Multi-state frequency switchable reflectarray antenna design

Most of the space applications require high gain beam scanning antennas. Reflector antennas are the most common type of antennas used for these applications. This work provides a novel design of planar reflector to be used in reflectarray antenna design with multi-state frequency switchable characteristics. Different configurations of slot embedded resonant patch elements have been proposed and multiple PIN diodes have been used in ON and OFF states to obtain frequency switching at different points. The design has been demonstrated to be operating in X-band frequency range where frequency tunability from 9.63 GHz to 8.10 GHz has been demonstrated using combination of rectangular slots and PIN diodes. Moreover the design provides 2ⁿ different states of diode switching (n is number of diodes) which can be used to obtain different resonant frequencies of planar reflectors. The frequency tunability and loss characteristics have been investigated which are affected by the electric field intensity and surface current density on the resonant patch elements of planar reflectors.