Article

Output Power PDF of a Saturated Semiconductor Optical Amplifier: Second-Order Noise Contributions by Path Integral Method

Tech. Univ. of Denmark, Kgs. Lyngby
IEEE Journal of Quantum Electronics (Impact Factor: 2.11). 01/2008; DOI: 10.1109/JQE.2007.906226
Source: IEEE Xplore

ABSTRACT We have developed a second-order small-signal model for describing the nonlinear redistribution of noise in a saturated semiconductor optical amplifier. In this paper, the details of the model are presented. A numerical example is used to compare the model to statistical simulations. We show that the proper inclusion of second-order noise terms is required for describing the change in the skewness (third-order moment) of the noise distributions. The calculated probability density functions are described far out in the tails and can hence describe signals with very low bit error rate (BER). The work is relevant for describing the noise distribution and BER in, for example, optical regeneration.

0 Bookmarks
 · 
66 Views
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: We present a theoretical method for calculating small-signal modulation responses and noise spectra of active Fabry-Perot semiconductor waveguides with external light injection. Small-signal responses due to either a modulation of the pump current or due to an optical amplitude or phase modulation of the input field can be calculated. Both responses and noise spectra are given through semianalytical expressions taking into account the longitudinal extent and finite end-facet reflectivities of the active device. Different examples of responses and spectra are presented for semiconductor optical amplifiers and an injection-locked laser. We also demonstrate the applicability of the method to analyze slow and fast light effects in semiconductor waveguides. Finite reflectivities of the facets are found to influence the phase changes of the injected microwave-modulated light.
    IEEE Journal of Quantum Electronics 09/2009; · 2.11 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: We present a simulation tool based on the Multicanonical Monte Carlo (MMC) method to characterize the statistical properties of bit patterning in semiconductor optical amplifiers (SOAs). Our tool estimates the conditional probability density functions (PDFs) of marks and spaces of the received signal. We introduce an experimental technique to directly measure the conditional PDFs of the received marks and spaces using a high bandwidth sampling scope. We demonstrate that predictions from our simulation tool match the experimental data. We measure the bit error rate (BER) of a SOA-based preamplified receiver, where the SOA operates in the nonlinear regime, and demonstrate that our simulation tool can predict the measured BER.
    IEEE Journal of Quantum Electronics 05/2010; · 2.11 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: We address design and optimization of optical filters for spectrum-sliced wavelength division multiplexed (SS-WDM) systems employing saturated semiconductor optical amplifiers (SOAs) to suppress intensity noise. We study the impact of the shape of both slicing and channel selecting optical filters vis-a-vis two important impairments: the filtering effect and the crosstalk. The quantification of bit error rate (BER) is made possible by a parallel implementation of the multicanonical Monte Carlo algorithm. The intensity noise suppression by the SOA and signal degradation by subsequent optical filtering are studied both numerically and experimentally. We find optical filter shape and bandwidth that minimizes BER. By varying channel spacing and width, we estimate the achievable spectral efficiency when using both noise-cleaning SOA and forward error correction. We show that when constrained to use a symmetric architecture, i.e., identical filters for both slicing and channel selecting filters, there is a degradation in achievable spectral efficiency. We show that noise suppression is robust to variations in relative channel powers in multichannel systems. Our numerical simulations, vetted experimentally, provide accurate and quantitative results on optimized system performance.
    Journal of Lightwave Technology 02/2010; · 2.56 Impact Factor

Full-text

View
2 Downloads
Available from