77 GHz reconfigurable reflectarray with nematic liquid crystal

A 77 GHz liquid crystal microstrip reflectarray with beam reconfiguration capability in one dimension is presented. The free-standing reflector (without feed) has been characterized with respect to its reflection phase and magnitude. While it is possible to tune the reflection phase through almost 300°, the associated reflection losses are still quite high. Nevertheless the pattern measurements of the reflectarray showed distinct beam collimation towards different angles when appropriate DC control voltages are applied.