volume | PIER Journals

Abstract

This paper presents a high-gain substrate-integrated waveguide antenna featuring a narrowly-focused radiation beam with enhanced cross-polarization characteristics, specially designed for precision millimeter-wave radar systems and n-257 band point-to-point 5G wireless applications. The antenna incorporates a novel design with dual radiator slots arranged both vertically and horizontally on the broadside wall of the substrate-integrated waveguide, forming a Non-Intersecting Asymmetrical T-shaped unit cell. This unit cell is periodically distributed to create an eight-element radiator array, thereby improving the antenna's gain and bandwidth. The antenna operates in the frequency range from 27 GHz to 28.54 GHz, thereby covering the n-257 5G frequency band. Moreover, it exhibits a half-power beamwidth of 8.1°, low side-lobe level of -13.3 dB, and cross-polarization discrimination level of 25 dB, making it suitable for high-precision millimeter-wave radar sensing applications. The proposed design provides a peak gain of 10.51 dBi with a radiation efficiency of 84.82%. Moreover, the integration of a dome-shaped polytetrafluoroethylene dielectric lens achieves a peak gain of 12.50 dBi with an enhanced radiation efficiency of 86.35%. The antenna design and simulation were performed using CST Studio Suite, followed by an experimental validation. Owing to its high gain, low side-lobe levels, and a sharply focused main-lobe beam with excellent cross-polarization discrimination, the antenna is well-suited for millimeter-wave radar sensing and point-to-point 5G communication systems.

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Mr. Umasankar Prasad Ananthasankar

Dr. Thulaseedharan Rekha

Dr. Anju Puthiyadam Mathews