Optical Phase Conjugation Using Nonlinear SOA for Nonlinearity and Dispersion Compensation of Coherent Multi-Carrier Lightwave Systems

We study the use of nonlinear semiconductor optical amplifier (SOA) for generating optical phase conjugate towards compensation of distortions in short distance optical fiber transmission due to Kerr nonlinearity and chromatic dispersion in coherent multi-carrier lightwave signals. We experimentally demonstrate the effectiveness of the SOA-based phase conjugator to improve the link budget with a 100 km standard single mode fiber link for 20 GHz coherent OEDM signals, with QPSK and 16QAM modulations and a corresponding net bit-rate of 40 Gbps and 80 Gbps respectively. Mid-span spectral inversion scheme is employed where the optical phase conjugate is generated through a partially degenerate four-wave mixing process in a nonlinear SOA. We demonstrate a bit error rate performance within 2 x 10(-2) for an average launched power of up to 12 dBm (9 dBm) for QPSK (16QAM) coherent OFDM signals, in a 100 km fiber link. We also investigate the possible improvement in link budget using numerical simulation for 16QAM and 64QAM CO-OFDM signals with the proposed scheme.

Automated summary

The study explores the use of nonlinear semiconductor optical amplifiers (SOAs) to generate optical phase conjugates for compensating distortions in short distance optical fiber transmission caused by Kerr nonlinearity and chromatic dispersion in coherent multi-carrier lightwave signals. Experimental results demonstrate significant improvement in link budget using SOA-based phase conjugators in a 100 km standard single mode fiber link, showcasing promising bit error rate performance for QPSK and 16QAM coherent OFDM signals. Additional investigation through numerical simulations indicates potential enhancements in link budget with proposed schemes for 16QAM and 64QAM CO-OFDM signals.