Abstract: The disclosure is directed to a method for measuring an angle of arrival (AoA), with a steerable phased array. The method would include but not limited to: receiving a signal by the steerable phased array with a first steering angle and with a second steering angle; obtaining a first power-related information (PRI1) of the signal corresponding to the first steering angle; obtaining a second power-related information (PRI2) of the signal corresponding to the second steering angle; and calculating an AoA of the signal based on the first power-related information and the second power-related information, wherein the first steering angle is different from the second steering angle, and an absolute difference between the first steering angle and the second steering angle is less than FNBW/2.

Abstract: The detection and identification of unmanned aerial vehicles (UAVs) from a radio wave measurement result based on artificial intelligence (AI) are provided. A method of operating an apparatus to detect unmanned aerial vehicles (UAVs) includes generating a spectrogram, determining a first region to find a direction of the UAVs in the spectrogram, determining a direction of a first UAV of the UAVs based on signal values in the first region, determining a second region to identify a type of the first UAV in the spectrogram, and identifying the type of the first UAV based on signal values in the second region.

Abstract: Disclosed is a BeiDou satellite ephemeris prediction method and system based on a water-wave parallel network. The method includes: receiving broadcast ephemeris data; calculating according to the broadcast ephemeris data to obtain a sequence of extrapolation errors and historical extrapolated states; and inputting the sequence of extrapolation errors and the historical extrapolated states into a pre-trained prediction model to output an error prediction result. The system includes: a data receiving module, a dynamical calculation module, an error prediction module and a correction module. The present disclosure allows for accurate ephemeris prediction at a lower computational cost, and can be widely applied in the field of trajectory prediction.

Abstract: An antenna system of a satellite may consist of an antenna receiver that is coupled to a plurality of flexible couplings. The couplings may each be affixed to one or more antenna elements. The couplings may be deployed in space in an uncontrolled manner. Additionally, the spacing between the couplings, and in turn the antenna elements, may be spaced in an uncontrolled manner. The antenna elements may have no pointing requirements. The antenna system may receive training signals and associate an antenna element to a time of arrival based on the training signal. Upon receiving a data signal, the antenna system may apply coefficients determined from the association of the antenna element to the time of arrival to the data signal to discover wanted signal coherence among the antenna elements.

Abstract: Disclosed is an ultra-wideband (UWB) system and, more particularly, a UWB system capable of optimizing UWB operation for vehicles through hopping. The UWB system includes a memory in which a UWB communication program is embedded and a processor which executes the program. The processor performs UWB time-hopping and frequency-hopping to establish a communication channel.

Abstract: A method and apparatus are provided for spoofing detection in the context of a vehicle-based GNSS receiver. An attitude estimate of the vehicle is obtained. A velocity estimate is calculated based on measurements provided by the GNSS receiver. The method comprises projecting the velocity estimate to a body frame of the vehicle, using the attitude estimate; deriving a detection parameter from the projected velocity estimate; and comparing the detection parameter with a detection threshold, in order to detect spoofing.

Abstract: An assisted satellite positioning system based on detecting signals from a number of satellites includes: (a) a mobile receiver; and (b) a base station communicating with the receiver over a low-power wireless communication network, the base station providing ephemeris data of a selected number of the satellites, but not all, using a compressed data format. The ephemeris data may include data concerning doppler frequency variations or elevation variations of the selected satellites over a predetermined time interval. The doppler frequency variations and the elevation variations may be represented in the compressed format by coefficients of a polynomial function of time. The polynomial function may be weighted to have lesser relative errors in larger doppler frequencies than lesser doppler frequencies, or to have lesser relative errors in lesser elevations than larger elevations. In one implementation, the low-power wireless communication network—such as a LoRa network—that has a range of at least 10 miles.

Abstract: An example method performed at a mobile device for determining a position may comprise receiving correction data associated with (1) a first pseudorange measurement of a first GNSS signal sent from a satellite vehicle on a first GNSS carrier frequency and (2) a second pseudorange measurement of a second GNSS signal sent from the satellite vehicle on a second GNSS carrier frequency. The method also may comprise measuring a third GNSS signal sent from the satellite vehicle and received at the mobile device on a third GNSS carrier frequency, to generate a third pseudorange measurement. The method also may comprise determining the position of the mobile device using (a) the third pseudorange measurement of the third GNSS signal on the third GNSS carrier frequency and (b) the correction data associated with the first pseudorange measurement and the second pseudorange measurement.

Abstract: A base station selects, in response to a location request for a UE, RIS(s) to use for positioning purposes for the UE. The base station performs a process with the selected RISs to determine information used to configure the UE with RS configuration for using the selected RIS(s) for the positioning purposes. The base station sends the RS configuration to the UE. An RIS receives signals including RSs to be used for positioning purposes for a UE. The RIS time stamps the signals with the RSs and reflects signals including the RSs and corresponding time stamps. A UE receives a reference signal configuration for using RIS(s), receives RSs based on the configuration, and receives signals comprising RSs that have been reflected from the RIS(s). The UE performs timing estimates based on the received signals and sends indication of the timing estimates toward the base station.

