Mitigating Mutual Coupling in an Antenna Array in the Digital Domain

The impact of mutual coupling on the performance of antenna arrays can be significant as it can alter active impedance and the radiation patterns of embedded elements. This paper introduces an effective method for mitigating mutual coupling in the digital domain using Virtual Load Theory (VLT). Instead of real-time impedance adjustments, VLT utilizes precomputed compensation coefficients derived from the array's impedance (Z) or scattering (S) matrices. These frequency-domain matrices are then applied to the input signal vector, effectively decoupling antenna elements and restoring their Embedded Element Patterns (EEPs) as standalone elements within the array. Simulations of monopole and dipole arrays show that VLT significantly reduces mutual coupling, thereby enhancing the overall system performance.