Abstract: An apparatus configured to: receive an input dataset indicative of the amplitude and phase of radar signals received at a plurality of antenna elements; determine an objective function; determine a beam forming spectrum, the beam forming spectrum comprising a correlation of the input dataset with a set of beamsteering vectors; perform a first determination process for evaluation of the objective function comprising the processor being configured to: identify two or more peaks in the beam forming spectrum based on a predetermined threshold level, determine candidate direction-of-arrival angles therefrom for definition of a first-reduced search space; perform a second determination process for evaluation of the objective function comprising the processor being configured to: determine a peak direction-of-arrival angle comprising the direction-of-arrival angle that corresponds to a peak in the beam forming spectrum: evaluate the objective function over the first reduced search space and using the peak d

Abstract: Aspects of the present disclosure are directed to radar apparatuses and methods involving the communication of data with radar signals. As may be implemented with one or more embodiments, a sequence of radar waveforms are transmitted as RF signals, the RF signals carrying communication data encoded onto a ramped radar carrier signal via phase-shift keying (PSK) modulation. Such modulation may utilize a modified, reduced-angle modulation with phase angles of less than ?. Object-reflected versions of the RF signals are received and demodulated by deramping the received object-reflected versions of RF signals using a linearized version of the radar waveforms (e.g., without PSK modulation). This approach can mitigate compression peak loss.

Abstract: In imaging radar, examples are directed to uses of multiple sets of transmit antenna included with transceiver circuitry, for transmitting in a plurality of modes. Transmissions may involve having at least one transmit antenna, from each of at least two of the multiple sets, to transmit continuous-wave energy concurrently (simultaneously) in one or more of the plurality of different modes. Transceiver circuitry may include multiple receive antennas which may be receiving reflections of the continuous-wave energy from various targets. Signals from the multiple receive antennas may route to signal processing circuitry. The signal processing circuitry may respond to the received reflections of the continuous-wave energy by assessing differences in antenna gain and/or phase due to transmit antenna position associated with the received reflections.

Abstract: In accordance with a first aspect of the present disclosure, a radar system is provided, comprising: a plurality of receive channels; a first radar detector stage configured to detect, through said receive channels, at least one target using a detector threshold; a noise correlation determination unit configured to determine a noise correlation level indicative of noise correlation between the receive channels if the first radar detector stage has detected the target; a detector threshold adjustment unit configured to adjust the detector threshold in dependence on the noise correlation level determined by the noise correlation determination unit; a second radar detector stage configured to detect the target using the adjusted detector threshold. In accordance with a second aspect of the present disclosure, a corresponding method of operating a radar system is conceived.

Abstract: A data processing device and method for detecting interference in FMCW radar signals, configured to use an adaptive thresholding technique to identify interference in a plurality of samples forming a beat signal, the adaptive thresholding including grouping the plurality of samples into a plurality of subsets, determining a maximum magnitude of each subset and extracting an nth lowest maximum magnitude of the plurality of subsets to determine an adaptive threshold, and applying the adaptive threshold to each sample to generate a mask.

Abstract: An apparatus configured to receive an input dataset, x, indicative of radar signals reflected from targets as received at a plurality of antenna elements; define a matrix, A, formed of direction-of-arrival-angle vectors, an, each direction-of-arrival-angle vector representing an expected response at the plurality of antenna elements of radar signals from one of the targets; define a signal amplitude vector s to represent expected complex amplitudes as received in the radar signals; define an objective function based on x, A and s; search for a set of direction of arrival angles for each of the plurality of targets by the repeated evaluation of the objective function for a plurality of candidate matrices based on matrix A; and wherein said search space comprises a plurality of discrete points, z, associated with the direction of arrival angles by a function of sin(?k).

Abstract: A method of processing radar signalling, the method comprising: receiving a mask (815) that represents samples in the radar signalling that are detected as including interference. The mask (815) comprises a matrix of data having a first dimension and a second dimension, wherein the first dimension represents a fast-time axis and the second dimension represents a slow-time axis. The method further comprises performing frequency analysis on the mask (815) across each of the fast-time axis and the slow-time axis of the mask in order to provide a range-Doppler processed mask (817); and deconvolving a range-Doppler map (813) of the received radar signalling using the range-Doppler processed mask (817) in order to provide a deconvolved-range-Doppler map (814).

