Maximum likelihood sequence estimation in the presence of chromatic and polarization mode dispersion in intensity modulation/direct detection optical channels

• Published in: 2004 IEEE International Conference on Communications (IEEE Cat. No.04CH37577) Vol. 5; pp. 2787 - 2793 Vol.5
• Main Authors: Agazzi, O.E., Crivelli, D.E., Carrer, H.S.
• Format: Conference Proceeding
• Language: English
• Published: Piscataway, New Jersey IEEE 2004
• Subjects: Applied sciences; Exact sciences and technology; Fiber nonlinear optics; Intensity modulation; Maximum likelihood detection; Maximum likelihood estimation; Nonlinear optics; Optical detectors; Optical fiber communications; Optical modulation; Optical noise; Optical receivers; Optical telecommunications; Polarization mode dispersion; Systems, networks and services of telecommunications; Telecommunications; Telecommunications and information theory; Transmission and modulation (techniques and equipments); Maximum likelihood sequence estimation; Single mode fiber; Computer simulation; Error rate; Prediction theory; Non linear channel; Polarization mode dispersion; Metropolitan area network; Implementation; Amplified spontaneous emission; Optical fiber amplifiers; Statistical method; Direct modulation; Direct detection; Noise source; Probability density function; Optical receiver; Optical fiber communication; Long distance transmission; Optical modulation; Optical fiber
• ISBN: 0780385330; 9780780385337
• DOI: 10.1109/ICC.2004.1313038

In this paper we investigate maximum likelihood sequence estimation (MLSE) receivers operating on intensity modulated direct detection optical channels. Our study focuses on long haul or metro links spanning several hundred kilometers of single mode fiber with optical amplifiers. We describe the structure of MLSE-based optical receivers operating in the presence of dispersion and amplified spontaneous emission (ASE) noise, and we develop a theory of the error rate of these receivers. Computer simulations show a close agreement between the predictions of the theory and simulation results. We also address some important implementation issues. Optical channels suffer from impairments that set them apart from other channels and therefore they need a special investigation. Among these impairments are the facts that the optical channel is nonlinear, and the dominant source of noise is often ASE noise, which is distributed according to a noncentral chi-square probability density function (pdf). Additionally, optical fibers suffer from chromatic and polarization mode dispersion (PMD). Although the use of MLSE in optical channels has been discussed in earlier literature (J. H. Winter and R. D. Githin, Sept. 1990) (H.F. Haunstein et. al., 2001) no detailed analysis of optical receivers using this technique has been reported so far. This motivates the study reported in this paper.