A High-Gain Leaky-Wave Endfire Slot Array Based on SISL for 5G Millimeter-Wave Application

This paper proposes a high-gain leaky-wave endfire slot array for 5G millimeter-wave bands integrating the strengths of the air-substrate periodic leaky-wave array and substrate-integrated suspended line (SISL) platform. Firstly, optimize the dimensions and spacing of the slot elements excited by air-substrate parallel strip line to ensure uniform electric field distribution across the radiation aperture, achieving high gain and a high gain-to-length ratio. Additionally, the SISL platform reduces assembly errors through a fabrication method that involves laminating multiple dielectric layers together. This is particularly beneficial compared to traditional air-substrate periodic leaky-wave endfire arrays. Finally, the endfire antenna array exhibits a simulated impedance bandwidth and a 3 dB gain bandwidth of 14.38% and 15.62%, respectively, along with a high simulated endfire gain of 14.12 dBi and a gain-to-length ratio of 6.14. Moreover, the endfire antenna array based on the SISL platform is easy to fabricate. In summary, this proposed array combines the benefits of high gain, high gain-to-length ratio, and ease of fabrication, making it an ideal candidate for arrays in millimeter-wave wireless communication systems.