Agnieszka Konczykowska

Generation and Transmission of 21.4-Gbaud PDM 64-QAM Using a Novel High-Power DAC Driving a Single I/Q Modulator

We generate a single-carrier 21.4-Gbaud polarization-division-multiplexed (PDM) 64-ary quadrature-amplitude-modulated (QAM) signal (256.8-Gb/s line rate) using a single in-phase/quadrature (I/Q) optical modulator driven by 8-level electrical waveforms from a novel high-power digital-to-analog converter (DAC). We measure a required optical signal-to-noise ratio of 29.5 dB (0.1-nm reference bandwidth; 10-3 bit-error rate), 4.6-dB off the theoretical limit. Using ultra-large-area fiber, we achieve 400-km single-channel transmission. The DAC was also used to obtain excellent results with quadrature-phase-shift-keyed and 16-QAM signals at 21.4 Gbaud.

Submicron InP DHBT Technology for High-Speed High-Swing Mixed-Signal ICs

We report on the development of a submicron InP DHBT technology, optimized for the fabrication of ges50-GHz- clock mixed-signal ICs. In-depth study of device geometry and structure has allowed to get the needed performances and yield. Special attention has been paid to critical thermal behavior. Various size submicron devices have been modeled using UCSD- HBT equations. These large signal models have allowed the design of 50-GHz clocked 50 G Decision and 100 G Selector circuits. The high quality of the measured characteristics demonstrates the suitability of this technology for the various applications of interest, like 100 Gbit/s transmission.

WDM transmission at 6-Tbit/s capacity over transatlantic distance, using 42.7-Gb/s differential phase-shift keying without pulse carver

We report the transmission of a record 6 Tbit/s capacity over 6120 km distance, involving channels modulated at 42.7-Gb/s bit-rate with differential phase-shift keying (DPSK). The performance is found similar to DPSK with subsequent pulse carving, namely RZ-DPSK.

High Symbol Rate Coherent Optical Transmission Systems: 80 and 107 Gbaud

We demonstrate high speed optical transmission systems using digital coherent detection at all-electronically multiplexed symbol rates of 80 and 107 Gbaud. At 107 Gbaud, we demonstrate a single-carrier polarization division multiplexed quadrature phase shift keyed (PDM-QPSK) line rate of 428 Gb/s. At 80 Gbaud, we achieve a single-carrier line rate of 640 Gb/s using PDM 16-ary quadrature amplitude modulation (16-QAM). Using two optical subcarriers, we demonstrate a 1-Tb/s optical interface and conduct long-haul wavelength-division multiplexed (WDM) transmission on a 200-GHz grid over 3200 km of ultra-large effective area fiber.

MSI InP/InGaAs DHBT technology: beyond 40 Gbit/s circuits

We present current results obtained on IC-oriented OPTO+ InP DHBT lab technology. Transistors with 180/210 GHz F/sub t//F/sub max/, current gain of 50 and BV/sub ce0/=7V are currently fabricated with >99% fabrication yield. Uniformity measurements show a standard deviation on F/sub t/ and F/sub max/ lower than 2% and lower than 5% on all investigated parameters. In a second part DHBT-specific modelling issues are discussed. A 68 Gbit/s selector has been obtained and a 40 Gbit/s master-slave D-type flip-flop (MS-DFF) has been reproducibly fabricated with >50% functional yield using this technology.

InP DHBT technology and design methodology for high-bit-rate optical communications circuits

High-bit-rate optical communication links require high performance circuits. Electrical time division multiplex (ETDM) single channel bit-rate of 40 Gb/s is at hand, due to recent progress in both technology and design methodology. Multilevel modulation format can be envisaged for ETDM transmission. An InP double heterojunction bipolar transistor technology is presented in this paper. The methodology used and tools developed with optical communications in mind are also discussed. Fabricated circuits are reported: 40 Gb/s multiplexer and demultiplexer, a 20 Gb/s driver, a 30 Gb/s selector-driver, a 22 Gb/s decision circuit, and a decision-decoding circuit for multilevel transmissions.

Spectrally efficient long-haul transmission of 22-Tb/s using 40-Gbaud PDM-16QAM with coherent detection

We report on the transmission of 1-Tb/s clusters of channels, composed by four 50-GHz-spaced WDM channels modulated with 40-Gbaud PDM-16QAM. We transmit 22-Tb/s data over 2,400 km, with a spectral efficiency of 5 bit/s/Hz.

DC-100-GHz frequency doublers in InP DHBT technology

Broad-band monolithic integrated active frequency doublers operating in dc-100-GHz frequency range are presented. Circuits are fabricated in a self-aligned InP double heterojunction bipolar transistor process. Three integrated doubler versions have been designed. Inductive peaking and active splitting effects are quantified and compared. Circuit measurements give sinusoidal output waveform at 100 GHz with an rms timing jitter of 400 fs. Circuits have a maximum conversion gain of +1 dB at 60 GHz. the fundamental suppression is better than 24 dB in the whole frequency range.

InGaAs/InP DHBT technology and design methodology for over 40 Gb/s optical communication circuits

High-performance technologies and adequate design methodologies are required to address the needs of very high-speed ICs (VHSICs) for over 40 Gb/s optical communications. We describe improvements we have introduced in our InP DHBT technology, and how our design methodology has evolved, we show how it results in improved circuit designs, and present some recent results, with some considerations on measurement limitations.

Single-carrier 400G interface and 10-channel WDM transmission over 4,800 km using all-ETDM 107-Gbaud PDM-QPSK

We transmit all-electronically multiplexed 107-Gbaud polarization-multiplexed quadrature-phase-shift-keying over 4,800-km using coherent detection based on a real-time oscilloscope with 63-GHz electronic bandwidth. Ten WDM channels on a 120-GHz grid yield a spectral efficiency of 3.3 b/s/Hz.