PMD Compensation/mitigation techniques for high-speed optical transport

Abstract

optical and electrical compensation techniques that apply optical signal processing within an optical PMD compensator (PMDC) unit or post-detection electronic signal processing of the photodiode signal by an electronic equalizer within the receiver.In this paper, we review the advances in optical and electronic technologies for PMD mitigation. We first briefly analyze the impact of installed fiber PMD on a transmission system and how to quantify it. The principle and structure of optical PMDCs are described next. The impact of modulation formats on the design of optical PMDCs as well as the performance of a twostage optical PMDC for 40 Gb/s non-return-to-zero differential phase shift keying (NRZ-DPSK) will be discussed. We follow with a discussion of electronic equalizers, which process the electrical signal provided

Outage in PMD compensated optical fiber line due to uncertainty of PMD estimation

“…In case of the considered PMD monitor the polarization information is lacking which excludes a use of this monitor in conjunction with an optical compensator. For electronic mitigation of PMD effects there are two options: the Feedforward Equalizer (FFE) or the Decision Feedback Equalizer (DFE) [1]. The FFE (ref.…”

“…where: S() is spectrum of the symbol signal, C(,,) is the transfer characteristics of the PMD affected intensity modulated (IM) optical channel,  and  are the actual values of DGD and power split ratio that characterize the state of the first order PMD in the fiber. The other quantities in (1): N() and A() are two sided power spectral densities of noise and transmitted data respectively, SN(,,) is two sided power spectral density of signal to noise ratio. The (X) is the folding function which outputs spectrum being equivalent to the one effected by signal sampling.…”

“…PMD compensators, both optical and electronic, were studied extensively. In particular, individual compensator structures were optimized and characterized with respect to achievable range of tolerance for Differential Group Delay (DGD) excursions and gain in outage probability [1].…”

PMD Mitigation by Various Distribution Patterns of Fast Polarization Scramblers with Forward Error Correction

“…Polarization mode dispersion (PMD) occurs in a highspeed optical fiber system, which leads significantly to transmission impairments [1]. PMD compensation and mitigation techniques have attracted considerable attention in recent years [2]. The joint distributed fast polarization scramblers (D-FPSs) and forward error correction (FEC) as a PMD mitigation scheme has been proposed and presents remarkable effect [3] [4].…”

Optical polarization mode dispersion compensators for high-speed optical communication systems

“…PMD not only varies randomly over the wavelength, which gives rise to higher order PMD, but drifts randomly with time as well due to environmental changes such as temperature variations and mechanical vibrations along the fiber.To reduce PMD impairments, various PMD mitigation techniques have been proposed and demonstrated [2]. In general, PMD mitigation techniques can be divided into three main approaches:…”