Voltage Controlled Intertwined Spiral Arrays for Reconfigurable Metasurfaces
Layout of array portion of sample free-standing bistate interwoven 7-fold quadrifilar spiral elements. The reference basic spirals in adjacent unit cells are alternatively marked dark and light grey to highlight the intertwining scheme. Four pin diodes are connected across breaks in the outer folds of the spiral conductors and the RF choke inductances are placed at the centre of each unit cell between the open ends of the spiral arms extended from adjacent unit cells. Geometrical parameters of the unit cell: lattice period mm, spiral pitch 1.6 mm, and strip width mm and thickness 17.5 m.