Design of a miniaturized high-isolation dual-frequency antenna based on quarter-mode substrate integrated waveguide

A dual-band antenna based on the quarter-mode substrate integrated waveguide (QMSIW) operating at 5.2GHz and 5.8GHz is designed and implemented. The QMSIW structure reduces the volume of the antenna while maintaining the characteristics of low loss and low profile of the substrate integrated waveguide (SIW). By adding two rows of metallized through holes to the QMSIW and etching two rectangular slots and asymmetric Y-shaped slots, the size is reduced and high isolation is achieved. After testing, the antenna gains at 5.2 GHz and 5.8 GHz are 6.0 and 6.1 dBi, respectively, with cross-polarization ratios greater than 25 dB and 20 dB, respectively. The proposed antenna achieves good miniaturization and high isolation (greater than 34 dB), with dimensions of 0.42λ₀×0.42λ₀× 0.01λ₀. The test results agree well with the simulation results.