Abstract: A method for determining spin of a projectile comprising generating an electromagnetic radar signal and transmitting the electromagnetic radar signal towards a projectile. Receiving a reflected electromagnetic radar signal from the projectile. Identifying a component of the reflected electromagnetic radar signal, and performing an autocorrelation process on the reflected electromagnetic radar signal using the component to generate an estimate of a spin of the projectile as a function of the autocorrelation process.

Abstract: A LIDAR system includes at least one optical component configured to output a system output signal that travels away from the LIDAR system and can be reflected by an object located outside of the LIDAR system. The LIDAR system also includes a control mechanism configured to control one or more process variables of the system output signal. The control mechanism uses an electrical process variable signal to control the process variable. The process variable signal has an in-phase component and a quadrature component.

Abstract: A light detection and ranging (LiDAR) system according to the present disclosure comprises an optical circulator and one or more photodetectors (PDs). The optical circulator is to transmit the target return signal to the one or more PDs, where the one or more PDs are to mix the target return signal with a local oscillator (LO) signal to generate a signal to extract information of the target.

Abstract: A LIDAR system comprising a laser configured to output a beam, a modulator configured to receive the beam and modulate the beam to generate a modulated beam, a photonic integrated circuit having an amplifier coupled to receive the modulated beam from the modulator and generate an amplified beam, the amplifier having an active layer and an alternating or periodic or a super lattice structure configured to dissipate heat; and a transceiver chip coupled to the photonic integrated circuit, the transceiver chip configured to emit the amplified beam and receive a reflected beam from a target.

Abstract: A peripheral perception system for providing a 360-coverage of a peripheral region around a machine is disclosed. The peripheral perception system includes a first perception device mounted to a first surface of the machine, defining a first elevation and a first angle with respect to a vertical axis of the machine; and a second perception device mounted to a second surface of the machine, defining a second elevation and a second angle with respect to the vertical axis. The first perception device scans a first field of view covering a first peripheral region of the machine and the second perception device scans a second field of view covering a second peripheral region of the machine, such that the first field of view and the second field of view combinedly provide 360-degree coverage of the peripheral region around the machine.

Abstract: A method implemented by a first time of flight (ToF) sensor includes generating, by the first ToF sensor, a first depth map in accordance with measurements of reflections of an optical signal emitted by the first ToF sensor; communicating, by the first sensor with a second ToF sensor, the first depth map and a second depth map, the second depth map generated by the second ToF sensor; and determining, by the first ToF sensor, a relative location of the first ToF sensor relative to the second ToF sensor in accordance with the first depth map and the second depth map.

Abstract: An axial deviation estimation apparatus of an in-vehicle sensor includes a road surface recognition unit configured to recognize a road surface by a laser radar installed in a vehicle, an estimation unit configured to estimate an axial deviation amount of the in-vehicle sensor mounted on the vehicle, and a plane creation unit configured to create a virtual plane of the road surface based on a recognition result of the road surface recognition unit. The estimation unit estimates the axial deviation amount based on an inclination of the virtual plane with respect to a reference plane of the laser radar.

Abstract: The imaging system includes a photonic circuit chip having multiple cores. Each of the cores includes an optical switch and multiple alternate waveguides. The optical switch in each core is configured to direct an outgoing light signal to any one of the alternate waveguides, the alternate waveguide to which the outgoing light signal is directed being an active waveguide. Each core outputs the outgoing LIDAR signal from the active waveguide while receiving an incoming LIDAR signal that includes light from the outgoing LIDAR signal, has exited from the imaging system, and has returned to the imaging system. Each core includes a signal splitter that receives the outgoing LIDAR signal and the incoming LIDAR signal. The signal splitter extracts a portion of the outgoing LIDAR signal that serves as a reference signal and at least a portion of the incoming LIDAR signal that serves as a comparative signal.

