A Mechanically Reconfigurable Patch Antenna With Polarization Diversity

A mechanically reconfigurable patch antenna with polarization diversity is presented. The antenna is composed of a fixed L-probe feed on a bottom substrate layer and a patch with truncated corners on an upper substrate layer that can rotate in azimuth. The layers are held together with a thin bolt going through the center of both layers. The handedness of the circular polarization (right-hand circular polarization or left-hand circular polarization) may be changed by simply rotating the upper substrate by 90° with respect to the fixed capacitively coupled feed. Additionally, since the upper layer is not permanently attached, the resonant frequency may be modified by swapping out the patch with one having different dimensions. The L-probe presented in this letter is impedance-matched to patch sizes resonating in the range of 1.0-1.8 GHz. The antenna design is presented along with measurement results, which are shown to be in excellent agreement with simulations. This simple and low-cost reconfigurable design is ideal for applications or systems where the antenna requirements may be variable.