The synthesis of time-modulated arrays (TMAs is carried out by means of a customized implementation of the Particle Swarm optimization (PSO), carefully taking into account in the analysis block the non-linear characteristics of the radio-frequency (RF) switches used in antenna beam-forming network and the mutual coupling effects between the array elements. A set of numerical results are reported and discussed in a comparative fashion with those obtained with a state-of-the-art method limited to deal with ideal TMAs.