Compact dual-band loop-loaded monopole with integrated band-select filter for WLAN application

A compact loop-loaded dual-band monopole with integrated band-select filter for 2.45/5.2-GHz wireless local area network (WLAN) is presented. The proposed integrated antenna system comprises a loop-loaded dual-band monopole radiator and a microstrip dual-band pseudo-interdigital bandpass filter. Instead of using the traditional 50Ω interfaces, the impedance between the filter and antenna is optimized to improve the performance. The proposed integrated antenna system provides good selectivity and rejection in out of band regions and omnidirectional radiation patterns within the two desired bands. The measured results show good agreement with the simulated ones.