Size Reduction of a Low-Profile Frequency-Reconfigurable Filtering Patch Antenna

A low-profile frequency-reconfigurable filtering patch antenna is optimized for size reduction in this paper. The original design achieves the filtering functionality by using four parasitic strips and two lateral stubs. These added components introduce reverse currents to provide the filtering for the upper and lower bands, respectively. Frequency-reconfigurability is achieved by integrating groups of varactor diodes as tuning elements on the main patch, parasitic strips and lateral stubs. In this paper, grounded-shorted parasitic strips are applied to reduce the antenna size while maintaining similar filtering functionality and frequency tuning range. Simulated results indicate that the proposed approach can reduce the antenna length by 21%.