Abstract: A mechanism is provided for determining an unambiguous direction of arrival (DoA) for radio frequency (RF) signals received by a sparse array. A DoA angle domain is split into hypothesis regions. The hypothesis regions are derived from the phase differences of the antenna element pairs used for the DoA angle estimate. In each hypothesis region, the ambiguous phase of antenna element pairs is unwrapped according to expected wrap-around. After unwrapping the phase, for each hypothesis region, a phasor is calculated by combining the individual antenna element pair phasors. The hypothesis region that obtains the phasor with a largest amplitude is selected as the most likely DoA region and the phase of the winning phasor is used as an unambiguous estimate for the DoA angle.

Abstract: A radar system is disclosed that provides joint object detection and communication capabilities. The radar system includes a communication signal generator that provides a communication signal, a pre-distortion module that applies a pre-distortion to the communication signal to provide a pre-distorted communication signal, a linear frequency modulation (LFM) signal generator that provides a LFM signal, and a mixer that mixes the pre-distorted communication signal onto the LFM signal to provide a radar signal to be transmitted by the radar system. The radar system further includes an all-pass filter that filters a plurality of de-ramped reflected images of the radar signal to provide a filtered signal. Each de-ramped reflected image includes an associated image of the pre-distorted communication signal. The all-pass filter provides a linear group delay, and a non-linear phase response. The pre-distortion is an inverse of the non-linear phase response of the all-pass filter.

Abstract: Embodiments are directed to a method for determining velocity of an object. The method includes in response to two interleaved chirp sequences being sent towards the object, processing responsive chirps of each of the two interleaved chirp sequences independently from one another to produce respective Doppler-spectrum data sets, and calculating the velocity of the object based on the respective Doppler-spectrum data sets. Each of the interleaved chirp sequences being characterized by a common time spacing between respective chirps of the respective chirp sequence, and each chirp of one of the chirp sequences being offset by an amount of time that is different than the common time spacing.

Abstract: A mechanism is provided for determining an unambiguous direction of arrival (DoA) for radio frequency (RF) signals received by a sparse array. A DoA angle domain is split into hypothesis regions. The hypothesis regions are derived from the phase differences of the antenna element pairs used for the DoA angle estimate. In each hypothesis region, the ambiguous phase of antenna element pairs is unwrapped according to expected wrap-around. After unwrapping the phase, for each hypothesis region, a phasor is calculated by combining the individual antenna element pair phasors. The hypothesis region that obtains the phasor with a largest amplitude is selected as the most likely DoA region and the phase of the winning phasor is used as an unambiguous estimate for the DoA angle.

Abstract: A data processing device and method for detecting interference in a FMCW radar system are described. For each of a plurality of transmitted chirps of the radar system, a high pass filter is applied to a receiver signal of a receiver channel of a radar receiver during an acquisition time corresponding to a transmitted chirp to remove those parts of the receiver signal corresponding to a reflected chirp having a power at the radar receiver greater than the noise power of the radar receiver of the radar system. The receiver signal power is calculated from the high pass filtered receiver signal. The receiver signal power is compared with a threshold noise power based on an estimate of the thermal noise of the radar receiver to determine whether the receiver signal corresponds to an interfered received chirp including interference or a non-interfered received chirp not including interference.

Abstract: A mechanism is provided to determine if a short-range automotive radar detection is a direct reflection or an indirect (also known as “multipath”) reflection from a physical target object. The multipath information is further used to perform a height estimation of the object. Embodiments provide a radar system having a range resolution smaller than a path difference between the direct reflection path and the indirect reflection path. Both range separation techniques and Doppler separation techniques are utilized to provide a reliable and accurate estimation of the height of the object.

