A Novel UWB Filter with WLAN and RFID Stop-Band Rejection Characteristic using Tri-Stage Radial Loaded Stub Resonators

摘要

The paper presents a novel approach for designing compact ultra-wideband (UWB) band-pass filter with WLAN and RFID stop-band rejection characteristic which is obtained by using tri-stage radial loaded stub resonators. The main advantage of the proposed filter is that the Stop-band can perfectly reject the WLAN and RFID (5.2GHz-6.1GHz) signals. The density and the equivalent model of one filter for testing the presented design is given depending on the odd/even excitation resonance condition. The characteristics of the filter are analyzed and discussed. To verify the proposed methods, two filters are designed and fabricated. Measured results show the proposed UWB properties from 3 GHz to 10.8 GHz and stop-band properties from 5.2 GHz to 6.1 GHz. The designed filters can be integrated in UWB radio systems and can efficiently enhance the interference immunity from undesired signals such as wireless local area network (WLAN) and RFID.