43 research outputs found
Optical terabit transmitter and receiver based on passive polymer and InP technology for high-speed optical connectivity between datacenters
We demonstrate the hybrid integration of a multi-format tunable transmitter and a coherent optical receiver based on optical polymers and InP electronics and photonics for next generation metro and core optical networks. The transmitter comprises an array of two InP Mach-Zehnder modulators (MZMs) with 42 GHz bandwidth and two passive PolyBoards at the back- and front-end of the device. The back-end PolyBoard integrates an InP gain chip, a Bragg grating and a phase section on the polymer substrate capable of 22 nm wavelength tunability inside the C-band and optical waveguides that guide the light to the inputs of the two InP MZMs. The front-end PolyBoard provides the optical waveguides for combing the In-phase and Quadrature-phase modulated signals via an integrated thermo-optic phase shifter for applying the pi/2 phase-shift at the lower arm and a 3-dB optical coupler at the output. Two InP-double heterojunction bipolar transistor (InP-DHBT) 3-bit power digital-to-analog converters (DACs) are hybridly integrated at either side of the MZM array chip in order to drive the IQ transmitter with QPSK, 16-QAM and 64-QAM encoded signals. The coherent receiver is based on the other side on a PolyBoard, which integrates an InP gain chip and a monolithic Bragg grating for the formation of the local oscillator laser, and a monolithic 90° optical hybrid. This PolyBoard is further integrated with a 4-fold InP photodiode array chip with more than 80 GHz bandwidth and two high-speed InP-DHBT transimpedance amplifiers (TIAs) with automatic gain control. The transmitter and the receiver have been experimentally evaluated at 25Gbaud over 100 km for mQAM modulation showing bit-error-rate (BER) performance performance below FEC limit
Conception, realisation et caracterisation d'un transistor a heterojonction GaAs/GaAlAs
SIGLECNRS T 57033 / INIST-CNRS - Institut de l'Information Scientifique et TechniqueFRFranc
Non linear model of InP/GaAsSb/InP DHBT process for design of a Q-Band MMIC oscillator
This paper presents the design of a MMIC oscillator operating at a 45 GHz frequency. This circuit was made by Alcatel-Thales III-V Lab with the new InP/GaAsSb/InP DHBT submicronic technology (We=700 nm). This transistor has a 15-m-long two-finger emitter. This paper describes the complete nonlinear modeling of heterojunction bipolar transistor used in this circuit. The interest of the methodology used to design this oscillator, is to be able to choose a nonlinear operating condition of the transistor from a study in amplifier mode. The oscillator simulation and measurement results are compared
Improved External Base Resistance Extraction for Submicrometer InP/InGaAs DHBT Models
An improved direct parameter extraction method is proposed for IIIâV heterojunction bipolar transistor (HBT) external base resistance extraction from forward active -parameters. The method is formulated taking into account the current dependence of the intrinsic baseâcollector capacitance found in IIIâV HBTs with a fully depleted collector. It is shown that the real part of reduces to the external base resistance at the collector current , where is a characteristic current and is the zero-current distribution factor given as the ratio of the emitter to the collector area. The determination of the parameters and from experimental -parameters is described. The method is applied to high-speed submicrometer InP/InGaAs DHBT devices and leads to small-signal equivalent circuit models, which accurately predicts the measured -parameters as well as the maximum stable power gain/maximum available power gain in the frequency range from 40 MHz to 110 GHz