Multiple Mode Resonator Based Triple Band Filter for WLAN, Intelligent Transportation System, Satellite Communication and X-Band Applications

Abstract

A compact triple band filter is proposed in this paper. Low insertion loss and triple band characteristics are achieved by two stubs connected up and down to the multi mode resonator (MMR). The proposed triple-band filter offers five transmission zeroes (TZs) at 4.25 GHz, 6.78 GHz, 9.06 GHz, 10.75 GHz and 12.85 GHz to allow for independent control of each frequency band and avoid the interference between bands at resonant frequency of 5.3 GHz, 7.8 GHz and 10.3 GHz. Proposed filter achieved three bands from 5.22 GHz to 6.13 GHz, 7.63 to 8.41 GHz and 10.29 GHz to 10.42 GHz. First band is used for wireless local area network (WLAN) and Intelligent Transportation System (ITS), second frequency band is used for satellite communication and third frequency band is used for X- band applications respectively. The filter is realized on an Arlon 25N substrate ($\\varepsilon_{r}$ = 3.38 and thickness = 1.524 mm).