All-optical phase-preserving amplitude regeneration of highorder modulated signals based on Mach-Zehnder interferometers

Abstract

We propose a phase-preserving multilevel amplitude regeneration scheme based on Mach-Zehnder interferometers. For geometrically shaped 16-QAM signals, the EVM performance is improved by 2.5dB and consequently the higher SNR tolerance is achieved for regenerative links.