Tunable dual-band ferroelectric antenna

A method for transforming an antenna into an absorber for electromagnetic energy at a particular frequency comprising the steps of.

• providing a layer of ferroelectric material disposed on a feeder-resonator;
• providing a director-resonator disposed above said layer of ferroelectric material;
• and
• providing a bias voltage across said layer of ferroelectric material.

A tunable dual band antenna assembly comprising:

• an electrically conductive ground plane;
• a first substrate layer having a bottom surface overlying said ground plane and an opposing upper surface, wherein said first substrate layer includes a low dielectric material;
• an electrically conductive sheet overlying said opposing upper surface of said substrate layer;
• said electrically conductive sheet including a patch radiator and a microstrip feed therefor;
• wherein said patch radiator serves as a feeder radiator;
• a second substrate layer having one face positioned on top of said feeder radiator and an opposing face, said second substrate layer including a thin film ferroelectric material having a permittivity value much higher than that of said first substrate layer;
• an electrically conductive patch overlying said opposing face of said second substrate layer, wherein said electrically conductive patch is operable as a director and is fed through capacitive coupling of energy from said patch radiator;
• and
• means for applying a bias voltage across said second substrate layer.

A method for providing adaptive nulling at a particular frequency in a radiation pattern of an antenna comprising the steps of:

• providing an electrically conductive ground plane;
• providing a first substrate layer of dielectric material over the ground plane;
• providing a first electrically conductive sheet overlying a top of said first substrate layer, wherein said first electrically conductive sheet includes a feeder patch resonator and a microstrip feed therefor;
• providing a second substrate layer over said feeder patch resonator, wherein said second substrate layer inclues a tunable thin-film ferroelectric material;
• providing a second electrically conductive sheet overlying a top of said second substrate layer, wherein said second electrically conductive sheet includes a director-patch resonator;
• providing a bias voltage between said second electrically conductive sheet and said firt electrically conductive sheet;
• and
• providing a resistive layer defining a predetermined broken pattern thereon over said director-patch resonator.