Stub (electronics)

About: Stub (electronics) is a research topic. Over the lifetime, 8172 publications have been published within this topic receiving 75018 citations.

Design of a compact dual-band-notch ultra-wideband bandpass filter based on wave cancellation method

Abstract: In this study, a compact ultra-wideband (UWB) bandpass filter (BPF) with sharp roll-off, improved out-of-band performance and dual-band-notch operation is presented and its design procedure is discussed. In the proposed structure, in order to reject the unwanted harmonic pass bands, a pair of modified cross-shaped coupled lines (CCLs) is implemented along the ports of the filter. Moreover, a pair of half-circle-shaped stubs and a stepped-impedance stub are loaded on the main resonator in order to obtain additional transmission zeros (TZs) which are controllable separately. Implementation of the CCLs and the stub loaded resonator (SLR) reduce the total size of the presented microstrip BPF. Besides, by extending and folding the upper coupled line of each CCLs and also through an open stub which is protruded inside a slot on the main resonator, dual-band-notch operation is added to the performance of the presented filter. The fabricated prototype has a small size and is capable to cover frequency band of 2.8–10.69 GHz with two band-notch functions at 4.9–5.4 and 7.83–8.25 GHz which suppresses the interference between UWB spectrum with wireless local area network (WLAN) and satellite communication frequency bands, respectively. The proposed filter has a compact size while showing good return loss and insertion loss characteristic in the frequency band of interest.

Experimental and numerical studies of concrete-filled high-chromium stainless steel tube (CFHSST) stub columns

Abstract: The present paper reports a thorough experimental and numerical investigation into the compressive behaviour and load-carrying capacities of concrete-filled steel tube (CFST) stub columns with the outer tubes made of a newly developed high-chromium grade EN 1.4420 stainless steel. In comparison with the most commonly used stainless steel grades EN 1.4301 and EN 1.4404, the new grade EN 1.4420 possesses lower material price, but better corrosion resistance and higher strength, and thus has a greater potential for widespread use in composite construction. In this study, an experimental programme was firstly carried out on 15 CFST stub columns with high-chromium stainless steel tubes of five different cross-section sizes and concrete infill of three grades, as well as 5 (reference) bare high-chromium stainless steel tube stub columns. The test setup, procedure and results, including the ultimate loads, load−deformation histories and failure modes, were fully reported. The experimental investigation was supplemented by a numerical modelling study, where the developed finite element models were firstly validated against the experimentally obtained results and then utilised to perform parametric studies for the purpose of expanding the limited test data pool over a wider range of cross-section sizes. The test and numerical results were utilised to evaluate the applicability of the codified provisions, established in North America, Europe and Australia, to the design of the new concrete-filled high-chromium stainless steel tube stub columns. Overall, the examined design codes were generally found to yield safe-sided but slightly conservative resistance predictions for the new high-chromium stainless steel composite stub columns. Modifications to the codified design provisions were then made, and shown to result in an improved level of design accuracy.

L-resonator bandstop filters

Abstract: A design procedure is presented for TEM narrow bandstop filters using L resonators, which are intermediate of the gap- and parallel-coupled resonators typically used, having parallel coupling only over a portion of the resonator length and a grounded end in either the coupled or stub portion of the resonator.

Trapezoid ultra wide band patch antenna

Abstract: A micro-miniature, light weighted and low cost trapezoid ultra wide antenna having an ultra wide band characteristics and a notch characteristic in 5 GHz WLAN band (5.15–5.35 GHz) is disclosed. The trapezoid ultra wide antenna includes: a dielectric substrate; a trapezoid shaped patch formed at an upper end of a middle line on an upper side of the dielectric substrate; a feeding line formed at a bottom end of the middle line on the upper side of the dielectric substrate for feeding electric power to the trapezoid shaped patch; a matching stub formed between the trapezoid shaped patch and the feeding line for impedance matching between the trapezoid shaped patch and the feeding line; and a ground formed at a side of the feeding line on the upper side of the dielectric substrate.

A Survey on Planar Ultra-Wideband Antennas with Band notch Characteristics: Principle, Design, and Applications

Abstract: UWB systems provide a distinctive solution for short-range wireless communication due to large bandwidth and low power consumption in transmission and reception. However, for these systems, designing an antenna with optimal characteristics is a major challenge, because it needs to avoid interference with existing narrowband systems (e.g., WLAN, Wi-MAX, HIPERLAN, ITU-R, etc.) in the UWB spectrum. To achieve this, different techniques (e.g., Slot, parasitic element and stub loading, Using fractals, metamaterials and electromagnetic band gap (EBG) structures) have been reported in the literature and this paper provides a comprehensive review of the mentioned techniques for achieving band notch characteristics in UWB antennas. Moreover, the challenges, future perspectives, simulated and measured results, different notched bands and their applications are also discussed in this paper to make it useful for future research.