Abstract: An autonomous vehicle having a LIDAR system mounted thereon or incorporated therein is described. The LIDAR system has N channels, with each channel being a light emitter/light detector pair. A computing system identifies M channels that are to be active during a scan of the LIDAR system, wherein M is less than N. The computing system transmits a command signal to the LIDAR system, and the LIDAR system performs a scan with the M channels being active (and N-M channels being inactive). The LIDAR system constructs a point cloud based upon the scan, and the computing system controls the autonomous vehicle based upon the point cloud.

Abstract: At a preparatory step for correction, in a state that a reflective tape made with a retroreflective material is pasted in advance onto a floor surface of a measurement space in a direction away from the distance-measuring device, a distance La to an inside area of the reflective tape, and a distance Lb to an outside area of the reflective tape adjacent to the inside area are measured by the distance-measuring device, while measurement positions Y are being scanned along the reflective tape. A correction formula for converting the distance Lb to the distance La is created from a relationship between the distance La and the distance Lb obtained at each measurement position Y. At an actual measurement step, a distance (actual measurement value x) to the target object measured by the distance-measuring device is corrected in accordance with the correction formula, and a measurement-distance corrected value y is calculated.

Abstract: Techniques are disclosed for operating a time-of-flight (TOF) sensor. The TOF may be operated in a low power mode by repeatedly performing a low power mode sequence, which may include performing a depth frame by emitting light pulses, detecting reflected light pulses, and computing a depth map based on the detected reflected light pulses. Performing the low power mode sequence may also include performing an amplitude frame at least one time by emitting a light pulse, detecting a reflected light pulse, and computing an amplitude map based on the detected reflected light pulse. In response to determining that an activation condition is satisfied, the TOF may be switched to operate in a high accuracy mode by repeatedly performing a high accuracy mode sequence, which may include performing the depth frame multiple times.

Abstract: Apparatuses, systems and methods for modulating returned light for acquisition of 3D data from a scene are described. A 3D imaging system includes a Fabry-Perot cavity having a first partially-reflective surface for receiving incident light and a second partially-reflective surface from which light exits. An electro-optic material is located within the Fabry-Perot cavity between the first and second partially-reflective surfaces. Transparent longitudinal electrodes or transverse electrodes produce an electric field within the electro-optic material. A voltage driver is configured to modulate, as a function of time, the electric field within the electro-optic material so that the incident light passing through the electro-optic material is modulated according to a modulation waveform. A light sensor receives modulated light that exits the second partially-reflective surface of the Fabry-Perot cavity and converts the light into electronic signals.

Abstract: A method of measuring a distance between a vehicle and one or more objects, includes generating a modulation signal; generating a modulated light emitting diode (LED) transmission signal, via a vehicle LED driver assembly; transmitting a plurality of light beams based at least in part on the generated modulated LED transmission signal; capturing a reflection of the plurality of light beams off the one or more objects, utilizing one or more lens assemblies and a camera, the camera including an array of pixel sensors and being positioned on the vehicle; communicating a series of measurements representing the captured plurality of light beam reflections; calculating, utilizing the time-of-flight sensor module, time of flight measurements between the vehicle LED light assembly and the one or more objects and calculating distances, utilizing a depth processor module, between the vehicle LED light assembly and the one or more objects based on the time-of-flight measurements.

Abstract: A light detection and ranging (LIDAR) system for a vehicle, includes a laser source configured to generate light signals, a transceiver, and a fiber array coupled to the transceiver and including a plurality of output channels. The transceiver is configured to receive one or more light signals from the laser source through a first group of output channels of the fiber array, receive one or more local oscillator (LO) signals through a second group of output channels of the fiber array, transmit the one or more light signals into an environment of the vehicle, receive a first returned light reflected from one or more objects in the environment, and output the first returned light and a first LO signal of the one or more LO signals.

