Polarization mode dispersion

About: Polarization mode dispersion is a research topic. Over the lifetime, 5147 publications have been published within this topic receiving 80055 citations. The topic is also known as: PMD.

Methods and apparatus for compensating chromatic and polarization mode dispersion

Abstract: Integrated and stand-alone methods and apparatus for adaptively compensating for DGD, SOPMD, and CD in optical communication networks are provided. One apparatus includes at least three optical compensators that are optically coupled together in series and a feedback controller. Each compensator includes a variable optical controller that is optically coupled in series to a birefringent element. An optical communication network is also provided that at least includes an optical transmission line, at least two network terminals, and at least one static compensation module. At least one terminal includes an optical demultiplexer that is coupled to that element, a plurality of λ-compensators, and, optionally, a static optical dispersion compensation element.

Performance of turbo equalizers for optical PMD channels

Abstract: This paper investigates the performance of iterative (turbo) equalization to mitigate the effects of a polarization-mode dispersion (PMD) in nonreturn-to-zero (NRZ) intensity-modulated optical-fiber transmission systems. A PMD can lead to severe distortions in the received electrical signal and is a key limiter for the development of high-bit-rate transmission over currently used fibers. In order to reduce the distortions due to a PMD, the performance of symbol-by-symbol maximum a posteriori (sbs-MAP) soft-in/soft-out (SISO) decoders is studied. The SISO algorithms are adapted to the noise statistics of the optical channel where the photo detector leads to a non-Gaussian signal-dependent noise at the receiver side. The modified SISO algorithms are successfully employed for turbo equalization and results show that iterative (turbo) equalization and decoding for the compensation of a PMD can lead to a tremendous reduction in the bit error ratio (BER). Moreover, it is shown that, due to the robustness of mutual information, the extrinsic information transfer (EXIT) chart can be applied for the design of iterative receivers in optical transmission systems even with a non-Gaussian noise

Performance comparison of optical 8-ary differential phase-shift keying systems with different electrical decision schemes

Abstract: We examine the performance of optical 8-ary differential phase-shift keying transmission systems according to the type of receiver structure and modulation format. Compared with the approach based on a multilevel decision, we found that a bilevel receiver provides 3-dB gain in optical signal-to-noise ratio sensitivity and is more robust against chromatic dispersion for either nonreturn-to-zero or return-to-zero modulation.

Long-term stable, sub-femtosecond timing distribution via a 1.2-km polarization-maintaining fiber link: approaching 10 −21 link stability

Abstract: Long-term stable, sub-femtosecond timing distribution over a 12-km polarization-maintaining (PM) fiber-optic link using balanced optical cross-correlators for link stabilization is demonstrated Novel dispersion-compensating PM fiber was developed to construct a dispersion-slope-compensated PM link, which eliminated slow timing drifts and jumps previously induced by polarization mode dispersion in standard single-mode fiber Numerical simulations of nonlinear pulse propagation in the fiber link confirmed potential sub-100-as timing stability for pulse energies below 70 pJ Link operation for 16 days showed ~06 fs RMS timing drift and during a 3-day interval only ~013 fs drift, which corresponds to a stability level of 10(-21)