Hideki Kamitsuna

Ultrahigh-speed InP/InGaAs DHPTs for OEMMICs

This paper presents an ultrahigh-speed InP/InGaAs double-heterostructure phototransistor (DHPT) with a record optical gain cutoff frequency of 82 GHz. This excellent performance originates from the double-heterostructures compatibility with high-performance double-heterostructure bipolar transistor (DHBT) and a new self-aligned process. To demonstrate the excellent performance of the DHPT, two kinds of optoelectronic MMICs (OEMMICs) were designed and fabricated. One is a 40-GHz-band DHPT/DHBT photoreceiver that shows the DHPTs ability to be simultaneously integrated with a high-performance DHBT. The 40 GHz operation frequency is also the highest reported for monolithically integrated HPT/HBT photoreceivers. The other is a direct optical injection-locked oscillator that can extract an electrical clock signal from optical data streams. The OEMMICs are promising for compact and low-power-consumption optical receivers on an InP platform for millimeter-wave photonics and ultrahigh-speed optical communication systems.

60-GHz bidirectional radio-on-fiber links based on InP-InGaAs HPT optoelectronic mixers

We demonstrate 60-GHz band bidirectional radio-on-fiber (RoF) links based on InP-InGaAs heterojunction phototransistor (HPT) optoelectronic mixers. They employ remote up/down conversion scheme with optical local oscillator signals distributed from the central office and intermediate frequency (IF) fiber transmission for both up- and down-links. Since frequency up/down conversions and photodetection are carried out by a single HPT optoelectronic mixer, base station architecture is greatly simplified. In order to validate its feasibility, both up- and down-link RoF transmissions of 16 quadrature amplitude modulator data are successfully demonstrated at 60-GHz band using 1.25-GHz IF for down-link and 2.0-GHz IF for up-link.

A novel high-frequency quasi-SOI power MOSFET for multi-gigahertz applications

We have fabricated a high-efficiency quasi-SOI power MOSFET for multi-gigahertz applications. The device was formed by reversed silicon wafer direct bonding which enables easy use of a high-resistivity substrate. The breakdown voltage of the quasi-SOI power MOSFET is more than twice that of a conventional SOI power MOSFET. Fmax of the quasi-SOI power MOSFET is 11.0 GHz, about 15% higher than that of the SOI power MOSFET. The fabricated device has the excellent power added efficiency of 68% at a 2 GHz under 3.6 V operation.

A 43-Gb/s clock and data recovery OEIC integrating an InP-InGaAs HPT oscillator with an HBT decision circuit

This paper presents a 43-Gb/s clock and data recovery (CDR) optoelectronic integrated circuit (OEIC) that consists of a 43-GHz heterojunction phototransistor (HPT) oscillator as an optoelectronic clock recovery circuit and a 40-Gb/s-class heterojunction bipolar transistor (HBT) decision circuit. The layer and fabrication process of the HPT and HBT are fully compatible, and the HPT has a photocoupling window in the emitter electrode for optical access from the top. When the HPT is directly illuminated, the HPT oscillator successfully extracts a 43-GHz electrical clock signal from a 43-Gb/s optical data stream by itself. The OEIC regenerates the data signal input into the HBT decision circuit by using the electrical clock signal optoelectronically extracted by the HPT oscillator. The CDR OEIC achieves error-free operation for a 2/sup 31/-1 PRBS data signal. The power dissipation of the OEIC is only 0.79 W, which is less than half that of a fully electrical 40-Gb/s-class CDR IC. This is the first successful demonstration of HPT-based OEICs integrated with HBT digital circuits operating at such a high bit rate.

