Abstract: An active biconical antenna and a receive array comprising a combination of active biconical and Vivaldi antennas. In one configuration, the active biconical antenna includes upper and lower cones. Each cone has a respective truncated apex. First and second feed points are respectively connected to the truncated apexes of the upper and lower cones and to first and second conductors. The active biconical antenna further includes a buffer amplifier having respective input terminals connected to the first and second conductors. The buffer amplifier has an input impedance that is impedance matched to an antenna impedance at and above but not below a frequency fc and is higher than the antenna impedance at frequencies substantially less than fc. The buffer amplifier also has an output impedance that is impedance matched to a system impedance at frequencies both above and below fc. A length of the first and second conductors is less than a wavelength at the frequency fc.

Abstract: An active biconical antenna and a receive array comprising a combination of active biconical and Vivaldi antennas. In one configuration, the active biconical antenna includes upper and lower cones. Each cone has a respective truncated apex. First and second feed points are respectively connected to the truncated apexes of the upper and lower cones and to first and second conductors. The active biconical antenna further includes a buffer amplifier having respective input terminals connected to the first and second conductors. The buffer amplifier has an input impedance that is impedance matched to an antenna impedance at and above but not below a frequency fc and is higher than the antenna impedance at frequencies substantially less than fc. The buffer amplifier also has an output impedance that is impedance matched to a system impedance at frequencies both above and below fc. A length of the first and second conductors is less than a wavelength at the frequency fc.

Abstract: A system may include a fastener having a trench formed in a side of a head of the fastener. The system may further include a magneto-elastic component spanning the trench and attached to the head of the fastener on both sides of the trench. The system may also include a coil wrapped around the magneto-elastic component between both sides of the trench. The system may include a radio frequency identification (RFID) circuit, where the coil may be electrically connected to the RFID circuit resulting in a resonance response frequency that is a function of a strain level applied to the magneto-elastic component.

Abstract: A method and apparatus for enhancing the sensitivity of an oscillator circuit functioning, in use, to sense changes in the inductance of inductive elements and/or the capacitance of capacitive elements coupled to said oscillator circuit. The oscillator circuit is coupled to a nonlinear resonator for generating a comb of frequencies in response to a drive frequency generated by the oscillator circuit, the comb of frequencies having at least a portion of at least one tooth for which an absolute value of the first derivative of the drive frequency with respect to said comb frequency is less than 1.0, comparing an output of the nonlinear resonator with an output of a reference oscillator for detecting changes in the drive signal of the oscillator circuit as enhanced by the slope of the at least a portion of at least one tooth for which the absolute value of the first derivative of the drive frequency with respect to said comb frequency is less than 1.0.

Abstract: A system for an antenna for very low frequency communication includes a surface platform that is configured to move on a surface or to be stationary on the surface, a first conductive cable having a first end coupled to the surface platform, wherein the first conductive cable is electrically conductive, and an aerial platform coupled to a second end of the first conductive cable, wherein the aerial platform comprises an electrically conductive portion electrically coupled to the first conductive cable, wherein for a moving surface platform the aerial platform is towed and has an elevation above the surface, and wherein for a stationary surface platform the aerial platform flies an orbital path above the surface platform.

Abstract: A distributed transmitter antenna includes a plurality of antenna segments and a plurality of transmitters. A first transmitter of the plurality of transmitters is coupled to a first antenna segment of the plurality of antenna segments, and a second transmitter of the plurality of transmitters is coupled to the first antenna segment and a second antenna segment of the plurality of antenna segments.

Abstract: A wireless radio-frequency identification (RFID) strain sensor including: a substrate; an antenna on the substrate; and an integrated circuit on the substrate and electrically connected to the antenna. At least one of the substrate and the antenna includes a magnetoelastic material.

Abstract: An antenna system having at least one active element with a first end thereof for connection to a radio receiver, transmitter or transceiver and at least one electromechanical resonator connected in series with (i) at least portion of said at least one active element and at least another portion of said at least one active element or (ii) said at least one active element and said radio receiver, transmitter or transceiver. The at least one active element exhibits capacitive reactance at an intended frequency of operation and the at least one electromechanical resonator exhibits inductive reactance at the intended frequency of operation, the inductive reactance of the at least one electromechanical resonator offsetting or partially offsetting the capacitive reactance of the at least one antenna element at the intended frequency of operation.

Abstract: A system may include a fastener having a trench formed in a side of a head of the fastener. The system may further include a magneto-elastic component spanning the trench and attached to the head of the fastener on both sides of the trench. The system may also include a coil wrapped around the magneto-elastic component between both sides of the trench. The system may include a radio frequency identification (RFID) circuit, where the coil may be electrically connected to the RFID circuit resulting in a resonance response frequency that is a function of a strain level applied to the magneto-elastic component.

Abstract: A system includes a fastener and a magneto-elastic component connected to the fastener, wherein a strain level applied to the magneto-elastic component is a function of a tightness level within a range of tightness levels of the fastener. The system further includes a radio frequency identification (RFID) circuit. The system also includes an antenna electrically connected to the RFID circuit. The system includes a variable inductor circuit electrically connected to the RFID circuit and to the antenna, where an inductance exhibited by the variable inductor circuit is a function of the strain level applied to the magneto-elastic component, where a resonance response frequency of the RFID circuit is a function of the inductance exhibited by the variable inductor circuit, and where a change in the strain level results in a shift in the resonance response frequency.

