Abstract: A wireless communication system includes a transmitter configured to transmit at least first and second radio waves having respective different frequencies F1 and F2, an electrically conductive first passive substantially linear medium, an electrically conductive first passive substantially nonlinear medium disposed proximate the first passive substantially linear medium, and a first magnetic film covering at least a portion of the first passive substantially linear medium. When the transmitter transmits the first and second radio waves, the first passive substantially linear and nonlinear media receive the first and second radio waves and generate first and second signals propagating therein at the respective frequencies F1 and F2. At least one intermodulation signal having a frequency F3 equal to nF1+mF2, where m and n positive or negative integers, is generated in the first passive substantially nonlinear medium. The first magnetic film reduces the at least one intermodulation signal by at least 2 dB.

Abstract: A wireless communication system includes a transmitter configured to transmit at least first and second radio waves having respective different frequencies F1 and F2, an electrically conductive first passive substantially linear medium, an electrically conductive first passive substantially nonlinear medium disposed proximate the first passive substantially linear medium, and a first magnetic film covering at least a portion of the first passive substantially linear medium. When the transmitter transmits the first and second radio waves, the first passive substantially linear and nonlinear media receive the first and second radio waves and generate first and second signals propagating therein at the respective frequencies F1 and F2. At least one intermodulation signal having a frequency F3 equal to nF1+mF2, where m and n positive or negative integers, is generated in the first passive substantially nonlinear medium. The first magnetic film reduces the at least one intermodulation signal by at least 2 dB.

Abstract: A wireless communication system includes a transmitter configured to transmit at least first and second radio waves having respective different frequencies F1 and F2, an electrically conductive first passive substantially linear medium, an electrically conductive first passive substantially nonlinear medium disposed proximate the first passive substantially linear medium, and a first magnetic film covering at least a portion of the first passive substantially linear medium. When the transmitter transmits the first and second radio waves, the first passive substantially linear and nonlinear media receive the first and second radio waves and generate first and second signals propagating therein at the respective frequencies F1 and F2. At least one intermodulation signal having a frequency F3 equal to nF1+mF2, where m and n positive or negative integers, is generated in the first passive substantially nonlinear medium. The first magnetic film reduces the at least one intermodulation signal by at least 2 dB.

Abstract: A fall arresting device including a device housing, a shaft within the housing, a rotor assembly rotatably connected to the shaft that includes a drum and a disc having at least one region of a ferromagnetic material, an extendable lifeline connected to the drum, a magnetic sensor positioned stationary relative to the device housing and adjacent to the disc, and a that includes a hard-magnetic material. The magnet positioned stationary relative the device housing and the magnetic sensor, where the magnetic sensor is configured to detect a change in a magnetic field produced by the magnet when the disc rotates about the shaft, the change in the magnetic field induced by the at least one region of the ferromagnetic material being brought within close proximity to the magnet as the disc rotates.

Abstract: A magnetic film assembly includes a coil having a plurality of turns defining a first major boundary surface of the coil, such that when energized, the coil generates an in-plane magnetic field component in a region of interest in air proximate and substantially parallel to the first major boundary surface, the in-plane magnetic field component having a magnetic field strength H that varies between a maximum Hmax and about 10% of Hmax in the region of interest in air; and a magnetic layer disposed on the coil so as to include the region of interest, such that when energized, the coil generates a magnetic field inducing an in-plane magnetic flux density B in the magnetic layer in the region of interest that varies less than about 5% in the region of interest.

Abstract: A device is described having one or more conductive loops to produce an electromagnetic field, such as for wireless power transfer to an electronic device. In some examples, an antenna is used with at least one resonating capacitor ring that is relatively co-planar with the antenna, and that is magnetically coupled to the antenna but is not electrically powered by an external source. In addition, a device is described having two or more thin-film coils, each coil comprising a pair of terminals and at least one loop defining a plane and an interior region. In some examples, the planes of the two or more coils are disposed substantially parallel to one another, the interior regions of the two or more coils at least partially overlap one another, and the pairs of terminals of the antennae are electrically connected in parallel.

