Abstract: A method of estimating the location of a signal source comprises, by a processing unit: determining ???m,n which represents a difference between accumulated phases of signals, Sm and Sn, received by at least one pair of the receivers, determining a first estimate of the location of said signal source based on position data and ???m,n of said at least one pair of receivers, said first estimate being associated with an accuracy area, determining data representative of difference in times of arrival of modulation patterns of the signals Sm, Sn, wherein said data comprise an ambiguity, and for said at least one pair of receivers, using at least said data representative of difference in times of arrival of the modulation patterns of the signals, ???m,n, and said accuracy area, to obtain second estimates êSrck of the source location, at least some of them being located within the accuracy area.

Abstract: An RF receiver may include antenna elements to receive RF signals, and electro-optic modulators to generate corresponding upconverted optical signals by mixing an RF signal with an optical carrier beam. The RF receiver may include a transmission array having a first bundle of optical waveguides that receive and transmit upconverted optical signals from their ends. The ends may be arranged in a first pattern. The RF receiver may include an interference space to receive the upconverted optical signals to form a composite beam, and an array of single mode optical fibers that have lenses positioned in a detection plane to receive a portion of the composite beam. The first pattern of the ends generates an RF emitter interference pattern at the detection plane, and the single mode optical fiber lenses have a geometric arrangement that corresponds to the first RF emitter interference pattern.

Abstract: A method for managing a communication channel used by a plurality of Wi-Fi devices of a Wi-Fi network of the backhaul type for implementing a backhaul network in said Wi-Fi network. A first Wi-Fi device in the plurality performs the method and comprises: detecting a disconnection from an initial channel used by the plurality of Wi-Fi devices for implementing the backhaul network of a second Wi-Fi device in the plurality connected directly to the first Wi-Fi device; listening on a backup channel, to which the second Wi-Fi device is able to migrate to implement the backhaul network in the event of detection, by the second Wi-Fi device, of a radar signal on the initial channel; causing the first Wi-Fi device to migrate to the backup channel in the event of reception on the backup channel by the first Wi-Fi device of a frame containing an identifier of the second device.

Abstract: The present disclosure provides an anti jamming system for a wireless communication system an antenna array comprising N antenna elements. At least two multiphase filters being connected to the antenna array and configured to receive an antenna element signal from each one of the N antenna elements. An anti-jamming system for a wireless communication system comprising an antenna array comprising N antenna elements and a filter configured to attenuate jamming signals from sources that is greater than, less than, or equal to N. An anti-jamming system for a wireless communication system comprising a multiphase filter connected to the antenna array to receive an antenna element signal from each antenna element of the antenna array, the multiphase filters comprising a first phase and a second phase, wherein the first phase of the multiphase filter executes a Frost's algorithm and the second phase of the multiphase filter executes a Maximin algorithm.

Abstract: A communications device includes a uniform linear array of M antennas and a field programmable gate array (FPGA) having pipelined stages in which execution of overlapping instructions estimate a direction of arrival of RF signals from multiple sources. A preprocessing stage of the FPGA includes at least one configurable logic block configured to apply forward/backward averaging spatial smoothing to a signal space matrix extracted from a covariance matrix in the preprocessing stage. The FPGA further includes at least one configurable logic block configured to compute the direction of arrival angle for the RF signals using a least squares method.

Abstract: A communications device includes a uniform linear array of M antennas and a field programmable gate array (FPGA) having pipelined stages in which execution of overlapping instructions estimate a direction of arrival of RF signals from multiple sources. A preprocessing stage of the FPGA includes at least one configurable logic block configured to apply forward/backward averaging spatial smoothing to a signal space matrix extracted from a covariance matrix in the preprocessing stage. The FPGA further includes at least one configurable logic block configured to compute the direction of arrival angle for the RF signals using a least squares method.

