Abstract: A base station may allocate wireless communication resources to configure a synthetic wireless communication signal for use as a radar signal. The synthetic wireless communication signal may be configured according to a wireless communication protocol of a wireless communication network that is associated with the base station. The base station may transmit, from an antenna and toward an area associated with the base station, the synthetic wireless communication signal. The base station may detect a reflected signal that is associated with the synthetic wireless communication signal. The base station may process the reflected signal to generate radar data; and perform an action associated with the radar data and the area.

Abstract: A preprocessing system includes a first port, where one end of the first port is coupled to a first switch, and the other end of the first port is suspended, where the first switch has a connecting end configured to couple to a first interface and is configured to connect a filter and the first interface, a second port configured to receive a first signal or a second signal, where the filter is configured to filter the first signal to obtain a first positioning signal and a second positioning signal, provide the first positioning signal for the first switch, and provide the second positioning signal for a second interface of a global navigation satellite system (GNSS) chip to adapt to a plurality of antenna configuration types and to achieve universality.

Abstract: Movement information is calculated with high accuracy, without being influenced by the number of GNSS signals receivable by each of a plurality of antennas. A movement information calculating device includes a plurality of antennas, a clock generator, a plurality of GNSS receivers, and an arithmetic logical unit. The plurality of antennas, each receives a GNSS signal. The clock generator generates a clock signal. The plurality of GNSS receivers are connected to the respective antennas, and share the clock signal from the clock generator and calculate GNSS observed values by using the shared clock signal and the GNSS signals, respectively. The arithmetic logical unit calculates movement information including a speed of a movable body based on the GNSS observed values from the plurality of GNSS receivers.

Abstract: Systems, methods, and computer-readable media are described for compact radar systems. In some examples, a compact radar system can include a first set of transmit antennas, a second set of receive antennas, one or more processors, and at least one computer-readable storage medium storing computer-executable instructions which, when executed by the one or more processors, cause the radar system to coordinate digital beam steering of the first set of transmit antennas and the second set of receive antennas, and coordinate digital beam forming with one or more of the second set of receive antennas to detect one or more objects within a distance of the radar system.

Abstract: A direction detection device for detecting a received-wave arrival direction of a received wave, and includes: antennas for receiving the received wave; an intensity difference imparting unit that imparts intensity differences different depending on the received-wave arrival direction to intensities of the received wave; a storage unit that stores an intensity difference table in which the intensity difference between two of the antennas is associated with the received-wave arrival direction, for each combination of any two of the antennas; a detector that detects the intensity difference between the two antennas of the received wave; an extractor that extracts, from the intensity difference table, received-wave arrival directions corresponding to the intensity difference detected by the detector, for each combination; and a comparator that compares the received-wave arrival directions extracted by the extractor between the combinations of the antennas to acquire a matched received-wave arrival direction as a

Abstract: An RCS reduction surface for reducing a radar cross section of an object is described. The RCS reduction surface comprises at least one absorber portion, wherein the absorber portion is configured to absorb radar waves. The RCS reduction surface further comprises at least one reflecting portion, wherein the reflecting portion is configured to reflect radar waves. A first plane being associated with a top surface of the absorber portion and a second plane being associated with a top surface of the reflecting portion are spaced from each other by a predefined distance. The predefined distance is configured such that radar waves with a predefined wavelength range that are reflected at the absorber portion and at the surface of the reflecting portion interfere destructively with each other. Further, an RCS reduction member and a radar test system are described.

Abstract: A centralized cooperative positioning method includes: caching measurements of nodes in multiple time slices up to the current time slice; calculating location information of the nodes in the multiple time slices to obtain trajectory of the nodes in the multiple time slices; performing initial state estimations of the nodes based on measurements of a single time slice; and using the initial state estimations as initial solution values, performing the joint time-space processing on the measurements of the nodes in the multiple time slices based on trajectory constraints, to obtain a state estimation of each node at the current time slice, in which the state estimation includes an estimated value of a location of the node.

