FPGA-Controlled Switch-Reconfigured Antenna

In this letter, p-i-n diodes are used as switches to connect and disconnect four patch sections to a midsection of a planar antenna. The antenna system is connected to the field programmable gate array (FPGA) board controlling the activation of these switches. The antenna with the incorporated diodes is designed, installed, and measured. The methodology for using an FPGA to optimally control and produce the desired antenna frequency operation is presented and analyzed. The analogy between the measured and simulated results is found to be satisfactory. The proposed control methodology can be used with various antenna designs to obtain different possible states in an easy, fast, and low-cost manner.