Abstract: A wake-up radio system in a wireless sensor network, the wake-up radio comprising: an analog front end configured to communicate with matching network; an analog to digital converter coupled to the analog front end; and a digital baseband coupled to the analog to digital converter, wherein the digital baseband outputs a fast wake-up signal and a secure wake-up signal, and wherein the wake-up radio listens to all channels simultaneously.

Abstract: A wake-up radio system in a wireless sensor network, the wake-up radio comprising: an analog front end configured to communicate with matching network; an analog to digital converter coupled to the analog front end; and a digital baseband coupled to the analog to digital converter, wherein the digital baseband outputs a fast wake-up signal and a secure wake-up signal, and wherein the wake-up radio listens to all channels simultaneously.

Abstract: A system for recording video in a wearable device is provided. The system includes: a barrel to provide mechanical support for one or more components in the system, a camera, disposed inside the barrel, wherein the camera includes a front lens with a field of view pointed to an onlooker outside of the wearable device, a cover glass mounted on the barrel, the cover glass configured to protect the front lens and one or more components in the system, a light emitting device, disposed inside the barrel, and a light pipe configured to receive a light from the light emitting device and to transmit the light through an overlap area on the cover glass and to the onlooker, when the camera is recording a scene outside of the wearable device, within the field of view, wherein the camera field of view comprises at least a portion of the overlap area.

Abstract: A wake-up radio system in a wireless sensor network, the wake-up radio comprising: an analog front end configured to communicate with matching network; an analog to digital converter coupled to the analog front end; and a digital baseband coupled to the analog to digital converter, wherein the digital baseband outputs a fast wake-up signal and a secure wake-up signal, and wherein the wake-up radio listens to all channels simultaneously.

Abstract: An optical module includes first and second transparent substrates and a spacer between the first and second transparent substrates, holding the first transparent substrate in proximity to the second transparent substrate, with first and second diffractive optical elements (DOEs) on respective faces of the first and second transparent substrates. At least first and second capacitance electrodes are disposed respectively on the first and second transparent substrates in proximity to the first and second DOEs. Circuitry is coupled to measure changes in a capacitance between at least the first and second capacitance electrodes.

Abstract: An optical module includes first and second transparent substrates and a spacer between the first and second transparent substrates, holding the first transparent substrate in proximity to the second transparent substrate, with first and second diffractive optical elements (DOEs) on respective faces of the first and second transparent substrates. At least first and second capacitance electrodes are disposed respectively on the first and second transparent substrates in proximity to the first and second DOEs. Circuitry is coupled to measure changes in a capacitance between at least the first and second capacitance electrodes.

Abstract: An optical module includes first and second transparent substrates and a spacer between the first and second transparent substrates, holding the first transparent substrate in proximity to the second transparent substrate, with first and second diffractive optical elements (DOEs) on respective faces of the first and second transparent substrates. At least first and second capacitance electrodes are disposed respectively on the first and second transparent substrates in proximity to the first and second DOEs. Circuitry is coupled to measure changes in a capacitance between at least the first and second capacitance electrodes.

Abstract: A method of geolocating comprises: receiving wirelessly, at an asset located on the Earth's surface and from at least two airborne aircraft, ADS-B signals, respectively; interpolating, using a Bayes filter, at least some state information of the at least two airborne aircraft based on the ADS-B signals, respectively; determining differences in received signal strength indicator (RSSI) values (RSSI-difference values) of successive aircraft-specific ADS-B signals, respectively; estimating, using a likelihood function, locations of the asset based on the RSSI-difference values, the ADS-B signals and the interpolated state information, respectively, thereby producing a set of estimated locations; and searching amongst the set to find one of the estimated locations that is regarded as being most likely to most accurately describe an actual position of the asset.

Abstract: An optical module includes a transparent substrate and a refractive optical element mounted on the substrate. A conductive heating trace is deposited on the substrate around the refractive optical element. A temperature sensor senses a temperature of the substrate. Control circuitry is coupled to the temperature sensor so as to measure a difference between the temperature of the substrate and a target operating temperature of the module, and to drive a current through the conductive heating trace, responsively to the difference, so as to heat the substrate to the target operating temperature.

Abstract: A method of operating an end node to communicate with a central node, the method comprising: wirelessly receiving, a beacon signal periodically-transmitted from the central node; each beacon signal denoting the start of a single frame; each frame being organized to include a downlink (DL) phase which precedes an uplink (UL) phase; and a payload of the beacon signal including an offset which represents a starting time of the UL phase. The method further comprises: generating a message; selecting, unbeknownst to the central node, at least one UL logical-channel, respectively; and wirelessly transmitting, during the UL phase, at least a portion of the message from the end node over the selected at least one UL logical-channel according to a slotted ALOHA technique.

Abstract: A method for production of an optoelectronic device includes fabricating a plurality of vertical emitters on a semiconductor substrate. Respective top surfaces of the emitters are bonded to a heat sink, after which the semiconductor substrate is removed below respective bottom surfaces of the emitters. Both anode and cathode contacts are attached to the bottom surfaces so as to drive the emitters to emit light from the bottom surfaces. In another embodiment, the upper surface of a semiconductor substrate is bonded to a carrier substrate having through-holes that are aligned with respective top surfaces of the emitters, after which the semiconductor substrate is removed below respective bottom surfaces of the emitters, and the respective bottom surfaces of the emitters are bonded to a heat sink.

