The authors propose an integrated Mach–Zehnder interferometer and diversity combining receiver to mitigate the atmospheric turbulence-induced fading in a millimetre-wave (mmW) radio-over-free-space optics (RoFSO) link. They use a carrier frequency of 28 GHz as recommended for the fifth-generation wireless access networks and consider two optical mmW signal generation schemes, namely double-sideband (DSB) and single-sideband (SSB). In direct detection (DD)-based RoFSO, the link performance is limited by atmospheric turbulence. They show that the proposed Rx can overcome this detrimental effect, which is verified by investigation of a 10 Gb/s 16-quadrature amplitude modulation orthogonal frequency-division-multiplexing signal at 28 GHz over a 1 km free-space optics link under weak and strong turbulence regimes. For the DSB scenario, the proposed Rx offers improved error vector magnitudes of about 0.8 and 5.7%, and modulation error ratios of 1.3 and 4.9 dB under weak and strong turbulence regimes, respectively, compared with the DD receiver (DD Rx). For the SSB scenario under weak turbulence, the proposed Rx achieves a 4 dB improvement in the receiver sensitivity and four orders of magnitude enhancement in the bit error rate over the DD Rx. The proposed Rx can be integrated on a single chip for further cost reduction.

中文翻译：

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使用集成的Mach–Zehnder干涉仪和分集组合接收器来缓解28 GHz自由空间无线电链路中的湍流

作者提出了一种集成的Mach-Zehnder干涉仪和分集组合接收机，以减轻毫米波（mmW）自由空间无线电（RoFSO）链路中大气湍流引起的衰落。他们使用第五代无线接入网络推荐的28 GHz载波频率，并考虑了两种光学mmW信号生成方案，即双边带（DSB）和单边带（SSB）。在基于直接检测（DD）的RoFSO中，链路性能受到大气湍流的限制。他们表明，提出的Rx可以克服这种不利影响，这一点已通过在弱和弱电条件下，在1 km自由空间光链路上对28 GHz的10 Gb / s 16正交幅度调制正交频分多路复用信号进行研究得到了验证。强大的湍流状态。对于DSB方案，与DD接收机（DD Rx）相比，建议的Rx在弱湍流和强湍流条件下分别提供了约0.8和5.7％的改进的误差矢量幅度，以及1.3和4.9 dB的调制误差比。对于弱湍流下的SSB场景，与DD Rx相比，建议的Rx将接收器灵敏度提高4 dB，并将误码率提高四个数量级。提议的Rx可以集成在单个芯片上，以进一步降低成本。与DD Rx相比，建议的Rx将接收机灵敏度提高了4 dB，并将误码率提高了四个数量级。提议的Rx可以集成在单个芯片上，以进一步降低成本。与DD Rx相比，建议的Rx将接收机灵敏度提高了4 dB，并将误码率提高了四个数量级。提议的Rx可以集成在单个芯片上，以进一步降低成本。