@mastersthesis{elediasc1248, year = {2013}, school = {University of Trento}, author = {A. Luchita}, title = {Synthesis of sparse time-modulated linear arrays}, abstract = {In the last years, time-modulated arrays have gained a growing interest since they overcome some classical drawbacks of the amplitude-weight control by arbitrarily shaping the radiated pattern by means of the modulation of the static excitations with a set of radiofrequency (RF) switches. Nevertheless, two main problems have limited the consideration of this type of array in the past: the necessity to use reliable RF switches operating at high frequency, and the generation of unwanted harmonics, the so called sideband radiation (SR), which represent a loss in term of radiated power. The new generation of RF switches thanks to the recent advance in nano-technologies are able to satisfy the operative requirements; moreover, the use of global optimization algorithms have shown that the problem of the sideband radiation can be properly handled. This project proposes a PSO-based synthesis technique of sparse time-modulated arrays, in order to reduce the number of elements and minimizing the sideband radiation, applying a joint optimization of pulse durations, pulse shifts and positions of the elements, and exploiting a very effectvive closed-form equation proposed in the literature to evaluate the amount of wasted power in sideband.}, url = {http://www.eledia.org/students-reports/48/} }