Abstract: A method for determining an instantaneous phase difference between time bases of at least two location anchors for a desired point in time (t), each of the location anchors having transmitting and receiving access to a joint broadcast transmission medium and a respective time base for measuring time, wherein a first of the location anchors broadcasts a first broadcast message at least twice; the first location anchor and at least a second of the location anchors receive the first broadcast messages; the second location anchor broadcasting a second broadcast message at least twice; and the second location anchor and at least the first location anchor receive the second broadcast messages. The location server calculates the instantaneous phase difference from a determined first and second clock model functions and from a time elapsed between a reference point in time and the desired point in time t.

Abstract: A satellite Automatic Identification System (AIS) is for tracking a plurality of maritime vessels. The AIS may include a ground AIS server and a constellation of Low-Earth Orbit (LEO) satellites in communication with the ground AIS server. Each LEO satellite may include an AIS payload configured to receive AIS messages from the plurality of maritime vessels and determine therefrom reported vessel position data, determine actual signal arrival measurements for the AIS messages, and determine a potential spoofing maritime vessel based upon the reported vessel position data and actual signal arrival measurements and send a potential spoof alert to the ground AIS server. The ground AIS server may be configured to perform time sequenced pairwise differential calculations of the actual signal arrival measurements from at least one of the AIS payloads and for the potential spoofing maritime vessel to estimate a position of the potential spoofing maritime vessel.

Abstract: An antenna null steerer in a wireless network determines the conformance of a radio frequency signal received by multiple antennas to the protocol of the wireless network. When the received radio frequency signal is conformant to the protocol, the current antenna pattern is maintained. When the received radio frequency signal is non-conformant to the protocol, nulls are iteratively generated in the antenna pattern until the RF signal becomes conformant to the protocol and/or the maximum number of nulls are present in the antenna pattern.

Abstract: This specification relates to systems and methods for determining eigenvalues and eigenvectors of a covariance matrix, for example for use in eigen-beamforming in MIMO systems. According to a first aspect of this specification, there is describes a method comprising: receiving an input covariance matrix; and determining one or more eigenvalues and/or eigenvectors of the matrix iteratively using gradient ascent, wherein each iteration of the gradient ascent has a step size, ?, that maximises a Rayleigh quotient along the gradient.

Abstract: A GNSS receiver includes at least two antennas, a satellite direction acquisition module, an estimation module, and a determination module. A satellite direction acquisition module acquires the direction when viewing the satellite corresponding to the GNSS signal received by the antenna based on the satellite orbit information. The estimation module estimates the arrival direction of the GNSS signal on the basis of the difference in timing when the GNSS signal is received by the plurality of antennas. The determination module compares the direction in which the satellite is viewed from the antenna with the arrival direction estimated by the estimation module to determine whether the GNSS signal received by the antenna is a direct GNSS signal based on a direct wave from the satellite or an NLOS GNSS signal.

Abstract: Disclosed are a method and an apparatus for determining time of arrival, a signal receiving device, and a non-transitory computer readable storage medium. The method for determining time of arrival includes: generating time of arrival correction information according to front edge information of theoretical autocorrelation waveforms of positioning signals having different fading values; calculating a front edge slope corresponding to a front edge reference point of a correlation waveform of an actually received signal; and determining target correction information from the time of arrival correction information according to the front edge slope, and determining the time of arrival of the actually received signal based on the target correction information.

Abstract: A method and device for determining a time of arrival (TOA), a terminal device, and a non-transitory computer-readable storage medium are disclosed. The method may include: determining a detection start time on a correlation waveform based on a leading edge detection threshold; determining a noise threshold on the correlation waveform, and determining a quasi-TOA according to the detection start time; and determining the TOA according to data information in a target area of the correlation waveform and the noise threshold, where the target area is determined based on the quasi-TOA and a detection length.

Abstract: Systems and methods are described for determining a peripheral's location based on observations from a plurality of centrals. A central may periodically transmit its location and observations of peripherals to a backend. The backend may match the location of the central with one or more observations of a peripheral to estimate a location of the peripheral. The backend may receive observations of the same peripheral from a plurality of centrals. The backend may aggregate estimated locations to triangulate a more precise location of the peripheral.

Abstract: A system can be used with a drone delivery service that facilitates a service delivery via at least one drone delivery device. The system includes a code generator configured to generate beacon data that identifies a subscriber. A beacon generator is configured to generate a wireless homing beacon that indicates the beacon data, wherein the wireless homing beacon is detectable by the at least one drone delivery device to facilitate the service delivery to the subscriber by the drone delivery device at a location selected by the subscriber and a network interface is configured to communicate via a network. The system receives delivery image data captured after the service delivery by the drone delivery device.

Abstract: A system includes a plurality of wireless transmitters and a processor configured to: receive, from a mobile device, signal strengths of signals from the wireless transmitters as detected by the mobile device. The processor is also configured to determine a location of the mobile device in a vehicle, based on a distance from the mobile device to each of the wireless transmitters, as indicated by the received signal strengths and store the location of the mobile device as an occupant location.

Abstract: A method is disclosed. In various examples, the method may include receiving an instruction for generating a signal comprising a ranging signal and a data signal. The method may also include transmitting, via a terrestrial transmitter for transmitting radio waves having encoded messaging information and timing information for one or more of positioning, navigation and timing, the signal at least partially responsive to the instruction. The signal may include a pulse group comprising a number of ranging pulses and a number of data pulses subsequent to the number of ranging pulses. Respective ones of the number of data pulses may have a phase of either a positive-going phase or a negative-going phase. Information may be encoded using the either positive-going phases or negative-going phases of the data pulses.