This Letter proposes a high-performance radio-over-fiber (RoF) system for high-speed and high-fidelity analog waveform transmission of radio signals in the millimeter-wave band in the uplink direction. At the antenna site, the system utilizes a newly fabricated low half-wave voltage broadband phase modulator to convert a millimeter-wave radio signal into an optical signal. At the receiver, by using photonic downconversion and optical filtering technology, a simple direct detection and downconversion of the signal to the microwave band can be achieved simultaneously. As a demonstration of proof of concept, we successfully transmitted a 1024-quadrature amplitude modulation (QAM) narrowband orthogonal frequency-division multiplexing signal at 38 GHz and a 60 Gb/s 64-QAM single-carrier signal at 26.5 GHz over a 20 km RoF system. The system is promising for facilitating the deployment of ultra-dense small cells in high-frequency bands in 5G and beyond networks.

中文翻译：

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使用光相位调制和光子下变频的毫米波光纤无线电系统用于上行链路前传传输

该信函提出了一种高性能的光纤无线电（RoF）系统，用于在上行链路方向上毫米波段中的无线电信号进行高速和高保真度的模拟波形传输。在天线站点，该系统利用新制造的低半波电压宽带相位调制器将毫米波无线电信号转换为光信号。在接收器处，通过使用光子下变频和光学滤波技术，可以同时实现对信号到微波频带的简单直接检测和下变频。作为概念验证的证明，我们成功地在20 km上传输了38 GHz的1024正交幅度调制（QAM）窄带正交频分复用信号和26.5 GHz的60 Gb / s 64-QAM单载波信号RoF系统。