Abstract: A radar system includes a transmitter circuit, which transmits a radar wave having a chirp frequency gradually increasing or decreasing to a target, and a frequency conversion circuit, which demodulates a signal of the radar wave reflected at the target by frequency-conversion in correspondence to the chirp frequency. A radar signal processor includes a variable amplifier connected to an output side of the frequency conversion circuit, and a feedback circuit which detects an output of the variable amplifier as a detection signal and feeds back a signal of a frequency band included in the detection signal to an input of the variable amplifier. The feedback circuit is configured to cut off and not cut off a frequency band including a DC offset transient response frequency, which occurs at time of frequency conversion by the frequency conversion circuit, during a specified period and a period other than the specified period, respectively.

Abstract: A semiconductor chip comprising at least one transmit channel and/or at least one receive channel for radar signals and also a sequencing circuit is proposed. In this case, the sequencing circuit is configured centrally to determine a sequencing scheme for time-dependent functions of the transmit channel and/or of the receive channel and to drive circuit elements of the transmit channel and/or of the receive channel in accordance with the sequencing scheme.

Abstract: A radar signal processing device capable of performing a highly accurate object identification is obtained. A first feature quantity related to a relative distance and a relative speed to an object, the direction and the reflection intensity of the object, which are extracted by a first feature quantity extraction block, is made identical in time series in a data storage processing block; a second feature quantity is extracted by a second feature quantity extraction block; one in which an instant score is accumulated in a cycle direction to the distribution of the second feature quantity related to a predetermined category calculated by an attribution degree calculation block is calculated as an accumulation score by an accumulation/instant score calculation block; and a category of the object is determined by an object determination block on the basis of the accumulation score calculated by the accumulation/instant score calculation block.

Abstract: A vehicle radar system, such as a multiple input multiple output (MIMO) radar system, for estimating a Doppler frequency shift and a method of using the same. In one example, a modulated signal is mixed with an orthogonal code sequence and is transmitted by a transmit antenna array with a plurality of transmitting antennas. The signals reflect off of a target object and are received by a receive antenna array with a plurality of receiving antennas. Each of the received signals, which likely includes a Doppler frequency shift, is processed and mixed with a number of frequency shift hypotheses that are intended to offset the Doppler frequency shift and result in a series of correlation values. The frequency shift hypothesis with the highest correlation value is selected and used to correct for the Doppler frequency shift so that more accurate target object parameters, such as velocity, can be obtained.

Abstract: A LIDAR 1 includes: a scanner 55 that emits outgoing light Lo while changing the outgoing direction thereof; a reflection member 8 that is arranged in a first outgoing direction and reflects the outgoing light Lo; an absorption member 7 that is arranged in a second outgoing direction and absorbs the outgoing light Lo; an APD 41 that receives return light Lr; and a DSP16. The DSP 16 generates replica u representing a component reflected by the absorption member 7 on the basis of output signals of the APD 41 obtained at each time when the outgoing light Lo is emitted in the first outgoing direction and in the second outgoing direction.

Abstract: An adjustable support structure for a projection system comprises a mounting base and a bracket assembly having a ring assembly rotationally secured to the mounting base and operative to rotate about a first axis. There is a platform bracket, pivotally secured to the ring assembly and operative to pivot about a second axis. The second axis is displaced from the first axis. There are a plurality of locking mechanisms. Each of the locking mechanisms is operative to lock the bracket assembly about a respective one of the axes.

Abstract: An enclosure, includes a housing and a window. The housing is configured to retain a LIDAR-sensor. The window is attached to the housing within an opening defined by the housing. The window is configured to transmit light from the LIDAR-sensor. The window is comprised of a silicone-based polymeric material having a thickness of at least three millimeters. The window is characterized as having a transmittance of at least 80% of the light at a wavelength of 1550 nanometers.

Abstract: An optical signal transmitter configured to emit wavelength-distinct optical signals along distinct directions to provide a field scanning effect without requiring moving parts to effectuate the scanning In one implementation, the optical signal transmitter includes a laser source for generating an optical signal including a set of distinct wavelengths, an optical amplifier configured to amplify the optical signal, a wavelength splitter configured to generate a set of optical signals consisting of distinct wavelengths, respectively, and a set of emission ports for emitting the set of optical signals in different directions. In another implementation, the wavelength splitting occurs at the set of emission ports. In yet another implementation, two stages of wavelength splitting are provided. The optical signal transmitter may be implemented in a LIDAR system for ascertaining information concerning objects-of-interests.

