摘要 |
Antennas chiefly intended for microwave and millimeter-wave use include geometric-shaped conductive patches on one broad surface of a planar semiconductor substrate. The other broad side of the substrate bears a conductive ground plane. Monolithic PIN diodes are formed by doping the substrate at various points between the conductive patch and the ground plane. Biasing arrangements affect the conduction of the PIN diodes thereby affecting or tuning the optimum operating frequency, the radiation pattern, and/or the impedance of the antenna. In a particularly advantageous configuration, the PIN diodes have lateral dimensions greater than or equal to one-tenth wavelength ( lambda /10) at the operating frequency. Distributed diodes have lower resistance and reactance than discrete or discrete monolithic diodes, thereby providing improved radiating characteristics, and have a relatively large power-handling capability which makes them useful for power transmission.
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