— In this paper, the ultra-wideband (UWB) bandpass filter (BPF) with a wide stopband is presented. The prototype of proposed UWB BPF is by bending the five short-circuited stubs and coupling the I/O feed lines. In order to have a wide stopband, an bandstop structure embedded in input/output (I/O) lines without degrading the passband performances is used. The measured results verified that by us...

We propose and demonstrate, based on the concept of a microwave bandstop filter, two quantum wave bandstop filter structures. Both structures employ nanoscale gates in a heterojunction transistor to induce a quantum cavity connected by two one-dimensional wires. As the electron wavelength is changed by the gate voltage, we observed that, at certain gate voltages, the transmission of electron wa...

This paper discusses two new designs of reconfigurable perfectly-matched bandstop filter which is based on L-shape and ring resonator. The perfectly-matched bandstop filters can be reconfigured between allpass and bandstop response using PIN diodes as switching elements. The operating center frequency of these filters is at 1 GHz. The discussions of the conceptual perfectly-matched bandstop fil...

A novel compact bandstop filter composed of three cascaded uniplanar double spiral resonant cells (UDSRCs) for high attenuation rates is presented. Through the equivalent circuit prediction and parametric analysis, it is found that the UDSRC exhibits two controllable transmission zeros with great design flexibility through tuning the geometry parameters in a small range. Then, the influence of ...

Abstract: The performance of a wideband bandstop transmission line filter employing a series overlay inductor over two stubs resonating at respectively one half and one quarter of the centre frequency, is described. The structure contributes seven transmission zeros to the stopband and the performance compares to that of a Cauer filter. The structure has the advantage of having impedance levels...

-In this paper, the suspended-membrane-type guided-mode resonance (GMR) filter based on silicon with a narrow bandstop spectrum is experimentally demonstrated. The resonance wavelength of proposed GMR filter is controlled at 1580.6 nm with a bandwidth less than 0.92 nm. The improved spectral performance including the sideband can be extended as far as 415 nm with the maximum transmittance great...

In this paper we present a novel technique for OTA-C filter realizations with finite zeros based on doubly loaded passive ladder networks. Only grounded capacitors are needed; all floating capacitors are replaced with active simulations eliminating bottom-plate parasitic capacitors and non-observable poles. Bandpass, highpass and bandstop filters are easily obtained from a lowpass OTA-C prototy...