摘要 |
A tunable artificial dielectric material achieves the weight reductions made possible in U.S. Pat. No. 6,075,485 and further achieves even higher resonant frequency tuning ratios. In one embodiment of the invention, the artificial dielectric substrate for a patch antenna comprises alternating low and high permittivity layers, with the high permittivity layers each comprised of printed capacitive Frequency Selective Surface (FSS). An example FSS of the invention has a voltage tunable effective sheet capacitance by virtue of varactor diodes integrated into each unit cell. By appropriate adjustment of the bias voltage across the varactor diodes, the amount of the electric field stored in the substrate can be varied, which further varies the resonant frequency of the patch antenna.
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