Abstract: Methods, systems, and apparatus, including computer programs encoded on computer-storage media, for positioning a radio signal receiver at a first location within a three dimensional space; positioning a transmitter at a second location within the three dimensional space; transmitting a transmission signal from the transmitter to the radio signal receiver; processing, using a machine-learning network, one or more parameters of the transmission signal received at the radio signal receiver; in response to the processing, obtaining, from the machine-learning network, a prediction corresponding to a direction of arrival of the transmission signal transmitted by the transmitter; computing an error term by comparing the prediction to a set of ground truths; and updating the machine-learning network based on the error term.

Abstract: Techniques are provided for jammer detection. A methodology implementing the techniques according to an embodiment includes estimating an angle of arrival of a jamming signal, the jamming signal included in a received signal, and generating a direction finding (DF) confidence indicator associated with the estimated angle of arrival. The method also includes extracting the jamming signal from the received signal. The method further includes correlating the extracted jamming signal with previously extracted jamming signals to generate a correlation score and using the correlation score as a uniqueness assessment of the extracted jamming signal. The method further includes identifying characteristics of the extracted jamming signal and generating a characterization confidence indicator. The method further includes demoting the extracted jamming signal to non-jammer status based on one or more of the DF confidence indicator, the uniqueness assessment, and the characterization confidence indicator.

Abstract: An electronic device provided by an embodiment of the present invention includes a body, a first, a second and a third array antennas. The body includes a first shell, which has a first and a second sides opposite to each other. The first array antenna is arranged in the first shell and adjacent to the first side, and has a first beam facing a first axis. The second array antenna is arranged in the first shell and adjacent to the second side, and has a second beam facing a second axis. The third array antenna is arranged in the first shell and located between the first and the second array antennas, and has a third beam facing a third axis. The first axis, the second axis and the third axis are different from one another. Accordingly, the electronic device can provide a stable connection quality and a higher transmission rate.

Abstract: An LED taillight with an integrated GPS tracking system is disclosed therein. The GPS tracking system is hidden behind the LED portion of the LED taillight so that the GPS tracking system is not noticeable by someone inspecting a trailer on which the LED taillight is installed. Additionally, power sent to the LED taillight to power the LEDs also recharge a battery associated with the GPS tracking system and power the GPS tracking system during use.

Abstract: The system and method facilitates Real-Time-Kinematic (RTK) GNSS with long baseline between a rover receiver and a base station receiver, even in the presence of scintillation or ionospheric disturbances that spatially fluctuate. Residual atmospheric errors can be estimated by a dual error model in a filter to promote efficient fixing or resolution of carrier phase ambiguities.

Abstract: According to one embodiment, an electronic apparatus includes a processor. The processor is configured to acquire n installation positions where first to n-th pieces of equipment are installed, receive a propagation characteristic related to the first to n-th pieces of equipment, and estimate, by an algorithm, a combination or the first to n-th pieces of equipment and each of the n installation positions based on a propagation characteristic related to the first to n-th pieces of equipment. An initial value of the algorithm is generated based on an arrangement of the n installation positions and an arrangement of the first to n-th pieces of equipment determined based on a propagation characteristic related to the first to n-th pieces of equipment.

Abstract: A reconfigurable sensor network uses continuous-variable (CV) multipartite entangled quantum states for distributed RF sensing with uncertainties below the standard quantum limit. A CV multipartite entangled state is generated with a quantum circuit that splits a squeezed vacuum state into spatially separated optical modes that are entangled. Each optical mode is transmitted to a RF-photonic sensor that imposes, on the corresponding optical mode, a quadrature displacement based on the local properties of an RF signal. A homodyne detector then measures the quadrature displacement. A post-processor combines the measurements to estimate a global property of the RF signal, such as an angle-of-arrival. To enable distributed sensing over large distances, the RF-photonic sensors may be spatially separated by several kilometers, or more. Alternatively, the RF-photonic sensors may be integrated into a single photonic system, such as a photonic integrated circuit.

Abstract: Disclosed are exemplary embodiments of patterned electromagnetic interference (EMI) mitigation materials (e.g., EMI absorbers, thermally-conductive EMI absorbers, etc.) including carbon nanotubes. The carbon nanotubes may comprise single-walled carbon nanotubes, multi-walled carbon nanotubes, and/or carbon nanostructures comprising a branched network of crosslinked carbon nanotube structures. For example, an EMI mitigation material may comprise a filled dielectric including a pattern of EMI absorbers. The filled dielectric comprises carbon nanotubes.

