In this work, we report a Micro-Electro-Mechanical System (MEMS)-Semiconductor Optical Amplifier (SOA) active interferometer as a low cost and miniaturized tunable broadband sliced source and optical loss auto-equalizer for single pass band microwave photonic filter (MPF). A low finesse Fabry-Perot MEMS interferometer is formed from a movable deeply etched micro-mirror in front of a cleaved fiber facet. The interferometer slices the amplified spontaneous emission (ASE) output of the SOA, while the output is feedback to the SOA again for amplification and optical loss auto-equalization through the SOA gain saturation effect. This configuration improved the uniformity of the MPF passband attenuation along the tuning range down to 3.72 dB only. The filter center frequency can be finely tuned electrically for ±241.6 MHz with a MEMS electrostatic comb actuator driving the mirror. The center frequency is controlled by the distance between fiber facet and micro-mirror. The operation of the proposed MEMS-SOA based MPF is experimentally verified as a proof of concept from 1.2 to 4.5 GHz and can be easily extended to higher frequencies. A tuning resolution of 6.04 MHz/ $\mu \text{m}$ is achieved with stopband attenuation larger than 20 dB and 3-dB bandwidth mean value of 141 MHz.

中文翻译：

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支持均匀可调微波光子滤波器的 MEMS-SOA 频谱切片自动均衡源

在这项工作中，我们报告了一种微机电系统 (MEMS)-半导体光放大器 (SOA) 有源干涉仪，它是一种低成本、小型化的可调谐宽带切片源和用于单通带微波光子滤波器 (MPF) 的光损耗自动均衡器）。低精细度的 Fabry-Perot MEMS 干涉仪由可移动的深度蚀刻微镜在切割的光纤端面前形成。干涉仪对 SOA 的放大自发辐射 (ASE) 输出进行切片，而输出再次反馈到 SOA，通过 SOA 增益饱和效应进行放大和光损耗自动均衡。这种配置将 MPF 通带衰减沿调谐范围的均匀性提高到仅 3.72 dB。滤波器中心频率可以在±241 范围内进行电微调。6 MHz 使用 MEMS 静电梳状执行器驱动反射镜。中心频率由光纤面与微镜之间的距离控制。所提出的基于 MEMS-SOA 的 MPF 的操作经过实验验证，作为从 1.2 到 4.5 GHz 的概念证明，并且可以轻松扩展到更高的频率。在阻带衰减大于 20 dB 和 3-dB 带宽平均值为 141 MHz 的情况下实现了 6.04 MHz/ $\mu \text{m}$ 的调谐分辨率。