ABSTRACT Nowadays, public demands high capacity global internet traffic in terms of cloud computing, video gaming, fiber to the home and mobile networks, etc. To fulfill such huge traffic requirement, high-speed digital coherent transmission system came into the picture. Polarization multiplexed-quadrature phase shift keying (PM-QPSK) technique is an emerged praiseworthy digital coherent optical multiplexing technology. PM-QPSK provides efficient bandwidth to fulfill the high traffic demands by availing enormous potential bandwidth of optical fiber. PM-QPSK is a good hybrid multiplexed candidate in terms of delivering high optimized receiver sensitivity and spectral efficiency with appreciable reach. In this survey, we present a state of art over different strategies employing PM-QPSK techniques to achieve an enhancement in various optical performance parameters. During the survey, various research challenges are encountered, which are also presented with various future prospects.

中文翻译：

---

相干 PM-QPSK 技术及其变体的成功之旅：调查

摘要 如今，在云计算、视频游戏、光纤到户和移动网络等方面，公众需要大容量的全球互联网流量。为了满足如此巨大的流量需求，高速数字相干传输系统应运而生。偏振复用正交相移键控(PM-QPSK)技术是一种新兴的、值得称道的数字相干光复用技术。PM-QPSK 通过利用光纤的巨大潜在带宽来提供高效的带宽来满足高流量需求。PM-QPSK 是一种很好的混合多路复用候选方案，可提供高度优化的接收器灵敏度和频谱效率以及可观的覆盖范围。在本次调查中，我们展示了采用 PM-QPSK 技术的不同策略的最新技术，以实现各种光学性能参数的增强。在调查过程中，遇到了各种各样的研究挑战，也呈现出各种各样的未来前景。