Stub (electronics)

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

Tunable Phase Shifter Based on Few-Layer Graphene Flakes

Abstract: This letter presents a voltage-controlled tunable phase shifter based on few-layer graphene. The phase shifter consists of a stub-loaded line, composed of a microstrip line with a stub attached to it through a taper and graphene pad. The bias voltage applied to the graphene pad determines a variation of graphene resistance, which eventually causes the phase change. Without any voltage bias, graphene exhibits high resistance, thus isolating the stub and leading to a low phase shift. As the bias voltage is increased, graphene resistance is lowered, the effect of the stub is more pronounced, and the phase shift is increased. A prototype operating in the frequency range from 5 to 6 GHz has been designed and tested. The measured maximum phase shift obtained is 40°, and the corresponding degradation of the insertion loss is 3 dB.

Method and system for reducing via stub resonance

Abstract: Reducing via stub resonance in printed circuit boards. In one aspect, a method for reducing via stub resonance in a circuit board includes determining that resonance exists for a signal to be transmitted through a signal via extending across a plurality of layers in the circuit board. The resonance is caused by a via stub of the signal via, the via stub extending past a layer connected to the signal via. A location is determined for a ground via to be placed relative to the signal via, the location of the ground via being determined based on reducing the resonance for the signal to be transmitted in the signal via.

Compact Butler matrix using composite right/left handed transmission line

Abstract: A novel composite right/left handed transmission line (CRLH TL) is proposed, for the first time using the Wunderlich-shaped dentiform capacitor and meandered-line short-circuited stub inductor (SSI). The CRLH TL features a larger value of CL and in turn a lower resonance relative to the previous one employing an interdigital capacitor and an SSI. The unique feature of the CRLH TL is applied to engineer a compact Butler matrix. Consistent numerical and measurement results of the matrix prototype centred at 1.8 GHz are shown. The Butler matrix with comparable performance is only 45 of the area that a conventional matrix occupies and can easily facilitate a planar integrated circuit.

New class of microstrip miniaturised filter using triangular stub

Abstract: A new class of compact microstrip filter loaded with a low-characteristic impedance triangular stub is introduced. The respective filter upper stopband selectivity is improved. Without the presence of cross-coupling between non-adjacent resonators, one transmission zero is observed. Frequency tuning can easily be achieved by adjusting the reactance of the stub.

A Multipurpose and Highly-Compact Plasmonic Filter Based on Metal-Insulator-Metal Waveguides

Abstract: A multipurpose and ultra-compact nanoplasmonic wavelength filter based on stub structure in a metal-insulator-metal (MIM) waveguide is suggested and numerically investigated. A novel approach of connecting two stepped-like apertures to both input and output ports is applied to form Fabry-Perot (FP) cavities, which enabled the structure to act as a dual band-pass filter at wavelengths 1310 nm and 1550 nm. It is shown that the variation in cavities’ length allows to realize a long-wavelength cutoff filter, and cutoff wavelength can be easily tuned by adjusting the length of the cavities. Furthermore, it is revealed that increasing the gap between the stepped-like apertures and the cavities provides a triple band-pass at telecom wavelengths, e.g., 1267.5 nm, 1414.19 nm, and 1644.7 nm. The tunable broadband high-pass wavelength filter is then achieved while the lengths of stepped-like apertures and stub resonators are set to be identical. Finally, a tunable nearly perfect absorber can be obtained by varying the width of stub resonators. Therefore, because of functionality, size, as well as efficiency the proposed plasmonic filter may greatly contribute to miniaturization of next generation of photonic integrated circuits (PICs), and find applications in on-chip integration and wavelength-division multiplexing (WDM) in optical communication systems.