3D Beamsteering Low Complexity Reconfigurable Multilevel Antenna

A low-complexity reconfigurable antenna (RA) capable of steering its beam into nine different directions corresponding to $\theta =\lbrace -\text{42}^{\circ },0^{\circ },\text{42}^{\circ }\rbrace$ in the $\phi =\lbrace \text{25}^{\circ },0^{\circ },\text{155}^{\circ }\rbrace$ planes, and $\theta =\pm \text{25}^{\circ }$ in the $\phi =\text{90}^{\circ }$ plane, using a reduced number of switches is presented. The RA operating at $\text{3.4}\!-\! \text{3.8}$ GHz consists of a central dipole element excited by a coaxial probe, surrounded by four switchable parasitic dipoles located at different height levels above a ground plane, which acts as either a reflector for the elements located at an upper layer or a director for the ones at a lower layer, improving the radiation characteristics of the antenna. Each parasitic dipole is fed with a p-i-n diode as a switch, which enables the activation of these elements providing the desired modes of operation. The presented RA was manufactured and measured showing results with a good agreement with the theoretical and numerical simulation.