Stub (electronics)

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

Compact Dual-Band Filter Using Open/Short Stub Loaded Stepped Impedance Resonators (OSLSIRs/SSLSIRs)

Abstract: A novel microstrip dual-band filter with high frequency selectivity and extended rejection band is reported in this letter. The proposed filter employs one pair of open stub loaded stepped impedance resonators (OSLSIRs) functioning at two frequencies of interest. Two short stub loaded stepped impedance resonators (SSLSIRs) are embedded between the coupled OSLSIRs to generate quasi-elliptic response at two diverse frequencies. Contributed by the 0° feed structure, extra transmission zeros are produced to enhance the out-of-band rejection. OSLSIRs/SSLSIRs are chosen to achieve desired in-band performance and misaligned harmonic frequencies simultaneously. To demonstrate the efficacy of the design concept, a dual-band filter centering at 1.63 and 2.73 GHz is implemented. The design methodology and measured results are presented.

A Low-Profile Broadband 32-Slot Continuous Transverse Stub Array for Backhaul Applications in $E$ -Band

Abstract: A high-gain, broadband, and low-profile continuous transverse stub antenna array is presented in E-band. This array comprises 32 long slots excited in parallel by a uniform corporate parallel-plate-waveguide beamforming network combined to a pillbox coupler. The radiating slots and the corporate feed network are built in aluminum whereas the pillbox coupler and its focal source are fabricated in printed circuit board technology. Specific transitions have been designed to combine both fabrication technologies. The design, fabrication, and measurement results are detailed, and a simple design methodology is proposed. The antenna is well matched ( $S_{11} dB) between 71 and 86 GHz, and an excellent agreement is found between simulations and measurements, thus validating the proposed design. The antenna gain is higher than 29.3 dBi over the entire bandwidth, with a peak gain of 30.8 dBi at 82.25 GHz, and a beam having roughly the same half-power beamwidth in E- and H-planes. This antenna architecture is considered as an innovative solution for long-distance millimeter-waves telecommunication applications such as fifth-generation backhauling in E-band.

Triband vehicle antenna

Abstract: An antenna for simultaneous connection to a citizen's band transceiver, an AM receiver and a FM receiver, particularly suitable for use on a vehicle such as an automobile. The antenna proper is a center-loaded upstanding rod which, in the preferred form, telescopes downwardly to a retracted position where it does not protrude above the ground plane. The antenna proper is connected to a T-connected open stub transmission line and to a FM resonant relatively high impedance signal-carrying transmission line. The former has inductive reactance in the FM band which offsets the capacitive reactance of the relatively short effective length of the antenna proper in the FM frequencies. The signal-carrying transmission line is substantially half wave in length in the FM band so as to reflect impedance at its far end substantially equal to the impedance present at the T-connection. The signal-carrying transmission line is also of length that provides resonant action transforming the relatively low impedance at the T-connection or base of the antenna in the CB band to a higher impedance, such as 50 ohms, at the end of that transmission line. Finally, the signal-carrying transmission line, because of its relatively high characteristic impedance, has very low capacitance and therefore does not tend to load the AM radio. The end of the signal-carrying transmission line is connected to the input terminal of splitter containing resonant circuits which are in turn connected to two transmission lines, one leading to the CB transceiver and the other leading to the AM/FM radio.

Enhanced Matching and Vialess Decoupling of Nearby Patch Antennas for MIMO System

Abstract: Simultaneous improvement of matching and isolation for a modified two-element microstrip patch antenna array is proposed. Two simple patch antennas in a linear array structure are designed, whereas the impedance matching and isolation are improved without using any conventional matching networks. The presented low-profile multifunctional vialess structure comprises only two narrow T-shaped stubs connected to feedlines, a narrow rectangular stub between them, and a narrow rectangular slot on the ground plane. This design provides a simple, compact structure with low mutual coupling, low cost, and no adverse effects on the radiation and resonance. To validate the design, a compact, very closely spaced antenna array prototype is fabricated at 5.5 GHz that is suitable for multiple-input–multiple-output systems. The measured and simulated results are in good agreement with 16 and 40 dB of improvements in the matching and isolation, respectively.

A Flexible and Pattern Reconfigurable Antenna with Small Dimensions and Simple Layout for Wireless Communication Systems Operating over 1.65–2.51 GHz

Abstract: This research article proposes a compact frequency and pattern reconfigurable flexible antenna for heterogeneous applications. A triangular monopole antenna with a semicircular stub is made frequency and pattern tunable by connecting and disconnecting two inverted L-shaped stubs utilizing diodes. When either of the stubs is connected to the radiator, a relative phase difference happens at both ends of the radiator that changes the direction of the electromagnetic radiations, consequently pattern reconfigurability can be obtain. Besides that, because of the reactive load introduced by the stubs, the antenna’s effective length has changed and, as a result, the frequency reconfigurability can be attained. The antenna features a compact size of 40 × 50 × 0.254 mm3 corresponding to 0.22λo × 0.27λo × 0.001λo, where λo is free-space wavelength at 1.65 GHz, while its operational bandwidth is from 1.65 GHz to 2.51 GHz, with an average gain and radiation efficiency of better than 2.2 dBi and 80%, exhibiting a pattern reconfigurability of 180° in the E-plane. The frequency of the proposed antenna can be switched from 2.1 GHz to 1.8 GHz by switching the state of both diodes in OFF and ON-state, respectively. The fabricated prototype of the antenna is tested to verify its performance parameters. In addition, to validate the proposed design, it has been compared with prior arts in terms of the overall size, reconfigurability type, flexibility, radio frequency (RF) switch type used for reconfigurability, and frequency bandwidth. The proposed antenna provides smaller size with a large bandwidth coverage alongside with discrete RF switch type with the advantages of flexibility and both frequency and pattern reconfigurability. As a result, the proposed compact flexible and pattern reconfigurable antenna is a promising candidate for heterogeneous applications, including the global system for mobile (GSM) band (1800 and 1900 MHz) and industrial, scientific and medical (ISM) band (2.4 GHz) along with well-known cellular communication bands of 3G, 4G, and long term evolution (LTE) bands ranging from 1700–2300 MHz around the globe.