A 45[Formula Omitted] Linearly Polarized Hollow-Waveguide 16[Formula Omitted]16-Slot Array Antenna Covering 71-86 GHz Band

• Published in: IEEE transactions on antennas and propagation Vol. 62; no. 10; pp. 5061 - 5067
• Main Authors: Tomura, Takashi, Hirokawa, Jiro, Hirano, Takuichi, Ando, Makoto
• Format: Journal Article
• Language: English
• Published: New York The Institute of Electrical and Electronics Engineers, Inc. (IEEE) 01.10.2014
• Subjects: Antenna arrays; Antennas; Arrays; Broadband; Cross polarization; Genetic algorithms; Reflection; Sidelobes
• ISSN: 0018-926X; 1558-2221
• DOI: 10.1109/TAP.2014.2345567

A 45[Formula Omitted] linearly polarized hollow-waveguide 16 [Formula Omitted] 16- slot array antenna is proposed for point-to-point wireless communication in the 71-76 GHz and 81-86 GHz bands. The antenna is composed of an equally-split corporate-feed circuit and 2[Formula Omitted]2-element sub-arrays which radiate the 45[Formula Omitted] linear polarization. Low sidelobe characteristics are obtained in the E-plane by diagonal placement of the square antenna rotating by 45 degrees. To suppress cross polarization, a radiating narrow-slot pair is adopted. The sub-array is designed by a genetic algorithm and 25.7% reflection bandwidth for [Formula Omitted] is obtained by decreasing the [Formula Omitted] of two eigenmodes of the radiating element. A 16[Formula Omitted]16-element array is fabricated by diffusion bonding of thin copper plates. The total thickness is 3.2 mm which is less than 1 free space wavelength. A high gain of 32.9 dBi, high antenna efficiency of 86.6% and low sidelobe characteristics of [Formula Omitted]-dB first sidelobe levels are measured at the center frequency of 78.5 GHz. Further, the broadband characteristics of reflection [Formula Omitted], show a gain of more than 31.4 dBi, and low cross polarization of less than [Formula Omitted] dB are achieved over the 71-86 GHz band.