Phase Distortions in Optical Transmission Systems

Abstract

Phase distortions due to optical components play an important role in high speed optical transmission systems. Measurement methods for the phase transfer function of components are compared. As typical examples the phase distortions of two arrayed waveguide grating demultiplexers, a fiber Bragg grating add/drop filter and a dispersion compensating fiber Bragg grating are presented. Their resulting system impact is evaluated by means of experiments, simulations and an analytical model. Übersicht Phasenverzerrungen durch optische Komponenten spielen in hochratigen optischen Übertragungssystemen eine immer größere Rolle. Es werden Meßverfahren zur Bestimmung des Phasengangs optischer Komponenten miteinander verglichen. Als typische Beispiele werden Phasenverzerrungen von zwei AWG-Demultiplexem. eines Fasergitters als Bandpaßfilter und eines dispersionskompensierenden Fasergitters vorgestellt und die daraus resultierenden Signalverzerrungen durch Experimente, Simulationen und ein analytisches Modell behandelt. Für die Dokumentation Phasenverzerrung / Optische Übertragung / Optische Gruppenlaufzeitmessung / AWG-Demultiplexer / Fasergitter / Phasengang 42

Broadband fiber Bragg gratings for dispersion management

“…These phase measurements are repeated at intervals across the wavelength range of interest, and then a relative time delay between the measurement points is calculated. The next discussion, which closely follows the presentation in [76], considers the case of amplitude modulation of a light carrier with angular frequency ω 0 by a sinusoidal signal of angular frequency ω m . The input signal electric field E i can be written as…”

“…[75][76][77] Typically the output of a narrowband tunable optical laser is intensity modulated and applied to the device under test (DUT). The transmitted signal from the DUT is detected and the phase of its intensity modulation is measured relative to that driving the input signal.…”

“…A plot of the amplitude measurements exhibits characteristic dips corresponding to amplitude modulation of the output signal. [75,76] Chirped gratings often exhibit rapidly varying amplitude and phase variations, which complicates calculations relying on Eq. (28).…”