A New Compact Filter-Antenna for Modern Wireless Communication Systems

• Published in: IEEE antennas and wireless propagation letters Vol. 10; pp. 1131 - 1134
• Main Authors: Wei-Jun Wu, Ying-Zeng Yin, Shao-Li Zuo, Zhi-Ya Zhang, Jiao-Jiao Xie
• Format: Journal Article
• Language: English
• Published: IEEE 2011
• Subjects: Antennas; Band pass filters; Filter-antenna; Filtering theory; Gamma -shaped antenna; Microstrip filters; Microwave filters; open-loop resonator filter; Q factor; Resonator filters; synthesis
• ISSN: 1536-1225; 1548-5757
• DOI: 10.1109/LAWP.2011.2171469

Design, fabrication, and measurement of a new compact filter-antenna for modern wireless communication systems are presented in this letter. Two microstrip square open-loop resonators, a coupled line, and a Γ-shaped antenna are used and integrated to be a filter-antenna. The Γ-shaped antenna is excited by a coupled line that is treated as the admittance inverter in filter design. The Γ-shaped antenna performs not only a radiator, but also the last resonator of the bandpass filter. Therefore, near-zero transition loss is achieved between the filter and the antenna. The design procedure follows the circuit approach-synthesis of bandpass filters. Measured results show that the filter-antenna achieves an impedance bandwidth of 16.3% (over 2.26-2.66 GHz) at a reflection coefficient | S 11 | <; - 10 dB and has a gain of 2.41 dBi.