학술논문
Design of Ka-Band SISL High Selectivity Bandpass Filter With Controllable Zeros
Document Type
Periodical
Source
IEEE Microwave and Wireless Technology Letters IEEE Microw. Wireless Tech. Lett. Microwave and Wireless Technology Letters, IEEE. 33(9):1278-1281 Sep, 2023
Subject
Language
ISSN
2771-957X
2771-9588
2771-9588
Abstract
In this letter, high selectivity bandpass filters (BPFs) using folded stepped-impedance resonators (SIRs) are proposed based on substrate-integrated suspended line (SISL) platform. It is easy to change the position of transmission zeros (TZs) by controlling the strength of electric/magnetic coupling, separately. Also, the structure is compact with double-layer wiring and via holes. To validate the proposed method, two SIR electromagnetic coupling BPFs are implemented on FR-4 substrates. The rectangular coefficients (BW $_{{20\, \text {dB}}}$ /BW $_{3\, \text {dB}}$ ) of the second-order and the fourth-order filters are only 2 and 1.3, respectively. In addition, air cavity, metal shielding wall, and substrate excavation methods also dramatically reduce the loss in substrates.