A slotted square patch antenna for dual-band circularly polarization operations

A dual-band circularly polarization (CP) antenna using a slotted square patch with single probe feeding is presented. CP can be implemented by cutting symmetrically two corners from a square patch, and dual-frequency is obtained by slotting another corner-cut patch inside the original one. The potential application is the Bei-Dou terminal operating at 1618.25 MHz and 2491.75 GHz.