Abstract: Ultrathin and flexible electrical devices including circuit dies such as, for example, a capacitor chip, a resistor chip, and/or an inductor chip, and methods of making and using the same are provided. Circuit dies are attached to a major surface of a flexible substrate having channels Electrically conductive traces are formed in the channels, self-aligned with the circuit dies, and in direct contact with the bottom surface of the circuit dies.

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: Wireless sensing devices including stable near-field antennas are provided. A spacer layer is attached to a portion of the substrate adjacent to the antenna. The spacer layer has a thickness T, a relative permittivity k, and a figure of merit defined as the ratio of T (in micrometers) by k. The spacer layer has the figure of merit no less than 20 (micrometers).

Abstract: Wireless sensing devices including stable near-field antennas are provided. A spacer layer is attached to a portion of the substrate adjacent to the antenna. The spacer layer has a thickness T, a relative permittivity k, and a figure of merit defined as the ratio of T (in micrometers) by k. The spacer layer has the figure of merit no less than 20 (micrometers).

Abstract: A shielded antenna (100) includes a spiral antenna (110) and a shield (120) disposed on the spiral antenna. The spiral antenna comprises a plurality of substantially concentric loops. The shield comprises a plurality of electrically isolated electrically conductive segments forming a regular pattern, such that in a top plan view, at least one segment overlaps a portion of at least two loops, and at least one pair of adjacent conductive segments defines an electrically insulative gap therebetween.

Abstract: A fall arresting device including a device housing, a shaft within the housing, a rotor assembly rotatably connected to the shaft that includes a drum and a disc having at least one region of a ferromagnetic material, an extendable lifeline connected to the drum, a magnetic sensor positioned stationary relative to the device housing and adjacent to the disc, and a that includes a hard-magnetic material. The magnet positioned stationary relative the device housing and the magnetic sensor, where the magnetic sensor is configured to detect a change in a magnetic field produced by the magnet when the disc rotates about the shaft, the change in the magnetic field induced by the at least one region of the ferromagnetic material being brought within close proximity to the magnet as the disc rotates.

Abstract: A shielded antenna (100) includes a spiral antenna (110) and a shield (120) disposed on the spiral antenna. The spiral antenna comprises a plurality of substantially concentric loops. The shield comprises a plurality of electrically isolated electrically conductive segments forming a regular pattern, such that in a top plan view, at least one segment overlaps a portion of at least two loops, and at least one pair of adjacent conductive segments defines an electrically insulative gap therebetween.

Abstract: Ultra-high frequency (UHF) antenna tags are described. The antenna tag includes a sensor portion including terminals for attaching a chip and an antenna portion including first and second elements electrically connected to the sensor portion. At least one of the first and second elements includes at least one meandered portion. The sensor portion is responsive to a presence of a dielectric or magnetic material. The antenna tag is configured such that the antenna tag has an input impedance at the terminals substantially matched to a chip impedance. In some embodiments, the antenna tag has a directivity of at least 4 dBi in a predetermined direction and a radiation efficiency of at least 60 percent.

Abstract: A rectifier comprising a chain of transistors for RF-DC conversion. In order to compensate for the thresholds of the transistors, each transistor can be connected to a junction earlier or later in the chain. By using both p-type and n-type transistors in the same chain, the different types of transistors can be compensated in different directions allowing more transistors to be compensated. Additional transistors connected to the gates of transistors of the main chain can allow the transistors of the main chain to be forward compensated at one part of the input cycle and backward compensated in another part to minimize both the voltage threshold of the rectifier and the leakage current. The line for compensation of the voltage threshold during forward conduction can comprise a solid line or a transistor, and if a transistor is used it may be diode-connected.

Abstract: A rectifier comprising a chain of transistors for RF-DC conversion. In order to compensate for the thresholds of the transistors, each transistor can be connected to a junction earlier or later in the chain. By using both p-type and n-type transistors in the same chain, the different types of transistors can be compensated in different directions allowing more transistors to be compensated. Additional transistors connected to the gates of transistors of the main chain can allow the transistors of the main chain to be forward compensated at one part of the input cycle and backward compensated in another part to minimize both the voltage threshold of the rectifier and the leakage current. The line for compensation of the voltage threshold during forward conduction can comprise a solid line or a transistor, and if a transistor is used it may be diode-connected.