Design of wide stopband lowpass filter with sharp roll-off

Compact Microstrip Lowpass Filter with Sharp Roll-off and Wide Stopband Using Semicircle Ended Stub Resonator

In this paper, a semicircle ended stub resonator, cascaded to a modified radial patch to design a compact lowpass filter with sharp roll-off and wide stopband is proposed. This filter has 3 dB cutoff frequency at 1.54 GHz. The transition band is only 0.26GHz from 1.54 GHz to 1.8 GHz with corresponding attenuation levels of −3 dB and −20 dB respectively. Maximum insertion loss is 0.1 dB in the p...

Wide Stopband and Sharp Roll-off Microstrip Lowpass Filter using Modified Rhombic Shaped Resonator

Compact LPF using T-shaped resonator with sharp roll-off and ultra wide stopband

  In this paper, a microstrip lowpass filter with an ultra-wide stopband with sharp roll-off and compact size is designed and fabricated. To provide a very small dimension, T-shaped and stepped impedance have been used. The cut of frequency at -3 dB is 3.1 GHz. In the proposed structure, insertion loss is less than 0.12 and return loss is more than 15 dB. To achieve a -20dB attenuation level...

Compact Microstrip Lowpass Filter with Wide Stopband and High Attenuation

A compact microstrip lowpass filter using radial stub resonators is developed. This filter is composed of two radial stub resonators that are asymmetrically connected to each other by a stepped impedance structure. This structure results in a very high rejection and wide stopband. The proposed filter with a 3 dB cutoff frequency of 2.07 GHz has been designed, fabricated and measured. Measuremen...

Highly Selective Lowpass Filter with Wide Stopband in Suspended Stripline Technology for Millimeter-wave Diplexer Applications

This paper presents a low loss and high selective lowpass filter which is implemented using suspended stripline (SSL) technology. The proposed structure is comprised of a 13th order generalized Chebyshev lowpass filter which enjoys integrated waveguide-to-SSL transitions. This filter is designed and fabricated to be used as lowpass channel of a U-band diplexer employed in frontend of a U-band d...