A5101478328- Photonic and Optical Devices
- Advanced Photonic Communication Systems
- Semiconductor Lasers and Optical Devices
- Optical Network Technologies
- Semiconductor Quantum Structures and Devices
- Advanced Fiber Laser Technologies
- Optical Wireless Communication Technologies
- Advanced Semiconductor Detectors and Materials
- Advanced Optical Network Technologies
- Millimeter-Wave Propagation and Modeling
- Quantum Dots Synthesis And Properties
- Advanced Fiber Optic Sensors
- Nanowire Synthesis and Applications
- Silicon Nanostructures and Photoluminescence
- Photonic Crystals and Applications
- Near-Field Optical Microscopy
- Terahertz technology and applications
- Semiconductor materials and devices
- Spectroscopy and Laser Applications
- Radio Frequency Integrated Circuit Design
- Advanced Optical Sensing Technologies
- Power Line Communications and Noise
- Quantum optics and atomic interactions
- Telecommunications and Broadcasting Technologies
- Optical Coherence Tomography Applications
National Institute of Information and Communications Technology
2015-2024
National Institute of Advanced Industrial Science and Technology
2008-2023
Institute of Electrical and Electronics Engineers
2021
Chulalongkorn University
2021
LIGO Scientific Collaboration
2019
Radar (United States)
2019
Waseda University
2019
Tohoku University
2018
National Center for University Entrance Examinations
2016-2018
Japan Science and Technology Agency
2011
We propose different fronthaul systems for facilitating future mobile networks based on the seamless convergence of fiber-optic and wireless in millimeter-wave (mmWave) bands. First, a flexible high-performance system is proposed through an encapsulation radio signals onto converged fiber-mmWave system. A simultaneous transmission three over successfully demonstrated. Second, optical self-heterodyne demonstrated generation access high-frequency Third, high-spectral-efficiency multiple...
We present the design of a bias-free uni-travelling-carrier photodiode (UTC-PD) that is operational above 110 GHz, and its application to 100-GBd fixed-fiber communication 109-GHz carrier-photonic wireless for advanced optical networks. The analysis operation were explained in detail using carrier concentration photo-absorption layer collector layer. In experimental results, developed UTC-PD with back-illuminated structure exhibited wide 3-dB bandwidth over GHz at 0 V. For communications,...
In this article, we propose dual-hop network architecture capable of providing high-speed communications to trains (HSTs). The system uses a seamless fiber-millimeterwave for backhaul transmission from central station antennas on trains, and highspeed in-train Wi-Fi network. can be combined with signal processing control technologies compensate interference the Doppler effect, reduce number handovers. It realize connectivity between inside outside avoid penetration loss help organize...
We used a strain compensation technique to fabricate highly stacked InAs quantum-dot (QD) structures on InP(311)B substrates. 60 layers of QDs without degrading the crystal quality and produced structure with total QD density 4.73×1012∕cm2. then fabricated broad area laser diode 30-layer stack using conventional photolithography. The showed ground state lasing at 1.58μm threshold current 162mA. achievement is due increase in density, which result technique.
Abstract Highly‐stacked InAs quantum dots (QDs) were successfully grown on InP(311)B substrates using a novel strain‐compensation technique. The number of stacked layer was increased to 300, the density QDs reaches 2 × 10 13 /cm ; this value cannot be obtained conventional QD fabrication techniques. In highly sample, show good size uniformity with lateral and vertical ordered structure. addition, sample exhibits strong 1.55 µm photoluminescence (PL) emission at room temperature.
We designed and fabricated a 100-GHz range integrated photoreceiver with zero-bias operational uni-traveling-carrier photodiode pseudomorphic high electron mobility transistor amplifier, which performed the roles of photonic power generation RF signal generation. Using photoreceiver, data rate radio- power-over-fiber transmission through multicore fiber communication was demonstrated. Subsequently, bit error 1×10 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML"...
