Abstract: A method for detecting anomalies in a positioning system comprises receiving, for a plurality of locator devices (ANC1, ANC2, ANC3, ANC4), respective location indicators associated with at least one mobile device (TG1, TG2, TG3), determining a position of the at least one mobile device (TG1, TG2, TG3) based on the received location indicators, acquiring, for at least one of the location indicators received, a confidence indicator associated with the at least one of the location indicators, determining, for each acquired confidence indicator, whether a confidence criterion is met, and storing an anomaly indicator in an anomaly cache, if the confidence criterion is not met, wherein each anomaly indicator is associated with the locator device, for which the location indicator is received; and generating an anomaly alert message for at least one of the locator devices based on an evaluation of the anomaly indicators that are stored for the at least one of the locator devices.

Abstract: The present disclosure relates to processes, devices, and computer program products for estimating parameters of a wireless communication channel using machine learning, and includes receiving at least one sample of raw data via the wireless communication channel, processing the at least one sample using a machine learning inference algorithm to obtain a first estimated value, processing the at least one sample using a signal processing algorithm to obtain a second estimated value, acquiring a first confidence value for the first estimated value, acquiring a second confidence value for the second estimated value, evaluating the first confidence value and the second confidence value, and providing either the first estimated value or the second estimated value or a combination of the first and the second estimated value as the at least one estimated parameter based on the evaluation.

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: A method and apparatus are provided for detecting GNSS signal lock. An example method includes tracking a plurality of signals received from a respective plurality of satellites in the GNSS, and calculating an individual frequency spectrum for each tracked signal in the plurality, to produce a plurality of individual frequency spectra. The example method further includes combining one or more values from several of the individual frequency spectra, to produce one or more combined values; and detecting an ensemble signal lock condition based at least in part on the one or more combined values.

Abstract: An antenna (100) comprising a plurality of like antenna elements (10) is disclosed. Each antenna element comprises: a radiating element (12, 13); a feed point (14); and a short to ground (16). The elements are spaced apart in different positions and oriented in different directions. Also provided are a GNSS receiver module (150) comprising the antenna, and a method of manufacturing the antenna. The antenna may be used, in particular, for receiving a circularly polarised signal.

Abstract: The disclosure relates to an antenna assembly, a receiver assembly, communication methods for the same and a system. The antenna assembly comprises a signal line for connecting the antenna assembly to a single line communication cable. The antenna assembly further comprises an antenna, arranged to receive a radio frequency signal and to apply the radio frequency signal to the signal line of the antenna assembly. The antenna assembly further comprises an antenna multiplexer, arranged to separate a superimposed signal from the radio frequency signal on the signal line, wherein the superimposed signal comprises a supply voltage for the antenna assembly and a communication signal. The antenna assembly further comprises an antenna controller, arranged to receive the communication signal and to perform a monitoring and/or a control operation in response to the communication signal.

Abstract: An example method of determining a position of a mobile device includes, for each of a plurality of anchor points, receiving respective relative position information between the respective anchor point and the mobile device such that the received relative position information for the plurality of anchor points forms a set of position information, each relative position information including at least one of: a direction between the respective anchor point and the mobile device, a distance between the respective anchor point and the mobile device, or a direction and a distance between the respective anchor point and the mobile device.

Abstract: The present disclosure relates to a method for determining an angle of arrival, AoA, of received radio frequency, RF, measurement signals. The method comprises obtaining measurement data based on the received RF measurement signals from an antenna array, wherein the RF measurement signals are representative of multiple frequency channels. The method further comprises determining power spectra, comprising determining at least one power spectrum for each of the multiple frequency channels by using the measurement data. The method further comprises providing a machine learning algorithm, which is pre-trained to determine an AoA based on power spectra of multiple frequency channels. The method further comprises determining the AoA of the received RF measurement signals by using the machine learning algorithm and the determined power spectra.

Abstract: A method is provided for calibrating a vehicle-mounted GNSS antenna. The method comprises measuring a response of the antenna, while the antenna is mounted on the vehicle. Based on the measured response, data characterizing a group delay variation of the antenna is calculated. The data may be used to correct ranging measurements derived from GNSS signals received via the vehicle-mounted antenna. Alternatively or in addition, the data may be used in estimating the integrity of a position fix.

Abstract: A method and apparatus are provided for estimating characteristic differences between wireless signals transmitted from the same location in spaced apart frequency ranges. Also provided are a method and apparatus for estimating a combined time of arrival of the wireless signals, using the characteristic differences. A further method is provided, for identifying that two signals have been transmitted from the same location. Also disclosed is a method of maintaining a database of characteristic difference information.

