Abstract: This document describes techniques and systems of a radar system with an angle-finding process for sparse uniform arrays. The described radar system includes a processor and an antenna that can receive electromagnetic energy reflected by objects in the surrounding environment. The antenna includes a one-dimensional (1D) or two-dimensional (2D) sparse array. The processor can determine, using the received electromagnetic energy, a signal subspace associated with the objects that includes an invariance equation. Using an estimated solution to the invariance equation, the processor determines a solution to the invariance equation. The solution to the invariance equation is used to determine angular phases associated with the objects. The processor can then determine, using the angular phases, angles associated with the objects. In this way, the described angle-finding process enables the radar system with a sparse array to efficiently determine angles associated with objects without blind spots.

Abstract: Systems and methods to perform sensor fusion with a depth imager and a radar system involve transmitting radio frequency (RF) energy from the radar system to a region and simultaneously emitting light to the region using a light source, Reflected light is received at a depth imager aligned with the light source, and RF reflections are received at the radar system. The reflected light is processed to obtain azimuth, elevation, range, variance in range, and reflectivity to each pixel that makes up the region. Processing the RF reflections provides azimuth, elevation, range, variance in range, velocity, and variance in velocity to a subset of the pixels representing a region of interest. Performing the sensor fusion includes using the azimuth, the elevation, the variance in range, and the reflectivity resulting from the depth imager and the range, the velocity, and the variance in velocity resulting from the radar system.

Abstract: A vehicle includes a plurality of transmitters of a code division multiple access (CDMA) radar system to simultaneously transmit a frame of transmit signals. A first time duration between transmissions of a first pair of sequential ones of the transmit signals is linearly increased to a second time duration between transmissions of a second pair of sequential ones of the transmit signals. The vehicle also includes a receiver of the CDMA radar system to receive reflected energy resulting from reflection of one of more of the transmit signals of one or more of the plurality of transmitters by an object. A controller processes the reflected energy to obtain information about the object and to control an operation of the vehicle based on the information.

Abstract: A FMCW radar system with a built-in self-test (BIST) system for monitoring includes a receiver, a transmitter, and a frequency synthesizer. A FMCW chirp timing engine controls timing of operations at least one radar component. The BIST system includes at least one switchable coupling for coupling a first plurality of different analog signals including from a first plurality of selected nodes in the receiver or transmitter that are all coupled to a second number of monitor analog-to-digital converters (ADCs). The second number is less than (<) the first plurality of different analog signals. The BIST system includes a monitor timing engine and controller operating synchronously with the chirp timing engine, that includes a software configurable monitoring architecture for generating control signals including for selecting using the switchable coupling which analog signal to forward to the monitor ADC and when the monitor ADC samples the analog signals.

Abstract: Model based inertial navigation for a spinning projectile is provided.

Abstract: According to an aspect of the invention, there is provided a control system for controlling a projectile, the control system comprising: a plurality of transmitters, wherein each transmitter of the plurality of transmitters is arranged to transmit an electromagnetic wave from a transmission position; a receiver associated with the projectile, the receiver being arranged to receive a plurality of electromagnetic waves transmitted from the plurality of transmitters; a controller associated with the projectile, the controller being arranged to: determine at least one of a position, a velocity or an acceleration of the projectile from transmission positions of the plurality of transmitters and Doppler measurements derived from the received plurality of electromagnetic waves; and generate a control signal for performing an action with the projectile depending on the determined at least one of position, velocity or acceleration of the projectile.

Abstract: In a general aspect of the examples described, motion is detected based on bi-directional channel sounding. In an example, a first set of channel information is obtained from a first device. The first set of channel information is based on a first set of wireless signals transmitted from a second device through a space at a first time in a timeframe. A second set of channel information is obtained from the second device. The second set of channel information is based on a second set of wireless signals transmitted from the first device through the space at a second time in the timeframe. The first and second sets of channel information are analyzed to detect a category of motion or a location of detected motion in the space during the timeframe.

Abstract: A simulation system for use in testing a radar system comprises a coarse delay module, a fine delay module, and a doppler shift module. The coarse delay module is configured to receive a first stream of digital data samples that are sampled from a radar signal at a sample time period or a second stream of digital data samples that are processed by another simulation system component and delay the digital data samples by a selectable first delay time that is greater than or equal to the sample time period. The fine delay module is configured to receive the digital data samples and filter the digital data samples to represent delay by a selectable second delay time that is less than the sample time period. The doppler shift module is configured to receive the digital data samples and adjust a value of a frequency content of the fine delayed samples.

Abstract: The present disclosure generally pertains to systems and methods for processing radar signals from a sparse MIMO array. In some embodiments, the signals from a MIMO radar array are processed to generate a sparse virtual array. Then, by using a two-dimensional (2D) variant of missing-data iterative adaptive approach (missing-data IAA or MIAA) to process the virtual array, the system can estimate information from the missing antennas of the sparse virtual array. Then, by using the now full virtually array, the system can process the virtual array using a variant of multi-dimensional folding (MDF) to discover the existence and location (e.g., distance, elevation, and azimuth) of objects (also called scatterers) within the MIMO radar array's field of view.

Abstract: The system and method of projectile flight management using a combination of radio frequency orthogonal interferometry for the long range navigation and guidance of one or more projectiles and a short range navigation and guidance system to provide for more accurate targeting, especially in GPS-denied and GPS-limited environments.