We demonstrate the first fiber–millimeter-wave–fiber system in 100-GHz band using a low-loss optical modulator and direct photonic down-conversion technology. The utilization of for conversion millimeter-wave signal to an significantly simplifies radio receiver because it includes only front-end modulator. In addition, by adopting technology simultaneous detection microwave band, fiber–radio subsequent digital processing can be considerably simplified. Using proposed technologies, we...
We fabricated broad-area laser diodes comprising 30-layer stacks of InAs quantum dots (QDs) by using strain compensation. The devices exhibited ground-state lasing at 1529 nm in pulsed mode with a high characteristic temperature 113 K around room (20°C-80°C). Ground-state was achieved because the QD density afforded
We report a high-data-rate two-dimensional photodetector array (2D-PDA) operated over 10 GHz for compact receiver systems in multicore fiber (MCF), few-mode (FMF), and FMF-MCF, which can be directly coupled to multiparallel beams from the MCF FMF. The 2D-PDA (pixel size of 20-30 μm, pixel number 32) were designed characterized frequency response crosstalk. In on-wafer probing test, averaged 3-dB bandwidth 11.2 19.8 measured 30-μm 20-μm pixels, respectively. direct-coupling demonstration with...
We discuss and propose millimeter-wave linear cell systems for signal distribution on railway radiocommunication between train trackside, a foreign object debris detection system airport runways using the radio-over-fiber network technology. Linear configurations based wavelength-division multiplexing (WDM) power-splitter-based networks are discussed demonstrated experimentally. A single-sideband modulation data transmission in an intermediate frequency over fiber is successfully transmitted...
We propose a flexible and high-performance fronthaul system for future mobile networks using seamless combination of fiber-optic millimeter-wave (MMW) systems. The proposed employs high-quality optical MMW signal generation at the transmitter stable self-homodyne detection receiver. In downlink direction, successful transmission intraband interband carrier aggregation (CA) long-term evolution-advanced (LTE-A) signals over is experimentally confirmed. also confirm satisfactory performance...
This paper reviews our recent research activities on seamless fiber-wireless systems for future mobile networks, including: radio-on-radio-over-fiber; signal processing-aided multiple transmission; high-capacity system; and simultaneous power- radio-over-fiber.
Mobile transport networks will play a vital role in future 5G and beyond networks. In particular, access connecting radio with core are of critical importance. They be required to support massive connectivity, super high data rates, real-time services ubiquitous environment. To attain these targets, should constructed on the basis variety technologies methods, depending application scenarios, geographic areas, deployment models. this article, we present several technologies, including analog...
We have successfully developed a zero-bias operational ultra-broadband uni-traveling-carrier photodiode (UTC-PD) with frequency bandwidth above 110 GHz using low carrier concentration of 3 × 1014 cm−3 in the collection layer.
We have developed a 100-GHz fiber-fed optical-to-radio converter for radio- and power-over-fiber transmission. A zero-bias operational high-speed photodetector (3-dB bandwidth >100 GHz) could be applied the converter, taking significant advantage of no-bias feed operation. successfully demonstrated simultaneous radio power generation from one device through bias-T circuit. pseudomorphic high electron mobility transistor amplifier allowed hybrid integrated photoreceiver to enhance O/E...
We developed a high-speed and handover-free communication network for trains (HSTs) using an ultrafast switchable wavelength-division multiplexing fiber-wireless backhaul system in the W band. successfully transmitted approximately 20-Gb/s 10-Gb/s signals over switched links downlink uplink directions, respectively. An radio-cell switching of less than 10 μs was experimentally demonstrated both directions. Moreover, possibility connecting central station to many remote radio cells evaluated,...
A linear-cell-based radio-over-fiber (LC-RoF) system is proposed and demonstrated for efficient mobile communication in high-speed trains without hard handover processes. The configuration of the LC-RoF network possible router architectures are discussed field trial test advanced systems future. Via network, 90-GHz, millimeter-wave radio access between ground a train car operated centralized manner. resulting throughput 1.5 Gbit/s achieved test, which comprised 250-Mbaud four-subcarrier...