Direct optical injection locking of InP/InGaAs HPT oscillator ICs for microwave photonics and 40-Gbit/s-class, optoelectronic clock recovery

Presents fully monolithically integrated 10- and 39-GHz-band InP/InGaAs heterojunction phototransistor (HPT) oscillators that can be optically injection locked by directly illuminating the HPT. When optical signals are modulated by fundamental frequencies around free-running oscillations, the 10-GHz-band HPT oscillator integrated circuit (IC) achieves an ultra-wide locking range of 1401 MHz (relative bandwidth of 13.6%), and the 39-GHz-band HPT oscillator IC achieves a wide locking range of 768 MHz, which are records among the indirect and/or direct optical injection-locked oscillators reported to date. The 10-GHz-band HPT oscillator IC also achieves very wide locking ranges of 618 and 160 MHz for third and fifth subharmonic modulated optical signal injection, respectively, which is very useful for microwave photonics applications. Optoelectronic clock recovery for optical transmission systems was tested by using the 39-GHz-band HPT oscillator IC and a planar lightwave circuit Mach-Zehnder interferometer. A 38.8-GHz electrical clock signal was successfully extracted from 38.8-Gbit/s nonreturn-to-zero optical data streams.

Ultra-wideband MMIC active power splitters with arbitrary phase relationships

Novel MMIC active power splitters, which allow arbitrary phase division over wide frequency ranges exceeding an octave in bandwidth, are proposed. An FETs inherent phase inversion properties together with phase adjustment circuits, e.g., common drain FETs followed by phase-shift transmission lines, can be successfully combined for broadband, arbitrary phase division. As an example of this technique, an MMIC active quadrature splitter has been designed and fabricated in a 1.1 mm*0.7 mm chip area. A phase error of less than 5 degrees with a magnitude imbalance of less than 1 dB has been demonstrated over a double-octave frequency range of 7.2-21.6 GHz. The MMIC active power splitter promises to make possible miniaturized, full MMIC signal processing components. >

Monolithic image rejection optoelectronic up-converters that employ the MMIC process

Very small 30-GHz-band monolithic image rejection optoelectronic up-converters that employ the high-electron-mobility-transistor (HEMT)-monolithic microwave-integrated circuit (MMIC) process are discussed. An in-phase divider and a branch-line hybrid with two HEMT optoelectronic mixers are successfully integrated in an MMIC chip area of 1.5 mm*1.1 mm. Fundamental performance results are reported, and excellent wideband performance, which comes from the well balanced operation of monolithic integrated circuits, is confirmed.<<ETX>>

Low-Cost Optoelectronic Self-Injection-Locked Oscillators

We demonstrate a new configuration for an optoelectronic self-injection-locked (SIL) oscillator, where a part of the electrical output signal is self-injected after passing through a long optical delay line for output phase-noise reduction. The SIL oscillator consists of an electrical free-running oscillator and a long optical feedback loop. For the compact and low cost configuration, the free-running oscillator is realized with an InP HPT-based monolithic oscillator and electrical-to-optical conversion is carried out by two low-speed and low-cost laser diodes. With this new configuration, we achieve more than 55-dB phase-noise reduction at 10-kHz frequency offset from the center frequency of about 10.8 GHz by injecting 8-dBm optical signals without using any high-speed optoelectronic components.

Application of semiconductor optical amplifiers to microwave signal processing

This paper proposes an application of semiconductor optical amplifiers (SOAs) to RF-to-optical and optical-to-RF convertors, microwave filters and microwave samplers. The SOA convertor can make it possible to realize a compact and cost-effective radio repeater for RF signal distribution. The SOA filtering and sampling expands application areas of fiber optics to microwave signal processing. The basic performance is experimentally investigated at microwave frequencies and good performance is obtained.<<ETX>>

Fiber optic microwave links using balanced laser harmonic generation, and balanced/image cancellation laser mixing

Three fiber optic link configurations that utilize the combination of microwave functional components and optical devices are proposed. These links can suppress undesired spurious frequencies generated by laser diode nonlinearities. One configuration is a balanced laser harmonic generation link which consists of two laser diodes, an out-of-phase divider, one or two photodiodes, an in-phase combiner and one or two fibers. The other configurations are the balanced/image cancellation laser mixing links which are composed of two laser diodes, two photodiodes, out-of-phase dividers, in-phase combiners, 90 degrees hybrid circuits and two fibers. The fundamental behavior of these configurations is discussed, and the basic performance was demonstrated at microwave frequency bands. >