Design and performance optimisation of microstrip antennas

Microstrip antennas are frequently used in mobile communication systems, radar, space, satellite and navigation systems in recent years increasingly. Rectengular, H, E, round etc differen shaped antennas are used according to circumstances that their applicaion scopes requiring. In order to obtain required performance where they are used, many different applications are carried out by changing antenna geometry, substrate type, feeding technics. Rectangular, E, H and including different shaped of cavities antenna studies are researched, H shaped and including rectangular cavities antennas are designed and simulated within scope of the thesis. Negative influences of rectangular caved antenns on fr and BW became and input and motivation of investigating new geometric model having positive influence on fr and BW. After many design and simulation, positive influence of circular caved antennas on fr and BW is obviously observed. An equation model valid between 1,5-2,5 GHz and having r and h as inputs and fr as output has been obtained by curve fitting via many simulations of circular caved structure on different frequencies. A design proposal that could be used during automotive navigation antennas has been obtained also after results around 1,57 GHz. Furthermore, some fruitful clues to support cases where theorical equations not totally helpfull are obtained from simulation results.