Abstract: Methods, devices, systems, media, and receivers for processing GNSS signals are described. One aspect of the present disclosure provides a method for processing satellite signals of a Global Navigation Satellite System (GNSS), the method comprising: receiving a first GNSS signal transmitted in a first GNSS operational band by a satellite of the GNSS and a second GNSS signal transmitted in a second GNSS operational band by the satellite; tracking the first GNSS signal; generating, from the tracking of the first GNSS signal, tracking parameters for the first GNSS signal; and decoding, at least based on the tracking parameters for the first GNSS signal, the second GNSS signal, wherein the first GNSS operational band is one of L1 band, L2 band or L5 band, and the second GNSS operational band is L6 band.

Abstract: A communications device includes a uniform linear array of M antennas and a field programmable gate array (FPGA) having pipelined stages in which execution of overlapping instructions estimate a direction of arrival of RF signals from multiple sources. A preprocessing stage of the FPGA includes at least one configurable logic block configured to apply forward/backward averaging spatial smoothing to a signal space matrix extracted from a covariance matrix in the preprocessing stage. The FPGA further includes at least one configurable logic block configured to compute the direction of arrival angle for the RF signals using a least squares method.

Abstract: A distance measuring apparatus according to an embodiment includes, a filter section configured to perform band limitation on a transmission signal and output the transmission signal, and to perform band limitation on a reception signal from an antenna section and output the reception signal, a distance measuring section configured to perform a distance measurement computation based on the transmission signal and the reception signal, and to obtain a delay of a signal passing through the filter section and perform calibration of the distance measurement computation, a signal interruption section configured to interrupt transmission of a signal between the filter section and the antenna section, and a control section configured to control the signal interruption section to interrupt the transmission of the signal during a period of the calibration.

Abstract: In one embodiment, a method includes receiving a plurality of radio frequency chains at a wireless device in a block based modulation environment, recording subcarrier phases and differences between the subcarrier phases, and using the subcarrier phase differences to construct a feature vector for use in angle of arrival calculated positioning of a mobile device.

Abstract: Presented herein are techniques for assigning Ultra-Wideband (UWB) anchors for client ranging. A location server can estimate a coarse location of a mobile device using a localization technique other than a UWB localization technique. The localization technique can involve multiple wireless access points or other radio devices. The location server can define an area around the coarse location to identify a set of candidate anchors for UWB ranging. The set of candidate anchors can be disposed within the area and include at least a subset of the radio devices. The location server can modify the set of candidate anchors to create a modified set of candidate anchors that includes only UWB-enabled devices. The location server can select a primary anchor from the modified set of candidate anchors and send a command to cause a UWB ranging procedure to be initiated between the primary anchor and the mobile device.

Abstract: An apparatus and digital signal processing means are disclosed to reliably and rapidly receive and detect navigation signals, e.g., Global Navigation Satellite System (GNSS) signals, such as Global Position System (GPS) L1 legacy, L1C, and L5 signals, using combinations of spatially diverse antenna arrays, polarization-diverse antenna arrays, frequency-channelized analysis filters, and perfect-reconstruction synthesis filters, by exploiting features of those signals that are self-coherent over known framing intervals. Among other advantages, the means can reliably and rapidly identify navigation signals based on those features, improve their quality ahead of, or during, signal despreading operations, and detect and excise inadvertent or targeted electronic attack (EA) measures, e.g., navigation signal spoofers, and narrowband or wideband jamming and co-channel interference.

Abstract: Systems, methods, and apparatus cause a first wireless device to transmit to a plurality of locator devices, an extended signal including a first segment and second segment. The first segment includes an indication for each of the plurality of locator devices to listen for a change in the extended signal from the first segment to the second segment. The second segment includes an indication for each of the plurality of locator devices to rotate through a plurality of antennas to receive the second segment via the plurality of antennas. Responsive to the transmitting of the extended signal, receiving direction data from each of the plurality of locator devices.

