Impact of Dispersion Effects on Temporal-Convolution-Based Real-Time Fourier Transformation Systems

Abstract

The impact of dispersion effects on temporal-convolution-based real-time Fourier transformation (RTFT) systems, including the residual 2 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">nd</sup> -order dispersion effect, the 3 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">rd</sup> -order dispersion effect, and their joint effect, is theoretically analyzed. To reduce these effects, an optical RTFT system based on a bidirectional chirped fiber Bragg grating (CFBG) and an optical filter is proposed. Only one optical pulse source, a bidirectional CFBG, a Mach-Zehnder modulator (MZM) and a photodetector (PD) are needed. RTFT with a bandwidth of 40 GHz and a frequency resolution of 0.7 GHz has been experimentally achieved.