The development and measurement of a single layer, wideband, and angularly stable microwave polarization converter (PC), specifically at a low-frequency regime, is still a very challenging task. In this article, a quad resonance, mono-band metamaterial polarization converter is fabricated and measured using a non-destructive free-space microwave measurement setup. A comprehensive study of a single-layer metamaterial (MTM) structure using a miniaturized fractal element array reveals that four resonances can be achieved within its operating frequency band to realize a wide operating band. The proposed MTM-PC is inspired by the split-ring resonator (SRR) based fractal geometry to control the linearly polarized electromagnetic (EM) wave in the C-band. The result shows the average polarization conversion ratio over 87% in a single broad frequency band (i.e., 5.5 GHz to 8.0 GHz). A careful study reveals that wideband response at lower frequency is achieved by introducing four resonances due to fractal inspired SRR geometry. Moreover, the proposed structure is the oblique angle insensitive up to 45°. The results reflect the enormous potential of the proposed approach for various practical EM applications.

单层，宽带和角度稳定的微波极化转换器（PC）的开发和测量，尤其是在低频状态下，仍然是一项非常艰巨的任务。在本文中，使用无损自由空间微波测量装置制造并测量了四谐振单波段超材料偏振转换器。对使用微型分形元素阵​​列的单层超材料（MTM）结构的全面研究表明，可以在其工作频带内实现四个共振，以实现较宽的工作频带。提出的MTM-PC受基于开环谐振器（SRR）的分形几何学的启发，来控制C波段中的线性极化电磁（EM）波。结果显示在单个宽频带（即5.5 GHz至8.0 GHz）中，平均极化转换率超过87％。一项仔细的研究表明，由于分形激发的SRR几何形状，通过引入四个共振，可以实现较低频率的宽带响应。此外，所提出的结构是倾斜角不敏感到45°。结果反映了所提出的方法在各种实际EM应用中的巨大潜力。