Abstract: FMCW radar sensor including multiple high-frequency modules, which are synchronized with one another by a synchronization signal. At least one includes a transmitting part for generating a frequency-modulated transmit signal. At least two high-frequency modules, physically separated from one another, each include a receiving part for receiving a radar echo, each receiving part being assigned a mixer, which generates an intermediate frequency signal by mixing the received signal with a portion of the transmit signal, and an evaluation unit. The evaluation unit is designed to record the intermediate frequency signal over a measuring period as a function of time, and to subject the time signal thus obtained to a Fourier transform. At least one of the evaluation units is designed to window the time signal before the Fourier transform using a complex-valued window function to compensate for a propagation time difference of the synchronization signal between the receiving parts.

Abstract: A communication signal demodulation apparatus demodulates a communication signal to generate an output signal. The communication signal demodulation apparatus includes: plural sensor circuits which sense different electrical characteristics of one same communication signal and generate corresponding sensing modulation signals respectively; plural processing filters which filter the corresponding sensing modulation signals respectively and generate corresponding filtered modulation signals respectively; plural demodulators which demodulate the plural filtered modulation signals and generate corresponding demodulation signals respectively, wherein each of the filtered modulation signals corresponds to at least one of the demodulators; and a determination circuit which receive the plural demodulation signals, determine whether each unit signal of each of the demodulation signals is correct or not according to a determination mechanism, and combine one or more correct unit signals to generate the output signal.

Abstract: An apparatus obtains a set of radio data comprising signal strength related values for radio signals transmitted by a transmitter with an association of each signal strength related value with a representation of a geographical location. The apparatus applies a frequency transform to the obtained set of radio data to obtain transform coefficients, each transform coefficient comprising a transform index and an associated transform value. The apparatus selects a subset of transform indices having more significant transform values than the remaining transform indices and compresses the transform indices by encoding each transform index exploiting a probability of occurrence of an index value of a respective transform index. The same or another apparatus decodes the compressed transform indices again for use in position operations.

Abstract: Systems, methods, and instrumentalities are disclosed for antenna virtualization, e.g., in at least a two-dimensional antenna array. NE physical antenna elements may be virtualized to Np logical antenna ports. A virtualization may be WTRU-specific, which may optimize MIMO performance. A simplified MIMO scheme may be used with A reduction in feedback, reference signal, and/or control signaling overhead. Antenna virtualization schemes may utilize channel characteristics. Antenna virtualization may be defined, for example, based on antenna port to antenna element mapping, based on a measurement reference signal, based on a codebook or a codebook subset or based on an antenna virtualization matrix. One or more antenna virtualization schemes may be configured in a cell. Antenna virtualization schemes may be configured in a WTRU-specific manner, perhaps for example based on a WTRU channel characteristic(s). A WTRU may report one or more useful (e.g., optimized) antenna virtualization schemes, e.g.

Abstract: An RF receiver may include antenna elements to receive RF signals, and electro-optic modulators to generate corresponding upconverted optical signals by mixing an RF signal with an optical carrier beam. The RF receiver may include a transmission array having a first bundle of optical waveguides that receive and transmit upconverted optical signals from their ends. The ends may be arranged in a first pattern. The RF receiver may include an interference space to receive the upconverted optical signals to form a composite beam, and an array of single mode optical fibers that have lenses positioned in a detection plane to receive a portion of the composite beam. The first pattern of the ends generates an RF emitter interference pattern at the detection plane, and the single mode optical fiber lenses have a geometric arrangement that corresponds to the first RF emitter interference pattern.

Abstract: An active electronically steerable receive antenna may comprise an antenna array that includes multiple receive antenna elements. Reflected radar signals may be received at the receive antenna elements, and received signals may be obtained from the receive antenna elements. The received signals may be processed via at least frequency down-conversion, analog-to-digital conversion, generation of digital signals, and alignment of the received signals or the digital signals for a predetermined angle of incidence. Multiple signals including a sum beamforming signal and a product beamforming may be multiplied to determine a beamformed signal. The sum beamforming signal and the product beamforming signal may be respectively determined by summing or multiplying at least two of the digital signals. The product beamforming signal may be a grating lobe suppression signal that suppresses grating lobes of the sum beamforming signal when multiplied with the sum beamforming signal.

