This paper presents a tunable bandstop filter design using defected ground structure (DGS) where FR4 substrate is used as a low cost solution compared to others substrate such as Teflon and Rogers RT/Duroid. Thus, the performance of the tunable DGS bandstop filter using FR4 substrate is analyzed in this paper. Besides, analytical modeling of the tunable bandstop filter is derived and discussed ...

The design, fabrication and measured characteristics of micromachined FabryPerot (F-P) optical filters for the visible spectral range are presented. Silver films of 40-50 nm thickness, evaporated on a 300 nm thick low-stress silicon nitride membrane, are used as high-quality mirrors. Two parallel mirrors, with a square aperture of up to 2x2 mm and initial cavity gap of 1.2 μm, form a tunable Fa...

Parametrically tunable audio equalizers are conventionally realized using allpass digital filter networks. They consist of first-order shelving filters and second-order equalizing filters. In this paper, ladder wave digital filters (WDFs) with parametrically tunable coefficients are proposed as shelving and equalizing filters. Similar to the allpass realization, the transfer function power comp...

High linear notch filter Acoustic Wave (SAW) Notch Filter designed to All specifications are based on the TriQuint schematic for the main reference design. ADS Simulation of a third order capacitive coupled tunable bandpass filter. Third Order Shunt Resonator C-Coupled Filter Schematic (based on topology. Bandpass filters are useful for the RTL-SDR as often strong out of band signals can cause ...

We demonstrate theoretically that the periodic multilayer Epoxy/Glass supports acoustic frequency bands sensitive to the changes of temperature. Due to the strong variation of the sound velocity in the Epoxy, the width of the band gaps and the midgap frequencies descend when the temperature passes from 0 to 100°C. The transmittance spectrum shows that this system can be useful as a sound filter...

This paper presents a new concept to implement a tunable filter metamaterial with dual negative refraction composed of ferrite slabs and metallic resonators, including split-ring resonators (SRR), and short wire pairs. The ferrite slabs under an applied magnetics bias provide one magnetic resonance frequency band and the metallic resonators provide another one. The continuous wires within the m...

We propose, design, and experimentally test a non-Hermitian acoustic superlattice that acts as tunable precise filter. The is composed of two concatenated sublattices. first sublattice Hermitian, while the other can be adjusted to Hermitian or non-Hermitian. existence non-Hermiticity, in terms an induced loss second sublattice, results generation absorption resonances appear reflected spectrum....

Takashi Kawamura, Hiroshi Shimotahira, Akihito Otani [Summary] Rapid progress in millimeter-wave wireless communication technologies requires accurate spectrum analysis in the frequency domain over 100 GHz. A tunable preselection filter is a key device in building such a spectrum analyzer. This paper proposes a new tunable filter as a preselector in the frequency range from 110 to 140 GHz. The ...

A tunable eye-opening lattice filter for dispersion compensation is demonstrated on an ultra low-loss waveguide platform based on a compact high-aspect ratio Si3N4 core. A programmable 10th order lattice filter is demonstrated by cascading a total of 21 Mach-Zehnder interferometers with programmable delay lines of lengths designed at the baseband data rate. The filter has ...

In this paper, we propose a method that can be used for image texture recognition in the presence of concurrent rotation and scale changes with tunable directional bandpass Gabor filter banks. The method relies on the analysis of the frequency spectra of the image textures, and from which the rotation and scale changes are estimated using a new spectral shift measure. Tunable Gabor filter banks...