Abstract: A method and apparatus provides for improved imaging of objects underwater. The method and apparatus are particularly useful in a degraded underwater visual environment. The method and apparatus are also useful in undersea operations in which enhanced visualization at close range is desirable. Exemplary operations include diver assist, ship hull inspections, underwater robotic operations (e.g. sample collection, mine neutralization), etc.

Abstract: A method and apparatus provides for improved imaging of objects underwater. The method and apparatus are particularly useful in a degraded underwater visual environment. The method and apparatus are also useful in undersea operations in which enhanced visualization at close range is desirable. Exemplary operations include diver assist, ship hull inspections, underwater robotic operations (e.g. sample collection, mine neutralization), etc.

Abstract: Embodiments relate to compressive line sensing imaging. Initially, a codebook is configured with a pattern sequence for a series of illumination patterns. Each light element in an individually addressable laser diode array (IALDA) is independently controlled to project the series of illumination patterns onto a target. Next, measurements of the target are acquired based on the series of illumination patterns. The codebook is then used to decode the measurements to create an image of the target.

Abstract: Embodiments relate to compressive line sensing imaging. Initially, a codebook is configured with a pattern sequence for a series of illumination patterns. Each light element in an individually addressable laser diode array (IALDA) is independently controlled to project the series of illumination patterns onto a target. Next, measurements of the target are acquired based on the series of illumination patterns. The codebook is then used to decode the measurements to create an image of the target.

Abstract: A device for preventing unwanted electromagnetic inquiry of an electronic card storing information thereon by the transmission of a rogue interrogating signal from an RFID skimmer proximate the electronic card. The device comprises a first and a second conductive material layer each operating to detune an antenna associated with the electronic card or to detune front end resonant circuits associated with the electronic card, and one or more third material layers having a greater thickness than the first and second layers and disposed between the first and second layers, the one or more third material layers providing electromagnetic shielding against radio frequency signals emitted from the electronic card.

Abstract: A multimode antenna structure is described for a communications device. The communications device includes circuitry for processing signals communicated to and from the antenna structure. The antenna structure is configured for optimal operation in a given frequency range. The antenna structure includes a plurality of antenna ports operatively coupled to the circuitry, and a plurality of antenna elements, each operatively coupled to a different one of the antenna ports. Each of the plurality of antenna elements is configured to have an electrical length selected to provide optimal operation within the given frequency range. By way of one or more connecting elements, electrical currents on one antenna element flow to a connected neighboring antenna element and generally bypass the antenna port coupled to the neighboring antenna element.

Abstract: A multimode antenna structure is described for a communications device. The communications device includes circuitry for processing signals communicated to and from the antenna structure. The antenna structure is configured for optimal operation in a given frequency range. The antenna structure includes a plurality of antenna ports operatively coupled to the circuitry, and a plurality of antenna elements, each operatively coupled to a different one of the antenna ports. Each of the plurality of antenna elements is configured to have an electrical length selected to provide optimal operation within the given frequency range. By way of one or more connecting elements, electrical currents on one antenna element flow to a connected neighboring antenna element and generally bypass the antenna port coupled to the neighboring antenna element.

Abstract: An antenna system operative with a communications device for receiving a radio frequency signal, wherein the communications device produces a first control signal representing a frequency of a received signal. The antenna system comprises an antenna structure for receiving the radio frequency signal, the antenna structure comprising tunable elements for controlling a resonant frequency of the antenna structure; a decoder responsive to the first control signal for producing a second control signal and a switch matrix responsive to the second control signal for configuring one or more of the tunable elements to control the resonant frequency responsive to the frequency of the received signal.

Abstract: A communications apparatus comprising a first antenna, a first serial configuration of a first power amplifier and a first matching network, a second serial configuration of a second power amplifier and a second matching network, a switching element for switchably selecting the first or the second serial configuration for supplying a signal to the first antenna, the first and the second power amplifiers supplying a respective first signal of a first power and a second signal of a second power different than the first power to the first antenna for transmitting and the first and the second matching networks presenting respective first and second impedances to the respective first and second power amplifiers, the first and the second impedances responsive respectively to a power-related parameter of the first and the second signals.