Abstract: Described is a cognitive signal processor that is implemented in a field programmable gate array (FPGA). During operation, the FGPA receives a continuous noisy signal. The continuous noisy signal is a time-series of data points from a mixture signal of waveforms having both noise and a desired waveform signal. The continuous noisy signal is linearly mapped to reservoir states of a dynamical reservoir. A high-dimensional state-space representation of the continuous noisy signal is generated by digitally combining the continuous noisy signal with the reservoir states. Notably, the continuous noisy signal is approximated over a time interval based on a linear basis function. One or more delay-embedded state signals are then generated based on the reservoir states. The continuous noisy signal is then denoised by removing the noise from the desired waveform signal, resulting in a denoised waveform signal.

Abstract: A method and system is provided for finding and analyzing gait parameters and postural balance of a person using a Kinect system. The system is easy to use and can be installed at home as well as in clinic. The system includes a Kinect sensor, a software development kit (SDK) and a processor. The temporal skeleton information obtained from the Kinect sensor to evaluate gait parameters includes stride length, stride time, stance time and swing time. Eigenvector based curvature detection is used to analyze the gait pattern with different speeds. In another embodiment, Eigenvector based curvature detection is employed to detect static single limb stance (SLS) duration along with gait variables for evaluating body balance.

Abstract: Systems and methods for detecting spoofed or illegitimate GNSS signals. A processor receives GNSS data and processes this data to extract acceleration, angular velocity, and height or altitude variation data. For the same time period, sensor data from IMU (inertial measurement unit) sensors and from a barometer are received by the processor. From the sensor data, the processor extracts similar acceleration, angular velocity, and height variation data. These two sets of data are then correlated and correlation coefficients are calculated. These correlation coefficients are then used to calculate a decision statistic. The decision statistic is compared with a predetermined value and, if the decision statistic is below a predetermined value, then the GNSS data is considered to be illegitimate or spoofed.

Abstract: Methods, systems, and apparatus, including computer programs encoded on computer storage media, for determining voice characteristics are provided. One of the methods includes: obtaining speech data of a speaker; inputting the speech data into a model trained at least by jointly minimizing a first loss function and a second loss function, wherein the first loss function comprises a non-sampling-based loss function and the second function comprises a Gaussian mixture loss function with non-unit multi-variant covariance matrix; and obtaining from the trained model one or more voice characteristics of the speaker.

Abstract: An apparatus and digital signal processing means are disclosed for excision of co-channel interference from signals received in crowded or hostile environments using spatial/polarization diverse arrays, which reliably and rapidly identifies communication signals with transmitted features that are self-coherent over known framing intervals due to known attributes of the communication network, and exploits those features to develop diversity combining weights that substantively excise that co-channel interference from those communication signals, based on differing diversity signature, timing offset, and carrier offset between the network signals and the co-channel interferes. In one embodiment, the co-channel interference excision is performed in an appliqué that can be implemented without coordination with a network transceiver.

Abstract: Provided is a method of damping mechanical oscillations of plural wind turbines of a wind park commonly supplying electric energy to a grid, the method including: determining, for each of the plural wind turbines, a damping control signal for counteracting an oscillation of the respective wind turbine; supplying at least a subset of or a subset of modified versions of the damping control signals to respective wind turbines such that a sum of the supplied damping control signals is lower than a threshold.

Abstract: A method and device for identifying radar emission modes are provided.

Abstract: A system for providing operational control of a vehicle includes a first network device and control module. The first network device includes: polarized antennas; a transmitter transmitting an initiator packet via the polarized antennas from the vehicle to a second network device including a synchronization access word and a CW tone, one of the first and second network devices is implemented within the vehicle, the other one of the first and second network devices is a portable access device, and at any moment in time, at least one of the polarized antennas is not cross-polarized with an antenna of the second network device; and a receiver receiving a response packet from the second network device including the synchronization access word and the first CW tone. A control module determines a difference in RTT between the initiator and response packets and detects a range extension type relay attack.

