deepened. In the second chapter a preliminary study on surface current distribution over a

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I NTRODUCTION

The aim of this thesis work is the design of a new reconfigurable microstrip antenna for Cognitive Radio (CR) applications. Today the Software Defined Radio (SDR) concepts are more and more widespread due to ongoing addition of new standards and the necessary of more flexible wireless networks. In this scenario, a key role is played by technologies that exploits the SDR platform, known as CR. Differently from common receiver, CR platforms use components with peculiar features. In particular the antenna employed in a CR receiver should be: reconfigurable, tunable, low profile, light and with a low power consumption. The microstrip antenna described in this document tries to satisfy the above mentioned specifications. In the first chapter an overview about SDR and CR is presented.

In the last part of section the state of art about the antenna designs for CR applications is

deepened. In the second chapter a preliminary study on surface current distribution over a

simple patch antenna is developed and the results of comparison between cavity model and

full wave analysis are shown. In the later chapter the antenna design i.e., the object of the

study, is explained in detailed form. Then the presentation of simulation results about a

preliminary study of microstrip antenna, composed by some patch and RF switches that

requires an impedance matching network (whose design is presented as well), is shown: in

particular, a parametric study about the dimensions of basic structure is reported. This

study is aimed at an increase of the reconfigurable property and the relative bandwidth at

the resonant frequencies. In the conclusions the final structure and its simulation results are

highlighted.