并行光逻辑运算器件是未来高速大容量全光信号处理的关键器件,也有助于降低信息的传输时延。利用光纤四波混频的非相敏放大(FWM-PIA)机理,设计三通道光相位混合运算器(A+B-C,A+C-B,B+C-A)。通过建立并求解级联四波混频(FWM)的非线性耦合模方程组,揭示光相位运算器输出闲频光与输入信号光之间的固定相移关系,为相位补偿方法的实施提供理论依据。计算表明,该并行混合运算器的幅度噪声指数和误差矢量幅度(EVM)的相位噪声转移系数分别为0.9 dB和1.67;当输入四相相移键控(QPSK)信号的信噪比大于24 dB和EVM小于12%时,无纠错编码的符号错误率低于10 ^-3。比较三通道和单通道两种相位运算器的性能,由于相位运算器是通过FWM相位匹配关系执行混合运算功能的,它们有相同的相位噪声转移特性,但前者的噪声指数略低0.2 dB,光功率转移效率高一倍以上。

High-speed and large-capacity all-optical signal processing can be achieved in the future with the optical parallel logic operators. Such devices can help reduce data transmission delays. This study proposes a hybrid operator of three-channel optical phase for optical computing (A+B-C, A+C-B, and B+C-A) that is designed according to the phase-insensitive amplification principle of four-wave mixing (FWM) in fibers. The nonlinear coupled-mode equations for the cascade FWM are derived. Results reveal that between each output idler and input signal have a certain phase relation, which provides the theoretical basis for phase compensation. Moreover, parallel hybrid operators have amplitude noise index and phase noise transfer coefficient in terms of error vector amplitude (EVM) of 0.9 dB and 1.67, respectively. For a quadrature phase shift keying (QPSK) signal, when the signal-to-noise ratio is >24 dB and the EVM is <12%, the symbol error rate of error-free coding is <10 -3. Three- and single-channel operators exhibit the same phase noise transfer characteristics due to common FWM-phase matching conditions. However, the three-channel operator exhibits lower phase noise of 0.2 dB and larger power transfer efficiency that is more than twice that of the single-channel operator.