Adaptive nulling in time-modulated linear arrays with minimum power losses

The synthesis of adaptive time-modulated linear arrays is dealt with by means of an innovative strategy, in which a particle swarm optimiser is used to reconfigure the pulse sequence controlling the static element excitations, as well as the least significant bits of digital phase shifters to maximise the signal-to-interference-plus-noise ratio at the receiver. The reduction of the power content of sideband radiation generated by the periodic on-off commutation of switches is addressed by customising to non-isotropic sources a very effective analytic relationship. A set of selected results is reported and discussed to show the advantages and limitations of the proposed approach. Comparisons with previously published results are also presented.