Aspects of the present disclosure are directed to radar signal processing apparatuses and methods. As may be implemented in accordance with one or more embodiments, digital signals representative of received reflections of radar signals transmitted towards a target are mathematically processed to provide or construct a matrix pencil based on or as a function of a forward-backward matrix. Eigenvalues of the matrix pencil are computed and an estimation of the direction of arrival (DoA) of the target is output based on the computed eigenvalues.

A frequency modulation continuous wave (FMCW)-based system configured to convert measurements of a linearly modulated wave from a time-domain into a frequency-domain to produce a non-linear frequency signal, where the non-linear frequency signal comprises a known linear component representing the desired linear modulation and an unknown non-linear component representing the non-linearity of the modulation. The FMCW-based system is further configured to determine coefficients of a basis function approximating a difference between the non-linear frequency signal and the linear frequency component in the frequency domain. The FMCW-based system is further configured to detect one or multiple spectrum peaks in the distorted beat signal with the distortion compensated according to the basis function with the determined coefficients to determine one or multiple distances to the one or multiple objects in the scene.

An apparatus is disclosed for multiplexing radar beat signals. In an example aspect, the apparatus includes an antenna array and a wireless transceiver jointly configured to transmit a radar transmit signal and receive two or more radar receive signals. The two or more radar receive signals represent portions of the radar transmit signal that are reflected by an object. The wireless transceiver comprises a radio-frequency integrated circuit with two or more receive chains and a multiplexing circuit. Each one of the two or more receive chains is configured to generate a radar beat signal by downconverting a respective radar receive signal of the two or more radar receive signals using the radar transmit signal. The multiplexing circuit is coupled to the two or more receive chains and is configured to multiplex the two or more radar beat signals together to generate a composite radar beat signal.

Data memory protection is provided for a signal processing system such as a radar system in which the data memory is protected with a common set of parity bits rather than requiring a set of parity bits for each memory word as in Error Correction Coded (ECC) memories. The common set of parity bits may be updated as memory words in the data memory are accessed as part of signal processing of one or more digital signals. The memory protection ensures that in the absence of memory errors the common parity bits are zero at the end of processing the digital signals as long as each word in the data memory that is used for storing the signal processing data is written and read an equal number of times.

A method is described below which can be used in a radar system. According to one example implementation, the method comprises providing a digital baseband signal using a radar receiver. The baseband signal comprises a plurality of segments, wherein each segment is assigned to a chirp of an emitted chirp sequence and each segment comprises a specific number of samples. For each signal sequence of n samples of the segments, where n in each case denotes a specific sample position within the respective segment, the method comprises the following: detecting interference-affected samples of the signal sequence; splitting the signal sequence into two or more sub-band signal sequences, wherein each sub-band signal sequence is assigned in each case to a frequency sub-band; replacing interference-affected samples in the two or more sub-band signal sequences in each case with a value which is based on adjacent samples in order to obtain corrected sub-band signal sequences; and determining a corrected signal sequence of n samples of the segments based on the corrected sub-band signal sequences.

A video recording and communication device includes a camera, a processor, a radar sensor, and memory. The processor executes instructions from memory to cause the device to operate the sensor in a first operational mode in which the camera is maintained in a low-power mode. The processor further detects, using the sensor in the first mode, possible motion of an object within a threshold distance from the sensor. Responsive to the detecting, the processor transitions the sensor from the first mode to a second operational mode. The second mode consumes more power than the first mode. The processor determines, using the radar sensor in the second mode, that the possible motion of the object occurred in a region of interest, in response to which, it transitions the sensor from the second mode to a third operational mode. The third mode consumes more power mode than the second mode.

An image forming apparatus has a photosensitive drum configured to bear a developer image, a developing apparatus having a developing roller that bears developer and a developing blade that regulates the amount of the developer on the developing roller, and a detection portion that detects information on the amount of the developer stored in the developing apparatus. The image forming apparatus performs a discharging operation for discharging a coating agent, applied to a developing roller in an unused state, from the developing apparatus to the photosensitive drum, while varying an operational condition for the discharging operation varied based on the information.

A MIMO radar system including a transmitter array, and a receiver array, the antenna distances in one of the transmitter and receiver arrays being above the Nyquist limit for unambiguous angle measurements, but the antenna distances in the combination of the transmitter and receiver arrays being below this Nyquist limit. The system also includes a control and evaluation unit.

A radar including an interface configured to receive a frequency estimation output and a synchronization signal correlation output from a radio communication device; and a processing block configured to use the received frequency estimation output and synchronization signal correlation output for velocity and range estimation.

A radar system includes a radar transceiver device, which includes a transmitter front end circuit for transmitting a chirp signal towards an object. The radar transceiver device includes a receiver front end circuit for receiving the reflected chirp signal from the object. The radar transceiver device includes a voltage controlled oscillator (VCO) to generate a transmitted chirp signal. The radar transceiver device includes a mixer configured to generate four intermediate frequency output signals having different phases. The radar system includes a controller device, which includes a processor, and a memory for storing the intermediate frequency output signals and instructions for executing in the processor. The instructions cause the processor to generate a complex Fast Fourier Transform (FFT) result by performing a FFT of the intermediate frequency output signals while using zero-padding. The instructions cause the processor to determine, using interpolation, a maximum amplitude in the FFT result and identifying the frequency corresponding to the maximum amplitude. The instructions cause the processor to calculate a distance to the object using the determined frequency.