Abstract: A method for detecting intrusions in a monitored volume in which: N tridimensional sensors acquire local point clouds in respective local coordinate systems; a central processing unit receives the acquired local point clouds and, for each sensor; computes updated tridimensional position and orientation of the sensor in a global coordinate system of the monitored volume by aligning a local point cloud acquired by the tridimensional sensor with a global tridimensional map of the monitored volume; and generates an aligned local point cloud on the basis of the updated tridimensional position and orientation of the sensor; the central processing unit monitors an intrusion in the monitored volume by comparing a free space of the aligned local point cloud with a free space of the global tridimensional map.

Abstract: It is disclosed to obtain a frequency transformed radiomap data set by applying a discrete frequency transform to an original radiomap data set. It is also disclosed to obtain a reconstructed radiomap data set by applying an inverse discrete frequency transform to a frequency transformed radiomap data set.

Abstract: A terrestrial network node of a terrestrial mobile communication network is operated to simultaneously serve terrestrial and aerial coverage on a same carrier frequency. Such operation includes directing a first reception beam towards an aerial radio node. A second reception beam is directed towards a user equipment in the terrestrial mobile communication network. The signal received in the first reception beam is filtered to create a replica of a signal transmitted by the aerial radio node as received by the second reception beam. The replica is subtracted from the signal received by the second reception beam.

Abstract: Disclosed, among other things is a wide area direction finding system comprising multiple radio frequency (RF) receiving units and a display computer. The RF receiving units may be in different geographic areas to make use of triangulation to precisely locate a target, allowing for increased area coverage and accuracy when locating a target. Locating a target may draw from real-time information using a “live mode,” or from a past event using a “history mode” on the display computer.

Abstract: Method and apparatus for responding to an emergency using orienteering methods. An Augmented Virtual Model (AVM) may assist in determining the nature of the emergency and a path to be taken by an emergency responder. By referencing the AVM on a smart device, such as one located in the visor of a firefighter, the emergency responder can quickly and easily locate a cause of the emergency and address it, as well as rescue lives endangered by the emergency.

Abstract: Methods and systems are presented in this disclosure that enable mobile devices without access to an active network connection (e.g. cellular, satellite or Internet network) to communicate between each other by sending and receiving data packets (e.g. text, location, or image) through a mesh of connected devices. A packet for forwarding is included into a mesh forwarding list at a mobile device, wherein the mesh forwarding list includes packets for forwarding to one or more mobile devices. The mobile device checks, in each packet within the mesh forwarding list, a list with at least one identifier of at least one wireless device that has already received the packet. The mobile device forwards the mesh forwarding list to the one or more wireless devices via at least one connection, based on the checked one or more identifiers.

Abstract: A technology is described for mitigating global positioning system (GPS) spoofer signals. A potentially spoofed GPS signal received via an antenna coupled to a GPS receiver can be identified. The potentially spoofed GPS signal can be applied to a spoofer signal nulling loop to generate a set of spoofer nulling weights. The set of spoofer nulling weights can produce a direction vector associated with the potentially spoofed GPS signal. The direction vector can be compared to a beamsteering vector. The potentially spoofed GPS signal can be determined as being a spoofer GPS signal when a misalignment between the direction vector and the beamsteering vector is above a defined threshold. The spoofer GPS signal can be converted to a spoofer mitigation signal that is applied to satellite track channels of the GPS receiver. The spoofer mitigation signal can produce a spatial null in a direction of the spoofer GPS signal.

Abstract: Apparatuses, methods, and systems for grouping antenna elements to enhance an antenna array response resolution, are disclosed. One method includes selecting a plurality of groups of antenna elements from an antenna array, wherein each group includes a plurality of antenna elements of the antenna array, determining an optimal phase setting for a beam directed from each group to a target device, and characterizing each of the groups including adjusting a phase of an electronic signal passing through each of the antenna elements of the group based on the optimal phase setting of the group, adjusting an amplitude ai of the electronic signal the passing through each of the antenna elements of the group to compensate for a loss of antenna array gain of the antenna array due to grouping of the antenna elements, and storing the adjusted phase and adjusted amplitude for each of the antenna element.

