In this paper, a new method is presented for the design of a low pass filter (LPF) based on an LC equivalent circuit. Firstly, new formulas are proposed to calculate an LC equivalent circuit of a rhombus-shaped resonator. Secondly, the transfer function and transmission zero of the rhombus-shaped resonator are extracted, based on the presented formulas. Then other rhombus-shaped resonators are designed, based on the extracted formulas. The proposed filter has a cut-off frequency with an attenuation level of 3 dB at 1.54 GHz. The obtained return loss and insertion loss in the pass band are 16 dB and 0.1 dB, respectively. The designed filter is fabricated on RT-5880 with 31 mil thickness.
Compact size, LC equivalent circuit, low pass filter, microstrip, rhombus-shaped resonator, wideband
Hookari, Mohsen; ROSHANI, SAEED; and ROSHANI, SOBHAN
"Design of a low pass filter using rhombus-shaped resonators with an analyticalLC equivalent circuit,"
Turkish Journal of Electrical Engineering and Computer Sciences: Vol. 28:
2, Article 19.
Available at: https://journals.tubitak.gov.tr/elektrik/vol28/iss2/19