A radar system, apparatus, architecture, and method are provided with a transmitter that produces a plurality of distinct FanTOM signals that are transmitted as N RF-encoded transmit signals in an overlapped fashion such that the pulse repetition interval and frame length are kept short; a receiver that processes target return signals reflected from the N RF-encoded transmit signals with a mixer to produce an IF signal which is filtered with one or more notch filters clocked with a sampling clock frequency to control harmonic notch frequencies to suppress transmitter spill-over and close-in self-clutter interference, thereby producing a filtered IF signal that is converted to a digital signal with an analog-to-digital converter that is clocked with the sampling clock frequency; and a radar processor that processes the digital signal to generate a range spectrum comprising N segments that correspond, respectively, to the N RF-encoded transmit signals.

A vehicle radar sensor utilizes Frequency Modulated Continuous Wave (FMCW) radar signals that incorporate non-uniform FMCW chirps having chirp profiles that differ from one another to sense one or more parameters of one or more objects in a field of view of the radar sensor. The chirp profiles may differ from one another in various manners, e.g., based on starting frequency, repetition interval, duration and/or slope, and among other advantages, may be used to enhance sensing of various parameters such as range, Doppler/velocity and/or angle.

A vehicle radar sensor utilizes Frequency Modulated Continuous Wave (FMCW) radar signals that incorporate non-uniform FMCW chirps having chirp profiles that differ from one another to sense one or more parameters of one or more objects in a field of view of the radar sensor. The chirp profiles may differ from one another in various manners, e.g., based on starting frequency, repetition interval, duration and/or slope, and among other advantages, may be used to enhance sensing of various parameters such as range, Doppler/velocity and/or angle.

A multiple-input multiple-output (MIMO) radar system, including: a plurality of transmit channels configured to sequentially transmit signals with transmit-channel-designated Doppler division multiplexing (DDM) modulations; and processing circuitry configured to: determine, for each of the transmit channels, an impulse response of phase modulation errors due to DDM coupling of the respective transmit channel from each of the other transmit channels; and generate, based on the impulse response, a reconstruction matrix of modulation DDM coupling factors.

Techniques are discussed herein for analyzing radar data to determine that radar noise from one or more target detections potentially conceals additional objects near the target detection. Determining whether an object may be concealed can be based at least in part on a radar noise level based on a target detection, as well as distributions of radar cross sections and/or doppler data associated with particular object types. For a location near a target detection, a radar system may determine estimated noise levels, and compare the estimated noise levels to radar cross section probabilities associated with object types to determine the likelihood that an object of the object type could be concealed at the location. Based on the analysis, the system may determine a vehicle trajectory or otherwise may control a vehicle based on the likelihood that an object may be concealed at the location.

Various embodiments include methods and systems having detection apparatus operable to cancel or reduce leakage signal originating from a source signal being generated and transmitted from a transmitter. A leakage cancellation signal can be generated digitally, converted to an analog signal, and then subtracted in the analog domain from a received signal to provide a leakage-reduced signal for use in detection and analysis of objects. A digital cancellation signal may be generated by generating a cancellation signal in the frequency domain and converting it to the time domain. Optionally, an estimate of a residual leakage signal can be generated and applied to reduce residual leakage remaining in the leakage-reduced signal. Additional apparatus, systems, and methods can be implemented in a variety of applications.

Various embodiments include methods and systems having detection apparatus operable to cancel or reduce leakage signal originating from a source signal being generated and transmitted from a transmitter. A leakage cancellation signal can be generated digitally, converted to an analog signal, and then subtracted in the analog domain from a received signal to provide a leakage-reduced signal for use in detection and analysis of objects. A digital cancellation signal may be generated by generating a cancellation signal in the frequency domain and converting it to the time domain. Optionally, an estimate of a residual leakage signal can be generated and applied to reduce residual leakage remaining in the leakage-reduced signal. Additional apparatus, systems, and methods can be implemented in a variety of applications.

A system for compensating for phase noise, with particular application in lidar, includes a compensation interferometer that receives a signal from a source, and splits it into a first and second path, with a path length difference Δτ between them. Typically the path length is significantly less than that of the return distance to a target. The output of the compensation interferometer, which consists of phase noise generated in time Δτ is vectorially summed during a time similar to a signal flight time to a target, and the result used to reduce phase noise present on measurements of a target. It further includes means for selecting Δτ such that competing noise elements are reduced or optimised.

Techniques and apparatuses are described that enable full-duplex operation for radar sensing using a wireless communication chipset. A controller initializes or controls connections between one or more transceivers and antennas in the wireless communication chipset. This enables the wireless communication chipset to be used as a continuous-wave radar or a pulse-Doppler radar. By utilizing these techniques, the wireless communication chipset can be re-purposed or used for wireless communication or radar sensing.

A single frequency, or very narrow frequency band, microwave imaging system is described herein. A microwave imaging system can include an array transmitter; an array receiver; and a computing device that receives signals detected from the array receiver, transforms the signals received by the array receiver into independent spatial measurements, constructs an image using the independent spatial measurements, and outputs a reconstructed image. The array transmitter and the array receiver may each have a plurality of independently controllable metasurface resonant elements.