Jeffrey H. Sinsky

High-speed electrical backplane transmission using duobinary signaling

High-speed electrical data transmission through low-cost backplanes is a particularly challenging problem. We present for the first time a very effective approach that uses the concept of duobinary signaling to accomplish this task. Using a finite-impulse-response filter, we are able to compensate for the phase and amplitude response of the backplane such that the resulting frequency response of the channel is that of an ideal duobinary filter. At the output of the backplane, we use an innovative pseudodigital circuit to convert the electrical duobinary to binary. For 10-Gb/s data transmission, we demonstrate a bit error rate <10/sup -13/ through electrical backplane traces up to 34 in in length on FR4. A full discussion of the concept, system architecture, and measured results are presented. Analysis is presented that compares and contrasts this approach to PAM-4 and standard nonreturn-to-zero signaling.

Compensation of intra-channel nonlinearities in 40 Gb/s pseudo-linear systems using optical phase conjugation

We compensate intra-channel nonlinearities in an RZ-DPSK-40 Gb/s 32/spl times/100 km system using a LiNbO/sub 3/ conjugator and achieve 2 decades of improvement in BER. Transmission limited to 5200 km at a BER=5/spl times/10/sup -4/ is extended to 6400 km with phase conjugation.

Compact High-Speed InP DQPSK Modulator

We present a novel InP differential quadrature phase-shift-keying modulator design comprised of two electroabsorption modulators in a three-arm interferometer. The modulator is extremely compact, measuring only 1500 mum times 250 mum. We demonstrate it at 21.4 Gb/s and investigate preliminary performance at 107 Gb/s.

RZ-DPSK transmission using a 42.7-Gb/s integrated balanced optical front end with record sensitivity

We have demonstrated a record sensitivity of -37.0 dBm (38 photons/bit) for a BER of 10/sup -9/ at 42.7-Gb/s using an integrated balanced optical front end. Results were obtained using optical preamplification of RZ-DPSK modulation and an external delay-interferometer. The OSNR requirement was measured to be 16.9 dB in a 0.1-nm bandwidth. The impact of polarization-mode dispersion (PMD) and chromatic dispersion on the optical front end performance has been measured. Performance for enhanced forward error correction has been projected based on 10/sup -3/ BER performance.

Monolithically integrated 40-gb/s switchable wavelength converter

An all-optical switchable wavelength-converting module at 40 Gb/s line rate is demonstrated in a fully integrated InP chip. The device combines a semiconductor optical amplifier-based wavelength converter and a fast-tunable multifrequency laser. Sub-nanosecond switching among the eight channels of the integrated laser is shown, and error-free operation of the wavelength conversion process at 40 Gb/s for each wavelength is demonstrated. The applications of fast switching wavelength conversion for optical switching and packet routing are discussed.

Linear microwave-domain dispersion compensation of 10-Gb/s signals using heterodyne detection

We demonstrate heterodyne detection of 10-Gb/s signals, and subsequent linear compensation of fiber chromatic dispersion in the microwave domain. We achieve 375-km transmission (with 2-dB penalty) over standard single-mode fiber using duobinary modulation and a single passive microwave dispersion-compensating element.

10-Gb/s upgrade of bidirectional CWDM systems using electronic equalization and FEC

We discuss options for upgrading coarse wavelength-division multiplexed (CWDM) optical access links over standard single-mode fiber (SSMF) by increasing per-channel data rates from 2.5 to 10 Gb/s. We identify electronic equalization and forward error correction (FEC) as the enabling technologies to overcome the dispersion limit of SSMF. In addition, we show how FEC enhances the tolerance to in-band crosstalk, and paves the way toward fully bidirectional CWDM transmission. Due to the lack of CWDM sources rated for 10-Gb/s operation, we demonstrate full-spectrum (1310 to 1610 nm) 10-Gb/s CWDM transmission over standard-dispersion fiber using uncooled, directly modulated lasers specified for 2.5 Gb/s. All 16 CWDM channels could be transmitted over more than 40 km, yielding a capacity-times-distance product of 6.4 Tb/s/km. The longest transmission distance (80 km) was achieved at 1610 nm, equivalent to 1600 ps/nm of chromatic dispersion.

Modified Rational Function Modeling Technique for High Speed Circuits

This paper presents a modified rational function modeling technique for high speed circuits. It models the scattering parameters (S-parameters) of high speed circuits with modified rational functions. S-parameters can be directly measured or simulated using traditional circuit simulation tools, and the poles and residues of modified rational functions are determined by a vector fitting algorithm. Compared to the traditional rational functions, far fewer poles are needed. With the modified rational functions, the time-domain-reflectometry, time-domain-transmission waveforms and output signals of high speed circuits can be easily expressed in closed-forms, providing a simple way to do quasi-analytic time domain analysis of measured microwave structures. The presented modeling technique is demonstrated for a differential transmission channel on a high-speed electrical backplane

A 107-Gbit/s Optoelectronic Receiver Utilizing Hybrid Integration of a Photodetector and Electronic Demultiplexer

A novel 107-Gbit/s optoelectronic receiver has been designed using hybrid integration of a photodiode and electronic demultiplexer. Using an ETDM transmitter, we achieve the lowest reported required OSNR for 107-Gbit/s CSRZ-OOK, 21 dB for 10-3 BER and a 231-1pattern length. Design methodology and performance data are presented.

A 40-Gb/s integrated balanced optical front end and RZ-DPSK performance

We have designed and built an integrated balanced optical front end suitable for detecting RZ-DPSK transmissions when used with an external delay-interferometer. We have achieved an optically preamplified sensitivity of -35.7 dBm at a BER of 10/sup -9/ and an optical signal-to-noise ratio of 18.3 dB in a 0.1-nm bandwidth at 40 Gb/s. To the best of our knowledge, this is the first demonstration of 40-Gb/s RZ-DPSK reception with an integrated hybrid optical front end.