A reconfigurable Bessel antenna for near‐field beam deflection.

This letter presents a reconfigurable leaky‐wave antenna for near‐field beam manipulation. The proposed antenna is based on a radial waveguide and a reconfigurable capacitive sheet, which is divided into four regions. To realize the reconfigurability, PIN diodes are electrically soldered to the gap between the adjacent patches in the upper surface except for the isolation zone, where no diodes are printed. By switching the states of PIN diodes in each region by turns, wavenumbers with two different azimuths are generated, thus the near‐field beam deflection can be achieved in different regions. By using the Genetic Algorithm, the PIN diodes are optimally deployed for realizing high antenna efficiency. The simulated (measured) results show that with the implementation of the reconfigurable capacitive sheet results in a near‐field beam scanning property. The beam deflection at a tilted angle of 17.4° (16.2°) can be achieved in different regions. [ABSTRACT FROM AUTHOR]