Abstract: Disclosed are a same-path and synchronous detection system and a same-path and synchronous detection method for atmosphere data. The detection system includes an emission unit, a receiving unit and a data processing unit, where the emission unit includes multiple sets of laser devices, which are used for emitting the laser of different wavelengths in a synchronous and same-path manner; the receiving unit includes a receiving telescope, which is symmetrically provided with a plurality of pupils, to receive an echo signal after the laser of different wavelengths interacts with the atmosphere; and the data processing unit is configured to calculate atmosphere data parameters through the echo signal. The synchronous and same-path detection for a plurality of atmosphere data parameters may be implemented in the present disclosure.

Abstract: A method for generating and distributing GNSS positioning correction data includes dividing a service area into plural virtual cells, locating a virtual RTK reference station in every virtual cell, collectively calculating interpolated correction data for virtual RTK reference stations using correction data of actual RTK reference stations, encoding any combination of correction data into a virtual cell RTK frame, and distributing or providing the virtual cell RTK frame to servers or user devices through networks. Cost-effectiveness of distribution (or service) network can be achieved by means of spatial and/or temporal optimization of correction data with a virtual cell map indicating validities of each virtual cell.

Abstract: A wideband interference mitigation module is coupled to an output of a primary downconverter to process the digital intermediate frequency signal. A selective filtering module is associated with a secondary downconverter that comprises a digital harmonic-resistant translator. The selective filtering module comprises: (a) a low-pass filter that is configured as an anti-aliasing digital filter consistent with a target receive bandwidth to suppress aliasing associated with the analog-to-digital conversion, and (b) narrow band rejection filter to filter the digital baseband signal to reduce or to mitigate electromagnetic interference, where the narrow band rejection filter is configured for adaptive control responsive to detection by the wideband interference mitigation module of certain interference in the received radio frequency signal.

Abstract: The disclosed technology for preparing digital samples for synthesis of RF to simulate channels and GNSS satellites using GPUs includes receiving simulated position and velocity of an antenna, dividing the cycle into points to be converted into the synthesized signal, and computing the points. A first LUT includes pseudo random sequences combinable to produce a code that varies over time for encoding the channel, and a second LUT specifies linear combinations of the pseudo random sequences in the first LUT that produce channel codes to produce the digital sample points. Also included is using GPUs to generate the channel code for a point by mapping the channel code and time position, combining the code with data to be encoded, repeatedly applying the using and combining to produce points, using multiple GPU cores to encode sample points concurrently in the cycle, and sending an ordered sequence of points to a converter.

Abstract: An apparatus for locating an object of interest using offset. The object may be a mobile platform, or portion of same, associated with a vehicle, or a pavement segment or feature of or on a pavement segment on which the mobile platform is located. The vehicle includes first and second fixed points having a known offset from each other. An image sensor whose field of view includes the second fixed point and a segment of the pavement surface provides image data which is used with the known offset to calculate the precise location of the object of interest.

Abstract: A method of verifying a device location includes receiving a provisional location for a first device, setting a baseline location confidence value for the provisional location, determining a first network environment of the first device, and receiving one or more location reports each including a location for another device in the first network environment. For each received location report, the location in the location report is compared with the provisional location of the first device and a distance is calculated; and an adjustment to the location confidence value of the first device is calculated based on the calculated distance. An output location confidence value is generated for the provisional location of the first device based on the baseline location confidence value and the adjustment calculated for each received location report.

Abstract: A method and apparatus for measuring the angle of arrival AOA of Wi-Fi packets, using a switched beam antenna SBA is described. Wide antenna beams, quadrants, are selected in turn and a burst of packets is transmitted on each quadrant. The quadrant with the highest average signals strength is selected. Then the narrow antenna beams that make up that selected quadrant are selected, in sequence, and the average signal strength for each narrow beam is recorded. The narrow beam with the highest average signal strength is returned as the AOA. Based upon which narrow beam recorded the highest signal strength, the next sequence of antenna beams is selected. When the SBA is mounted on a mobile platform, the parameters of the transmission bursts are chosen such that the angular error due to cornering of the platform is negligible.

