Abstract: A testing apparatus for dynamic characterization of a sample of a material under test. A terahertz (THz) time-domain spectroscopy system is configured and arranged to generate and detect terahertz waves to interrogate the sample. A shock wave loading system is configured and arranged to produce a shock wave in the sample concurrently with said THz spectroscopy device interrogating the sample. The sample undergoes changes in an index of refraction in response to the produced ultrafast shock wave in the sample that are detected by the terahertz spectroscopy system.

Abstract: A method for configuring a multi-mode antenna system is provided. The method includes obtaining channel selection data indicating the antenna system is tuned to a first channel of a plurality of channels. The method includes configuring the antenna system in at least one operating mode of a plurality of operating modes, with each operating mode of the plurality of operating modes having a distinct radiation pattern. The method includes obtaining data indicative of a channel quality indicator for the at least one operating mode. The method includes determining a selected operating mode for the multi-mode antenna system for the first channel of the plurality of channels based, at least in part, on the data indicative of the channel quality indicator. The method includes configuring the antenna system in the selected operating mode when the multi-mode antenna system is tuned to the first channel.

Abstract: A cellular repeater system is provided. The cellular repeater system includes an outdoor antenna communicatively coupled to a repeater. The outdoor antenna is configured to relay communications from the repeater to a cellular base station. The outdoor antenna includes a plurality of log-periodic antennas rotated relative to one another such that each of the plurality of log-periodic antennas is pointed in a different direction. The cellular repeater system includes a switching device configured to selectively couple one or more of the plurality of log-periodic antennas to a RF transceiver of the repeater in order to configure the outdoor antenna in a plurality of antenna modes. Each of the plurality of antenna modes have a distinct radiation pattern.

Abstract: Non-conductive films for constructing lighter than air balloons are provided. A non-conductive film may comprise multiple layers of gas barrier polymers. An outer surface printable layer and an interior heat or ultrasonically sealable layer may also be included. Each gas barrier film may comprise multiple (e.g., from 3 to approximately 75) barrier layers. A gas barrier core has a nano-layer structure. A gas barrier core may also comprise a biodegradable film or a bio-based film. A non-conductive film may comprise a metal layer for enhancing gas barrier properties. The metal layer may be discontinuous. The metal layer may be conductive and coated with an insulating top coat.

Abstract: A communication system for point to multipoint communications by grouping client devices based on associated modes is provided. In one example implementation, point to multipoint communication improvements are achieved by grouping a plurality of client devices by their optimal modes for communication. For example, the communication system can determine, based on channel quality indicators (CQIs) that two client devices of a plurality of client devices are associated with an optimal first mode of a modal antenna. The system can group the two client devices into a first group, the first group associated with communication using the first mode of the modal antenna. The modal antenna can communicate with the first group using the first mode of a modal antenna during a single frame of communication.

Abstract: An antenna system is provided. The antenna system includes a modal antenna disposed on a circuit board. The modal antenna includes a driven element and a parasitic element. The modal antenna is operable in a plurality of different modes. Each of the plurality of modes has a distinct radiation pattern. The antenna system further includes a radio frequency amplifier circuit disposed on the circuit board. The radio frequency amplifier circuit is coupled between the drive element of the modal antenna and a transmission line.

Abstract: A device includes a plurality of antennas, including one or more active antennas, the antennas being configured in one of a plurality of possible configurations to achieve operation in WAN, LTE, WiFi, or WiMax bands, or a combination thereof. In some embodiments, a passive antenna is utilized with lumped loading to fix the antenna tuning state. A primary and auxiliary radiator can be included in the device and configured for WAN/LTE bands, while additional antennas can be incorporated for WiFi and WiMax bands. Various antenna configurations incorporate the antenna having multiple coupled regions.

Abstract: Systems and methods for point to multipoint communications are provided. In one example, a system includes one or more modal antennas. Each modal antenna is configured to operate in a plurality of modes. The system can include a transceiver configured to communicate with a plurality of client devices over a wireless communication medium via the one or more modal antennas over a plurality of frames. The system can include one or more control devices configured to control the operation of the one or more modal antennas. For each of the plurality of frames communicated to one of the plurality of client devices, the one or more control devices are configured to determine a selected mode of the plurality of modes to communicate during the frame and to operate at least one of the one or more modal antennas in the selected mode during the frame.

Abstract: A millimeter wave RF phase shifter includes an input and an output. The RF phase shifter further includes a transmission line coupled to the input. The transmission line can include a plurality of taps. The RF phase shifter can further include a plurality of switching devices. Each switching device can be coupled between the output and a corresponding tap of the plurality of taps. The RF phase shifter can include a control device operatively coupled to the plurality of switching devices. The control device can be configured to control operation of the plurality of switching devices to selectively couple one of the plurality of taps to the output to control a phase shift of a RF signal propagating on the transmission line.

Abstract: Systems, apparatus, and methods for channel estimation and data detection. In one exemplary embodiment, the data is obtained in a two-phase transmission structure that alternates known data with unknown data according to a regular or otherwise pre-determined time interval. Then, the receiver iteratively updates a postulated channel, and provides a predicted channel to the next time slot. Conceptually, the exemplary techniques iteratively improve its postulates for channel condition and data over multiple time slots. More directly, instead of linear detection and decoding of a pilot for channel estimation in each time slot, the exemplary techniques described herein use postulated channel conditions to attempt data detection and use the recovered data from data detection (unknown data) to re-postulate the channel conditions, etc. until channel conditions are stable and/or the next time slot is ready for processing.

