Compact microstrip lowpass filter with ultrasharp response using a square-loaded modified T-shaped resonator

Authors

ALI PIRASTEH
SAEED ROSHANI
SOBHAN ROSHANI

DOI

10.3906/elk-1801-127

Abstract

A miniaturized lowpass filter (LPF) with ultrasharp response, good figure of merit (FOM), and simple structure is proposed. The designed structure is fabricated and measured with a 2.9 GHz cut-off frequency. The proposed LPF consists of high impedance lines that are loaded by three similar resonators and two uniform suppressing cells. The filter size is only 0.08~$\times $~0.23~$\lambda $g, which indicates small circuit size. The proposed design exhibits good features, such as an ultrasharp roll-off rate of about 1609 dB/GHz and a good FOM of 162,820. The insertion loss of the proposed LPF is less than 0.14 dB in the passband. With these excellent obtained specifications and flat group delay, this structure can be used in wireless antennae.

Keywords

Microstrip, low-pass filters (LPF), sharp roll-off, resonator

First Page

1736

Last Page

1746

Recommended Citation

PIRASTEH, ALI; ROSHANI, SAEED; and ROSHANI, SOBHAN (2018) "Compact microstrip lowpass filter with ultrasharp response using a square-loaded modified T-shaped resonator," Turkish Journal of Electrical Engineering and Computer Sciences: Vol. 26: No. 4, Article 5. https://doi.org/10.3906/elk-1801-127
Available at: https://journals.tubitak.gov.tr/elektrik/vol26/iss4/5