Abstract: To determine a location of a client device in a wireless network having at least first and second network devices, with known locations, one of the network devices transmits a message to the other network device and the other network device responds with an acknowledgement message. A client device receives the message and the acknowledgement message as well as respective times indicating actual times at which the message and the acknowledgement message were processed by one of the first and second network devices. The client device determines its location based on the times at which it received the message and the acknowledgement message and the difference between the actual processing times. This location may be refined by determining an angle between the client device and at least one of the network devices having multiple antennas and being configured for steered beam communications.

Abstract: The present disclosure relates to methods and devices for Channel State Information, (CSI) prediction. More particularly the disclosure pertains to predicting CSI for a dynamic channel that is varying over time, e.g. because the receiver is moving. This object is obtained by a method performed in a first wireless node of predicting CSI of a dynamic wireless channel H between the first wireless node and a second wireless node. The method comprises deriving channel covariance estimates Ck(n), . . . , Ck(n?M) of the dynamic wireless channel H, estimating one or more channel properties of the dynamic wireless channel H, wherein one of the estimated channel properties defines a spectrum spread of the dynamic wireless channel H, and determining a covariance prediction filter, based on the estimated one or more channel properties.

Abstract: A method for correction of a sea surface state can include receiving geophysical data from a seismic survey, wherein the seismic survey utilizes a plurality of receivers disposed in a body of water and at least one source in the body of water, actuated at a plurality of shot points. The method can include identifying, in the geophysical data, a wavefield based on the actuation of the at least one source, and determining, based on the identified wavefield, a sea surface state at the at least one source at one of the plurality of shot points.

Abstract: An array antenna includes a plurality of antennas capturing a coming radio wave and outputting a received signal respectively. An A-D converter converts the received signal to a digital signal, and a frequency detector detects a frequency of the received signal. A sparse signal processor calculates complex amplitudes, which are coefficients for base vectors, each of the base vectors expressing phases of the antennas of the array antenna receiving a radio wave coming from each direction in determined directions, used in expressing the received signal as a linear sum of a finite number of the base vectors, separates the received signal into direction signals for each direction, and calculates the phase of the each of the direction signals. A signal synthesizer aligns the phases of the direction signals using phase differences calculated from phases of the complex amplitudes, and synthesizes the direction signals.

Abstract: An apparatus for providing directional audio capture may include a processor and memory storing executable computer program code that cause the apparatus to at least perform operations including assigning at least one beam direction, among a plurality of beam directions, in which to direct directionality of an output signal of one or more microphones. The computer program code may further cause the apparatus to divide microphone signals of the microphones into selected frequency subbands wherein an analysis performed. The computer program code may further cause the apparatus to select at least one set of microphones of the apparatus for selected frequency subbands. The computer program code may further cause the apparatus to optimize the assigned at least one beam direction by adjusting a beamformer parameter(s) based on the selected set of microphones and at least one of the selected frequency subbands. Corresponding methods and computer program products are also provided.

Abstract: Provided are architectures, systems, methods, and computer program products for real-time object locating and position determination using frequency channel diversity for transmitting and receiving position determination signals including bursts of location signals. Channelized frequency diversity of a short burst of small location signals that “hop” across multiple frequency channels is used to collectively produce a quasi-wideband position determination signal. Object tags operating with frequency channel diversity for transmitting location signals of position determination signals require low power consumption, but can still efficiently provide adequate position determination signals for reliable position determination.

Abstract: A wireless digital audio system includes a portable audio source with a digital audio transmitter operatively coupled thereto and an audio receiver operatively coupled to a headphone set. The audio receiver is configured for digital wireless communication with the audio transmitter. The digital audio receiver utilizes fuzzy logic to optimize digital signal processing. Each of the digital audio transmitter and receiver is configured for code division multiple access (CDMA) communication. The wireless digital audio system allows private audio enjoyment without interference from other users of independent wireless digital transmitters and receivers sharing the same space.