Abstract: A circularly polarized array antenna is provided. The circularly polarized array antenna includes a ground plane and a plurality of circularly polarized antennas. Each of the circularly polarized antennas is configured to communicate over a frequency band ranging from 24 gigahertz (GHz) to 52 GHz. Each of the circularly polarized antennas includes a column substrate coupled to the ground plane. The column substrate includes a plurality of faces. Each of the circularly polarized antennas further includes a plurality of isolated magnetic dipole elements. Each of the isolated magnetic dipole elements is disposed on a different face of the column substrate.

Abstract: Non-conductive films for constructing lighter than air balloons are provided. A non-conductive film may include multiple layers of gas barrier polymers. An outer surface printable layer and an interior heat or ultrasonically sealable layer may also be included. Each gas barrier film may include multiple (e.g., from 3 to approximately 75) barrier layers. A gas barrier core has a nano-layer structure. A gas barrier core may also include a biodegradable film or a bio-based film. A non-conductive film may include a metal layer for enhancing gas barrier properties. The metal layer may be discontinuous. The metal layer may be conductive and coated with an insulating top coat.

Abstract: A method of forming a multi-layer circuit on a curved substrate includes forming, by a laser direct structuring process, a first layer of the multi-layer circuit on a first surface of the curved substrate. The method includes applying a first layer of paint to the first layer of the multi-layer circuit. The method includes forming, by the laser direct structuring process, a second layer of the multi-layer circuit on the first layer of the paint and electrically coupled to the first layer of the multi-layer circuit. The method includes applying a second layer of paint over the second layer of the multi-layer circuit and forming, by the laser direct structuring process, a third layer of the multi-layer circuit on the second layer of the paint and electrically coupled to the second layer of the multi-layer circuit.

Abstract: A system for communicating data over a transmission line is disclosed. In one example implementation, the system may include a transmitter configured to modulate a control signal onto an RF signal using amplitude-shift keying modulation to generate a transmit signal. The system may include a receiver and a transmission line coupling the transmitter to the receiver. The transmitter may be configured to transmit the transmit signal over the transmission line to the receiver, and the receiver may be configured to de-modulate the control signal and extract clock information associated with the transmitter. In some embodiments, the system may include a tuning circuit and a modal antenna, and the tuning circuit may be or include the receiver. The receiver may be configured to adjust a mode of the modal antenna based on the control signal transmitted by the transmitter.

Abstract: An antenna system, such as a multifeed antenna system, can include at least one antenna feed element. The antenna system can include an antenna loop element. The at least one antenna feed element can be capacitively coupled to the antenna loop element. The at least one antenna feed element can include one or more capacitively coupled regions. The one or more capacitively coupled regions can form at least a portion of the capacitive coupling of the at least one antenna feed element to the antenna loop element.

Abstract: An antenna system can include an antenna array having a plurality of antenna elements. The antenna system can include an array controller configured to control operation of the antenna array for beam forming of the antenna array. The antenna system can include a radiofrequency circuit. The antenna system can include a transmission line coupling the radiofrequency circuit to the array controller. The transmission line can be configured to carry a radio-frequency signal to the antenna array. The radiofrequency circuit can be configured to modulate an antenna array control signal onto the radiofrequency signal to generate a transmit signal for communication over the transmission line to the array controller. The array controller can be configured to demodulate the antenna array control signal from the transmit signal such that the array controller is configured to control operation of the antenna array based at least in part on the antenna array control signal.

Abstract: An antenna system can include a ground plane and a driven element spaced apart from the ground plane. The antenna system can include a parasitic element disposed proximate to the driven element. The parasitic element can be coupled to the ground plane by a first coupling and a second coupling. The second coupling can be independent from the first coupling. For instance, the first coupling can include one or more tunable components. The second coupling can fix the parasitic element to the ground plane.

Abstract: Methods directed to finding algorithms designed to estimate the angle of arrival of signals incoming to a communication device by using a modal antenna having multiple radiation patterns are provided. In particular, a method can include obtaining a gain variation between adjacent modes of a plurality of antenna modes at each of a plurality of angles. The method can include obtaining a signal strength variation between the adjacent modes at each of the plurality of angles. The method can include determining a difference value based, at least in part, on the gain variation and the signal strength variation. The method can include determining an angle of arrival of the signal based, at least in part, on the difference value.

Abstract: An antenna-like matching component is provided, comprising one or more conductive portions formed on a substrate. Shapes and dimensions of the one or more conductive portions are determined to provide impedance matching for one or more antennas coupled to the matching component.

Abstract: A load balancing method for cellular communication systems and communication systems in general is described where beam steering antenna systems on the client or user side of the communication link are used to optimize load balancing among the base stations or nodes. A system controller containing an algorithm is implemented to control the radiation modes from the client or user devices to assign the client or user devices to the various base stations or nodes and to dynamically vary the network load across the cellular or communication system.