Compact Wide-band Overlapped Patches Microstrip Antenna

In this paper the bandwidth of a single layer microstrip patch antenna is enhanced by using multi-resonance technique without significantly enlarging the size of the proposed antenna. In this work the validity of the design concept is demonstrated by two examples with 51.4% and 56.8% bandwidths. In the first example multiple resonances are achieved by overlapping three square patches of different dimensions along their diagonals to form a non-regular single patch but in the second example a slot is incorporated into this patch to expand its bandwidth. A finite difference time domain (FDTD) method full wave simulator FIDELITY is used to simulate these antennas. The obtained results have been compared to other results produced using IE3D-a commercial simulator based on the method of moment and good agreements have been found. These two antennas provide stable far field radiation characteristics in the entire operating band with relatively high gain