Ivan T. Lima

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—In this letter, we use importance sampling to analyze polarization-mode dispersion compensators with a constant differential group delay (DGD) element. We optimize the value of the fixed DGD element of the compensator with respect to the outage probability. We show that the optimum value of the fixed DGD element of the compensator can reduce the outage(More)
—This paper shows how to use multiple importance sampling to study the performance of polarization-mode dispersion (PMD) compensators with a single differential group delay (DGD) element. We compute the eye opening penalty margin for compensated and uncompensated systems with outage probabilities of 10 5 or less with a fraction of the computational cost(More)
—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 have demonstrated that with the loop-synchronous scrambling technique, the distribution of a recir-culating loop closely resembles that of a straight-line system. By carefully choosing the scrambling rate, we show that slow scrambling at the transmitter improves the system performance and reduces the performance variation. We investigate the system(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)