Surrogate-Assisted Defected Ground Structure Design for Reducing Mutual Coupling in 2 × 2 Microstrip Antenna Array

A surrogate-assisted defected ground structure (DGS) design is proposed to suppress
E-
and
H-
plane couplings simultaneously in a 2 × 2 microstrip antenna array at 2.45 GHz. The DGS is designed and analyzed based on the magnetic current and mode theory. Machine learning is employed to sweep the DGS parameters within defined limits and fine-tune them to obtain optimal design, predominantly shortening the DGS design time. A 2 × 2 microstrip antennas array is used as a test case to corroborate the efficacy of the proposed scheme. Simulation and measurement results show that the proposed DGS can significantly reduce
E-
and
H-
plane couplings.