Abstract: A communications device for receiving a propagating electromagnetic signal representing an information signal. The communications device comprises a first and a second radiator each comprising a plurality of structural elements; a controller for configuring one or more of the structural elements of the first radiator to produce first operating characteristics of the first radiator, the first radiator producing a first received signal responsive to the first operating characteristics; the controller for configuring one or more of the structural elements of the second radiator to produce second operating characteristics of the second radiator different than the first operating characteristics, the second radiator producing a second received signal responsive to the second operating characteristics and a signal processor responsive to at least one of the first and the second received signals for determining the information signal.

Abstract: One embodiment of the invention relates to an antenna providing a tunable resonant frequency within a low frequency band and further providing a high resonant frequency, the antenna comprises a first radiating structure of a first effective electrical length, a second radiating structure of a second effective electrical length having a fractional integer relationship to a wavelength related to the high resonant frequency and a variable reactance element connecting the first and the second radiating structures, wherein varying a reactance of the variable reactance element tunes the antenna within the low frequency band.

Abstract: A dual band antenna comprising structurally different antenna elements and having common feed. The antenna includes a ground plane, a radiating element and an arm extending from the radiating element. In a first operating mode energy is radiated from the arm, the radiating element and the ground plane. In a second operating mode energy is radiated from the radiating element and the ground plane. Thus the antenna operates in two modes with two different resonant frequencies.

Abstract: An antenna for a communications device having configurable elements controlled to modify an antenna impedance and/or an antenna resonant frequency to improve performance of the communications device. The antenna impedance is controlled to substantially match to an output impedance of a power amplifier that supplies the antenna with a signal for transmission. The antenna resonant frequency is controlled to overcome the effects of various operating conditions that can detune the antenna or in response to an operable frequency band.

Abstract: A radio frequency transmitting and receiving apparatus comprising a filter and an antenna, wherein the input reactance of the antenna is substantially equal in magnitude and opposite in sign to the output reactance of the filter. This reactance relationship permits the antenna and filter to be collocated and avoids transformation of the input and output impedances to the conventional 50 ohms such that the filter and antenna can be connected with a conventional 50 ohm transmission line.

Abstract: An active balancing system for rotating machinery is provided which is light weight, solid state and powered by radiant energy. One or more balance rings coupled to the rotating machinery each have balancing elements which are moved to a selected position by actuators whose operation is controlled according to measured vibration resulting from imbalance of the machinery. The actuators are powered by an electrical energy generating device, such as a photo cell or a photovoltaic element, which is coupled to the machinery and located across an air gap from a source of radiant energy such as an array of light emitting diodes.

Abstract: An antenna for a communications device having configurable elements controlled to modify an antenna impedance and/or an antenna resonant frequency to improve performance of the communications device. The antenna impedance is controlled to substantially match to an output impedance of a power amplifier that supplies the antenna with a signal for transmission. The antenna resonant frequency is controlled to overcome the effects of various operating conditions that can detune the antenna or in response to an operable frequency band.

Abstract: A wide band antenna. The antenna comprises a radiating element in a corner region of a substrate, spaced apart from a ground plane occupying a substantial portion of a remaining area of the substrate. Series and shunt impedance matching elements are connected to the radiating element to control the antenna operating parameters. The radiating element is connected to a signal feed.

Abstract: An antenna for transmitting and receiving radio frequency energy. The antenna comprises a conductive radiator comprising a first and a second conductive region for providing a first and a second current path length. A feed conductor and a ground conductor operate as meanderline (or slow wave) elements to provide an electrical length longer than a physical length.

Abstract: An antenna operative in a plurality of frequency bands. The antenna comprises first and second high band resonators, a resonating meanderline and a counterpoise. A ground return conductively couples one or more regions of the counterpoise to the meanderline. One or more of the first resonating element, the second resonating element and the resonating meanderline are coupled by magnetic and/or capacitive coupling to provide operation in the plurality of frequency bands.

Abstract: A radio frequency transmitting and receiving apparatus comprising an antenna further comprising a plurality of antenna segments. Each segment exhibits a different electrical length and certain of the segments are capacitively coupled to establish a resonant frequency for each segment. In one embodiment, the certain segments comprise a plurality of concentric arcuate conductive elements connected to a signal terminal and a ground plane.