A5005769146- Radio Frequency Integrated Circuit Design
- Photonic and Optical Devices
- Climate Change Policy and Economics
- Climate Change and Geoengineering
- Solar Thermal and Photovoltaic Systems
- Thermodynamic and Exergetic Analyses of Power and Cooling Systems
- Carbon Dioxide Capture Technologies
- Advanced Photonic Communication Systems
- Integrated Energy Systems Optimization
- Environmental Impact and Sustainability
- Microwave Engineering and Waveguides
- Semiconductor materials and devices
- Millimeter-Wave Propagation and Modeling
- GaN-based semiconductor devices and materials
- Global Energy and Sustainability Research
- Silicon Carbide Semiconductor Technologies
- Ion-surface interactions and analysis
- Climate Change Communication and Perception
- Space exploration and regulation
- Integrated Circuits and Semiconductor Failure Analysis
- Electron and X-Ray Spectroscopy Techniques
- Social Acceptance of Renewable Energy
- Solar Radiation and Photovoltaics
- Semiconductor Quantum Structures and Devices
- Terahertz technology and applications
Ritsumeikan University
2010-2024
NTT (Japan)
2001-2016
Osaka University
1989-2015
NTT Basic Research Laboratories
2002-2013
Research Institute of Innovative Technology for the Earth
2000-2004
Osaka Health Science University
1993
J-Power (Japan)
1990
A 120-GHz-band wireless link that uses millimeter-wave (MMW) photonic techniques was developed. The output power and noise characteristics of MMWs generated by converting a 125-GHz optical subcarrier signal were evaluated. It then shown the with these technologies is sufficient for 10-Gb/s data transmission. We constructed compact system, evaluated its transmission characteristics. This system achieved error-free OC-192 10-GbE signals over distance more than 200 m received below -30 dBm.
We have developed a 120-GHz-band wireless link whose maximum transmission data rate is 11.1 Gbit/s. The uses millimeter-wave monolithic integrated circuits (MMICs) for the generation of signal. MMICs were fabricated using 0.1-mum-gate InP-HEMTs and coplanar waveguides. can handle four kinds OC-192 10-Gbit Ethernet standards with without forward error correction (FEC). succeeded in error-free 10-Gbit/s signal over distance 800 m. introduction FEC into decreased minimum received power...
We have developed 120-GHz-band wireless equipment that can transmit 10-Gbit/s data signal over a distance of more than 5 km. In order to increase the output power the120-GHz-band equipment, we used millimeter-wave amplifier integrates 0.08-μm-gate-length InGaAs/InP composite-channel high-electron-mobility transistors. The becomes 16 dBm. handle rates 1 Mbit/s 11.1 Gbit/s and 10-Gbit/s-class signals with without forward error correction (FEC). conducted transmission experiments 4.8 km 5.8...
Metal Injection Molding (MIM) is characterized by its ability to accommodate complex shapes, achieve high density, offer a wide range of material choices, and facilitate mass production. Despite these advantages, there has been recognized challenge in addressing the production hollow parts. To meet market demands, we have embarked on development integrated three-dimensional shapes that were previously unattainable. We now successfully achieved MIM This paper introduces process, along with...
We measured the effects of rain attenuation on 120-GHz band wireless link during heavy rainy period (from July to September, 2008) and annual March December, 2008). The data are used as a basis for design, calculate reliability link. with V polarization was operated 400-m-long path from December 2008 in Atsugi, Japan. rate distribution Atsugi is good agreement conditional M distributions. As attenuation, coincide ITU Laws Parsons models. Cumulative distributions bit-error-rate deterioration...
Climate engineering has received increasing attention, but its discussion remained on the sidelines of mainstream climate policy. The policy relevance this previously exotic option is poised to rise because gap between temperature goals Paris Agreement and slow global mitigation efforts. It therefore crucial understand risks benefits proposed schemes, social implications choices. Assessment solar geoengineering strongly depends scenarios, previous scenarios have not reflected full range In...
