and inter-process communication these prone to errors that difficult detect by traditional testing, which does not cover every possible program execution. Unlike model checking can such faults a concurrent system exploring state the system. However, most model-checking techniques require be described modeling language. Although this simplifies verification, may introduced...
A 300-GHz CMOS receiver module with a WR-3.4 waveguide interface is presented. The flip-chip mounted on low-cost multilayered glass epoxy printed circuit board (PCB). transmission-line-to-waveguide transition back-short structure built into the PCB. measured conversion gain, noise figure, and 3-dB bandwidth of are approximately −23.7 dB, 33 dB 18.4 GHz, respectively. Packaging loss estimated to be 4 from gain chip −19.5 dB. wireless data rate 20 Gbit/s 16-QAM was achieved using designed modules.
We present initial results on research and development of an optical antenna module suitable for Radio-on Free-Space Optics (RoFSO) links. This new communication system is envisaged to be effective means realizing a ubiquitous society therefore eliminating the digital divide. The RoFSO trial applying Radio Fiber (RoF) technology transmission through free space. Based next generation high-speed free-space conducted in past two years at Waseda University, we have developed with efficient laser...
Transmission of modulated RF signal using FSO communications links is receiving a lot research interest recently. We are developing new advanced DWDM RoFSO link system capable transmitting multiple signals. In this paper, we present results from analytical modeling reflecting on the design parameters to evaluate and predict its performance. The interests include atmospheric turbulence characterization parameter, C <inf xmlns:mml="http://www.w3.org/1998/Math/MathML"...
In a ubiquitous network society, universal platform is necessary to satisfy customerspsila increased demand on communication at any-time, anywhere and any-situation. Radio fiber (RoF) technologies can realize cost effective for wireless services. RoF networks also be extended radio free space optics (RoFSO) providing links heterogeneous services where it not easy or feasible install optical fiber. this paper, we present an experimental study transmission of RF signals over turbulent FSO...
We have been developing BriCA (Brain-inspired Computing Architecture), the generic software platform that can combine an arbitrary number of machine learning modules to construct higher structures such as cognitive architectures inspired by brain. discuss requirements analysis and design principles this computing platform, report its implementation, describe plans for further development.
This paper proposes a symbol synchronization method which reduces the influence of intersymbol interference (ISI) for orthogonal frequency division multiplexing (OFDM) systems. The proposed extracts timing is not disturbed by delay spread within guard interval (GI) utilizing cyclic extension. Thus, effective in reducing ISI. BER characteristics system are evaluated using computer simulation. results show that achieves almost same performance as with perfect synchronization.
A type of speech coding for asynchronous transfer mode (ATM) is described. Cell processing, which improves service quality, taken into account. Missing-cell recovery methods are discussed, and the distinctive features missing-cell used with low-bit-rate examined. An example quality obtained using techniques in ATM networks The performance levels increasing cell loss compared various methods, combination dividing coded signals cells discarding cells. Representative feasible network...
It is envisioned that the next generation of ultrahigh-speed laser communication systems will utilize compact optical antennas equipped with advanced beam tracking and effective fiber coupling mechanisms. Such be used not only for space communications but also to provide links long-distance terrestrial communications. We present design a high-speed system developed utilizing off-axis free-form surface (FFS) mirrors. describe FFS devices their contribution in realizing antennas. Furthermore,...
In this paper we present the design concept plus experimental results and evaluation of a newly developed advanced DWDM Radio-on-Free-Space Optical (RoFSO) communication system capable simultaneous transmission multiple RF signals. The RoFSO is evaluated based on performance metric parameters defined for various signals comprising different wireless services including terrestrial digital broadcasting signals, cellular 3GPP W-CDMA IEEE 802.11 WLAN etc being transmitted over link. considered...
Two novel technologies of direct conversion are introduced. One is an FSK demodulator based on a new architecture, and the other quadrature mixer for conversion. The composed relative 90 degrees phase shifters frequency multipliers suitable digital circuit implementation, it has shown wide allowance offsets local frequency. In designing IC, structural numerical optimization was carried out low power consumption. mixer, including surrounding circuits, have been integrated. order to realize...
Next generation laser communication systems will require small optical antennas and fine tracking system. Such might be applied not only to space communications such as feeder links, intersatellite links stratospheric platforms but also for long distance on the ground. We have developed a high-speed system including antenna which utilizes off-axis free form surface system, feeds back an incident angle signal detected by quadrant detector positioning mirror. In particular, available mirror...
Free-space optical communication has emerged as a competitive and viable technology for offering high data rates, improved capacity, cost-effective an easy to deploy solution providing connectivity between two points which are up few kilometers apart. In this paper we present experimental work demonstrates the practicality of next generation free-space (FSO) systems suitable short-haul, high-speed robust links. This system is placed buildings in Waseda University campus area link spanning...