Miniaturized Design of Microstrip-Fed Slot Antennas Loaded With C-Shaped Rings

A novel miniaturized design of a microstrip-fed slot antenna is presented. By properly loading a pair of C-shaped rings inside a half-wavelength slot, the fundamental resonant frequency can be significantly decreased. This letter illustrates the mechanism of miniaturization and key dimension parameter analysis. An optimized design with 50% size reduction was fabricated and measured, where very good agreement between simulation and measurement was obtained. The results show that the presented miniature slot antenna maintains the nominal radiation patterns of slot antennas with some moderate gain degradations.