Abstract: This document describes techniques and systems for frequency division multiplexing (FDM) with polyphase shifters. A radar system can include transmitters, receivers, polyphase shifters, and a processor. The transmitters emit electromagnetic (EM) signals in an FDM scheme, and the receivers detect EM signals reflected by objects. The received EM signals include multiple channels. The processor controls the polyphase shifters to introduce phase shifts to the EM signals. The processor can also divide a Doppler-frequency spectrum of the received EM signals into multiple sectors representing a respective frequency range. Each channel is associated with a respective sector. The processor can determine, using non-coherent integration across the sectors, potential detections of the objects, including aliased and actual detections. The processor can then determine the actual detections. In this way, the described FDM techniques with polyphase shifters can resolve Doppler ambiguities in received EM signals.

Abstract: An apparatus for passive coherent location includes a forecaster, an evaluator, a receiver, and a correlator. The forecaster generates a prediction of a radio-frequency signal transmitted from an antenna of a broadcasting service. The evaluator generates an effectiveness metric from the prediction of the radio-frequency signal. The receiver receives the radio-frequency signal that an object reflects from the antenna to the receiver. The correlator determines, from the radio-frequency signal reflected from the object as received at the receiver, an ambiguity function having a maximum at a temporal offset and a Doppler shift. The temporal offset and the Doppler shift at the maximum partially determine at least a position of the object. The apparatus optionally includes a selector for tuning the receiver to the radio-frequency signal in response to the effectiveness metric.

Abstract: A positional sensing system includes a plurality of positional sensing devices which are situated at regular intervals within an environment and collect data for tracking objects moving within the environment. The positional sensing system is used to determine the occupancy and trajectories of people within the environment. The system can determine whether certain areas of the environment need to be cleaned based on occupancy. When a threshold level of use is detected for one or more areas of the environment, the positional sensing system dynamically determines that one or more areas require cleaning, and can generate a cleaning plan for the one or more areas. The positional sensing system can determine an optimal cleaning route through the environment based on the location of one or more areas. Once the cleaning plan is generated, the system can provide the cleaning plan to a user of the positional sensing system for utilization.

Abstract: A circuit comprises a receive processing window formation subsystem, a matched filter subsystem, a keystone interpolation subsystem, a phase modulation subsystem, and an image forming subsystem. The receive processing window formation subsystem forms, for each radar return from a scene, a receive processing window containing the radar return as an unbroken radar return. The matched filter subsystem creates a motion model for a reference point target disposed at a predetermined location within the scene, based on a set of motion compensation parameters for range and range rate, to compensate for at least some effects of fast time Doppler on the reference point target. The keystone interpolation subsystem rescales slow time information from the matched filter subsystem. A phase modulation subsystem applies phase modulations to a keystone-interpolated 2-D output array of information associated with the scene, to ensure proper registration in a range-Doppler map output of the scene.

Abstract: A positional sensing system includes a plurality of positional sensing devices which are situated at regular intervals within an environment and collect data for tracking objects moving within the environment. The positional sensing system is used to determine the occupancy and trajectories of people within the environment. The system can determine whether certain areas of the environment need to be cleaned based on occupancy. When a threshold level of use is detected for one or more areas of the environment, the positional sensing system dynamically determines that one or more areas require cleaning, and can generate a cleaning plan for the one or more areas. The positional sensing system can determine an optimal cleaning route through the environment based on the location of one or more areas. Once the cleaning plan is generated, the system can provide the cleaning plan to a user of the positional sensing system for utilization.

Abstract: Position information estimation in a distributed radio frequency (RF) communications system is provided. Embodiments disclosed herein facilitate high-precision estimations of positions, orientations, velocities, and acceleration of network nodes in a distributed RF network (e.g., including base stations and vehicles, such as aircraft or unmanned aerial systems (UASs)). Modern radio systems must adapt to limited spectral access by reducing spectrum demand and increasing operational efficiency. In this regard, an RF system is provided which simultaneously performs positioning and communications tasks. This system specifically addresses the issue of spectral congestion by employing an extremely efficient positioning strategy and using a joint waveform that simultaneously enables both tasks. This efficiency in turn supports more users in a given frequency allocation.

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: 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: 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: 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: 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 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