Triple Band Notch Research Articles

DUAL AND TRI-BAND-NOTCHED ULTRAWIDEBAND (UWB) ANTENNAS USING COMPACT COMPOSITE RESONATORS

An ultra-wideband (UWB) antenna with triple band- notched characteristics is presented in this paper. The triple-notched bands (5.15{5.35GHz and 5.725{5.825GHz for WLAN, 7.9{8.395GHz for X-band) are achieved by using only one novel composite resonator with multiple resonant characteristics. The resonator is placed on the back surface of the substrate and connected to the radiation patch through one via-hole. An equivalent circuit model is built for analyzing the band-notched characteristics. Moreover, the notched bands can be adjusted independently, and the resonator structure is very compact.

Compact UWB BPF with triple‐notched bands based on stub loaded resonator

A compact ultra-wideband (UWB) bandpass filter (BPF) with triple-notched bands and wide stopband is presented. The basic UWB BPF comprises four folded shunt quarter-wavelength short-circuited stubs separated by connecting lines with lengths of λg0/4 and λg0/2, respectively. The proposed coupled triple-mode stub loaded resonator is found to have the advantage of introducing triple-notched bands simultaneously. Five stepped-impedance shunt stubs are chosen to suppress the harmonic passband. The predicted results are compared with measured data and good agreement is reported.

Compact UWB Bandpass Filter With Triple-Notched Bands Using Triple-mode Stepped Impedance Resonator

In this letter, a compact ultra-wideband (UWB) band-pass filter (BPF) with triple-notched bands is presented using a novel triple-mode stepped impedance resonator (SIR). The basic UWB BPF is comprised of four folded shunt quarter-wavelength short-circuited stubs separated by connecting lines with length of λ <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">g0</sub> /4 and λ <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">g0</sub> /2, respectively. The proposed coupled triple-mode SIR is found to have the advantages of introducing triple-notched bands and providing higher degree of freedom to adjust the resonant frequencies. The simulated and measured results are in good agreement with each other, showing good wideband filtering performance with sharp rejection skirts outside the passband.

TRIPLE BAND-NOTCHED PLANAR UWB ANTENNA USING PARASITIC STRIPS

A compact planar ultra-wideband (UWB) antenna with triple band notch characteristics is proposed in this paper. The antenna consist a rectangular radiating patch, a modifled partial ground plane, and has an overall dimension of 30 £ 22mm 2 . Three resonant elements are placed above the ground plane to generate three notch frequency bands separately in the WiMAX, the lower WLAN and the upper WLAN frequency bands. The proposed antennas are successfully simulated, prototyped and measured. Efiects of the key deign parameters on band notch characteristics are also investigated. The realized antenna achieved an operating bandwidth (VSWR • 2) ranges from 2.9 to more than 11GHz with triple notched bands of 3.26{ 3.71 (12.9%), 5.15{5.37 (8.5%), and 5.78{5.95 (2.9%)GHz. Measured ∞at transfer function and constant group delay within the operating band except notched bands make the proposed antenna suitable for being used in practical UWB applications.

CPW-fed ultra-wideband antenna with triple-band notch function

Proposed is the design strategy for the triple-band notched ultra-wideband (UWB) antenna emphasising the rejection characteristic at 3.5/5.5/8.2 GHz bands. The essence of the design strategy is embedding the three notching elements onto the primitive antenna to serve as respective stop band filters. On embedding, the hot issue is how to minimise the level of cross-coupling among the three elements because no coupling leads to set its distinct stop bands orthogonally. Owing to the complete unmatched appearances in shapes and the optimised arrangement of elements, they are least of all in the coupling and thus the proposed antenna can be engineered to operate at specific frequencies. Measured results show the validity of the suggested design strategy.

Ultra-Wideband Bandpass Filter With Multiple Notch Bands Using Nonuniform Periodical Slotted Ground Structure

A novel ultra-wideband (UWB) bandpass filter that is capable of integrating multiple notch bands is proposed in this paper. A multilayer nonuniform periodical structure, which can generate multiple transmission zeros, is deployed in the filter design to improve the selectivity and upper stopband performance of the filter. Short-circuited stub resonators are then integrated to obtain multiple notch bands. The compact footprint of the filter is achieved. UWB filters of this type without a notch and with single-, double-, and triple-notch bands are designed to meet the Federal Communications Commission-defined UWB indoor limit. The designed filters are verified by experiments and fabricated by using multilayer liquid-crystal polymer lamination technology. Both full-wave simulated and measured results are presented and good agreement between them is observed. The proposed filter has good performance and is attractive for UWB communication and radar systems.

Ultra-wideband bandpass filter with multiple notch-bands on multilayer liquid crystal polymer substrate

Novel compact ultra-wideband (UWB) bandpass filters (BPFs) with single or multiple notch-bands to avoid interference from existing radio systems are presented. A compact UWB BPF is proposed and designed based on broadside-coupled stepped impedance resonators (SIRs) at first, and then notch-bands are generated by embedding open-circuit stubs into broadside-coupled SIRs. Because of the harmonic suppression behaviour of SIRs, the proposed UWB BPFs have a wide stopband and high rejection level. The characteristic of the proposed notch-structure was investigated by full-wave simulations. Multilayer liquid crystal polymer (LCP) technology was used to implement the designed UWB BPFs. In the experiments, a UWB BPF with excellent stopband performance was designed to meet the Federal communications commission-defined indoor limits at first, and then UWB BPFs with single, double and triple notch-bands were designed to demonstrate the flexible notch-band, high-selectivity and wideband harmonic suppression performances of the proposed filter. The designed BPFs were fabricated by a multilayer LCP lamination process and measured using a vector network analyser. Good agreement between the predicted and measured results was obtained as presented here.