Chen Jiamin, Zheng Yongqiu, Xue Chenyang, Zhang Chengfei, Chen Yi
Opt Express. 2018 May 14;26(10):12638-12647. doi: 10.1364/OE.26.012638.
Single-mode oscillation is crucial to the practicality of optoelectronic oscillator (OEO). Due to the limited by bandwidth and precision of radio frequency (RF) filters, it is difficult to be achieved for the OEO based on the long fiber-optic delay line. So instead of the long fiber-optic delay line, SiO optical waveguide ring resonator (OWRR) with high-Q and mode selection is first presented to be applied to OEO. The OEOs based on the minimum loop and SiO OWRR are constructed. The oscillation characteristics of the minimum loop OEO and the transmission characteristics of the SiO OWRR are simulated by MATLAB, respectively. The filtering effect of the SiO OWRR applied to the OEO is verified theoretically by comparing these simulation results. Subsequently, the contrastive experiments of the above two OEOs on oscillation modes are carried out. The oscillation mode spacing of 40.32 MHz and 2.137 GHz are obtained. These results show that the SiO OWRR can function as an excellent 'filter' in the minimum loop of the OEO. Moreover, the side mode suppression ratio and the phase noise of the OEO have been improved. Our experimental results demonstrate that the OEO adopting SiO OWRR is feasible to achieve the single-mode oscillation and obtain better performance microwave signals.
单模振荡对于光电振荡器（OEO）的实用性至关重要。由于受到射频（RF）滤波器带宽和精度的限制，基于长光纤延迟线的OEO难以实现单模振荡。因此，本文首次提出将具有高Q值和模式选择特性的SiO光波导环形谐振器（OWRR）应用于OEO，以替代长光纤延迟线。构建了基于最小环路和SiO OWRR的OEO。分别利用MATLAB对最小环路OEO的振荡特性和SiO OWRR的传输特性进行了仿真。通过比较这些仿真结果，从理论上验证了SiO OWRR应用于OEO的滤波效果。随后，对上述两种OEO的振荡模式进行了对比实验。获得了40.32 MHz和2.137 GHz的振荡模式间隔。这些结果表明，SiO OWRR在OEO的最小环路中可作为一种出色的“滤波器”。此外，OEO的边模抑制比和相位噪声也得到了改善。我们的实验结果表明，采用SiO OWRR的OEO实现单模振荡并获得性能更好的微波信号是可行的。
