A two-input two-output (TITO) current-mode universal biquad using only four dual-output operational transconductance amplifier (DO-OTAs) and two grounded capacitors is described. By appropriately connecting the input and output terminals, the proposed circuit can provide lowpass, bandpass, highpass, bandstop and allpass current responses. The filter also offers an independent electronic control...

A novel bandpass filter (BPF) based on half-wave-length (λ/2) stepped-impedance resonators (SIRs) is proposed in this paper. By properly designing the impedance ratios of the SIRs, the spurious harmonics of the filter can be pushed to upper frequency. With several bandstop structures such as open stubs and defected ground structures (DGSs) applied to the BPF, a good stopband performance is obta...

In this work it is shown that one of the most employed filtering systems for use in continuous-flow industrial microwave ovens, namely doubly corrugated filters, does not work properly for many values of the electric permittivity of the processed material when it is partially filled. Thus, a novel bandstop filter which solves these inconveniences, based on a combination of metallic irises and d...

The method of least squares (MLS) is used to develop an algorithm for the optimum design of any type of filter under any design specifications for the realization of lowpass, bandpass, highpass and bandstop characteristics. The proposed filter design method can be used for any general filter network topology, which provides high flexibility for the selection of circuit configurations suitable f...

Abstract—A novel miniaturized dual-band bandstop filter (DBBSF) is proposed by using the T-shaped defected microstrip structures (DMSs) and the U-shaped defected ground structures (DGSs) in this paper. The layout of the dual-band bandstop resonator (DBBSR) is presented at first. The dual stopbands of the DBBSR can be separately controlled since the mutual coupling of the defected structures is ...