This manuscript presents an ultra-wideband (UWB) bandpass filter (BPF) with dual transmission zeros (TZ) embedded in the passband for interference free operation in indoor environment. Based on the vertical electromagnetic (EM) coupling of microstrip-to-coplanar waveguide (CPW) transition, the structure has two similar microstrips placed adjacent on the top plane whereas a short-circuited CPW forms the ground. The response of this BPF is quasi-elliptical in nature with two TZs at either passband edges which enhances selectivity and improves insertion/return loss. To this basic BPF, novel sectoral folded split ring resonator (SFSRR) and spiral resonator (SR) are appended in the slots of the ground plane which produce dual TZs in the passband at 4.5 and 8 GHz respectively. A prototype of the proposed structure is fabricated and tested. The dual notched BPF is developed on a low cost substrate and is of compact size occupying an area of 21.2 × 16 mm².

该手稿介绍了一种超宽带（UWB）带通滤波器（BPF），在通带中嵌入了双传输零点（TZ），可在室内环境下实现无干扰运行。基于微带到共面波导（CPW）过渡的垂直电磁（EM）耦合，该结构在顶面上相邻放置了两个类似的微带，而短路的CPW形成了地面。该BPF的响应本质上是准椭圆形，在两个通带边缘处都有两个TZ，从而提高了选择性并改善了插入/回波损耗。在此基本的BPF上，将新颖的扇形折叠裂环谐振器（SFSRR）和螺旋谐振器（SR）附加在接地层的插槽中，分别在通带中以4.5 GHz和8 GHz的频率产生双TZ。拟议结构的原型已制造并经过测试。²。