All-optical analog-to-digital conversion using split-and-delay technique

作者：Miyoshi Yuji^*; Ikeda Kensuke; Tobioka Hideaki; Inoue Takashi; Namiki Shu; Kitayama Ken Ichi

来源：Journal of Lightwave Technology, 2007, 25(6): 1339-1347.

DOI：10.1109/JLT.2007.895534

• all-optical signal processing
• analog-to-digital (A/D) conversion
• nonlinear optical loop mirror (NOLM)
• Sagnac interferometer

We propose a simplified configuration of all-optical analog-to-digital (A/D) conversion using nonlinear optical loop mirrors (NOLMs). While the conventional scheme of such all-optical A/D conversion requires N encoders and N thresholders, for N-bit resolution, the proposed configuration realizes an N-bit resolution only using a single encoder and thresholder, based on a split-and-delay technique, in which the encoder and the thresholder operate more than N times as fast as the sampling speed. After discussing detailed design issues of the NOLM-based encoder with particular emphasis on the so-called counterpropagating effects, all-optical 3-bit A/D conversion at 10 GS/s is experimentally demonstrated using the proposed configuration.

• 出版日期2007-6