Tunable reduced weight artificial dielectric antennas

A frequency selective surface in an anisotropic artificial dielectric material adapted to form the substrate of a resonator, comprising:

• a plurality of variable capacitors arranged in the frequency selective surface so as to be coupled between a radiating element and a ground plane of the resonator, a relative permittivity of the artificial dielectric material being tunable by controlling the amount of electric field stored in the variable capacitors.

A frequency selective surface in an anisotropic artificial dielectric material adapted to form the substrate of a resonator, comprising:

• a plurality of variable capacitors arranged in the frequency selective surface so as to be coupled between a radiating element and a ground plane of the resonator;
• and
• a plurality of bias resistors connected to each other in series, each resistor being connected in parallel to a corresponding one of the plurality of variable capacitors so that a substantially equal reverse bias voltage is provided across each diode by a voltage division between each of the bias resistors.

A frequency selective surface in an anisotropic artificial dielectric material adapted to form the substrate of a resonator, comprising:

• a plurality of variable capacitors arranged in the frequency selective surface so as to be coupled between a radiating element and a ground plane of the resonator;
• and
• a plurality of bias and decoupling resistors connected so as to form two distinct ladder networks, wherein one ladder network is grounded and has nodes which connect to the cathode of each of the variable capacitors, and wherein the second ladder network is held at an intended reverse bias potential for each of the variable capacitors, and has nodes which connect to the anode of each of the variable capacitors.

A frequency selective surface in an anisotropic artificial dielectric material adapted to form the substrate of a resonator, comprising:

• a plurality of variable capacitors arranged in the frequency selective surface so as to be coupled between a radiating element and a ground plane of the resonator,
• wherein the plurality of variable capacitors are connected in series in a direction between the radiating element and the ground plane, the direction corresponding to a dominant electric field component of the resonator.

A frequency selective surface in an anisotropic artificial dielectric material adapted to form the substrate of a resonator, comprising:

• a plurality of variable capacitors arranged in the frequency selective surface so as to be coupled between a radiating element and a ground plane of the resonator,
• wherein the plurality of variable capacitors are disposed in a respective plurality of positions of the substrate, the respective positions being determined in accordance with respective magnitudes of a dominant mode electric field of the resonator at the plurality of positions.