Compact Wideband Patch Filtenna with Enhanced Out-of-Band Suppression

• Published in: IEEE antennas and wireless propagation letters 2023-09, Vol.22 (9), p.1-5
• Main Authors: Da Liu, Quan, Dong, Qing, Wen, Jun Xiang, Ye, Liang Hua, Wu, Duo-Long, Zhang, Xiu Yin
• Format: Article
• Language: English
• Subjects: Antennas; Bandwidths; Broadband; Broadband filtenna; Gain; Impedance; Mobile communication systems; out-of-band suppression; Passband; patch antenna; Probes; Resonant frequency; Slot antennas; Substrates; Universal Mobile Telecommunications System (UMTS)
• ISSN: 1536-1225; 1548-5757
• DOI: 10.1109/LAWP.2023.3287350

A compact broadband patch filtenna with enhanced stopband suppression is presented in this letter. The designed antenna is configurated with a simple structure having two substrates of 0.04 λ0 spacing (λ0 is the free space wavelength at the center frequency). A rectangular patch with Π-, Γ- and inverted Γ-shaped slots is printed on the top substrate and fed by a coaxial probe. The above three slots create additional resonance modes to broaden the impedance bandwidth and generate two out-of-band radiation nulls to enhance the stopband suppressed level. An antenna prototype with a dimension of 0.56 λ0 × 0.56 λ0 × 0.06 λ0 is fabricated to demonstrate its characteristic. A stable gain of 7.2 ± 0.4 dB over the wide impedance bandwidth of 17% (1.88 - 2.23 GHz) is achieved, and the out-of-band suppression level is beyond 20.6 dB. These features make the filtenna a promising candidate for the PCS 1900/UMTS 2000 bands in mobile communication systems.