Abstract: Adjustable bearing supports for single-axis trackers supported by truss foundations. A two-piece assembly joins a pair of adjacent truss legs to form a rigid foundation while providing a movable support for a tracker bearing housing assembly or other structure. The movable support may slide in-plane, or alternatively, enable the bearing housing assembly to slide and rotate with respect to the truss cap structure joining the adjacent truss legs.

Abstract: Methods performed by wireless devices and base stations for performing GNSS-assisted measurement reporting are disclosed. A method performed by a wireless device includes: determining that a measurement reporting triggering condition has been satisfied based on at least a location of the wireless device, the location of the wireless device being determined using GNSS location measurements; determining one or more measurement quantities relating to satellite(s) for each of the plurality of surrounding cells; and reporting at least a subset of the measurement quantities. A method performed by a base station includes: signalling to a wireless device a measurement report triggering condition, the measurement reporting triggering condition being based on at least a location of the wireless device, the location of the wireless device being determined using GNSS location measurements; and receiving a measurement report from the wireless device when the measurement reporting triggering condition is satisfied.

Abstract: A method for geolocating a receiver by measuring times of reception, by the receiver, of a plurality of geolocation signals originating from a plurality of emitters, the geolocation signals are emitted on multiple different wavelengths, at least one geolocation signal having a frequency less than 1 GHz.

Abstract: A method of determining a location of a measurement device includes determining, at a server: measurement times of first positioning signal measurements, of first positioning signals from first positioning signal sources and/or a subset of positioning signal sources of second positioning signal sources. The method includes sending at least one measurement command from the server to the measurement device to cause the measurement device to obtain the first positioning signal measurements in accordance with the measurement times and/or obtain second positioning signal measurements of second positioning signals sent from the subset of positioning signal sources. The method includes: receiving, at the server from the measurement device, measurement data corresponding to the first positioning signal measurements and/or the second positioning signal measurements; and determining, at the server, the location of the measurement device based on the measurement data.

Abstract: A method may include generating a receive timing error group (Rx TEG) based on a time delay of a receive (Rx) signal, wherein the time delay is a time measured from an arrival of the Rx signal at a Rx antenna to a time of the Rx signal being digitized and time-stamped at a baseband processor of a user equipment (UE), determining a timing error group (TEG) index corresponding to the generated Rx TEG, determining a positioning measurement associated with the Rx antenna used to generate the Rx TEG, and reporting the positioning measurement associated with the Rx TEG index.

Abstract: An RF position tracking system for wirelessly tracking the three-dimensional position of a tracked object. The tracked object has at least one mobile antenna and at least one inertial sensor. The system uses a plurality of base antennas which communicate with the mobile antenna using radio signals. The tracked object also incorporates the inertial sensor to improve position stability by allowing the system to compare position data from radio signals to data provided by the inertial sensor.

Abstract: Methods, systems, and apparatus, including computer programs encoded on a computer storage medium, for identifying, at a monitoring system, a location of a device panel, the device panel being configured to communicate with a position module of the monitoring system; obtaining, by the position module, location information for a plurality of anchor devices, each anchor device of the plurality of anchor devices being located within a predefined area of a property; determining, by the position module, a respective location of each anchor device within the predefined area based on analysis of the location information for the plurality of anchor devices; and determining, by the position module, a location for a sensor in the predefined area based on the respective location of at least one anchor device.

Abstract: A vehicular lamp fitting and the like capable of preventing the distance between a radar unit and the radar cover from changing are provided. A vehicular lamp fitting includes: a lamp housing; an outer lens attached to the lamp housing while covering an opening of the lamp housing, and forming a first space between the outer lens and the lamp housing; a lamp unit disposed in the first space; a radar housing; a radar cover attached to the radar housing while covering an opening of the radar housing, and forming a second space between the radar cover and the radar housing; a radar unit disposed in the second space; a first fixing part fixing the radar unit to the radar housing; and a second fixing part fixing the radar cover to the radar housing.

