Abstract: A gradient permittivity film comprises (a) a first permittivity layer comprising a first continuous matrix of a first material having a first relative permittivity (?r1) and a second component having a second relative permittivity (?r2) dispersed in the first continuous matrix, the first permittivity layer having a first effective layer relative permittivity (?1) and a thickness (T1); And (b) a second permittivity layer having a second effective layer relative permittivity (?2) and a thickness (T2) disposed on the first permittivity layer. T1=0.8(t1) to 1.2(t1), where t 1 = c 4 ? f ? ? 1 ; ? T 2 = 0.8 ( t 2 ) ? to 1.2 ( t 2 ) , where ? t 2 = c 4 ? f ? ? 2 .

Abstract: An electronic device may include first and second antennas formed from respective first and second segments of a housing. The first antenna may have a first feed coupled to the first segment by a first switch and coupled to the first segment by a first conductive trace. The second antenna may have a second feed coupled to the second segment by a second switch and coupled to the second segment by a second conductive trace. The first segment may be separated from the second segment by a single gap, a data connector may pass through the second segment, and the antennas may selectively cover a low band. Alternatively, the first segment may be separated from the second segment by a third segment and two gaps, the data connector may pass through the third segment, and the first and second antennas may concurrently cover the low band.

Abstract: Gradient permittivity films are described. In particular, gradient permittivity films including a plurality of layers each having a thickness where at least one layer is perforated and has a different air volume fraction from another of the plurality of layers by at least 0.05. Such films may be useful in improving the signal to noise ratio for transmitting and receiving units operating between 20 GHz and 300 GHz behind a protective cover.

Abstract: An electronic device may include first and second antennas formed from respective first and second segments of a housing. The first antenna may have a first feed coupled to the first segment by a first switch and coupled to the first segment by a first conductive trace. The second antenna may have a second feed coupled to the second segment by a second switch and coupled to the second segment by a second conductive trace. The first segment may be separated from the second segment by a single gap, a data connector may pass through the second segment, and the antennas may selectively cover a low band. Alternatively, the first segment may be separated from the second segment by a third segment and two gaps, the data connector may pass through the third segment, and the first and second antennas may concurrently cover the low band.

Abstract: An electronic device may include first and second antennas formed from respective first and second segments of a housing. The first antenna may have a first feed coupled to the first segment by a first switch and coupled to the first segment by a first conductive trace. The second antenna may have a second feed coupled to the second segment by a second switch and coupled to the second segment by a second conductive trace. The first segment may be separated from the second segment by a single gap, a data connector may pass through the second segment, and the antennas may selectively cover a low band. Alternatively, the first segment may be separated from the second segment by a third segment and two gaps, the data connector may pass through the third segment, and the first and second antennas may concurrently cover the low band.

Abstract: Radar standing wave dampening systems and components are described. In particular, systems and components including an absorber composite including at least one of ceramic filler, magnetic filler, or conductive filler materials are described. Such components can reduce the intensity of standing waves and may also be combined in systems with one or more gradient permittivity tapes or films.

Abstract: A gradient permittivity film comprises (a) a first permittivity layer comprising a first continuous matrix of a first material having a first relative permittivity (?r1) and a second component having a second relative permittivity (?r2) dispersed in the first continuous matrix, the first permittivity layer having a first effective layer relative permittivity (?1) and a thickness (T1); And (b) a second permittivity layer having a second effective layer relative permittivity (?2) and a thickness (T2) disposed on the first permittivity layer. T1=0.8(t1) to 1.2(t1), where t 1 = c 4 ? f ? ? 1 ; ? T 2 = 0.8 ( t 2 ) ? to 1.2 ( t 2 ) , where ? t 2 = c 4 ? f ? ? 2 .

Abstract: Techniques are described for monitoring and controlling fall protection equipment. For example, the techniques of this disclosure may be used to monitor the connection status of fall protection equipment, e.g., whether or not the fall protection equipment is connected to a support structure. The techniques described in the disclosure may determine whether the fall protection equipment is connected to a support structure based on changes in a resonant frequency of an electronic circuit of an inductive sensor within the fall protection equipment. The inductive sensor may be formed from sets of one or more coils, where a first set of one or more coils and a second set of one or more coils are wound in opposite directions.

Abstract: Techniques are described for monitoring and controlling fall protection equipment. For example, the techniques of this disclosure may be used to monitor the connection status of fall protection equipment, e.g., whether or not the fall protection equipment is connected to a support structure. The techniques described in the disclosure may determine whether the fall protection equipment is connected to a support structure based on changes in a resonant frequency of an electronic circuit of an inductive sensor within the fall protection equipment. The inductive sensor may be formed from sets of one or more coils, where a first set of one or more coils and a second set of one or more coils are wound in opposite directions.

