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

Three fiber-optic link configurations for use in microwave transmission are proposed. Two laser diodes are used to generate balanced harmonics, and the optical power from each diode is combined and detected by photodiodes. The fundamental and odd harmonics are suppressed and even harmonics added. The balanced and image cancellation laser mixing, which utilizes a combination of microwave components and optical devices, can suppress the local and image frequencies, respectively. These configurations are experimentally investigated at microwave frequencies, and frequency suppression is successfully demonstrated     

40 Gbit/s/ch 2/spl times/2 switch IC using InP HEMTs

A low-power 2/spl times/2 switch IC using InP HEMTs as cold FETs is presented. It has a logic-level-independent interface since no signal line is grounded. The IC yields low insertion loss of 1.5-2.7 dB and high isolation of >21.2 dB below 30 GHz. When two 40 Gbit/s signals were input, error-free operation was confirmed with virtually zero power dissipation.     

Characteristics of InP–InGaAs HPT-Based Optically Injection-Locked Self-Oscillating Optoelectronic Mixers and Their Influence on Radio-Over-Fiber System Performance

A 30-GHz optically injection-locked self-oscillating optoelectronic mixer (OIL-SOM) is implemented with a high-performance InP-InGaAs heterojunction phototransistor. The subharmonic conversion efficiency and phase noise characteristics of OIL-SOM are investigated and used for analyzing OIL-SOM-based 60-GHz radio-over-fiber downlink data transmission performance. The OIL-SOM characteristics provide lower and upper boundaries for the input optical local oscillation (LO) power range within which the link performance does not significantly depend on input optical LO power     

Low-power InP-HEMT switch ICs integrating miniaturized 2/spl times/2 switches for 10-Gb/s systems

This paper presents a wideband cold-FET switch with virtually zero power dissipation. The use of InP HEMTs with a low R/sub on//spl middot/C/sub off/ product enables us to configure a DC-to-over-10-GHz single-pole double-throw (SPDT) switch without using a shunt FET. The series-FET configuration offers a logic-level-independent interface and makes possible positive control voltage operation in spite of using depletion-mode FETs. A miniaturized 2/spl times/2 switch using two SPDT switches yields an insertion loss of less than 1.16 dB and isolation of more than 21.2 dB below 10 GHz, which allows us to increase the scale of the switch in a single chip easily. The add-drop operation combining two 2/spl times/2 switches in a single chip and a 4/spl times/4 switch IC integrating four 2/spl times/2 switches are presented. The packaged ICs achieve error-free operation up to 12.5 Gb/s with either positive or negative logic-level input. Extremely fast switching of /spl sim/140 ps is also successfully demonstrated.     

Ultra-wideband MMIC active power splitters with arbitrary phaserelationships

Novel MMIC active power splitters, which allow arbitrary phase division over wide frequency ranges exceeding an octave in bandwidth, are proposed. An FET's 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° 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     

A 15-GHz monolithic low-phase-noise VCO using AlGaAs/GaAs HBTtechnology

A 15-GHz fully monolithic low-phase-noise VCO MMIC fabricated without an external tuning element using an AlGaAs/GaAs HBT technology was developed. An HBT and a variable capacitance diode or varactor were fabricated in an MMIC chip using-standard HBT IC process. A tuning range of about 600 MHz was obtained with varying control voltage from 0 to 4 V with an output power of more than -4 dBm. The low phase noise for an offset frequency of 100 kHz of -85 dBc/Hz was measured at a frequency of 15.6 GHz     

A quasi-SOI power MOSFET for radio frequency applications formed byreversed silicon wafer direct bonding

A quasi-SOI power MOSFET for radio frequency (RF) applications was fabricated by reversed silicon wafer direct bonding (RSDB). Its breakdown voltage was more than twice that of the conventional SOI power MOSFET and its other dc characteristics were almost the same. Its maximum oscillation frequency was about 15% higher than that of the conventional SOI power MOSFET. The power-added efficiency (PAE) of the quasi- SOI power MOSFET was higher than the SOI one. It showed excellent PAE of 68% at a drain bias of 3.6 V     

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.     

Ultra-wideband monolithic photoreceivers using HBT-compatible HPTswith novel base circuits, and simultaneously integrated with an HBTamplifier

This paper presents two kinds of monolithically integrated ultra-wideband photoreceivers that use HBT-compatible HPTs with novel base circuits. The HPT photoreceiver, which consists of an HPT with an inductor and series resistor base circuit, yields ultra-broadband operation with 3 dB bandwidth from 0.43-12.1 GHz and over 11 dB gain compared to a photodiode with identical quantum efficiency. The HPT/HBT photoreceiver, which consists of an HPT with an inductor at the base terminal followed by an HBT amplifier circuit, yields ultra-wideband operation from 8.5-20.5 GHz (bandwidth of 12 GHz) with over 20 dB gain. The bandwidths of these photoreceivers are state-of-the art for monolithically integrated photoreceivers using HPT/HBT structures. The proposed photoreceivers, which are based on mature MMIC technologies, offer several other remarkable features such as good design accuracy and extremely small chip size