Planar antennas are used in several technical applications. The family of planar antennas contains microstrip antennas, which are very popular due to the low weight, low profile, simple manufacturing and easy mass production. Lower gain and excitation of surface waves are disadvantages of microstrip antennas. The propagation of surface waves can be efficiently suppressed if the conventional substrate is replaced by an electromagnetic bandgap (EBG) substrate. Microstrip antennas on EBG substrates have been presented in an open literature for several years. Nevertheless, no published work is devoted to the design of EBG substrates, which can suppress surface waves at several frequencies those cannot be covered by a single bandgap. In order to reach optimum parameters of designed antennas, selected global optimization methods are applied (genetic algorithms, particle swarm optimization, ant colony optimization).

This thesis is focused on the design of the antenna to a specific application XY. Emphasis is placed on a narrow antenna beam width, which will ensure full-fledged profit for the tag directly below the antenna. This thesis presents a total of five proposals that could be used by XY application. This thesis also presents the results of field measurements, which confirm the improved characteristics of the antenna with parasitic patch.