Simultaneous single-shot real-time measurement of the instantaneous frequency and phase profiles of wavelength-division-multiplexed signals

Abstract

A self-reference, single-shot characterization technique is proposed and demonstrated for simultaneously measuring the instantaneous frequencies and phases of multi-wavelength optical signals using a single processing and detection platform. The technique enables direct real-time optical sampling of the instantaneous frequencies of amplitude and/or phase modulated signals simultaneously at different wavelengths without requiring the use of any optical reference. Simultaneous real-time instantaneous frequency and phase measurements of a chirped 1 GHz-sinusoid intensity modulation signal and a 3 Gbps-PRBS (pseudo-random binary sequence) phase-modulated signal at two different wavelength channels have been performed for the proof-of-concept demonstration.

Time resolved chirp measurements of gain switched semiconductor laser using a polarization based optical differentiator

“…A balanced temporal PROUD [29,30] can be implemented by replacing the rotatable polarizer in Fig. 1 by a polarizing beam splitter, which, when properly aligned with respect to the PMF, would provide two outputs equivalent to the outputs of a conventional MZ interferometer.…”

Linear self-referenced complex-field characterization of fast optical signals using photonic differentiation

“…Recent demonstrations include both linear implementations of concepts previously proved with non-linear processes (e.g. spectrography [18,19] and spectral self-interferometry [20,21]) and fundamentally new linearoptics pulse measurement schemes [22][23][24][25][26][27][28][29][30][31][32][33][34][35][36][37][38]. As compared with more conventional non-linear optics techniques, linear-optics methods offer an increased sensitivity and they can be implemented in very simple and practical (e.g.…”

“…fiber-based) platforms. In this paper, we review a recent body of work on a new group of linear and selfreferenced techniques for full characterization and monitoring of fast optical signals based upon the concept of photonic differentiation, generally referred to as 'phase reconstruction using optical ultrafast differentiation' (PROUD) [33][34][35][36][37][38]. These methods are particularly well adapted to the problem of signal characterization in the context of optical telecommunications.…”

“…These methods are particularly well adapted to the problem of signal characterization in the context of optical telecommunications. PROUD techniques can be used for full characterization of optical signals, including continuous-time data streams, over a very wide range of pulse time durations, from~100 fs to well in the nanosecond regime [33][34][35]; they can provide measurements in a single-shot and in a real-time with power sensitivities down to the microwatt level [36][37][38]. Real-time operation is in part enabled by the fact that the PROUD methods rely on a simple, non-iterative phase recovery numerical algorithm (simple analytic equation).…”

Proposal of time-resolved chirp-measurement through all-optical in-fiber mathematical operators

“…This technique involves the measurement of the temporal intensity profiles at the input and outputs of a first-order temporal differentiator. This method -referred to as PROUD (Phase Reconstruction using Optical Ultrafast Differentiation)-has been later optimized to achieve single-shot capabilities (Li et al 2009) as well as to characterize multi-wavelength waveforms (Park et al 2010).…”