Abstract: Described herein are systems and methods for detecting microwave pulses. An example method may include identifying, by a first sensor, a first signal in an environment, the first signal including a signal in a microwave frequency range. The example method may also include determining first data associated with the first signal, the first data being associated with one or more parameters. The example method may also include determining that the first data exceeds a threshold. The example method may also include sending, based on the determination that the first data exceeds a threshold, an alert.

Abstract: A radar system includes a first radar chip having one or more receiving channels and a second radar chip having one or more receiving channels, wherein the receiving channels of the first and second radar chips each have an RF input port and are configured to provide, based on an RF input signal received at the RF input port, a corresponding digital baseband signal that is characterizable by at least one signal parameter. The radar system further includes a power divider configured to forward an RF signal to both a first receiving channel integrated in the first radar chip and to a second receiving channel integrated in the second radar chip. A processor is configured to determine information indicating a deviation between the signal parameter of the digital baseband signal of the first receiving channel and the corresponding signal parameter of the digital baseband signal of the second receiving channel.

Abstract: A frequency modulated continuous wave (FMCW) radar system is provided that includes a receiver configured to generate a digital intermediate frequency (IF) signal, and an interference monitoring component coupled to the receiver to receive the digital IF signal, in which the interference monitoring component is configured to monitor at least one sub-band in the digital IF signal for interference, in which the at least one sub-band does not include a radar signal.

Abstract: A radar sensor includes a memory storing a model defining a relationship between a condition of the radar sensor and a plurality of features of radar detections, the model being generated by a machine learning approach and storing values of the plurality of features associated with the known states of the condition of the radar sensor. A radar detector transmits radar signals into a region, detects reflected returning radar signals from the region, and converts the reflected returning radar signals into digital data signals. A processor receives the digital data signals and processes the digital data signals to generate actual radar detections, each characterized by a plurality of the features of radar detections. The processor applies values of the features of the actual radar detections to the model to determine the state of the condition of the radar sensor.

Abstract: A device includes an input interface for receiving a target list for the MIMO radar sensor containing angular data including information regarding a target angle, at which the target is located, and channel data including information regarding reflection signals received from the target in individual channels in the MIMO radar sensor; a modeling unit for generating model data for each of the targets; a processor for determining a model error for each of the targets, containing information regarding a discrepancy between the channel data and the model data for the target; a selector for selecting one of the targets on the basis of the model error; and an adjustment unit for determining calibration coefficients for adjusting the channel outputs in the MIMO radar that compensate for the discrepancies between the channel data and the model data.

Abstract: A radar apparatus includes a radar transmission circuit that transmits a radar signal from a transmission array antenna, and a radar reception circuit that receives, from a reception array antenna, a reflected wave signal that is the radar signal reflected at a target. One of the transmission array antenna and the reception array antenna includes a first antenna element group having m antenna elements arranged at a first interval Dt along a first axis direction, wherein m is an integer of 2 or larger. The other one of the transmission array antenna and the reception array antenna includes a second antenna element group having n antenna elements arranged at a second interval Dr along the first axis direction, wherein n is an integer of 4 or larger. The second interval Dr includes several different intervals.

Abstract: A method for classifying objects based on measured data recorded by at least one radar sensor. In the method, a frequency spectrum of time-dependent measured data of the radar sensor is provided; from this frequency spectrum, locations from which reflected radar radiation has reached the radar sensor are ascertained; at least one group of such locations belonging to one and the same object is ascertained; for each location in this group, a portion of the frequency spectrum that corresponds to the radar radiation reflected from this location is ascertained; all these portions for the object are aggregated and are fed to a classifier; the object is assigned by the classifier to one or multiple classes of a predefined classification.

