Abstract: A tunable or dual-band antenna includes a ground plane, top plane, a cage structure, first and second half-loops, and a hybrid phase shifter. The cage structure is attached to the ground plane and the top plane that includes four leg structures in electrically-conductive contact with the top plane. The top plane is one of a cross-element with four equilateral elements, a cross-element with eight equilateral elements, or a disc element. The first and second half-loops are independent from each other, located diagonally to each other within the cage structure, and support transmitting and receiving an electromagnetic field orthogonal to each other. The hybrid phase shifter shifts a frequency of the first and second half-loops to 90° from each other. The ground plane has an inner ground plane with two or more capacitors embedded therein.

Abstract: A tunable or dual-band antenna includes a ground plane, top plane, a cage structure, first and second half-loops, and a hybrid phase shifter. The cage structure is attached to the ground plane and the top plane that includes four leg structures in electrically-conductive contact with the top plane. The top plane is one of a cross-element with four equilateral elements, a cross-element with eight equilateral elements, or a disc element. The first and second half-loops are independent from each other, located diagonally to each other within the cage structure, and support transmitting and receiving an electromagnetic field orthogonal to each other. The hybrid phase shifter shifts a frequency of the first and second half-loops to 90° from each other. The ground plane has an inner ground plane with two or more capacitors embedded therein.

Abstract: A tunable or dual-band antenna includes a ground plane, top plane, a cage structure, first and second half-loops, and a hybrid phase shifter. The cage structure is attached to the ground plane and the top plane that includes four leg structures in electrically-conductive contact with the top plane. The top plane is one of a cross-element with four equilateral elements, a cross-element with eight equilateral elements, or a disc element. The first and second half-loops are independent from each other, located diagonally to each other within the cage structure, and support transmitting and receiving an electromagnetic field orthogonal to each other. The hybrid phase shifter shifts a frequency of the first and second half-loops to 90° from each other. The ground plane has an inner ground plane with two or more capacitors embedded therein.

Abstract: A tunable or dual-band antenna includes a ground plane, top plane, a cage structure, first and second half-loops, and a hybrid phase shifter. The cage structure is attached to the ground plane and the top plane that includes four leg structures in electrically-conductive contact with the top plane. The top plane is one of a cross-element with four equilateral elements, a cross-element with eight equilateral elements, or a disc element. The first and second half-loops are independent from each other, located diagonally to each other within the cage structure, and support transmitting and receiving an electromagnetic field orthogonal to each other. The hybrid phase shifter shifts a frequency of the first and second half-loops to 90° from each other. The ground plane has an inner ground plane with two or more capacitors embedded therein.

Abstract: A method for active circuit antenna optimization includes recording a capacitance value at each frequency of a frequency range using one or more tuning capacitors, thereby generating a capacitor value frequency range. The method further includes creating one or more non-linear circuit designs in an RF circuit simulator. The one or more non-linear circuit designs match the capacitance value at each frequency of the frequency range recorded from the one or more tuning capacitors. The method then includes creating one or more non-linear circuits from the non-linear circuit design. Each tuning capacitor has a corresponding non-linear circuit where all the one or more non-linear circuits match the capacitor value frequency range of the one or more tuning capacitors.

Abstract: A tunable or dual-band antenna includes a ground plane, top plane, a cage structure, first and second half-loops, and a hybrid phase shifter. The cage structure is attached to the ground plane and the top plane that includes four leg structures in electrically-conductive contact with the top plane. The top plane is one of a cross-element with four equilateral elements, a cross-element with eight equilateral elements, or a disc element. The first and second half-loops are independent from each other, located diagonally to each other within the cage structure, and support transmitting and receiving an electromagnetic field orthogonal to each other. The hybrid phase shifter shifts a frequency of the first and second half-loops to 90° from each other. The ground plane has an inner ground plane with two or more capacitors embedded therein.

Abstract: A method for active circuit antenna optimization includes recording a capacitance value at each frequency of a frequency range using one or more tuning capacitors, thereby generating a capacitor value frequency range. The method further includes creating one or more non-linear circuit designs in an RF circuit simulator. The one or more non-linear circuit designs match the capacitance value at each frequency of the frequency range recorded from the one or more tuning capacitors. The method then includes creating one or more non-linear circuits from the non-linear circuit design. Each tuning capacitor has a corresponding non-linear circuit where all the one or more non-linear circuits match the capacitor value frequency range of the one or more tuning capacitors.

Abstract: A tunable or dual-band antenna includes a ground plane, top plane, a cage structure, first and second half-loops, and a hybrid phase shifter. The cage structure is attached to the ground plane and the top plane that includes four leg structures in electrically-conductive contact with the top plane. The top plane is one of a cross-element with four equilateral elements, a cross-element with eight equilateral elements, or a disc element. The first and second half-loops are independent from each other, located diagonally to each other within the cage structure, and support transmitting and receiving an electromagnetic field orthogonal to each other. The hybrid phase shifter shifts a frequency of the first and second half-loops to 90° from each other. The ground plane has an inner ground plane with two or more capacitors embedded therein.

Abstract: An antenna comprising: a solar collector; two conductive, orthogonal half-loops mounted to the solar collector such that the solar collector functions as a ground; an RF power source configured to feed RF power to each of the two half-loops having a 90-degree phase difference relative to each other; and a conductive cage structure surrounding the two half-loops, wherein the cage structure includes a conductive ring disposed above the center section, the conductive ring having an equilateral cross of conductive material disposed within the ring and supported by leg structures which are in electrically-conductive contact with the solar collector, and wherein each leg structure has attached thereto a non-Foster circuit having a negative impedance, wherein the non-Foster circuits are configured to actively load the cage structure such that the cage structure functions as an active, internal matching network for the antenna.

Abstract: An antenna comprising: a solar collector; two conductive, orthogonal half-loops mounted to the solar collector such that the solar collector functions as a ground; an RF power source configured to feed RF power to each of the two half-loops having a 90-degree phase difference relative to each other; and a conductive cage structure surrounding the two half-loops, wherein the cage structure includes a conductive ring disposed above the center section, the conductive ring having an equilateral cross of conductive material disposed within the ring and supported by leg structures which are in electrically-conductive contact with the solar collector, and wherein each leg structure has attached thereto a non-Foster circuit having a negative impedance, wherein the non-Foster circuits are configured to actively load the cage structure such that the cage structure functions as an active, internal matching network for the antenna.

Abstract: Methods of construction for acoustic and electrically amplified stringed musical instruments. The invention further relates to acoustic and electrically amplified stringed musical instruments comprising fiber-reinforced resin composite materials, where the instruments are provided with a sound-damping interior coating.

Abstract: Methods of construction for acoustic and electrically amplified stringed musical instruments. The invention further relates to acoustic and electrically amplified stringed musical instruments comprising fiber-reinforced resin composite materials, where the instruments are provided with a sound-damping interior coating.

Abstract: A compact and flat antenna that provides both Direct Broadcast Satellite and local off-air reception. The flat reflector is made of a composite material with multiple reflective radiating surfaces. The multi-stepped reflector combines both diffraction and refractive principals to collimate Radio Frequency signal waves to a short focal point. At the focal point a phase correcting splash plate and lens direct the RF signal through a low loss axis-fed circular waveguide and then to a low noise amplifier. This compact design reduces space, cost and over-all structure, which presents an aesthetically pleasing satellite communication antenna. The antenna aperture includes a VHF/UHF antenna element for reception of local and/or off-air broadcast TV signals eliminating the need and cost to install a separate antenna.