David J. Krause

Performance of Dual-Polarization QPSK for Optical Transport Systems

The emergence of capable semiconductor processes has allowed digital signal processing to extend the application range of high-capacity optical systems. We report the performance of polarization multiplexed (or dual-polarization) quadrature phase-shift keying at 40 and 100 Gb/s.

Terabit/s class InP photonic integrated circuits

In this paper, we review recent developments in the area of terabit/s?class monolithically integrated, transmitter and receiver photonic integrated circuits for the implementation of coherent, polarization-multiplexed, quadrature phase shift keying and higher order modulation formats.

SPM-Tolerant Pulse Shaping for 40- and 100-Gb/s Dual-Polarization QPSK Systems

An intersymbol-interference-free pulse shape is specifically designed for self-phase-modulation (SPM) mitigation. It is experimentally shown to increase the SPM tolerance of a 40-Gb/s single-channel postcompensated dual-polarization quadrature phase-shift keying system by 1.5 dB. Numerical analyses at 40 and 100 Gb/s indicate that the specialized pulse shape can increase the maximum reach for G.652 fiber and G.655 fiber up to 1190 and 820 km, respectively.

Precompensation for Narrow Optical Filtering of 10-Gb/s Intensity Modulated Signals

Signals in spectrally efficient optical networks can be distorted by the narrowing of the overall bandwidth that occurs when optical add-drop multiplexers are concatenated. In this letter, it is demonstrated that the performance implications of this bandwidth narrowing can be mitigated by precompensation using arbitrary optical waveform generation. The synthesis of the required voltage waveforms for a dual-drive Mach-Zehnder modulator reduces the penalty in receiver sensitivity due to narrow optical filtering from 6.5 to 1.9 dB. Simultaneous precompensation for fiber dispersion is also demonstrated.

Demonstration of 20-Gb/s DQPSK With a Single Dual-Drive Mach–Zehnder Modulator

Using a single, dual-drive Mach-Zehnder modulator and high-speed electronics, differential quadrature phase-shift keying modulation and detection are demonstrated for a bit rate of 20 Gb/s. Back-to-back system performance is measured, and the receiver sensitivity is found to be -32.25 dBm.

Technique for measuring the optical phase transfer function

A technique for directly measuring the optical phase transfer function of optoelectronic devices is presented. The change in the phase of an optical signal is obtained as a function of a time-varying electrical stimulus for electrical-optical devices, or optical stimulus for optical-optical devices. The technique is demonstrated by considering the phase of the output signal from an electroabsorption modulator as a function of the applied voltage.

Measurement of passive optical components using a carrier and single sideband

A simple method based on arbitrary optical signal generation is presented for measuring the magnitude and phase of the transfer function of passive optical components. The method offers fine resolution along the frequency axis as well as a simple setup.

Measurement of the Jitter Transfer Function of a DFB Self-pulsating Laser Using Arbitrary Optical Waveform Generation

The jitter transfer function up to 1.24 GHz of a 10 Gb/s self-pulsating DFB laser was measured using arbitrary optical waveform generation. A cut-off frequency of 150 MHz and roll-off of 20 dB/decade were measured

Offset Sideband Modulation at 2.5 GSym/s

The generation of an optical carrier and 2.5-GSym/s offset modulated sideband is demonstrated using arbitrary optical waveform generation and a single laser and modulator. In this demonstration, the sideband is modulated using QPSK and 16-QAM.

Arbitrary Optical Waveform Generation for Advanced Optical Modulation Formats and FTTx

Arbitrary optical waveform generation is used to generate a novel optical modulation format suitable for direct detection. The system performance of the format and its application to next generation FTTx transceivers are presented