Abstract: A system for measuring a water-filled structure includes a measurement device. The measurement device comprises a sensor carrier with a first end arranged below water and a second end arranged above the water. At least one measurement sensor is positioned on the first end of the sensor carrier and is configured to measure the water-filled structure by capturing measurement data. An acceleration sensor is provided and a tachymeter is positioned outside of the water-filled structure. The position of the tachymeter is determined using GNSS measuring points configured to receive GNSS signals from satellites in a global navigation system. A control unit is configured to determine at least one of a current position of the measurement device and an orientation of the measurement device based on: (1) measuring data from the acceleration sensor; (2) the GNSS signals received by the GNSS measuring points; and (3) measuring data captured by the tachymeter.

Abstract: A non-transitory computer-readable medium storing a plurality of computer-readable instructions executable by a processor, wherein execution of the instructions configures the processor to: obtain location data representing a ground path of a flight of an object; determine, from the location data, a first ground distance and a second ground distance traversed by the object during an ascent phase and a descent phase of the flight of the object, respectively; determine an initial angle of the flight of the object; determine an initial airspeed of the object based on the determined initial angle; determine an air drag value for the object during the flight based on the determined initial angle and the determined initial airspeed; output a flight path of the object, the flight path representing a three-dimensional path travelled by the object during the flight and determined based on the initial angle, the initial airspeed and the air drag value.

Abstract: Techniques for monitoring devices to use ultrasonic signals to detect and track the locations of moving objects in an environment. To determine distance information, the monitoring devices emit a frequency-modulated continuous wave (FMCW) signal at an ultrasound frequency range. Reflections of the FMCW ultrasonic signal are used to generate time-of-arrival (TOA) profiles that indicate distances between the monitoring device and objects in the environment. The reflections can be processed to suppress undesirable interferences, such as reflections off non-mobile objects in the environment (e.g., walls, furniture, etc.), vibrations off the floorings or the ceilings, etc. After processing the reflections, a heatmap can be used to plot the intensity of the reflections for the different TOAs of the reflections, and depict the movement of the user over time. Finally, a Kalman filter is used to smooth the peaks in the intensity values on the plot, and determine the trajectory of the human.

Abstract: A controller for a communication and ranging apparatus wherein the apparatus is configured to transmit both a data signal and a ranging signal, wherein the controller is configured to: determine a scheduled transmission event of the data signal; determine a scheduled transmission event of the ranging signal; determine if the scheduled transmission events will occur within a predetermined time window of each other; if it is determined that the scheduled transmission events will occur within a predetermined time window of each other, then determine a priority signal and a secondary signal, wherein: the priority signal is one of the data signal and the ranging signal; and the secondary signal is the other of the data signal and the ranging signal; and provide signaling configured to prevent the scheduled transmission event of the secondary signal from being transmitted such that only the scheduled transmission event of the priority signal is transmitted.

Abstract: A plurality of positional sensing devices are situated at regular intervals within an environment and collect data for tracking objects moving within the environment. Phase shift of modulated Doppler pulses reflected from the sensing devices to objects are measured and converted into positional data indicating positions of detected objects within the environment. Associated timestamp data is also collected by the positional sensing devices. The positional data and associated timestamp data is aggregated from the plurality of positional sensors, and the aggregated positional data and is clustered to determine point clouds which are associated with the detected objects. The clusters are tracked by tracklets that track the position of each cluster over time. Trajectories for each detected object are determined by connecting tracklets together that are associated with the same detected object.

Abstract: The invention discloses a method for estimating the air propagation delay of a direct wave, wherein an azimuth, an elevation angle and a total delay of a multipath wave reaching a receiving end are obtained through a receiving device; a departure angle of a reflected wave is obtained using a geometric relationship of wave reflection; a hypothetical point on a direct wave ray is selected as a transmitting end, and hereby the air propagation delay of the direct wave and the position of a reflection point of the reflected wave are calculated; the propagation delay and distance of the reflected wave are calculated according to the total delay of the direct wave and the reflected wave and the position of the hypothetical point. The invention can obtain the air propagation delay of the direct wave, thereby obtaining a propagation distance of the direct wave and fulfilling the requirements of ranging and positioning.

