Stacked microstrip antenna with wide band and high gain

A microstrip antenna composed of radiating, matching, and director elements is presented. The director element increases the gain of the antenna, while the matching element widens the frequency bandwidth of the input impedance. By adjusting the distance between the matching element and the radiating element by varying the height of the former element, the input impedance of the antenna is matched to the output impedance of the feed line. The proposed antenna, therefore, has wider impedance bandwidth and higher gain than the single-patch antenna. Since this antenna can be directly fed from the back of the ground plane, the feed circuit is simpler than that of the planar array antenna. For mobile communications, the stacked microstrip antenna array is useful when a gain of about 8 approximately 12 dBi is required.<
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