We numerically simulate and experimentally demonstrate an approach to potentially enhance the performance of a high-order quadrature amplitude modulation (QAM) channel by adding correlated data to other robust binary-phase-shift-keyed (BPSK) or quadrature-phase-shift-keyed (QPSK) channels. The correlated data are introduced by optically multiplying the BPSK or QPSK channels, already modulated with their own data, by the target high-order QAM data of the same baud rate. After joint detection and signal processing, a $\sim 3\mathrm{dB}$ optical signal-to-noise (OSNR) improvement is observed in simulations by comparing the performance of the target QAM channel (from 4QAM to 256QAM) with and without the use of channel correlation. We also experimentally demonstrate the scheme for a QPSK or a 16QAM target channel using BPSK correlated channels. A $\ge 2\mathrm{dB}$ OSNR improvement is observed.

中文翻译：

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通过将相关数据添加到健壮的相邻BPSK或QPSK信道来增强光学高阶QAM信道的性能

我们通过数值模拟和实验演示了一种通过将相关数据添加到其他健壮的二进制相移键控（BPSK）或正交相移键控来潜在地增强高阶正交调幅（QAM）通道性能的方法（QPSK）频道。通过将已经用它们自己的数据调制的BPSK或QPSK信道与相同波特率的目标高阶QAM数据进行光学相乘，可以引入相关数据。经过联合检测和信号处理后，$〜3\mathrm{D\; b}$通过比较使用和不使用信道相关性的目标QAM信道（从4QAM到256QAM）的性能，可以在仿真中观察到光信噪比（OSNR）的提高。我们还通过实验证明了使用BPSK相关通道的QPSK或16QAM目标通道的方案。一个$\ge \mathrm{2个}\mathrm{D\; b}$ 观察到OSNR的改善。