ABSTRACT In this letter, a novel pattern and polarization reconfigurable circular patch antenna is presented. The antenna is fabricated on a substrate of dielectric constant 4.4 and thickness 1.5 mm, and a circular radiation patch and eight symmetrical parasitic patches are loaded above the substrate. All parasitic patches are connected to the circular patch through eight p‐i‐n diodes, whose ON/OFF states are controlled by four direct current (DC) biases. By applying different voltages to the DC biases, the TM 41 or TM 11 modes of circular patch can be excited, and the antenna can realize reconfiguration between three states: unidirectional mode with x ‐axis linear polarization, unidirectional mode with y ‐axis linear polarization and omnidirectional mode with z ‐axis linear polarization. The measured results show that the proposed antenna could be operated in the 2.4‐GHz ISM band. Besides, stable performance of the antenna is obtained when setting on the human body. The proposed antenna has excellent reconfigurability and can be applied in the fields of wireless communication and wearable devices.
Gao et al. (Mon,) studied this question.