Abstract: A method, of operating an end node to wirelessly communicate with a central node, includes: receiving wirelessly a current instance of a beacon signal periodically-transmitted from the central node; measuring a received power, PB-RX, of the beacon signal; reading locally-stored values of PB-TX and G representing a presumed transmitted power of the beacon signal and a performance goal of the end node, respectively; determining, for a given channel, a path loss, PL, based on the PB-RX and the PB-TX; and adaptively setting an energy level, EN-TX, of a forthcoming message to be transmitted from the end node by adaptively determining, based on PL and G, at least two of: a level of power, PN-TX; a forward error correction coding rate, c; and a spreading factor, SF; and a modulation format, M.

Abstract: An optical module includes first and second transparent substrates and a spacer between the first and second transparent substrates, holding the first transparent substrate in proximity to the second transparent substrate, with first and second diffractive optical elements (DOEs) on respective faces of the first and second transparent substrates. At least first and second capacitance electrodes are disposed respectively on the first and second transparent substrates in proximity to the first and second DOEs. Circuitry is coupled to measure changes in a capacitance between at least the first and second capacitance electrodes.

Abstract: A method of geolocating comprises: receiving wirelessly, at an asset located on the Earth's surface and from at least two airborne aircraft, ADS-B signals, respectively; interpolating, using a Bayes filter, at least some state information of the at least two airborne aircraft based on the ADS-B signals, respectively; determining differences in received signal strength indicator (RSSI) values (RSSI-difference values) of successive aircraft-specific ADS-B signals, respectively; estimating, using a likelihood function, locations of the asset based on the RSSI-difference values, the ADS-B signals and the interpolated state information, respectively, thereby producing a set of estimated locations; and searching amongst the set to find one of the estimated locations that is regarded as being most likely to most accurately describe an actual position of the asset.

Abstract: A method of operating an end node to communicate with a central node, the method comprising: wirelessly receiving, a beacon signal periodically-transmitted from the central node; each beacon signal denoting the start of a single frame; each frame being organized to include a downlink (DL) phase which precedes an uplink (UL) phase; and a payload of the beacon signal including an offset which represents a starting time of the UL phase. The method further comprises: generating a message; selecting, unbeknownst to the central node, at least one UL logical-channel, respectively; and wirelessly transmitting, during the UL phase, at least a portion of the message from the end node over the selected at least one UL logical-channel according to a slotted ALOHA technique.

Abstract: An optical module includes a transparent substrate and a refractive optical element mounted on the substrate. A conductive heating trace is deposited on the substrate around the refractive optical element. A temperature sensor senses a temperature of the substrate. Control circuitry is coupled to the temperature sensor so as to measure a difference between the temperature of the substrate and a target operating temperature of the module, and to drive a current through the conductive heating trace, responsively to the difference, so as to heat the substrate to the target operating temperature.

Abstract: A method for production of an optoelectronic device includes fabricating a plurality of vertical emitters on a semiconductor substrate. Respective top surfaces of the emitters are bonded to a heat sink, after which the semiconductor substrate is removed below respective bottom surfaces of the emitters. Both anode and cathode contacts are attached to the bottom surfaces so as to drive the emitters to emit light from the bottom surfaces. In another embodiment, the upper surface of a semiconductor substrate is bonded to a carrier substrate having through-holes that are aligned with respective top surfaces of the emitters, after which the semiconductor substrate is removed below respective bottom surfaces of the emitters, and the respective bottom surfaces of the emitters are bonded to a heat sink.

Abstract: A method, of operating an end node to wirelessly communicate with a central node, includes: receiving wirelessly a current instance of a beacon signal periodically-transmitted from the central node; measuring a received power, PB-RX, of the beacon signal; reading locally-stored values of PB-TX and G representing a presumed transmitted power of the beacon signal and a performance goal of the end node, respectively; determining, for a given channel, a path loss, PL, based on the PB-RX and the PB-TX; and adaptively setting an energy level, EN-TX, of a forthcoming message to be transmitted from the end node by adaptively determining, based on PL and G, at least two of: a level of power, PN-TX; a forward error correction coding rate, c; and a spreading factor, SF; and a modulation format, M.

Abstract: A method (of operating an end node) includes: wirelessly receiving an instance of a non-hopping beacon signal, B, periodically-transmitted from a central node; interpreting a frequency-block hopping guide (FBHG) according to FN(i) and IDCN thereby to determine a corresponding set, CSET(i), of at least two channels available to the end node for transmission, respectively, during frame FN(i); selecting, at least pseudo-randomly, at least one channel amongst the set CSET(i); and wirelessly transmitting at least one message from the end node using the at least one selected channel, respectively. Each instance B(i) includes: a corresponding frame number, FN(i); and an identification, IDCN, of the central node. The FBHG establishes: a total of L frames; a set of channels CSET for each frame, respectively; and that, for any two consecutive ones of the L frames, FN(j) and FN(j+1), the corresponding sets CSET(j) and CSET(j+1) will be different, CSET(j)?CSET(j+1).

Abstract: A method, of operating an end node to wirelessly communicate with a central node, includes: receiving wirelessly a current instance of a beacon signal periodically-transmitted from the central node; measuring a received power, PB-RX, of the beacon signal; reading locally-stored values of PB-TX and G representing a presumed transmitted power of the beacon signal and a performance goal of the end node, respectively; determining, for a given channel, a path loss, PL, based on the PB-RX and the PB-TX; and adaptively setting an energy level, EN-TX, of a forthcoming message to be transmitted from the end node based on PL and G.