Stub (electronics)

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

Dual-band equal/unequal wilkinson power dividers based on coupled-line section with short-circuited stub

Abstract: This paper presents dual-band equal/unequal Wilkinson power dividers based on a coupled-line section with short-circuited stub (called as the \coupled-line section" for short), which consists of a pair of parallel coupled lines and a short-circuited stub. With the analyses of the phase shift and equivalent characteristic impedance, the coupled-line section is used to replace the quarter-wavelength branch line in the conventional equal/unequal Wilkinson power divider to obtain excellent dual-band operation. The closed-form equations and design procedures of dual-band Wilkinson power divider are given, where one degree of design freedom is obtained and design ∞exibility is shown. As two examples, a dual-band equal Wilkinson power divider with the frequency ratio of 1:8 : 1 and an unequal one with the high power dividing ratio of 7 : 1 and frequency ratio of 1:8 : 1 are designed, fabricated and measured. The measurements are in good agreement with the simulations. It is shown that the proposed power dividers have simple topologies, and can be easily fabricated with small frequency ratios and high power dividing ratios.

Compact dual-band bandpass filter using folded sir with two stubs for wlan

Abstract: A novel compact dual-band bandpass fllter using tri- section stepped impedance resonators (SIRs) is presented for Wireless Local Area Network (WLAN). SIRs and one stub between parallel couple line are employed to realize two satisfactory passbands. Meanwhile, one transmission zero is generated between the two passbands to achieve a high out-of-band rejection. Simulated results show that two central frequencies are located at desired 2.4 and 5.2GHz with 3dB fractional bandwidths of 6.3% and 3.4% respectively. The measured results are in good agreement with the simulated ones.

Fabrication or repair technique for integrally bladed rotor assembly

Abstract: Techniques for fabricating or repairing integrally bladed rotors are developed. A new or replacement blade is bonded to a projecting stub. The new blade has a collar through which bonding forces are transmitted. After bonding with heat and pressure, final machining and heat treatment operations are performed.

Material properties and structural behavior of cold-formed steel elliptical hollow section stub columns

Abstract: Material properties, residual stress distributions and cross-sectional behavior of cold-formed steel elliptical hollow sections are investigated in this study. Four cross-section series with the nominal section aspect ratio ranging from 1.65 to 3 were included in the experimental investigation. The material properties for each cross-section series and material properties distribution on half of the cross-section profile of a representative section were measured through tensile coupon tests. The distributions of bending and membrane residual stresses in both longitudinal and transverse directions were measured on the half-section profile of the same representative section. Initial local geometric imperfections were measured on five stub column specimens. Besides, stub column tests were conducted between fixed ends to ascertain the material properties of the complete cross-section in the cold-worked state as well as to study the structural behavior of cold-formed steel elliptical hollow section stub columns. In addition to experimental investigation, a finite element model was developed and verified against the test results, with which an extensive parametric study covering a broad range of cross-section geometries was carried out. Currently, there is no codified design rule for elliptical hollow section compression members. The stub column strengths obtained from experimental program and numerical analysis were only compared with the predicted strengths by the equivalent diameter method and equivalent rectangular hollow section approach proposed by previous researchers for design of hot-finished steel elliptical hollow sections, the existing traditional design rules originally developed for circular hollow section with equivalent diameter incorporated as well as the Direct Strength Method and the Continuous Strength Method that the equations were not calibrated for cold-formed steel elliptical hollow sections. The comparisons show that the Direct Strength Method offers the most accurate and reliable design strength predictions among the existing design methods, but further improvement remains possible. In this study, modifications on the Direct Strength Method and the Continuous Strength Method are proposed, which are shown to improve the accuracy of the design strength predictions.