A microwave photonic phase shifter based on four cascaded tunable silicon nitride microring resonators is proposed. The phase shifts and RF power variations of the microwave photonic phase shifter were investigated theoretically and experimentally. Good overall performances with full phase tuning range of 400°, low RF power variations of ± 1.5 dB with a broad bandwidth of 11 GHz, fiber to fiber insertion loss about 5.2 dB were achieved. The maximum frequency can be extended to about 40 GHz, which is limited by the MRR’s free spectra range.

中文翻译：

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基于级联氮化硅微环的高性能微波光子移相器

提出了一种基于四个级联可调氮化硅微环谐振器的微波光子移相器。从理论上和实验上研究了微波光子移相器的相移和射频功率变化。具有 400° 的全相位调谐范围、± 1.5 dB 的低射频功率变化和 11 GHz 的宽带宽以及约 5.2 dB 的光纤到光纤插入损耗，实现了良好的整体性能。最大频率可以扩展到大约 40 GHz，这受到 MRR 的自由光谱范围的限制。