Abstract: A system includes a first lidar sensor and a second lidar sensor, where each lidar sensor includes a scanner configured to direct a set of pulses of light along a scan pattern and a receiver configured to detect scattered light from the set of light pulses. The scan patterns are at least partially overlapped in an overlap region. The system further includes an enclosure, where the first lidar sensor and the second lidar sensor are contained within the enclosure. Each scanner includes one or more mirrors, and each mirror is driven by a scan mechanism.

Abstract: A method and system for targeting and tracking an intruder within a specified volume, which may include the following steps: periodically scanning through a defined zone of coverage with a laser beam produced by at least one laser transmitter, said defined zone of coverage being within said specified volume and adjustable by motion of at least one of a swing mirror or a rotating block; collecting, with at least one laser sensor, reflections of said laser beam reflected from objects within said adjustable defined zone of coverage; applying signal processing algorithms to LADAR signals to determine a presence of an intruder; calculating, in the event of a positive determination of intruder presence, respective orientation parameters of said intruder; and, moving said swing mirror or said rotating block, thereby adjusting said defined zone of coverage, to target said at least one laser transmitter and to track said intruder.

Abstract: Described herein are systems and methods that that mitigate avalanche photodiode (APD) blinding and allow for improved accuracy in the detection of a multi-return light signal. A blinding spot may occur due to saturation of a primary APD. The systems and methods include the incorporation of a redundant APD and the utilization of time diversity and space diversity. Detection by the APDs is activated by a bias signal. The redundant APD receives a time delayed bias signal compared to the primary APD. Additionally, the redundant APD is positioned off the main focal plane in order to attenuate an output of the redundant APD. With attenuation, the redundant APD may not saturate and may have a successful detection during the blinding spot of the primary APD. Embodiments may include multiple primary APDs and multiple secondary APDs.

Abstract: A Light Detection And Ranging (LIDAR) apparatus includes a pulsed light source to emit optical signals, a detector array comprising single-photon detectors to output respective detection signals indicating times of arrival of a plurality of photons incident thereon, and processing circuitry to receive the respective detection signals.

Abstract: For test/calibration of an electro-optic range-finding device, one or more fiber bundles each are selected to have a length corresponding to predetermined time-of-flight for light pulses. An input end is positioned proximate to the laser aperture of the range-finding device to receive a portion of light emitted through the laser aperture, and the output end is positioned to emit light from the respective fiber bundle through the detector aperture of the range-finding device. A fiber attenuator is connected along each fiber of the one or more fiber bundles to attenuate an amplitude of light propagating through the respective fiber by an amount corresponding to a target of known reflectance and distance. The one or more fiber bundles are each coiled to reduce a linear distance over which the one or more fiber bundles extend. The one or more fiber bundles may each comprise a plurality of fibers.

Abstract: A system includes a plurality of photodiode sensors spaced from one another and mounted to a reflective surface, a transparent layer spaced from and substantially parallel to the reflective surface, and a plurality of photodiode transmitters at least one of mounted to the reflective surface and disposed between the reflective surface and the transparent layer.

Abstract: An electronic device including a sound receiver and a processor is provided. The sound receiver receives a sound signal provided by a sound generator. When the processor determines that an obstacle is blocked between the electronic device and the fixed device, the processor estimates a virtual position of the electronic device at a current time according to previous movement information and a previous position of the electronic device. The virtual position has a shortest path between a boundary position of the obstacle and the sound generator. The processor obtains a first relative distance between the electronic device and the boundary position according to the sound signal received by the sound receiver and the boundary position. The processor calculates a relative velocity and a relative acceleration of the electronic device relative to the fixed device at the current time according to the sound signal and the first relative distance.

Abstract: Radio frequency device, system comprising radio frequency device, and corresponding methods. Radio Frequency devices are provided where a radio frequency circuit may be selectively coupled to a radar circuit or a communication circuit.

Abstract: Methods are described for the determination of a boundary of a space of interest using a radar sensor. In one aspect, a radar sensor scans and tracks all moving targets within the field of view and derives information relating to the tracked moving targets, such as, positional information and velocity information. From the positional and velocity information, regions which are not traversed by the tracked moving targets correspond to “no-go” regions. These “no-go” regions are used to derive a model for the space of interest which includes a boundary for the space of interest. The derived model is continuously updated due to the continuous detecting and tracking of moving targets within the field of view of the radar sensor. The detecting and tracking of moving targets can also be used to refine models of spaces of interest determined by another method.

