The group delay of passband window plays an important role in the wireless system. Here we propose a controllable group delay structure based on the multimode electromagnetically induced transparency in a closed waveguide system, which is realized by trapping three “dark” modes with high Q‐factors into one “bright” mode with low Q‐factor. Three transparent windows with three discrete peaks of group delay are obtained, whose bandwidth can be adjusted by changing the Q‐factor of each “dark” mode, and then the controllable group delay can be further achieved. Three samples with different distributions of group delay are fabricated and tested. Good agreement between simulated and measured results are presented. The proposed method and structures contribute to the design of passive radio frequency identification (RFID) tags, sensors, multimode filters, slow light components, and novel group‐delay modulator.

中文翻译：

---

基于多模电磁感应透明度的群时延调制

通带窗口的群时延在无线系统中起着重要的作用。在这里，我们提出了一种基于多模式电磁感应的透明性的可控群延迟结构，该透明性是在封闭波导系统中实现的，该结构是通过将三个具有高Q因子的“暗”模式捕获为一个具有低Q因子的“亮”模式来实现的。获得具有三个离散的群延迟峰的透明窗口，可以通过更改每个“暗”模式的Q因子来调整其带宽，然后可以进一步实现可控的群延迟。制作并测试了具有不同群时延分布的三个样本。模拟结果和测量结果之间的一致性很好。所提出的方法和结构有助于无源射频识别（RFID）标签，传感器，多模滤波器，