Abstract: A Software Defined Radio Earth Atmosphere Imaging system comprising at least one imager, which comprises: a radio wave emitter configured to emit a sky wave, a ground wave and a first time signal; a radio wave detector, the radio wave detector including a two dimensional array of radio wave receivers, the radio wave detector for receiving a carrier wave and the ground wave and transmitting a second time signal; a vector network analyzer including a Global Navigation Satellite System and at least one synchronization clock, the vector network analyzer in electrical communication with the radio emitter via a first wire and with the radio wave detector via a second wire, the wires for transmitting the time signals; a software defined radio in electronic communication with the vector network analyzer; and a computing device, the computing device in electronic communication with the vector network analyzer.

Abstract: A method and apparatus for generating a covariance matrix during adaptive beamforming of a multi-beam antenna. The method uses an upper right triangle of the covariance and time sharing of complex conjugate multipliers to efficiently compute the covariance matrix. In addition, a variable number of beams may be selected in the covariance matrix according to an operating environment of the multi-beam antenna.

Abstract: A method and apparatus are provided for calibrating a wireless access point comprising an array of multiple (m) antennas denoted Ai (i=1 . . . m), each antenna having a respective internal phase offset ?i. The method comprises receiving a signal from at least one transmitter located at a substantially known bearing from the wireless access point. The method further comprises determining an estimated value for each internal phase offseti such that an angle of arrival (AoA) spectrum calculated for the received signal on the basis of said estimated values matches the known bearing, wherein said AoA spectrum is calculated by treating said multiple antennas as a phased array. A method and an apparatus are also provided for calibrating a wireless access point comprising first and second arrays of multiple antennas, each antenna array having a respective radio unit, and each antenna in an array having a respective internal phase offseti.

Abstract: It is disclosed to obtain a frequency transformed radiomap data set by applying a discrete frequency transform to an original radiomap data set. It is also disclosed to obtain a reconstructed radiomap data set by applying an inverse discrete frequency transform to a frequency transformed radiomap data set.

Abstract: Methods and systems are presented in this disclosure that enable mobile devices without access to an active network connection (e.g. cellular, satellite or Internet network) to communicate between each other by sending and receiving data packets (e.g. text, location, or image) through a mesh of connected devices. A packet for forwarding is included into a mesh forwarding list at a mobile device, wherein the mesh forwarding list includes packets for forwarding to one or more mobile devices. The mobile device checks, in each packet within the mesh forwarding list, a list with at least one identifier of at least one wireless device that has already received the packet. The mobile device forwards the mesh forwarding list to the one or more wireless devices via at least one connection, based on the checked one or more identifiers.

Abstract: A measurement system is provided. The measurement system comprises a device under test comprising at least one antenna, at least one measurement antenna, and a signal analysis unit. In this context, the location of the at least one antenna of the device under test is unknown with respect to the device under test, whereas the signal analysis unit is configured to perform at least one near-field measurement with respect to the device under test with the aid of the at least one measurement antenna. In addition to this, the signal analysis unit is further configured to locate the at least one antenna of the device under test on the basis of the at least one near-field measurement in order to obtain position data of the at least one antenna of the device under test.

Abstract: The method and apparatus for angle of arrival estimation are used for estimating the angle of arrival of a received signal by a switched beam antenna array and a single receiver. The switched beam antenna array first collects an omnidirectional signal to be used as a reference signal. A main beam thereof is then switched to scan an angular region of interest. The collected signals from the switched beams are cross-correlated with the reference signal. The cross-correlation coefficient is the highest at the true angle of arrival and relatively negligible otherwise. The collected signal from each beam angle is cross-correlated with the omnidirectional reference signal to determine the angle of arrival of the received signal.

Abstract: Methods and systems for improving time-semblance processing of acoustic data are disclosed. Acoustic data is obtained from a tool in a formation. A delay filter is then designed and applied to the obtained acoustic data to obtain delayed acoustic data. Time semblance is then applied to this delayed acoustic data.