Abstract: A system includes a fastener and a magneto-elastic component connected to the fastener, wherein a strain level applied to the magneto-elastic component is a function of a tightness level within a range of tightness levels of the fastener. The system further includes a radio frequency identification (RFID) circuit. The system also includes an antenna electrically connected to the RFID circuit. The system includes a variable inductor circuit electrically connected to the RFID circuit and to the antenna, where an inductance exhibited by the variable inductor circuit is a function of the strain level applied to the magneto-elastic component, where a resonance response frequency of the RFID circuit is a function of the inductance exhibited by the variable inductor circuit, and where a change in the strain level results in a shift in the resonance response frequency.

Abstract: A wideband active antenna system comprising an antenna having N outputs and a nominal bandwidth, each of the N outputs being directly coupled to an associated buffer amplifier, with a distance between the N outputs and a first active stage of each associated buffer amplifier preferably being maintained as short as reasonably possible and preferably no greater than ¼ wavelength of any transmission and/or receiving frequency of the wideband active antenna system and/or preferably no greater than 0.1 wavelength of any transmission and/or receiving frequency in an extension band of frequencies lower than a lowest frequency in the nominal bandwidth of the antenna.

Abstract: A wideband active antenna system comprising an antenna having N outputs and a nominal bandwidth, each of the N outputs being directly coupled to an associated buffer amplifier, with a distance between the N outputs and a first active stage of each associated buffer amplifier preferably being maintained as short as reasonably possible and preferably no greater than ¼ wavelength of any transmission and/or receiving frequency of the wideband active antenna system and/or preferably no greater than 0.1 wavelength of any transmission and/or receiving frequency in an extension band of frequencies lower than a lowest frequency in the nominal bandwidth of the antenna.

Abstract: An antenna system having at least one active element with a first end thereof for connection to a radio receiver, transmitter or transceiver and at least one electromechanical resonator connected in series with (i) at least portion of said at least one active element and at least another portion of said at least one active element or (ii) said at least one active element and said radio receiver, transmitter or transceiver. The at least one active element exhibits capacitive reactance at an intended frequency of operation and the at least one electromechanical resonator exhibits inductive reactance at the intended frequency of operation, the inductive reactance of the at least one electromechanical resonator offsetting or partially offsetting the capacitive reactance of the at least one antenna element at the intended frequency of operation.

Abstract: A reconfigurable electro-magnetic tile includes a laser layer including a plurality of lasers, and a pixelated surface comprising a plurality of metal patches and a plurality of switches, wherein each respective switch of the plurality of switches is in a gap between a first respective metal patch and a second respective metal patch, wherein each respective switch is optically coupled to at least one respective laser of the plurality of lasers, and wherein each switch of the plurality of switches comprises a phase change material.

Abstract: A reconfigurable radio frequency aperture including a substrate, a plurality of reconfigurable patches on the substrate, and a plurality of reconfigurable coupling elements on the substrate, wherein at least one reconfigurable coupling element is coupled between a reconfigurable patch and another reconfigurable patch, and wherein the reconfigurable coupling elements affect the mutual coupling between reconfigurable patches.

Abstract: A thermomagnetic temperature sensor, a temperature measurement system and a method of measuring temperature employ a temperature-dependent resonant frequency of a thermomagnetic resonator to measure temperature. The thermomagnetic temperature sensor includes a thermomagnetic inductor and a capacitor connector to form the thermomagnetic resonator. The thermomagnetic inductor includes a ferromagnetic material having a temperature-dependent magnetic permeability to determine the temperature-dependent resonant frequency. A predetermined relationship between the temperature-dependent resonant frequency and temperature in a range between a maximum magnetic permeability value and a Curie temperature provides the measurement of temperature.

Abstract: The disclosed antenna structures and electronic microsystems are capable of physically disappearing in a controlled, triggerable manner. Some variations provide an on-chip transient antenna comprising a semiconductor substrate containing ion-implanted hydrogen atoms and a conductor network comprising metals bridged by low-melting-temperature metals. Some variations provide an off-chip transient antenna comprising a flexible substrate containing a polymer, nanoporous silicon particles, and an oxidant for silicon, and a conductor network comprising metals bridged by low-melting-temperature metals. Other variations provide a method of introducing physical transience to a semiconductor integrated circuit, comprising thinning a substrate from the back side, implanting hydrogen ions into the thinned substrate to introduce latent structural flaws, depositing a semiconductor integrated circuit or sensor chip, and providing a controllable heating source capable of activating the latent structural flaws.

Abstract: A reconfigurable electro-magnetic tile includes a laser layer including a plurality of lasers, and a pixelated surface comprising a plurality of metal patches and a plurality of switches, wherein each respective switch of the plurality of switches is in a gap between a first respective metal patch and a second respective metal patch, wherein each respective switch is optically coupled to at least one respective laser of the plurality of lasers, and wherein each switch of the plurality of switches comprises a phase change material.

Abstract: An apparatus, system, and/or method are described to enable optically transparent reconfigurable integrated electrical components, such as antennas and RF circuits to be integrated into an optically transparent host platform, such as glass. In one embodiment, an Ag NW film may be configured as a transparent conductor for antennas and/or as interconnects for passive circuit components, such as capacitors or resistors. Ag NW may also be used as transmission lines and/or interconnect overlays for devices. A graphene film may also be configured as active channel material for making active RF devices, such as amplifiers and switches.