Abstract: A gradient permittivity film comprises (a) a first permittivity layer comprising a first continuous matrix of a first material having a first relative permittivity (?r1) and a second component having a second relative permittivity (?r2) dispersed in the first continuous matrix, the first permittivity layer having a first effective layer relative permittivity (?1) and a thickness (T1); and (b) a second permittivity layer having a second effective layer relative permittivity (?2) and a thickness (T2) disposed on the first permittivity layer T1=0.8(t1) to 1.2(t1), where t1=(I); T2=0.8(t2) to 1.2 (T2), where T2=(II).

Abstract: This disclosure relates generally to radar retroreflective articles comprising one or more dielectric layers adjacent to a reflective layer, wherein the dielectric layer or layers aids in increasing the radar cross section of the radar retroreflective articles.

Abstract: A radar-optical fusion article for attachment to a substrate is described. The radar-optical fusion article includes a first retroreflective layer which is configured to retroreflect at least a portion of light having a wavelength in a range from about 400 nm to about 2500 nm. The radar-optical fusion article includes a second retroreflective layer disposed adjacent to the first retroreflective layer. The second retroreflective layer is configured to retroreflect at least a portion of an electromagnetic wave having a frequency in the range from about 0.5 GHz to about 100 GHz.

Abstract: This disclosure relates generally to radar retroreflective articles comprising one or more dielectric layers adjacent to a reflective layer, wherein the dielectric layer or layers aids in increasing the radar cross section of the radar retroreflective articles.

Abstract: A method for monitoring the surface of a device to physical and/or environmental exposure, the method comprising: • (a) attaching at least one sensor including a reactance autotuning integrated circuit to a surface of a device; • (b) attaching a reader in proximity to the sensor; • (c) measuring a reference reactance of the sensor with the reader at a selected frequency; • (d) continually monitoring for changes in the reactance of the sensor at the selected frequency, wherein changes to the reactance are digitized by the autotuning circuit; and • (e) comparing differences between the reference reactance and changes to the monitored reactance to determine if said surface of the device has been subjected to physical and/or environmental exposure.

Abstract: A gradient permittivity film comprises (a) a first permittivity layer comprising a first continuous matrix of a first material having a first relative permittivity (?r1) and a second component having a second relative permittivity (?r2) dispersed in the first continuous matrix, the first permittivity layer having a first effective layer relative permittivity (?1) and a thickness (T1); and (b) a second permittivity layer having a second effective layer relative permittivity (?2) and a thickness (T2) disposed on the first permittivity layer T1=0.8(t1) to 1.2(t1), where t1=(I); T2=0.8(t2) to 1.2 (T2), where T2=(II).

Abstract: Radar standing wave dampening systems and components are described. In particular, systems and components including an absorber composite including at least one of ceramic filler, magnetic filler, or conductive filler materials are described. Such components can reduce the intensity of standing waves and may also be combined in systems with one or more gradient permittivity tapes or films.

Abstract: Gradient permittivity films are described. In particular, gradient permittivity films that include a first continuous matrix of a first component having a first relative permittivity and a second component disposed within the continuous matrix having a second relative permittivity. The first permittivity is greater than the second permittivity for at least one wavelength between 20 GHz and 300 GHz. Such films may be useful in improving the signal to noise ratio for transmitting and receiving units behind a protective cover.

Abstract: Gradient permittivity films are described. In particular, gradient permittivity films including a plurality of layers each having a thickness where at least one layer is perforated and has a different air volume fraction from another of the plurality of layers by at least 0.05. Such films may be useful in improving the signal to noise ratio for transmitting and receiving units operating between 20 GHz and 300 GHz behind a protective cover.

Abstract: Techniques are described for monitoring and controlling fall protection equipment. For example, the techniques of this disclosure may be used to monitor the connection status of fall protection equipment, e.g., whether or not the fall protection equipment is connected to a support structure. The techniques described in the disclosure may determine whether the fall protection equipment is connected to a support structure based on changes in a resonant frequency of an electronic circuit of an inductive sensor within the fall protection equipment. The inductive sensor may be formed from sets of one or more coils, where a first set of one or more coils and a second set of one or more coils are wound in opposite directions.

Abstract: A system for use in wirelessly monitoring a pipeline such as a natural gas pipe. The system includes a locator configured to wirelessly transmit power and a subsoil sensor marker located adjacent the pipe and configured to wirelessly communicate with the locator. The sensor marker includes a microcontroller, a memory module, a sensor configured to sense the presence of a gas, and a power module. The power module is configured to harvest a sufficient amount of the power wirelessly transmitted from the locator in order to operate the microcontroller to take a measurement via the sensor, save the measurement in the memory module, and wirelessly transmit the measurement to the locator.