A novel compact microstrip dual-band bandpass filter (BPF) using embeded SIRs for WLAN/WiMax application

A novel compact microstrip dual-band bandpass filter using embedded SIRs for WLAN/WiMax application is presented in this letter. The filter consists of a main resonator and two embedded resonators. The first passband is generated by main resonator, the second one is created by the embedded resonators. Detail operating principle of the filter is described in this study. Furthermore, the overall circuit size is very compact with only 21 mm×9 mm due to the embedded configuration. A proposed dual-band filter has been fabricated and testing, and the measured results agree well with the simulated ones.