A miniaturized aperture‐coupled 4 × 4 MIMO array SIW antenna at K band

Abstract

AbstractA planar miniaturized rectangular substrate integrated waveguide (SIW) cavity resonator with an array of patches is presented, which enhances the overall gain of antenna at the K band. The aperture‐coupled feeding is provided from SIW rectangular cavity resonator to reduce radiation losses as in microstrip feeding at a higher frequency. The resonating fields from the cavity excite an array of patches on the substrate. This is further replicated uniformly to design a 4 × 4 element multiple input multiple output (MIMO) antenna. The overall antenna dimension is 2λ × 3.1λ × 0.07λ, where λ is the operating wavelength. The compact structure configuration provides a high peak gain of 13.98 dBi resonating at 19.97 GHz in a broadside direction. An isolation of −17.53 dB is achieved by inserting metal pins. The envelope correlation coefficient of 0.0001 and total active reflection coefficient of −10 dB show characteristics of a high‐performing MIMO antenna. The antenna structure is simulated using HFSS ver. 2022, measured using Anritsu Vector Network Analyzer and Anechoic Chamber, the simulated and measured results are in good concurrence. The antenna is suitable for satellite communication, short‐range wireless applications in IoT, and radar.