In this paper, nonrecursive digital filter design using the exponential window is investigated [1,2]. The exponential window proposed by the author [3] has computational cost advantage compared to the well-known Kaiser window due to having no power series expansion in its time domain representation. First, the filter design equations for the exponential window to meet the given low pass filter ...

Periodic structures are well known in various branches of physics for their ability to provide a stopband. In this article, using optical periodic structures we showed that, when a second periodicity--very closed to the original periodicity is introduced, large number of states appears in the stopband corresponding to the first periodicity. In the limit where the two periods matches, we have a ...

This paper proposes asymmetrical step-impedance resonators bandpass filters (ASIRs) for suppressing a wide stopband, ensuing in size reduction and ease of fabrication. The filters have been designed at the operating frequency around 2.0 GHz using halfand quarter-wavelength asymmetrical step-impedance resonators. The concept of existent oddand even-mode characteristics is used to approve the pro...

Employing a family of dimpled and slotted spherical resonators, set X-band waveguide bandpass filters (BPFs) is presented in this study. The resonators originated from with depression (hence, dimples are formed) cutting slots into the resonator shell. With large number experiments, combination using twisted coupling topology, slotting on results simultaneous low insertion loss (IL), good out-of...

Up to now we have discussed various approaches to discrete-time filter design that are all based on approximating the response of ideal lowpass, highpass, or bandpass filters, etc., with the designs involving various deterministic satisfaction of constraints such as passband and stopband ripple, and passband and stopband edge frequencies. In many actual situations we seek to design a filter tha...

In this paper, an inverse S-shaped slotted ground structure (S-SGS) is proposed and analyzed. The S-SGS generates dual attenuation poles that can be easily controlled by its structure parameters. The equivalent circuit of the S-SGS consists of lumped elements that can be extracted from the measured S parameters. Moreover, several S-SGS cells are applied to form a miniaturized lowpass filter (LP...

A novel compact bandpass filter (BPF) with wide upperstopband has been proposed in this paper. The structure is based on spiral-shaped resonators. Cross coupling is used to generate two transmission zeros at the lower and upper stopbands. Therefore, the out-of-band performance is improved. In addition, two spur-lines are adopted in the feed lines to reject the spurious response. The central fre...