This paper investigates the performances of differential phase shift keying (DPSK) and quadrature phase shift keying (QPSK) for 400 channels super dense system for the data rate of 160, 170, 180 and 200[Formula: see text]Gbps, respectively. Evaluation has also been investigated in terms of bit error rate (BER), quality factor and received output power with varying input power. Final analysis has reflected that DPSK modulation has shown the acceptable performance in terms of better communication with minor effect of nonlinearity and dispersion using RAMAN-EDFA hybrid optical amplifier (HOA) for the distance of 250[Formula: see text]km.

中文翻译：

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超密集波分复用系统的DPSK和QPSK性能优化

本文研究了差分相移键控 (DPSK) 和正交相移键控 (QPSK) 在数据速率分别为 160、170、180 和 200 [公式：见正文]Gbps 的 400 通道超密集系统中的性能。评估还根据误码率 (BER)、品质因数和不同输入功率的接收输出功率进行了研究。最终分析表明，DPSK 调制在 250[公式：见正文]km 的距离内使用拉曼-EDFA 混合光放大器 (HOA) 在更好的通信方面表现出可接受的性能，非线性和色散的影响较小。