The new role of time-modulation for innovative array synthesis

The synthesis of multiple beam patterns at the harmonic frequencies generated by a time-modulated linear array is addressed in this work. The pulse sequence modulating the static element excitations is defined to obtain the desired patterns in the first harmonic radiations. Towards this aim, the degrees of freedom available in the time-domain of a time-modulated array are optimized by means of an algorithm based on the particle swarm optimizer. A set of results regarding the synthesis of sum and difference patterns is reported and discussed to assess the effectiveness of the proposed method.