Abstract: Example embodiments relate to techniques for detecting adverse road conditions using radar. A computing device may generate a first radar representation that represents a field of view for a radar unit coupled to a vehicle and during clear weather conditions and store the first radar representation in memory. The computing device may receive radar data from the radar unit during navigation of the vehicle on a road and determine a second radar representation based on the radar data. The computing device may also perform a comparison between the first radar representation and the second radar representation and determine a road condition for the road based on the comparison. The road condition may represent a quantity of precipitation located on the road and provide control instructions to the vehicle based on the road condition for the road.

Abstract: Methods, apparatus and systems for monitoring an object expression are described. In one example, a described apparatus in a venue comprises a receiver and a processor. The receiver is configured for: receiving a wireless signal from a transmitter through a wireless multipath channel that is impacted by an expression of an object in the venue, wherein the object has at least one movable part and is expressed in the expression with respect to a setup in the venue; and obtaining a time series of channel information (TSCI) of the wireless multipath channel based on the wireless signal received by the receiver. The processor is configured for computing information associated with the object based at least partially on the TSCI obtained when the object is expressed in the expression, and performing, based on the information associated with the object, a task associated with at least one of the object and the venue.

Abstract: An optoelectronic sensor for detecting an object in a monitored zone having at least one light source for transmitting transmitted light, a light receiver having a reception optics arranged upstream for generating received signals from light beams remitted at the object, and a control and evaluation unit for acquiring information on the object from the received signals has a beam splitter arrangement arranged downstream of the light source for splitting the transmitted light into a plurality of transmitted light beams separated from one another, wherein the beam splitter arrangement includes a plurality of switchable beam splitters for splitting the transmitted light.

Abstract: Optical systems and methods for object detection and location. One example of an optical system includes a laser radar optical source positioned to emit a pulsed laser beam, a MEMS MMA positioned to scan the beam in a linear scan over a first area of a scene, a laser radar detector positioned to receive and integrate a reflection of the beam, a read-out integrated circuit (ROIC) configured to provide a first read-out signal based on the integrated reflection, and a controller configured to receive the first read-out signal, determine a range to the first area based on a time of flight of the pulsed laser beam, and identify a presence of an object within the scene based on a signal level of the first read-out signal, the first signal level corresponding to a reflectivity of a portion of the object within the first area of the scene.

Abstract: In one embodiment, a lidar system includes a light source configured to emit pulses of light. The emitted pulses of light include one or more series of standard-resolution pulses alternating with one or more series of high-resolution pulses. Each series of the standard-resolution pulses includes multiple pulses having a standard pulse period, and each series of the high-resolution pulses includes multiple pulses having a high-resolution pulse period. The standard pulse period is greater than or equal to a round-trip time associated with a maximum range of the lidar system, and the high-resolution pulse period is less than the standard pulse period. The lidar system also includes a scanner configured to scan at least a portion of the emitted pulses of light across a field of regard.

Abstract: A beam-steering engine, comprising an optical element switchable between a first operational mode and a second operational mode, in the first operational mode of the optical element the beam-steering engine is configured to output an input light beam incident on the beam-steering engine along a first propagation direction and in the second operational mode of the optical element the beam-steering engine is configured to output the input light beam incident on the beam-steering engine along a second propagation direction. A transition of the optical element between the first and second operational modes is characterized by a transition time period that varies with a temperature of the optical element. The beam-steering engine further includes a device to control a temperature of the solid-state optical element to maintain the transition time period below a certain limit.

Abstract: A LIDAR system has multiple optical components. At least one of the optical components is configured to output a LIDAR output signal that travels away from the LIDAR system and can be reflected by an object located outside of the LIDAR system. The LIDAR system also includes electronics configured to operate one or more of the optical components so as to tune the frequency of the LIDAR output signal without changing an amplitude of the LIDAR output signal.

