Ivan T. Lima

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—We investigate the polarization evolution for both signal and noise in two 107-km recirculating loops with polarization dependent loss per round-trip of 0.35 dB and less than 0.1 dB, respectively. When the system is optimized, in the first case, both signal and noise are polarized, while in the second case, the signal tends to depolarize due to the noise.(More)
—We analyze polarization mode dispersion (PMD) em-ulators comprised of a small number of sections of polarization-maintaining fibers with polarization scattering at the beginning of each section. Unlike previously studied devices, these emulators allow the emulation of a whole ensemble of fibers. We derive analytical expressions and determine two main(More)
—We evaluate the performance of single-section and three-section polarization-mode-dispersion (PMD) compensators using the biasing Monte Carlo methods of importance sampling (IS) and multicanonical Monte Carlo (MMC). We show that standard IS that biases only first-order PMD is insufficient to compute penalties in most compensated systems, while multiple IS(More)
—This paper shows how to estimate errors in multi-canonical Monte Carlo (MMC) simulations using a transition-matrix method. MMC is a biasing Monte Carlo technique that allows one to compute the probability of rare events, such as the outage probability in optical-fiber communication systems. Since MMC is a Monte Carlo technique, it is subject to statistical(More)
—The authors have derived a receiver model that provides an explicit relationship between the factor and the optical signal-to-noise ratio (OSNR) in optical fiber communication systems for arbitrary pulse shapes, realistic receiver filters, and arbitrarily polarized noise. It is shown how the system performance depends on both the degree of polarization of(More)
—We propose a technique that uses Monte Carlo simulations with importance sampling and a reduced Stokes model to compute the probability density function of the factor and the outage probability for a channel in a long-haul wavelength-division -multiplexed optical-fiber transmission system due to the combination of polarization mode dispersion, polarization(More)
Historically, physicists and engineers have always portrayed wave transmission using line diagrams in which the amplitude is shown as a function of time and distance. This sort of drawing tells us what is happening to the wave amplitude. However, waves are characterized by their phase as well as their amplitude, and these drawings tell us nothing about the(More)
Recent experiments have demonstrated that the bit-error rate of an optical fiber communication system can vary widely due to the random nature of the polarization effects in the system. Using a newly developed receiver model, we show that the bit-error rate depends not only on the optical signal-to-noise ratio but also on the polarization states of the(More)