Design Filters Using Tunable E-Shaped Dual-Mode Resonators for Lower-Ultra-Wideband and Upper-Ultra-Wideband Applications

Abstract

Abstract-Two ultra-wideband (UWB) microstrip bandpass filters (BPFs) are proposed by using tunable E-shaped dual-mode microstrip Stepped-Impedance Resonator (SIR). For the lower band filter measurement results show there is a passband of 3.1 GHz to 5.2 GHz and its 3 dB fractional bandwidth is 51%. The UWB upper band filter may be obtained by tuning E-shaped SIR. The measurement results show there is a passband of 6 GHz to 10.6 GHz and its 3 dB fractional bandwidth is 55%. Compared with the similar investigation using the cascade of electromagnetic band gap (EBG)-embedded multiple-mode resonator (MMR) and fork resonator, the proposed approach has some advantages, such as easier adjustment of bandwidths, better passband performances and smaller size etc..

UWB bandpass filter with quad‐notched bands using arrow‐shaped resonators

“…Several techniques for band‐notched filter design have been presented in recent years. The proposed notched filters include the introduction of additional resonators , embedded open stubs , and asymmetric coupled fed lines . Additional resonators are placed close to main transmission to get notched transmission response by using both electric couplings and magnetic couplings.…”

“…A main transmission line is electrically coupled to half‐wavelength resonators or is magnetically coupled to half‐wavelength resonators in a hairpin shape for designing band‐notched filters have been reported in . L‐shaped resonance and E‐shaped resonance have also been used to design narrow stopband filter.…”

Design of Compact UWB Bandpass Filter with Sharp Rejection Characteristics

“…A Bandpass Filter (BPF) is an essential component in an UWB system and UWB BPFs have thus been studied widely. Many filters have been designed using microstrip lines (Gao et al, 2008;Duong and Kim, 2009;Watanabe et al, 2009;Wu et al, 2013) and a combination of microstrip lines and coplanar structures (Kuo et al, 2007;Chen et al, 2009), as well as ones with a combination of microstrip lines and defected ground structures (Huang et al, 2010;Tian and Chu, 2011;Gao et al, 2012;Kumar and Upadhayay, 2012). Some have been implemented using Composite Right/Left-Handed (CRLH) Transmission Lines (TLs) (Lin et al, 2007;Gong and Chu, 2008;Shen and Law, 2012;Su et al, 2012) Size reduction and bandwidth enhancement of bandpass filters can be achieved with the use of CRLH TLs (Lai et al, 2004).…”

Two Kinds of Dual-Band Bandpass Filter Based on a Single Square Ring Resonator

“…Many reports about various dualband bandpass filters (BPFs) have been published [1][2][3][4][5][6]. Among them, some dual-band BPFs are realized by employing two sets of resonators with different resonant frequencies [1][2][3], of which at least two resonators are needed and the filters occupy a large circuit size.…”

“…Among them, some dual-band BPFs are realized by employing two sets of resonators with different resonant frequencies [1][2][3], of which at least two resonators are needed and the filters occupy a large circuit size. The stepped impedance resonators (SIRs) and stub loaded resonators (SLRs) are also employed for dual-band operation [4][5][6], and at least two resonators are required. Other methods such as, defected ground structure (DGS) [7,8], shorted-ended dual-mode resonator (SEDMR) [9], coupled line resonator [10], and low temperature cofired ceramic (LTCC) [11] have also been proposed for dual-band applications.…”