Abstract. A high-capacity spectral-efficient dual-polarization quadrature phase-shift keying (DP-QPSK)-polarization shift-keying (PolSK) hybrid modulation scheme for terrestrial free-space optics (FSO) transmission link is proposed and investigated. A DP-QPSK signal modulated at 300 Gbps and a PolSK signal modulated at 40 Gbps are simultaneously transmitted using a single optical carrier over the FSO link. The proposed link performance is investigated under different weather conditions, where the bit error rate metric is used to evaluate the performance of the PolSK modulated signal and the error vector magnitude parameter is used for the DP-QPSK signal. The FSO link range and the required received power are carefully explored. The conducted numerical simulations of the proposed system showed reliable 340-Gbps data transmission over link ranges varying from 1.6125 to 50 km depending on the weather conditions. The impact of the channel scintillation due to atmospheric turbulence is also investigated. The proposed high-speed FSO transmission system offers a promising solution for high-bandwidth hungry systems used for the internet of things, 5G, and smart cities. It can also be used in developing fronthaul/backhaul links for future wireless networks and optical access networks. The performance of the proposed transmission system is compared with recently published work in the literature.

中文翻译：

---

结合频谱高效 DP-QPSK-PolSK 混合调制方案的 340 Gbps 地面 FSO 链路的研究

摘要。提出并研究了一种用于地面自由空间光学 (FSO) 传输链路的高容量频谱效率双偏振正交相移键控 (DP-QPSK)-偏振移键控 (PolSK) 混合调制方案。以 300 Gbps 调制的 DP-QPSK 信号和以 40 Gbps 调制的 PolSK 信号使用单个光载波通过 FSO 链路同时传输。在不同的天气条件下研究了所提出的链路性能，其中误码率度量用于评估 PolSK 调制信号的性能，误差矢量幅度参数用于 DP-QPSK 信号。仔细研究了 FSO 链路范围和所需的接收功率。所提出系统的进行的数值模拟表明，根据天气条件，在 1.6125 至 50 公里的链路范围内可以进行可靠的 340 Gbps 数据传输。还研究了由于大气湍流引起的通道闪烁的影响。拟议的高速 FSO 传输系统为用于物联网、5G 和智慧城市的高带宽饥饿系统提供了有前途的解决方案。它还可以用于为未来的无线网络和光接入网络开发前传/回传链路。将所提出的传输系统的性能与最近发表的文献工作进行了比较。拟议的高速 FSO 传输系统为用于物联网、5G 和智慧城市的高带宽饥饿系统提供了有前途的解决方案。它还可以用于为未来的无线网络和光接入网络开发前传/回传链路。所提出的传输系统的性能与最近发表的文献工作进行了比较。拟议的高速 FSO 传输系统为用于物联网、5G 和智慧城市的高带宽饥饿系统提供了有前途的解决方案。它还可以用于为未来的无线网络和光接入网络开发前传/回传链路。将所提出的传输系统的性能与最近发表的文献工作进行了比较。