Ivan T. Lima

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This paper shows how to estimate errors in multicanonical Monte Carlo (MMC) simulations using a transitionmatrix 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 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)
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 present experimental and numerical results for nonlinear polarization evolution of femtosecond pulses during propagation in microstructure fiber. Numerical modeling shows that fiber dispersion permits a long interaction length between the components polarized along the two principal axes, thereby enhancing the effective nonlinear polarization evolution(More)
We derive a recursion relation for the frequency autocorrelation function of the polarization dispersion vector for polarization mode dispersion emulators with rotators. The autocorrelation function has a nonzero background for an emulator with a fixed number of sections. This background diminishes slowly as the number of sections grows. Randomizing the(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)
We show that electrical domain (post-detection) approaches hold great promise for mitigating distortions such as polarization mode dispersion (PMD) in optical communication systems, when they are used by taking the physical characteristics of the distortion into account. We present a polarization diversity receiver for PMD mitigation and show its(More)