This paper is aimed at investigating a method to design non-uniform MIMO arrays using an analytical strategy based on Almost Difference Sets (ADSs). Numerical experiments are carried out to compare the properties of the ADS-based layouts with traditional uniform arrangements in terms of achievable capacity and design efficiency. Representative results from a preliminary numerical analysis indicate that the proposed approach enables a significant capacity increase in all considered scattering scenarios. More specifically, larger improvements are yielded in case of poor-scattering environments where the per- formances of M IM O systems usually worsen.