Leonardo D. Coelho

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We derive the channel capacity of CO-OFDM systems limited by FWM. Simulations confirm that Peak-to-Average-Power-Ratio reduction techniques are suitable for FWM mitigation. These techniques can utilize the decreased capacity to significantly increase the system reach. c © 2008 Optical Society of America OCIS codes: (060.2330) Fiber optics communications;(More)
Vocal fold paralysis is associated with involvement of the vagus nerve or the recurrent laryngeal nerve between the jugular foramen and the entry point into the larynx. Malignancies of the thyroid are a frequent cause, but vocal fold paralysis is also found in certain benign diseases. In a series of 1,200 cases, the incidence of the association between(More)
Different pulse shapes are presented as alternative to traditional (N)RZ pulses in communication systems using direct detection. The pulses are efficiently generated in the frequency domain using the discrete Fourier transform. The trade-off between spectral occupancy and eye opening is discussed and performance is evaluated by means of simulations.
Using an alternative approach for evaluating the Bit-Error Rate (BER), we present a numerical and experimental investigation of the performance of phase-modulated optical communication systems in the presence of nonlinear phase noise and dispersion. The numerical method is based on the well known Karhunen-Lo;eve expansion combined with a linearization(More)
We present Stereo Multiplexing, a novel technique that permits simultaneous direct detection of two modulated optical carriers. This is accomplished by modulating the optical carriers with the difference and the sum of two signals. The linear performance of Stereo-multiplexed DQPSK signals is compared to single-carrier DQPSK and dual-carrier DQPSK.(More)
In this work we present and analyze three approaches for the adaptive control of the operating point of a cascade of erbium-doped fiber amplifiers (EDFAs), aimed at optical networks performance enhancement. The first approach is called Annealing Search Heuristic with Backpropagation and flexible output (AsHB flex) and uses machine learning concepts to(More)
We present Stereo Multiplexing, a novel technique that permits simultaneous direct detection of two modulated optical carriers. This is accomplished by modulating the optical carriers with the difference and the sum of two signals. The linear performance of Stereo-multiplexed DQPSK signals is compared to single-carrier DQPSK and dualcarrier DQPSK.(More)
background: Diabetics, especially insulin -treated diabetics, have more extensive coronary atherosclerosis and impaired vascular remodeling. Our objective was to evaluate in-hospital results of contemporaneous percutaneous coronary intervention (PCI) in a consecutive series of diabetics treated with (ITD) or without (NITD) insulin. Methods: Retrospective(More)
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