Compact QB‐BPF based on single PMR

Abstract

Compact quint-band bandpass filter (QB-BPF) based on a novel pentamode resonator (PMR) is presented. The first five resonant modes of the proposed PMR can be independently controlled by shorted highimpedance section of quarter-wave stepped impedance resonators, and four loaded open stubs resulting in the independency of centre frequencies and quality factors of five passbands. Meanwhile, due to the multipath propagation induced from cross-coupling, 11 transmission zeros are realised around five passbands, resulting in high passband selectivity. As an example, a QB-BPF operating at 0.63/1.2/1.8/2.45/ 3.5 GHz is designed and fabricated. The fabricated QB-BPF also has a compact size of 0.18λ g × 0.12λ g .

Compact metamaterial inspired structure with bandpass characteristics for penta‐band applications using virtual ground concept

“…Multiple passband filters with compact size, low insertion loss, and high selectivity are required in modern wireless communication systems . In recent times, few studies have been published for dual‐band bandpass filters (BPFs), triple‐band BPFs, quad‐band BPFs, and penta‐band BPFs . In Reference , by using short‐circuited stubs and multiple coupled poles, transmission zeros based dual‐band BPF was obtained with high selectivity.…”

“…In Reference , a BPF with five passband responses was designed using a quarter wavelength resonator and multimode resonator along with mixed magnetic and electric coupling. A penta/quint‐band BPF has been proposed with two penta‐mode resonators . Each resonator was formed by four open stubs and λ /4 stepped impedance resonator.…”

“…1 In recent times, few studies have been published for dual-band bandpass filters (BPFs), 2,3 triple-band BPFs, 4,5 quad-band BPFs, 6,7 and penta-band BPFs. [8][9][10][11] In Reference 2, by using short-circuited stubs and multiple coupled poles, transmission zeros based dual-band BPF was obtained with high selectivity. The coplanar waveguide-based dual-band filter has been designed using complementary split ring resonator (CSRR), in which the zeroth-order resonance frequency was controlled by shunt parameters.…”

“…A penta/quint-band BPF has been proposed with two penta-mode resonators. 10 Each resonator was formed by four open stubs and λ/4 stepped impedance resonator. Center frequency of each passband can be controlled independently.…”

Design of Switchable and Reconfigurable Semi-lumped Wideband Bandpass Filter

“…The rapid development of wireless communication technology requires radio frequency (RF) front‐end to be miniature, multifunctional, wideband, and multiband in recent decades. Therefore, microwave bandpass filters (BPFs) with high performance have been widely investigated using various techniques, which include the multi‐mode resonator (MMR) , defected ground structure (DGS) , signal multi‐path propagation , and combining several BPFs using common ports . Owing to its simple structure, flexible regulation, and compact size, MMR is a very promising candidate in filter design.…”