volume | PIER Journals

Abstract

This paper presents the design and optimization of a wideband filtering antenna (filtenna) for UWB applications. The design combines a wideband antenna and a feed-line-mounted band-stop filter (BSF) to suppress Wi-Fi (5-6 GHz) interference while keeping the design compact and simple. This antenna is built on a 32 × 32 mm² FR4 substrate with a partial ground plane and is embedded with a circular ring resonator in the feed line to obtain the desired rejection characteristics. The antenna was designed and simulated using CST Studio Suite. The outcome revealed that the designed filtenna has a wide operating range of 2.78-11.79 GHz with a targeted rejection band around 5-6 GHz. deep resonances are observed at 3.35 GHz and 7.40 GHz, with reflection coefficient of -23.85 dB and -55.14 dB, respectively indicating good impedance matching outside the rejected band. The filtenna was fabricated and experimentally characterized in terms of S₁₁, showing the intended band-rejection behavior with some differences between the simulated and measured response. A parametric study of the ring dimensions shows how the position and bandwidth of the rejection band can be tuned while the UWB response outside the notch is preserved. The filtenna was fabricated, and its measured S₁₁ confirms the band-rejection behavior, with some differences from the simulated response. The results show that a compact feed-line ring resonator is a simple way to introduce WLAN rejection into a UWB antenna, making the design a candidate for sub-6 GHz and IoT applications.

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Dr. Esraa M. Majeed

Dr. Ahmed M. A. Sabaawi