Millimeter-Wave Circularly Polarized Array Antenna Using Substrate-Integrated Gap Waveguide Sequentially Rotating Phase Feed

• Published in: IEEE antennas and wireless propagation letters Vol. 18; no. 6; pp. 1124 - 1128
• Main Authors: Ma, Chaojun, Ma, Zu-Hui, Zhang, Xiupu
• Format: Journal Article
• Language: English
• Published: New York IEEE 01.06.2019; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Antenna array; Antenna arrays; Antenna feeds; Antennas; Bandwidth; Bandwidths; Broadband; Circuit boards; Circular polarization; circularly polarized (CP); Gain; Impedance; Millimeter waves; millimeter-wave (MMW); Patch antennas; Printed circuits; Rotation; substrate integrated gap waveguide (SIGW); Substrates
• ISSN: 1536-1225; 1548-5757
• DOI: 10.1109/LAWP.2019.2910657

A substrate-integrated gap waveguide (SIGW) sequentially rotating phase (SRP)-fed 2 × 2 circularly polarized (CP) patch antenna array is presented for the wideband millimeter-wave application. The antenna element is composed of a truncated square patch, SIGW feedline with three layers of printed circuit board (PCB), and another layer of PCB with an air hole for supporting radiation patch. Each radiation patch is driven by an underneath coupling slot etched on SIGW. A wide axial-ratio (AR) bandwidth is achieved by deploying a 2 × 2 SIGW SRP feed network. Moreover, simple calculation expressions of the characteristic impedance and guide wavelength of SIGW are given for the design of SRP feed network. The fabricated prototype shows an impedance bandwidth of 25.6% covering 22.2-28.8 GHz, 3 dB AR bandwidth of 19% from 22.8 to 27.6 GHz, and peak gain of 11.53 dBic.