MATERIALS Wireless Bandpass Filters Build on Metamaterials These second- and third-order bandpass filters leverage metamaterial resonators for low passband insertion loss and high out-of-band rejection for wireless applications at 2.4 GHz. Ahmed A. Ibrahim, Mahmoud A. Abdalla, Adel B. Abdel-Rahman 1 | May 18, 2018 Download this article in PDF format. Microwave bandpass filters (BPFs) are essential for maintaining separate channels in wireless communications systems. As such systems become more compact, BPFs must meet more demanding requirements for smaller size, lower insertion loss, higher out-of-band rejection (selectivity), and lower cost. Several techniques are used to design microwave BPFs,1-4 although the authors have developed an approach […]