A miniaturization band-pass filter with ultra-narrow multi-notch-band characteristic for ultra-wideband communication applications

In this paper, we present a novel approach for designing compact Ultra-Wideband (UWB) band-pass filters with desired multi-notchband characteristics. The multi-notch-band features are realized by using a ring-stub multimode resonator, while the equivalent model is also obtained by using the odd/even excitation resonance condition. The fabricated prototype of the band-pass multi-notch-band filter demonstrates a good behavior as expected. Simulated and experimental results show that the proposed filter with a compact size of 25×10 mm2, has an impedance bandwidth between 3.0 GHz and 10.6 GHz; while the multiple notch bands are achieved and their center frequencies are located at 3.9 GHz, 5.25 GHz, 5.9 GHz, 6.8 GHz and 8.0 GHz. The proposed filter is suitable for being integrated in UWB radio systems to efficiently enhance the interference immunity from unexpected signals, such as Worldwide Interoperability for Microwave Access (WiMAX), Wireless Local-Area Network (WLAN), 6.8 GHz Radio Rrequency Identification (RFID) communication and X-band satellite communications. © 2014 ACES.