STUDY OF IMPEDANCE AND RADIATION PROPERTIES OF A CONCENTRIC MICROSTRIP TRIANGULAR-RING ANTENNA AND ITS MODELING TECHNIQUES USING FDTD METHOD

A concentric microstrip triangular-ring antenna structure using the lo g-periodic principle for increasing the impedance bandwidth of the mic rostrip patch antenna is described, The finite-difference time-domain (FDTD) method is applied to analyze the proposed structure. A special technique to model the slanted metallic boundaries of the triangular r ing has been used in the general FDTD algorithm to avoid the staircase approximation. The method improves the accuracy of the original FDTD algorithm without increasing the complexity, The radiation patterns at different frequencies over wide-band width are obtained experimentall y.