Diverse SRRs Loaded Millimeter-Wav SIW Antipodal Linearly Tapered Slot Filtenna with Improved Stopband

An antipodal linearly tapered slot filtenna (ALTSFA) with diverse split-ring resonators (SRRs) is proposed. The ALTSFA is actually an antipodal linearly tapered slot antenna (ALTSA) fed by a substrate integrated waveguide (SIW) whose cutoff characteristic is utilized to obtain a lower band suppression. A broad-coupled complementary SRR (BC-CSRR) and 11 SRRs on the ALTSA are used to achieve an upperband suppression. Hence, filtering function with wide stopbands is achieved without enlarging its size and deteriorating the radiation performance. A prototype of the proposed ALTSFA was fabricated and measured, and a bandwidth ranging from 23.5 to 27.5 GHz, a maximum gain of 10 dBi, and a maximum out-of-band suppression of 20.55 dB are observed, validating its good performance. The proposed ALTSFA can be a promising candidate for compact fifth-generation mobile communications and beyond (5G/B5G) millimeter-wave communication system.