Gou Weilei, Yu Yuan, Zhang Xinliang
Wuhan National Laboratory for Optoelectronics and School of Optical and Electronic Information, Huazhong University of Science and Technology, Wuhan, 430074, China.
Optics Valley Laboratory, Wuhan, 430074, China.
Front Optoelectron. 2023 Jul 24;16(1):20. doi: 10.1007/s12200-023-00075-2.
Optical beating is the usual approach to generation of microwave signals. However, the highest frequency achievable for microwave signals is limited by the bandwidths of optoelectronic devices. To maximize the microwave frequency with a limited bandwidth of a photodetector (PD) and relieve the bandwidth bottleneck, we propose to generate microwave signals with the single sideband (SSB) format by beating a continuous wave (CW) light with an optical SSB signal. By simply adjusting the frequency difference between the CW light and the carrier of the optical SSB signal, the frequency of the generated microwave SSB signal is changed correspondingly. In the experiment, amplitude shift keying (ASK) microwave signals with the SSB format are successfully generated with different carrier frequencies and coding bit rates, and the recovered coding information agrees well with the original pseudo random binary sequence (PRBS) of 2 - 1 bits. The proposed approach can significantly relieve the bandwidth restriction set by optoelectronic devices in high-speed microwave communication systems.
光拍频是产生微波信号的常用方法。然而，微波信号可达到的最高频率受到光电器件带宽的限制。为了在光电探测器（PD）带宽有限的情况下使微波频率最大化并缓解带宽瓶颈，我们建议通过将连续波光（CW）与光学单边带（SSB）信号进行拍频来产生单边带（SSB）格式的微波信号。通过简单地调整连续波光与光学SSB信号载波之间的频率差，所产生的微波SSB信号的频率会相应改变。在实验中，成功产生了具有不同载波频率和编码比特率的单边带格式的幅移键控（ASK）微波信号，并且恢复的编码信息与2 - 1比特的原始伪随机二进制序列（PRBS）吻合良好。所提出的方法可以显著缓解高速微波通信系统中光电器件所设定的带宽限制。