Abstract: The system and method for chromatic correlation interferometry direction finding (CIDF) used to resolve ambiguities. Ambiguities are overcome by correlating over a range of frequencies. In some cases, multiple (i.e., 2 or more) frequencies or a continuous range of frequencies are used to make a more robust correlation manifold. As the complex response manifold is frequency dependent, using a set of two or more manifolds provides a significant reduction of false peaks.

Abstract: The system and method represents a high-resolution, three-dimensional, multi-static precipitation RADAR approach that employs agile microsatellites, in formation and remotely coupled. This system and method uses multi-static RADAR interferometric methods implemented via a microsatellite formation to synthesize an effectively large (e.g., 15 m when using the Ku RF band) aperture to provide about 1 km horizontal resolution and about 125 m vertical resolution.

Abstract: A system and method to aid in guidance, navigation and control of a guided projectile including a precision guidance munition assembly is provided. The system and method obtain raw position data during flight of the guided projectile, the raw position data including a plurality of position data points from the guiding sensor for determining positions of the guided projectile, establish a window including a portion of the plurality of position data points, smooth the portion of the plurality of position data points in the window, and determine a reduced noise position estimate of the guided projectile, based, at least in part, on the smoothed portion of the plurality of position data points in the window. The system and method may determine a velocity estimate of the guided projectile and predict an impact point of the guided projectile relative to a target.

Abstract: Techniques and apparatuses are described for radar angular ambiguity resolution. These techniques enable a target's angular position to be determined from a spatial response that has multiple amplitude peaks. Instead of solely considering which peak has a highest amplitude, the techniques for radar angular ambiguity resolution select a frequency sub-spectrum, or multiple frequency sub-spectrums, that emphasize amplitude or phase differences in the spatial response and analyze an irregular shape of the spatial response across a wide field of view to determine the target's angular position. In this way, each angular position of the target has a unique signature, which the radar system can determine and use to resolve the angular ambiguities. Using these techniques, the radar can have an antenna array element spacing that is greater than half a center wavelength of a reflected radar signal that is used to detect the target.

Abstract: Systems, devices, and methods for a vertical take-off and landing (VTOL) aerial vehicle having a first GPS antenna and a second GPS antenna, where the second GPS antenna is disposed distal from the first GPS antenna; and an aerial vehicle flight controller, where the flight controller is configured to: utilize a GPS antenna signal via the GPS antenna switch from the first GPS antenna or the second GPS antenna; receive a pitch level of the aerial vehicle from the one or more aerial vehicle sensors in vertical flight or horizontal flight; determine if the received pitch level is at a set rotation from vertical or horizontal; and utilize the GPS signal not being utilized via the GPS antenna switch if the determined pitch level is at or above the set rotation.

Abstract: In one embodiment, a method includes identifying, for each of one or more environmental radars, one or more parameter values associated with a radar signal of the environmental radar, determining one or more transmission parameter values for the radar, wherein a combination of the one or more transmission parameter values is different from a combination of the one or more parameter values of each of the one or more environmental radars, and configuring the radar with the determined one or more transmission parameter values.

Abstract: A method for radar imaging is disclosed herein. The method may comprise using a plurality of radar antenna arrays provided on a terrestrial vehicle to obtain phase measurements associated with one or more radar signals transmitted and received by the plurality of radar antenna arrays as the terrestrial vehicle moves through an environment. The method may further comprise processing the phase measurements to compute (i) a set of object-specific properties for one or more objects external to the terrestrial vehicle and (ii) a set of vehicle-specific properties for the terrestrial vehicle. The method may further comprise using the set of object-specific properties and the set of vehicle-specific properties to generate one or more radar images of the environment as the terrestrial vehicle moves through the environment.

Abstract: A distributed FMCW radar communication system for interference mitigation in an ego unit comprising at least one RadCom unit arranged for radar sensing in a radar mode and for data communication in a communication mode with at least one target unit by switching between the radar mode and the communication mode in time and using separate frequency bands for the radar mode and the communication mode, using a random medium access technique for communication, where the ego unit comprises a plurality of RadCom units and a control unit adapted to control the plurality of RadCom units to use different starting times and frequency bands based on at least one received control message by means of communication during a radar frame duration (Tf) received by means of the data communication, where the starting times of different FMCW radars are separated sufficiently so as they are orthogonal.

Abstract: A multicarrier phase ranging system and method are provided. Generally, the method includes performing a handshake between first and a second transceiver to negotiate a list of channels and a start-time for a multicarrier phase ranging process. The process includes in a first cycle exchanging a Constant Tone (CT) between the first and second transceiver in a first epoch on a first channel, and processing the CT received in the first and second transceiver to measure a difference in phase between the CT received and a reference signal. The CT received is checked for interference using software or hardware in either or both of the first and second transceiver. If no interference is detected the first and second transceiver switch to another channel and exchange the CT at a next epoch. If interference is detected, at least one channel is skipped for at least a subsequent epoch.

Abstract: A radar apparatus includes transmitting means, receiving means, target detection means, and a cover member. The cover member is positioned opposite at least one of the transmitting means and the receiving means, such as to cover at least one of the transmitting means and the receiving means. The cover member is provided with a first face which is positioned opposite at least one of the transmitting means and the receiving means, and a second face which is on an opposite side from the first face and is not parallel to the first face.