Abstract: Example embodiments relate to calibration and localization of a light detection and ranging (lidar) device using a previously calibrated and localized lidar device. An example embodiment includes a method. The method includes receiving, by a computing device associated with a second vehicle, a first point cloud captured by a first lidar device of a first vehicle. The first point cloud includes points representing the second vehicle. The method also includes receiving, by the computing device, pose information indicative of a pose of the first vehicle. In addition, the method includes capturing, using a second lidar device of the second vehicle, a second point cloud. Further, the method includes receiving, by the computing device, a third point cloud representing the first vehicle. Yet further, the method includes calibrating and localizing, by the computing device, the second lidar device.

Abstract: Real-time monitoring of surroundings of a marine vessel. One or more observation sensor modules are configured and positioned to generate sensor data extending around the marine vessel. One or more data processors are configured to map and visualize the sensor data in relation to a virtual model of the marine vessel. A user interface is configured to display the virtual model together with the visualized sensor data from a user selectable point of view to a mariner of the marine vessel.

Abstract: A photodetection device includes a substrate and a plurality of pixel units. The plurality of pixel units includes a pixel unit including a first photodetector in an active area, and a pixel unit including a second photodetector in an inactive area. The first photodetector includes a first lower electrode layer, a first lower extrinsic semiconductor layer, a first intrinsic semiconductor layer, a first upper extrinsic semiconductor layer, and a first upper electrode layer. The second photodetector includes a second lower electrode layer, a second lower extrinsic semiconductor layer, a second intrinsic semiconductor layer, a second upper extrinsic semiconductor layer, and a second upper electrode layer. The second lower electrode layer is covered with the second lower extrinsic semiconductor layer and the second intrinsic semiconductor layer.

Abstract: A ray detector substrate has detection regions and includes a substrate, a first interdigital electrode and a second interdigital electrode disposed on a side of the substrate and located in each detection region, a first scintillator layer disposed on a side of the first interdigital electrode and the second interdigital electrode away from the substrate, and a second scintillator layer disposed on a side of first scintillator layer away from the substrate. The second scintillator layer is configured to convert part of rays incident onto the detection region into visible light, and transmit another part of the rays, so that the another part of the rays is incident onto the first scintillator layer through the second scintillator layer. The first scintillator layer is configured to convert the visible light converted by the second scintillator layer and the another part of the rays through the second scintillator layer into photocurrent.

Abstract: A signal detection device including: detection equipment including a photoelectric conversion element configured to convert a photon as a detection target into a current signal, and a current-voltage converter configured to convert the current signal into a voltage signal; a transmission unit configured to transmit the voltage signal; and a data collection unit configured to detect and collect the transmitted voltage signal. Here, the detection equipment is disposed inside a first shield case connected to a frame ground. The current-voltage converter includes a differential amplifier having first and second input terminals, the first input terminal is connected to a first output terminal of the photoelectric conversion element via a first input resistor, the second input terminal is connected to a second output terminal of the photoelectric conversion element and a ground via a second input resistor having a resistance value larger than that of the first input resistor.

Abstract: A method detects seismic events, in particular detects foreshocks for earthquake prediction. The events are detected by a plurality of sensors, wherein at least a part of a water pipe network on which the sensors are arranged is used for detection. An ultrasonic water meter to be connected to a water pipe network and an ultrasonic water meter system connected to a water pipe network are provided to detect seismic events.

Abstract: A method for automatically propagating a voltage along a marine seismic streamer, the method including detecting, at an ith concentrator of the streamer, a first voltage applied at a first high-voltage rail HV1; detecting, at the ith concentrator of the streamer, a second voltage applied at a second high-voltage rail HV2, the first and second high-voltage rails extend over the entire streamer; checking a predetermined condition at a first local controller of the ith concentrator; and closing a first switch SW1, which propagates the first high-voltage rail HV1, when the predetermined condition is satisfied.