Abstract: An off-road dump truck includes a vehicle body, a peripheral recognition device, and an obstacle discrimination device. The peripheral recognition device detects obstacle candidates in front of the vehicle body. The obstacle discrimination device classifies the obstacle candidates, which were detected by the peripheral recognition device, into obstacles and non-obstacles and outputs, as obstacles, the obstacle candidates classified as obstacles. The obstacle discrimination device includes a travel state determination section, a distance filter section, and a reflection intensity filter section. The travel state determination section determines whether each obstacle candidate is a moving object or a stationary object. The distance filter section compares a distance, where the stationary object was first detected, with a distance threshold.

Abstract: A method of operating a radar sensor system includes: frequency down-converting a reception signal that is chirp-modulated with a sequence of chirp ramps to an intermediate frequency signal; and high-pass filtering the intermediate frequency signal to produce a high-pass filtered signal. High-pass filtering includes: first high-pass filtering, with a first corner frequency, the intermediate frequency signal at each chirp in the chirp modulation of the reception signal; and replacing the first high-pass filtering with a second high-pass filtering with a second corner frequency, the first corner frequency being higher than the second corner frequency.

Abstract: The disclosure provides an example of a system including a radio frequency (RF) wireless communication network (network) including a plurality of nodes in an area and a computer coupled to the network. Each of the nodes includes a transmitter and a receiver. At plurality of times, each transmitter transmits RF spectrum signals (signals) and each receiver receives the signals and also generates an indicator data of a signal characteristic of the received signal propagated in the network. When each time among the plurality of times is a current time, the computer obtains the indicator data of the signal, determines a modification in the indicator data at the current time from the indicator data at a preceding time due to a movement of an occupant in the area and detect an occupancy condition in the area based on the modification in the indicator data and a parameter of a configuration of the network.

Abstract: Method for determining a staggered pattern and interrogation mode pattern of an Secondary Surveillance Radar (SSR) is disclosed. The method enables a Passive SSR (PSSR) to work not only inside but also outside the SSR beam. When PSSR is in the wider beam of the SSR, multiple P2-pulses are detected as time-ordered sequence of P2-pulse intervals, from which a repeating sequence and further a stagger pattern is determined. The interrogation mode pattern is determined by comparing the staggered pattern with the interrogation signals. A transmit time of the P3-pulse is predicted based on the staggered pattern and the interrogation mode pattern. Corresponding system is also provided.

Abstract: In accordance with a first aspect of the present disclosure, a transponder is provided, comprising: a frequency detector configured to monitor an output frequency of a clock-stop sensor of said transponder, wherein said frequency detector is further configured to determine if said output frequency falls within a response detection frequency range of an external reader, and a frequency shifter configured to shift, in response to the frequency detector determining that the output frequency falls within said response detection frequency range, said output frequency to a value outside said response detection frequency range. In accordance with a second aspect of the present disclosure, a corresponding method of operating a transponder is conceived. In accordance with a third aspect of the present disclosure, a corresponding computer program is provided.

Abstract: A system and method of enhancing radar functionality in a geographical region. In one or more terminal radar systems, the existing radar transmitter is upgraded with an improved transmitter having a higher efficiency, the existing radar receiver is upgraded with an improved receiver having a higher sensitivity, and the existing processor with is improved or modified to perform new functions including the acquisition of additional surveillance data, extended surveillance range and improved target resolution. The new functionality enables the selected terminal to provide long range, 3-D en route radar data, including height information, while continuing to provide short-range, 2-D surveillance data.

Abstract: A radar sensing system for a vehicle includes a radar sensor disposed at the vehicle so as to have a field of sensing exterior of the vehicle. The radar sensor includes a plurality of transmitters that transmit radio signals and a plurality of receivers that receive radio signals. The received radio signals are transmitted radio signals that are reflected from an object. A control has a processor for processing outputs of the receivers. The transmitted radio signals reflect off a radar reflective object, which includes one of radar reflective road markings or radar reflective signs. The control, via processing of outputs of the receivers by the processor, determines information pertaining to the radar reflective object based on the reflected radio signals.

Abstract: A distance measuring apparatus includes a light source to emit light beams, an optical scanner to scan the light beams output from the light source over a predetermined range, a light receiver to receive reflected light obtained as a result of the light beams being reflected by a target object, and to output detection signals, and a control circuit to measure a distance to the target object based on the detection signals. The light source including a plurality of light-emitting device groups that are arranged in a scan direction of a scan performed by the optical scanner, and the control circuit being to make the plurality of light-emitting device groups emit light at respective different timings in a single scan, and to measure the distance to the target object based on a sum of the detection signals.

