Band-Notched Ultra-Wideband Bandpass Filter Using Dual-Mode Resonator Loaded Slotline

Abstract

Abstract-In this article, a novel band-notched ultra-wideband (UWB) bandpass filter based on hybrid microstrip/slotline structure is proposed. A quad-mode stubs-loaded slotline resonator is fed by two orthogonal microstrip lines and ultra-wideband bandpass characteristic is excited. A stub-loaded dualmode microstrip resonator is externally loaded to the quad-mode slotline resonator, and a notched band with sharp roll-off characteristic is achieved. The circuit model for the dual-mode microstrip resonator loaded slotline is given and analyzed. The proposed filter is designed and fabricated. Simulated and measured return losses are −12 dB/−18 dB and −18 dB/−10 dB in lower and higher passband. The return loss in the notched band is greater than 15 dB.

A Wide-Beam Circularly Polarized Asymmetric-Microstrip Antenna

“…Stepped impedance resonator was widely used to design bandpass filters and to improve its performance [2][3][4][5]. To reduce the total size of bandpass filters, dual mode resonator has been proposed for the design of this component [6][7][8][9]. To get better performance and to minimize the radiation loss between the fed line and the resonators, bandpass filters using complementary split ring resonators or E-shaped resonators have been designed and fabricated [10,11].…”

Compact bandpass filters based on linked hexagonal‐omega resonators

“…Stepped impedance resonator was widely used to design bandpass filters and to improve its performance . To reduce the total size of bandpass filters, dual mode resonator has been proposed for the design of this component . To get better performance and to minimize the radiation loss between the fed line and the resonators, bandpass filters using complementary split ring resonators or E‐shaped resonators have been designed and fabricated .…”

Design of UWB Bandpass Filter with Notched Band Using Distributed CRLH Transmission Lines

“…Recently, a compact band-notched UWB BPtF with microstrip/slotline ring resonators and microstrip short circuited stubs was presented in Cui et al (2014). A stubs-loaded slotline MMR fed by two microstrip lines achieved a UWB bandpass characteristic and a notched band was created by loading a stub-loaded, dual-mode microstrip resonator to the slotline MMR (Guan et al, 2014). A UWB BPF with hybrid CPW feed-line and microstrip resonator structure was presented and a notched band was realized using a symmetric E-shaped slot-line and etching slots on a microstrip resonator (Zheng et al, 2014).…”

“…The measured group delay varies between 0.28 and 0.65 nsec with a maximum variation of 0.37 nsec over its entire passband. The fabricated UWB BPF is more compact than the example inGuan et al (2014) andZheng et al (2014) and has a simpler structure compared with that ofSong et al (2012),Cui et al (2014),Guan et al…”