A tunable bandpass filter with constant absolute bandwidth using folded slotline uniform‐impedance resonators.
- Resource Type
- Article
- Authors
- Guan, Xuehui; Xu, Mengrou; Ren, Baoping
- Source
- International Journal of RF & Microwave Computer-Aided Engineering. May2022, Vol. 32 Issue 5, p1-7. 7p.
- Subject
- *BANDPASS filters
*RESONATORS
*BANDWIDTHS
*VARACTORS
*TRANSMISSION zeros
- Language
- ISSN
- 1096-4290
A simple tunable bandpass filter (BPF) with constant 3‐dB absolute bandwidth using folded slotline uniform impedance resonators (UIRs) is proposed. The tunable BPF consists of a pair of coupled folded slotline UIR, where the varactor diode elements are loaded to control its center frequency. Measured results show that a wide tuning range from 1.76 to 2.35 GHz with constant 3‐dB absolute bandwidth (ABW) of 310 ± 10 MHz is realized. Meanwhile, a pair of transmission zeros (TZs) are generated aside both sides of the passband due to the coupling between source and load, which improves the selectivity of the passband. [ABSTRACT FROM AUTHOR]