![Sample our Physical Sciences journals, sign in here to start your FREE access for 14 days]({"type":"image" , "src" : "/sda/110819/TOC-Subject-Sample-2021-Physical-Sciences.jpg"})
Abstract
A switchable bandpass filter using E-type resonators with two-state frequency responses is presented in this paper. The E-type resonator is a short-circuited stub loaded on hairpin resonator, and two passband frequencies of which can be regulated by hairpin resonator and the stub. By using pin diodes on/off characteristics, the proposed filter can work as a dual-band bandpass filter, center at 2.45/5.2 GHz, and a single band bandpass filter, center at 5.2 GHz, respectively, which could be appropriately used for WLAN application. An experiment was carried out to demonstrate the performance of the proposed filter, and it was shown that the measured and simulated performances are in good agreement. The BPF achieved insertion loss of less than 2.5 dB and return loss of greater than 15 dB.