In MIMO technology, which employs multiple antennas to boost data rates, reliability, and efficiency, the proximity of antenna elements often presents challenges from mutual coupling and low isolation. Attaining high isolation between adjacent ports in MIMO antennas is crucial for enhancing the overall performance of modern wireless communication systems. This paper discusses various methods to mitigate mutual coupling and improve isolation while maintaining compact antenna designs. Methods like network decoupling, metamaterials, neutralization lines, parasitic elements, and DGS are analyzed. The effectiveness of each method in reducing surface wave propagation and coupling is evaluated, emphasizing their role in optimizing MIMO antenna performance. These methods achieve isolation exceeding 15 dB and return loss below −10 dB, ensuring effective impedance matching. They also enhance transmission coefficients, enabling efficient power transfer with minimal interference.