Various examples are provided for meander line (ML) slots, which can be used for mutual coupling reduction. In one example, an antenna array includes first and second patch antenna elements disposed on a first side of a substrate, the first and second patch antenna elements separated by a gap. The antenna array can include a meander line (ML) slot formed in a ground plane disposed on a second side of the substrate. A plurality of ML slots can be aligned with the gap between the first and second patch antenna elements. In another example, a method includes forming first and second antenna elements on a first side of a substrate and forming a ML slot in a ground plane disposed on a second side of the substrate aligned with a gap between the first and second antenna elements.