MULTI -LAYERED RING LOG -PERIODIC ANTENNAS ARRAY DESIGN FOR GPS SYSTEMS

The objective of the present study is the design of log periodic ring printed antennas array witch generates circular polarization with wide band by single feed linearly polarized elements for GPS systems. The radiating elements have been fed by magnetic coupling through a slot. The circular polarization is achieved by having a basic 2 ×2 sub-arrays with unique element angular and phase arrangement, both the element angular orientation and feed phase are arranged in the 0°, 90°, 180 and 270° fashion. The purpose of different angular orientations of the patches is to generate two orthogonally polarized fields, while -3dB coupler is used to provide the required amplitude and phase delays for circular polarization generation. This uniquely formed array has the capability of generating excellent circular polarization. An association of the coupler with the antennas has been established. This work is completed using the moment’s method of Momentum software. Good performances of adaptation and polarization were obtained. The simulation results are then presented and discussed.