Stub (electronics)

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

Ultra-Compact Reconfigurable Band Reject UWB MIMO Antenna with Four Radiators

Abstract: A compact reconfigurable UWB MIMO antenna with four radiators that accomplish on-demand band rejection from 4.9 to 6.3 GHz is presented. An LC stub is connected to the ground plane by activating the PIN diode for each radiator. Two radiators are placed perpendicular to each other to exploit the polarization diversity on a compact 25 × 50 mm 2 FR4 laminate. Two additional radiators are then fixed obliquely on the same laminate (without increasing size) in angular configuration at ±45 ∘ perpendicular to the first two planar radiators still exploiting polarization diversity. The design is validated by prototyping and comparing the results with the simulated ones. On demand band rejection through the use of PIN diodes, wide impedance matching (2–12 GHz), high isolation amongst the radiators, compactness achieved by angular placement of the radiators, low gain variation over the entire bandwidth, band rejection control achieved by adjusting the gap between stub and ground plane, and low TARC values makes the proposed design very suitable for commercial handheld devices (i.e., Huawei E5785 and Netgear 815S housings). The proposed configuration of the UWB MIMO radiators has been investigated first time as per authors’ knowledge.

Design and Analysis of ź-Shaped UWB Antenna with Dual Band Notched Characteristics

Abstract: This manuscript presents, a compact dual band notched ź-shaped ultrawideband (UWB) monopole antenna. The antenna consists of a ź-shaped radiating patch loaded with the ź-shaped and inverted C-shaped slots. By properly optimizing the shape parameters of the ź-shaped slot and the inverted C-shaped slot along with the rectangular stub, dual band notched characteristics for Worldwide Interoperability for Microwave Access (3.3---3.8 GHz) and Wireless Local Area Network (5.15---5.825 GHz) is achieved, respectively. An equivalent RLC resonant circuit is proposed for the dual band notched characteristics of the antenna which is based on the current distribution and the input impedance characteristics of the antenna. The simulated and measured values of the VSWR and the input impedance characteristics are also compared with the values obtained from the equivalent circuit analysis. The simulated and measured results show that the proposed antenna has 2.5---11.5 GHz (about 129 % fractional bandwidth) operational impedance bandwidth (VSWR < 2) with dual band notched characteristics, stable radiation patterns, and good time domain characteristics which are essential for the UWB applications.

Slot embedded dual-band patch antenna for WLAN and WiMAX applications

Abstract: A dual-band, singly fed slotted microstrip antenna for the 2.4 GHz wireless local area network (WLAN) and 2.5/3.5 GHz worldwide interoperability for microwave access (WiMAX) is implemented. The antenna consists of an aperture-fed square patch embedded with a narrow and symmetrical π-shaped slot to generate dual-band resonance. The geometry resonates at a lower frequency band which fully covers the 2.4–2.484 GHz WLAN band and 2.5–2.69 GHz WiMAX band. The higher-frequency resonance is obtained in the 3.5 GHz WiMAX band. An oval-shaped stub at the open end of the single microstrip feed line is used to obtain impedance matching over a wide band of frequencies. The 10 dB return loss bandwidth measured for the antenna is 18.07 and 8.28% in the lower and upper bands, respectively. Reactive loading of the patch with the π-shaped slot has resulted in a reduction of patch size by 36% when compared with a traditional square patch resonating at an operating frequency of 2.4 GHz.

Printed circuit board

Abstract: Printed circuit board in which deterioration of signal transmission characteristics otherwise caused by a stub parasitically formed in a through-hole is suppressed to provide optimum high-speed signal transmission characteristics. A printed circuit board 10 includes a power supply/ground layer 11 and a signal line 12 b in a dielectric layer 13 , and a through-hole 12 connected to the signal line 12 b . A clearance 14 which becomes an anti-pad is provided in an area between the through-hole 12 and the power supply/ground layer 11 . The signal line 12 b is extended from the through-hole 12 through the clearance 14 to an area below the power supply/ground layer 11 . The portion of the signal line 12 b arranged in the vicinity of the power supply/ground layer 11 in the clearance 14 has an area of impedance gradient 17 whose characteristic impedance becomes progressively lower in a direction away from the through-hole 12.

Octagonal nut shaped monopole UWB antenna with sextuple band notched characteristics

Abstract: A printed octagonal nut shaped ultra-wideband (UWB) monopole antenna with sextuple band rejection characteristics is proposed and investigated. Improved frequency selectivity of the rejection bands can be achieved by employing hook shaped, split P-shaped open ended stub resonators along with open ended meandered slot resonator pair, Meandered T shaped stub, rectangular dual split ring conductor backed plane and spiral shaped defective ground structure exhibit band rejection of 3.3-3.64 GHz (9.79 %), 5.1-5.35 GHz (4.97%), 5.62-5.96 GHz (5.87%), 7.28-7.68 GHz (5.21%), 7.8-8.21 GHz (5.12%) and 9.23-9.77 GHz (5.68%) to mitigate the possible interferences of WiMAX, lower WLAN, upper WLAN, X-band satellite downlink, ITU-8 GHz and radio navigation (RN) band. Sharpness and the tuning of the individual notched band can be easily controlled by adjusting the dimension of the corresponding band notched element. Besides, a lumped element equivalent circuit model has been evaluated by comparing with the response of proposed band notched UWB antenna that exhibits highly selective rejection bands. Moreover, radiation patterns, peak gain and time domain behavior of the proposed antenna are also investigated to assess its suitability in UWB communication.