Ultra-wideband bandpass filter with multiple notched band

A novel ultra-wideband (UWB) bandpass filter that is capable of integrating multiple notch bands is proposed in this paper. The external resonators are integrated to obtain multiple notch bands. UWB filters of this type with single-, double-, and triple notched bands are designed not only to meet the Federal Communications Commission (FCC)-defined UWB indoor limit but to cancel the interferences from the wireless local area network (WLAN) signals (i.e., 5.2GHz and 5.8GHz bands) and 6.8GHz RF identification (RFID) communication. The proposed filter has good performance and is attractive for UWB communication and radar systems.