Abstract: An antenna is provided comprising a substrate formed of a dielectric material. The substrate has an upper surface, a lower surface, and one or more side surfaces connecting the upper surface with the lower surface. The antenna further comprises a conductive patch on the upper surface of the substrate; a first conductive strip on one of the one or more side surfaces; and a second conductive strip on one of the one or more side surfaces. The first and second conductive strips are arranged at opposing sides of the conductive patch. The antenna further comprises a ground plane, wherein the first and second conductive strips are galvanically isolated from the conductive patch and galvanically connected to the ground plane.

Abstract: The present disclosure relates to a method for synchronizing an encoded signal, in particular a GNSS signal. The method comprises receiving an input signal comprising a first signal component and a second signal component, wherein a sequence of N bits of the first signal component and a sequence of M bits of the second signal component are known a priori. The method further comprises determining a first logical sequence based on a plurality of cross-product operations formed between pairs of vectors obtained from a plurality of received symbols of the first signal component and the second signal component of the received input signal.

Abstract: An antenna includes an optically transparent substrate layer having a first surface and an opposing second surface; a radiating element having a first mesh structure and disposed on the first surface of the substrate layer; a ground plane having a second mesh structure formed on the second surface of the substrate layer; at least two feed lines configured to connect the radiating element to an external circuit; and at least two stubs connected to the radiating element.

Abstract: A method for determining a protection level of a position estimate using a single epoch of GNSS measurements, the method includes: specifying a prior probability density P(x) of a state x; specifying a system model h(x) that relates the state x to observables z of the measurements; quantifying quality metrics q associated with the measurements; specifying a non-Gaussian residual error probability density model ƒ(r|?, q) and fitting model parameters ? using a set of experimental data; and defining a posterior probability density P(x|z, q, ?); estimating the state x; and computing the protection level by integrating the posterior probability density P(x|z, q, ?) over the state x.

Abstract: A method and apparatus are provided for demodulating a wireless signal modulated by phase-shift keying. The signal comprises a plurality of symbols. The method includes: obtaining a first sequence of samples based on the signal; converting the first sequence of samples to a first sequence of frequency domain samples; selecting, as a decision variable, the sample that has the maximum magnitude among the first sequence of frequency domain samples; and identifying a symbol or a symbol-transition based on the decision variable.

Abstract: A system and a method for secure communications over a network, the method comprising: receiving a data packet from a first device, the data packet comprising an encrypted data part and a metadata part, the metadata part comprising a cleartext part and removable metadata, the removable metadata comprising a network access code that is authenticatable by means of a network access key; validating the data packet, wherein validating the data packet comprises authenticating the network access code using the network access key; removing the removable metadata from the data packet after validating the data packet, thereby altering the data packet; and transmitting the altered data packet to a second device. The system comprises a first, a second, and a third device. The third device may comprise a receiver and a transmitter, and a validator that comprises a processor and a memory.

Abstract: Methods and apparatus for transmitting signals, the transmitter including a memory storing instructions and a controller configured to execute the instructions to cause the transmitter to determine whether a value of transmitter power is less than a threshold, responsive to a determination that the value of transmitter power is less than the threshold: mix a baseband signal with a first oscillator signal to produce a very-low intermediate frequency (VLIF) signal; mix the VLIF signal with a second oscillator signal to produce a radio frequency (RF) signal, and transmit the RF signal.

Abstract: A navigation receiver, a navigation system and a method of time stamping asynchronous sensor measurements is provided. Sensor measurement data is received at a first port. A signal pulse is received at a second port. The signal pulse represents a time of measurement according to a first time domain of the received sensor measurement data. Based on the received signal pulse, a timestamp according to a second time domain is generated. The generated timestamp is associated in the second time domain with the received sensor measurement data.

Abstract: An antenna includes a substrate layer having a first surface and an opposite second surface, the second surface having a metallization layer; a conductive layer disposed on the first surface of the substrate layer; a slot formed in the conductive layer, the slot including a first part and a second part that are symmetric to each other about a diagonal of the conductive layer; and at least one feed point on the conductive layer and spaced from the slot by a predetermined distance.

Abstract: Methods and apparatus for detecting a potential fault in a positioning device, the apparatus including at least one memory for storing instructions, and at least one controller configured to execute the instructions to perform operations including obtaining information about a received signal received by the positioning device, the information including at least one of a control parameter or an estimation of bias based on the received signal; determining whether the potential fault is detected, based on the information and a detection threshold; and in response to a determination that the potential fault is detected, generating an indication that the potential fault is detected.