Abstract: A three-dimensional (3D) coordinate measurement device combines tracker and scanner functionality. The tracker function is configured to send light to a retroreflector and determine distance to the retroreflector based on the reflected light. The tracker is also configured to track the retroreflector as it moves, and to determine 3D coordinates of the retroreflector. The scanner is configured to send a beam of light to a point on an object surface and to determine 3D coordinate of the point. In addition, the scanner is configured to adjustably focus the beam of light.

Abstract: A method for recognizing an object located in an object space includes emitting a distance measuring pulse into the object space by a signal time-of-flight based distance measuring unit. The object is provided with a marker which, in response to the influence of the distance measuring pulse, emits electromagnetic marker radiation in which object information for the object recognition is stored. The method further includes recording the marker radiation by an electrical radiation detector and the object information for object recognition being assigned to the object.

Abstract: A scanning rangefinding system includes a MEMS device with a scanning mirror that sweeps a beam in two dimensions. Actuating circuits receive angular extents and offset information and provide signal stimulus to the MEMS device to control the amount and direction of mirror deflection on two axes. The scan angle and offset information may be modified to create a repeating pattern of different fields of view.

Abstract: A laser radar apparatus in the present disclosure includes: a scanner 60 capable of beam scanning at a first angular speed; a measurable wind distance calculator monitor 30 to calculate and to monitor a measurable wind distance based on wind measurement data obtained through beam scanning by the scanner; an optical axis angular correction amount deriver 40 to derive an optical axis angular correction amount being able to obtain the largest distance of the measurable wind distance, based on a first angular speed and the wind measurement data obtained through beam scanning at a second angular speed lower than the first angular speed, when decrease of the measurable wind distance is detected by the measurable wind distance calculator monitor; and an optical axis corrector 8 to correct an optical axis angular deviation between transmitted light and reception light, based on the optical axis angular correction amount.

Abstract: A system for indoor localization using satellite navigation signals in a Distributed Antenna System includes a plurality of Off-Air Access Units (OAAUs). Each of the plurality of OAAUs is operable to receive an individual satellite navigation signal from at least one of a plurality of satellites and operable to route signals optically to one or more DAUs. The system also includes a plurality of remote DRUs located at a Remote location. The plurality of remote DRUs are operable to receive signals from a plurality of the one or more DAUs. The system further includes an algorithm to delay each individual satellite navigation signal for providing indoor localization at each of the plurality of DRUs.

Abstract: A method for providing raw correction data for correcting atmospheric disturbances for satellite navigation includes checking whether a mobile satellite receiver for satellite navigation is in an immobile state using at least one sensor signal. The sensor signal represents a measurement variable dependent on a state of movement of the mobile satellite receiver. The method further includes evaluating at least one satellite signal transmitted between at least one satellite and the mobile satellite receiver in the immobile state with regard to a signal property dependent on atmospheric disturbances in order to generate the raw correction data. The raw correction data represents an item of information regarding the atmospheric disturbances.

Abstract: In a positioning augmentation device (40), a plan making unit (84) selects a subset satisfying selection conditions from within a candidate set that is a set of satellites being selection candidates and saves plan data (43) indicating the selected subset in a memory (72). A plan alteration unit (85) acquires integrity information indicating quality of a positioning signal transmitted from each satellite and detects a satellite of which the quality of the positioning signal does not satisfy quality conditions, from within the subset selected by the plan making unit (84), based on the acquired integrity information. The plan alteration unit (85) replaces the detected satellite in the subset with another satellite included in the candidate set.

Abstract: A method for providing integrity information for checking atmospheric correction parameters for the correction of atmospheric disturbances for satellite navigation for a vehicle includes reading state signals relating to a state of an atmosphere between at least one satellite receiver and at least one satellite of the at least one satellite receiver. Each state signal represents certain state data that are transmitted between a satellite and a satellite receiver. The method further includes using at least one satellite signal and that are dependent on a state of the atmosphere between the satellite and the satellite receiver. The method further includes determining the integrity information using the state data. A variation of the state data against time is analyzed.