The emerging narrative of the Anthropocene has created a new space for changes in global environmental change (GEC) science. On one hand, there is mounting call changing scientific practices towards solution-oriented transdisciplinary mode that can help achieve sustainability. other scientists’ desire to avoid exceeding planetary boundaries broken taboo on researching solar geoengineering, dangerous idea deliberately cooling Earth’s climate. Whilst date two features have been discussed...
Solar radiation management (SRM) is a controversial technological proposal to deliberately cool the Earth for addressing climate change. Because of great concerns over global consequences SRM deployment, an inclusive and conversation considered necessary governance SRM. However, public perception research on date has been mostly limited Global North or Western democracy. social acceptability crucial governance, such must also encompass South Eastern perspectives beyond bias. The present...
Abstract Solar geoengineering or solar radiation modification (SRM) is increasingly looming large as a potential response to human-induced climate change. However, it deeply mired in controversies surrounding environmental risks and social governance challenges. Given the high stakes uncertain characteristics of SRM, essential understand public perception. previous studies on perception have not explicitly utilized scenarios frame SRM an option future mostly been conducted Global North....
This paper describes the development of a InP-HEMT MMIC chipset for 120-GHz wireless applications. The transmitter chip includes frequency doubler carriers, an ASK modulator, RF band-pass filter, and power amplifier. receiver low-noise amplifier demodulator. A back-to-back test has shown it to be fully functional at 10-Gbit/s data rate with BER=e-12 -45.7-dBm input chip. To our knowledge, this is first report highly integrated operating 120 GHz communication.
We present a high-directivity photonic emitter with high-gain antenna and waveguide-output photodiode module (WG-PM) for extending the transmission distance of wireless link that uses 120-GHz millimeter wave. The employs uni-traveling-carrier photodiode, broad-band high electron-mobility transistor (HEMT) amplifier, planar-circuit-to-waveguide transition substrate. maximum output power WG-PM is 8 dBm at frequency 120 GHz, it has 3-dB bandwidth over 16 GHz. achieved 10-Gbit/s data...
A flexible CPW-MMIC (coplaner-waveguide monolithic microwave integrated circuit) chipset has been fabricated for 120 GHz future broadband wireless systems. The power amplifier small signal gain of 8.5 dB from 115 to 135 GHz. 1 compression point is 3 dBm at We employed a traveling wave switch configuration the ASK modulator. insertion loss less than 1.5 and on-off ratio more 13.5 For modulator-demodulator chipset, measured BER 1e/sup -10/ 10 Gbit/s PRBS 2/sup 11/-1 data -13 input RF...
This paper describes an IC technology for high-speed wireless-link systems, using photonic techniques, which provides 10 Gb/s at 120 GHz. Optical signals are converted to electrical and radiated into freespace Si-based circuitry. Both the preamp PA utilize 0.1 /spl mu/m gate InAlAs/InGaAs HEMTs with gains of 6-10 dB 8.5 dB, respectively.
The first demonstration of dual-gate AlGaN/GaN high-electron-mobility transistors (HEMTs) for high-power mixers is presented. 0.7×300 µm gate device achieved the maximum output power 19.6 dBm and upconversion gain 11 dB at 2 GHz 13 5 GHz.
The world's first practical applications of 500 kV XLPE (cross-linked polyethylene) cables took place in 1988 at the Shimogo power station Electric Power Development Co. Ltd., and Imaichi Tokyo Inc.. Research development work on had been conducted since 1982. Efforts were concentrated quality control to remove contaminants from insulation extrude very thick-walled without any defects. Insulation performance tests, including long-term aging, confirmed that terminations highly reliable with...
This paper discusses practical applications of the frequency band starting at 100 GHz—a that has yet to be fully exploited. It considers feasibility future driven by sub-terahertz and terahertz bands, examining this from two perspectives: (1) market needs standards being released meet these mainly in area communications applications, (2) advances semiconductor technologies their peripheral technologies. To discuss approaches implementing we present transmission are developing.