Abstract: In one aspect, a method of determining a location of a user within an indoor space, includes emitting a radiofrequency signal into the indoor space, receiving backscattered training radiofrequency signals, including multipath, for at least one location within the indoor space, converting the received training signals into a point cloud for each location of the at least one location, assigning a signature for each location based on the point cloud for each location, receiving additional radiofrequency signals, including multipath, converting the additional radiofrequency signals into an additional point cloud, and determining a location of the user by comparing the additional point cloud to the assigned signatures.

Abstract: A method and system device provides a unique object identification process by obtaining information from one or more of radar signals, infrared signals, optical signals, audio signals, and other signals. The method includes continuously receiving object data at the device, applying by a machine learning system, a set of parameters to process the object identification and confidence level, and outputting or updating the object identification, confidence level, and actionable recommendations. The radar data includes a Doppler signature having a wrapped signal due to a sampling rate of the radar system. The Doppler signature is used to train the machine learning system to identify drone types.

Abstract: A method is disclosed for converting source radar data of a source configuration of a radar system target radar data of a target configuration. The method comprises: providing a source array of grid cells for source reflex locations; determining, for each respective grid cell in the source array, a probability or frequency that source reflex locations are located in the respective grid cell; forming a source tensor including the source array populated with the probability or frequency for each grid cell; transforming the source tensor into a target tensor including a target array of grid cells for the target reflex locations and indicating the probabilities or frequencies of the target reflex locations for each respective grid cell; and generating the target radar data by sampling the location coordinates of the target reflex locations.

Abstract: Systems, methods, and circuitries are disclosed for compressing radar data. In one example, a method includes storing radar data in a memory, the radar data being stored in a data cube having a slow-time dimension, a fast-time dimension, and a channel dimension. The data cube is divided into one or more zones. For each zone a number of data matrices is selected based on a compression factor. Sets of data matrices containing the number of data matrices are formed and, for each set of data matrices, for each data matrix, the data vectors are coded to generate a coded data matrix. A coding for data vectors in a data matrix is the same and a coding for different data matrices is different. The coded data matrices are combined to generate a compressed data matrix for the zone and the compressed data matrices for the one or more zones are stored.

Abstract: Vehicles with adjustable metamaterial systems, integrated on the outside or inside of their non-conductive fuselage, have the ability to control their radar cross section dynamically for the purposes of evading detection or spoofing their size by looking larger or more numerous. The frequency response of a metamaterial system can be obtained by combining the RF properties of the individual metamaterial layers that comprise it. A first metamaterial layer that can controllably switch between transmissive and reflection in a relevant frequency band and a second absorptive layer results in a controllable radar cross-section with the ability of controlling the amplitude of the reflected radar pulse. The first layer can be modulated with a repetitive waveform to change the phase of a reflected wave that results in a doppler shift in frequency. The frequency of the modulation can result in a change in range, velocity, or combinations of both.

Abstract: A system jointly estimates states of GNSS receivers moving in a region using measurements of a Global Navigation Satellite System (GNSS). The system clusters the GNSS receivers into different clusters subject to a constraint on an upper bound on each cluster and executes a set of probabilistic filters corresponding to the set of clusters to estimate the states of GNSS receivers in each cluster. Each probabilistic filter estimates the states of the GNSS receivers in a corresponding cluster by fusing the GNSS data collected from the GNSS receivers in the cluster to jointly reduce an estimation error of each of the GNSS receivers in the cluster. The DES updates the cluster assignments based on a measure of estimation error in the states of different GNSS receivers in different clusters.

Abstract: An antenna system for a mobile communications base station and a method of operating a communications network including a base station is described. The antenna system includes an antenna array for beamforming and is configured either as a radar sensor, a communications antenna or a combined radar sensor. A radar image may be used to determine a map of objects in the vicinity of the antenna system and to adapt the beam-steering or beamforming of the antenna system.