Abstract: A method of providing accurate position, navigation, and timing information comprising the steps of providing at least four transceiver devices, providing an auxiliary GPS device, and providing a receiver GPS device. Each transceiver devices receives a plurality of GPS signals from a plurality of GPS satellites, and calculates a transceiver position and transceiver velocity vector. The transceiver position, transceiver velocity vector, and GPS signal are repackaged at each transceiver into a first spread signal structure, which is transmitted from each transceiver as a first GPS-like signal. The GPS-like signal is received at an auxiliary GPS device, which generates a simulated GPS signal. This simulated GPS signal is then output and received by a simulated GPS device.

Abstract: A tunnel detection system for a motor vehicle comprises a radiofrequency signal receiver provided to receive a radiofrequency signal coming from a source external to the vehicle; a controller communicating with the radiofrequency signal receiver, the controller being configured to detect at least one amplitude variation in the radiofrequency signal received by the receiver; the controller is configured to determine at least one correspondence level representative of the difference between the detected amplitude variation in the radiofrequency signal and at least one predetermined reference signal amplitude variation representative of the amplitude variation in a signal received by the receiver when the receiver travels into a tunnel; the controller is configured to compare the determined correspondence level with a predetermined minimum correspondence threshold, and detect the tunnel being travelled through by the detection system when the determined correspondence level is greater than or equal to the predet

Abstract: A satellite signal receiving circuit includes an oscillator, two mixers, two phase shifters, two low-pass filters, two phase operation circuits, and a bandpass filter. When the frequency of the oscillator is between the center frequencies of the Global Orbiting Navigation Satellite System (GLONASS) and the GPS or the Galileo system, the GLONASS and GPS/Galileo satellite baseband signals are obtained through phase addition and subtraction performed by the phase operation circuits, while the BeiDou Navigation Satellite System (BDS) baseband signal is obtained through the bandpass filter. When the frequency of the oscillator is between the center frequencies of the BDS and the GPS or the Galileo system, the BDS and GPS/Galileo satellite baseband signals are obtained through phase addition and subtraction performed by the phase operation circuits, while the GLONASS satellite baseband signal is obtained through the bandpass filter.

Abstract: A satellite signal receiving device includes a signal analyzing device and a processor; the signal analyzing device processes a received satellite signal to obtain first information, ands send the first information to the processor; the processor receives a security command and the first information and determines an information processing type for the received first information based on the security command; determines information to process in the first information when it is determined that the information processing type of the first information is the first processing type; sends the information to process and the security command to a security algorithm device, and obtains second information returned after the security algorithm device processed the first information based on the security command; and transmits the second information.

Abstract: Systems, computer-implemented methods, apparatus and/or computer program products are provided that facilitate improving the accuracy of global positioning system (GPS) coordinates of indoor photos. The disclosed subject matter further provides systems, computer-implemented methods, apparatus and/or computer program products that facilitate generating exterior photos of structures based on GPS coordinates of indoor photos.

Abstract: A radiation imaging apparatus is provided. The apparatus comprises pixels configured to detect radiation with a first sensitivity and a second sensitivity lower than the first sensitivity. Each of the pixels starts an operation for accumulating a signal with the first sensitivity in accordance with a start of irradiation of the radiation imaging apparatus with radiation, samples an accumulated signal as a first signal after lapse of a first time shorter than a period of irradiation with radiation since a start of an operation for accumulating a signal, switches to the second sensitivity, and accumulates a signal, samples an accumulated signal as a second signal in accordance with an end of irradiation of the radiation imaging apparatus with radiation, and outputs the first signal and the second signal to generate a radiation image based on the first signal and the second signal.

Abstract: An imaging detector is provided that includes a continuous NaI crystal, a glass plate, an array of SiPMs, and an array of concentrators. The continuous NaI crystal defines a reception side and a detection side. The glass plate is disposed on the detection side of the continuous NaI crystal, and is interposed between the detection side of the continuous NaI crystal and the array. The array of concentrators corresponds to the array of SiPMs, and is interposed between the array of SiPMs and the glass plate. Each concentrator has a reception side opening that is larger than a detection side opening, with the detection side opening disposed proximate to a corresponding SiPM.

Abstract: Codoped alkali and alkaline earth halide scintillators are described. More particularly, the scintillators are codoped with tetravalent ions, such as Ti4+, Zr4+, Hf4+, Ge4+. The codoping can alter one or more optical and/or scintillation property of the scintillator material. For example, the codoping can improve energy resolution. Radiation detectors comprising the scintillators and methods of detecting high energy radiation using the radiation detectors are also described.

