Tunable liquid crystal reflectarray with rectangular elements

A square and a rectangular microstrip patch element are designed and investigated in order to realize an electronically reconfigurable reflectarray antenna based on liquid crystals at Ka-Band. By using an equivalent circuit composed of lumped elements, reflection coefficient amplitudes, tunable phase ranges and losses of the designed elements are compared. As a result of the investigation, since the rectangular element has higher reflection amplitude, a tunable liquid crystal reflectarray antenna composed of rectangular elements is realized. The fabricated antenna has the ability of beam steering in one dimension. Tuning capability of the reflectarray antenna is presented by scanning the main beam from -20° to +20°.