All-Optical Phase Quantization with High Accuracy Based on a Multiwave Interference Phase Sensitive Amplifier

A scheme of all-optical multilevel phase quantization with high accuracy based on multiwave interference is proposed. The influences of the amplitude ratios of the conjugate (N - 1)th and (N + 1)th harmonics to the signal on phase quantization accuracy are researched. The characteristics of the phase quantization output with the amplitude ratios variation are discovered. By using the proposed scheme, the output phase is more concentrated than that of the traditional method for multilevel phase quantization. The simulations show the effectiveness of the scheme for the three levels quantization and the application of four levels quantization to the quadrature phase shift keying signal regeneration.