Abstract: The present disclosure relates to a system for PET imaging. The system may include a first device and a second device. The first device may include a first scanning channel. The second device may include a second scanning channel connected to the first scanning channel, a heat generating component, and a cooling assembly configured to cool the heat generating component, wherein the cooling assembly may include an inlet chamber and a return chamber, the heat generating component may be closer to a first side of the second device than at least one of the inlet chamber or the return chamber, and the first side of the second device may face the first device.

Abstract: Provided is a device for spectrometry of a radiation of photons, including a detector configured to receive the radiation and to deliver, at an output, an electrical signal that is a function of the radiation (X) received, a reference database that can be parameterised by means of a first parameter, a comparator configured to establish a comparison between the electrical signal and the reference signal, the comparator delivering a signal (E(t)) representative of the energy of each photon of the radiation and a quality factor (B(t)) of the comparison, and a feedback loop enabling the first parameter of the reference database to be adapted so as to optimise the quality factor (B(t)).

Abstract: A vehicle adapted for seismic survey operations includes a hybrid engine, which has an internal combustion mode and an electrical power mode. The engine operating mode is selected based on the activity in which the vehicle is engaging. During movement, the internal combustion mode may be used and during seismic sweeping, the electrical power mode may be used. In variants, the electrical power may be used during movement.

Abstract: A seismic sensor assembly can include a housing that defines a longitudinal axis; a sensor; sensor circuitry operatively coupled to the sensor; and overvoltage protection circuitry electrically coupled to the housing.

Abstract: A method and system are provided for acquiring the probability of slope failure and destabilization caused by an earthquake. For example, the method includes performing azimuth division in an area around a site at which a slope is located as a center, pre-setting a seismic acceleration threshold value that varies within a certain range, and calculating an exceeding probability that the seismic acceleration of the slope site generated by an earthquake in each azimuth domain is greater than or equal to the seismic acceleration threshold value, to establish an exceeding probability curve of site seismic acceleration corresponding to each azimuth domain. The method and system achieve estimation of the probability of slope destabilization caused by an earthquake by comprehensively considering the uncertainty of the seismic action and the uncertainty of slope failure and destabilization.

Abstract: The invention provides a method of detecting a seismic event, which comprises acquiring (110) a digital signal x characteristic of a signal measured by at least one seismic sensor, and calculating (130) a time-frequency distribution for at least one section of a given duration of said signal, in a given frequency band. For each frequency of said frequency band, the calculated time-frequency distribution is normalized. The method also comprises calculating (150) the moving average of the normalized time-frequency distribution ZD, in said frequency band and in a time window, given reference L, centered on the time n; and detecting (160) a seismic event when the average exceeds a predefined threshold value. The invention also provides a corresponding detection system.

Abstract: Prediction and subtraction of multiple diffractions may include transforming previously acquired seismic data from a time-space domain to a transformed domain using a dictionary of compressive basis functions and separating, within the transformed previously acquired seismic data, a first portion and a second portion of the transformed previously acquired seismic data. Prediction and subtraction of multiple diffractions may also include predicting a plurality of multiple diffractions based on the separated first and second portions and adaptively subtracting the predicted multiple diffractions from the previously acquired seismic data. Prediction and subtraction of multiple diffractions may also include inverse transforming a particular seismic data set from the transformed domain to the time-space domain.

Abstract: A method is disclosed and includes receiving a seismic cube. The seismic cube includes a three-dimensional image of a portion of a subsurface area. The method further includes providing the seismic cube to a machine learning process. The machine learning process includes one or more neural networks used for predicting a location of a subsurface seismic layer in the received seismic cube. The method also includes receiving, from the machine learning process, the prediction of the location of the subsurface seismic layer in the seismic cube.

Abstract: Apparatus (10) and methods for measurement of pore pressure in rock formations through a metal borehole casing (32) after a well is cased and cemented, are described. Such measurements may be accomplished by using the Dynamic Acoustic Elasticity (DAE) method for characterizing nonlinear parameters by perturbing a selected rock formation region with a High Amplitude, Low Frequency (HALF) acoustic strain wave, and probing this region using a Low Amplitude, High Frequency (LAHF) acoustic wave (18), (22). Time reversal techniques (36) may be employed for focusing acoustic energy into the formation in the vicinity of the pipe or open hole. The change in wave speed of the probe pulses as the HALF induced strain wave oscillation propagates through the formation, as a function of the induced strain, may be used to determine the nonlinear elastic parameters ?, ?, ?, and A of the pore pressure, from which the pore pressure may be determined in the region of the HALF wave.