Abstract: In imaging radar, examples are directed to uses of multiple sets of transmit antenna included with transceiver circuitry, for transmitting in a plurality of modes. Transmissions may involve having at least one transmit antenna, from each of at least two of the multiple sets, to transmit continuous-wave energy concurrently (simultaneously) in one or more of the plurality of different modes. Transceiver circuitry may include multiple receive antennas which may be receiving reflections of the continuous-wave energy from various targets. Signals from the multiple receive antennas may route to signal processing circuitry. The signal processing circuitry may respond to the received reflections of the continuous-wave energy by assessing differences in antenna gain and/or phase due to transmit antenna position associated with the received reflections.

Abstract: Aspects of the present disclosure are directed to a method and/or apparatus involving frequency modulated continuous wave (FMCW) radar signals. As my be implemented in accordance with one or more embodiments, receiver circuitry is configured and arranged to receive a FMCW radar signal having an information signal embedded into a radar waveform, and to indicate a relationship in the FMCW radar signal between beat frequency magnitude and time delay. A filter processing circuit is configured and arranged to filter the information signal in the FMCW radar signal by applying a group delay function based on the relationship between beat frequency magnitude and time delay. Signal processing circuitry is configured and arranged to detect a remote object by using the filtered FMCW radar signal.

Abstract: A radar system is disclosed that provides joint object detection and communication capabilities. The radar system includes a communication signal generator that provides a communication signal, a pre-distortion module that applies a pre-distortion to the communication signal to provide a pre-distorted communication signal, a linear frequency modulation (LFM) signal generator that provides a LFM signal, and a mixer that mixes the pre-distorted communication signal onto the LFM signal to provide a radar signal to be transmitted by the radar system. The radar system further includes an all-pass filter that filters a plurality of de-ramped reflected images of the radar signal to provide a filtered signal. Each de-ramped reflected image includes an associated image of the pre-distorted communication signal. The all-pass filter provides a linear group delay, and a non-linear phase response. The pre-distortion is an inverse of the non-linear phase response of the all-pass filter.

Abstract: Embodiments are directed to a method for determining velocity of an object. The method includes in response to two interleaved chirp sequences being sent towards the object, processing responsive chirps of each of the two interleaved chirp sequences independently from one another to produce respective Doppler-spectrum data sets, and calculating the velocity of the object based on the respective Doppler-spectrum data sets. Each of the interleaved chirp sequences being characterized by a common time spacing between respective chirps of the respective chirp sequence, and each chirp of one of the chirp sequences being offset by an amount of time that is different than the common time spacing.

Abstract: A signal generator for a phased array antenna comprises a laser light source arranged to provide an optical spectrum comprising a plurality of spaced wavelengths. The signal generator further comprises a dispersion unit arranged to introduce a delay to a plurality of spectral components of the optical spectrum associated with the spaced wavelengths. The delay is dependent on the wavelength of the spectral components of the optical spectrum. The signal generator further comprises a heterodyning device configured to generate a signal for the phased array antenna by heterodyning the spectral components associated with different ones of the spaced wavelengths of the laser light source.

Abstract: A periodic phase modulation, having a period shorter than a symbol period, is applied as a source modulation, in addition to a symbol modulation, to signals transmitted between a transmitter and a receiver in a communication network. Symbol value elements can be sent from multiple transmitters (203, 303, 603, 703) to a receiver (607, 207) in the same symbol period can be processed on the basis of the source modulation without destructive interference. In some embodiments, the symbol value elements sent by different transmitters can be combined in the receiver. In some embodiments, symbol value elements sent by different transmitters can be distinguished in the receiver.

Abstract: Disclosed is a digital signal processing unit, for a frequency modulated continuous wave, FMCW, radar receiver module and configured to receive a digital in-phase signal and a digital quadrature signal and to provide an interference-suppressed signal, wherein the digital signal processing unit comprises: a processing subunit, configured to provide an an-band intermediate frequency, IF, signal and an image-band IF signal; an image-band processing unit configured to identify an interference window, estimate an interference crossing moment, and mirror the image band IF signal across the interference window about the interference crossing moment; and combinatorial logic configured to subtract the mirrored signal from the in-band IF signal.