A radar system may include a set of analog components to perform one or more radio frequency (RF) operations during an active radar phase of the radar system. The radar system may include a set of digital components to perform one or more digital processing operations during at least a digital processing phase of the radar system. The one or more digital processing operations may be performed such that performance of the one or more digital processing operations does not overlap performance of a substantive portion of the one or more RF operations.

Systems, methods, and computer-readable media are described for combining digital and analog beamsteering in a channelized antenna array. In some examples, a method can include receiving one or more signals at each of a plurality of groups of antenna elements, each group of antenna elements defining a respective channel from a plurality of channels, and steering, by each respective channel and using analog steering, the one or more signals in a respective direction to yield a steered analog signal pattern. The method can further include converting the steered analog signal pattern associated with each respective channel into a respective digital signal and, based on the respective digital signal, generating, using digital steering, digital signal patterns steered within the steered analog signal pattern associated with the respective digital signal.

A novel and useful radar sensor incorporating detection, mitigation and avoidance of mutual interference from nearby automotive radars. The normally constant start frequency sequence for linear large bandwidth FMCW chirps is replaced by a sequence of lower bandwidth chirps with start frequencies spanning the wider bandwidth and randomly ordered in time to create a pseudo random chirp hopping sequence. The reflected wave signal received is reassembled using the known hop sequence. To mitigate interference, the signal received is used to estimate collisions with other radar signals. If detected, a constraint is applied to the randomization of the chirps. The chirp hopping sequence is altered so chirps do not interfere with the interfering radar's chirps. Offending chirps are re-randomized, dropped altogether or the starting frequency of another non-offending chirp is reused. Windowed blanking is used to zero the portion of the received chirp corrupted with the interfering radar's chirp signal.

A radar calibration system is for being disposed on a vehicle. The radar calibration system includes a sensing unit and a housing. The sensing unit includes a receiving antenna array, which includes at least four receiving antennas. The receiving antennas are arranged on an antenna plane and have a receiving antenna center. A distance between the receiving antenna center and a ground plane is greater than 40 cm. The receiving antennas are arranged asymmetrically with respect to the receiving antenna center. The housing includes a bottom surface, which is attached on an outer surface of the vehicle. The sensing unit is disposed in the housing. An antenna plane angle between the antenna plane and the outer surface of the vehicle is in a range of 0 degrees to 90 degrees.

An airborne radar system and signal interpretation approach that detects slow moving ground targets using angle and Doppler of Keystone formatting process, and is referred to as Angle-Doppler Keystone Formatting (ADK). ADK collapses the clutter ridge to a constant Doppler or to a constant angle, thereby transforming a clutter ridge in angle-Doppler space into a horizontal line of constant Doppler or a vertical line of constant angle. Clutter may then be filtered more effectively, such as by using multiple beams as the source of STAP training data or by using multiple Doppler bins.

An ultrasonic imaging apparatus includes a plurality of transducers that transmit ultrasonic waves and a transmission unit that supplies drive signals to the plurality of transducers. An amplitude control voltage generation unit and a transmission circuit unit are connected to a common voltage power supply. An amplitude control voltage generation unit receives an output voltage of the voltage power supply and an attenuation degree setting signal instructing an attenuation degree of the drive signal for each of the transducers for weighting of the drive signal, and generates an amplitude control voltage corresponding to a voltage obtained by attenuating the output voltage by the attenuation degree. The output voltage of the voltage power supply is reduced to a voltage corresponding to the amplitude control voltage, and a drive signal having a predetermined waveform is generated whose amplitude is the voltage after the reduction for each of the transducers.

A method for increasing the effective aperture of radar switch/MIMO antenna array, using a low number of transmit (Tx) and receive (Rx) army elements, according to which an array of radar physical receive (Rx)/Transmit (Tx) elements are arranged in at least two opposing Rx rows and at least two opposing Tx columns, such that each row includes a plurality of receive (Rx) elements uniformly spaced from each other and each column includes a plurality of transmit (Tx) elements uniformly spaced from each other, the array forming a rectangular physical aperture. Used as a switch array, a first Tx element from one column is activated to transmit a radar pulse during a predetermined time slot. Reflections of the first transmission are received in all Rx elements, thereby virtually replicating the two opposing Rx rows about an origin determined by the location of the first Tx element within the rectangular physical aperture. This process is repeated for all remaining Tx elements during different time slots, thereby virtually replicating the two opposing Rx rows about an origin determined by the location of each activated Tx element within the rectangular physical aperture, while each time, receiving reflections of the transmission from each Tx element in all Rx elements. This way, a rectangular virtual aperture having dimensions which are twice the dimensions of the rectangular physical aperture is paved with replicated two opposing Rx rows. This virtual aperture determines the radar beam widths and side-lobes.

A radar apparatus and an interference suppression method are provided. The radar apparatus includes a clock generator, an analog to digital converter (ADC), and a notch filter. The clock generator is configured to generate a sampling frequency. The ADC is coupled to the clock generator, and is configured to convert an analog signal into a digital signal according to the sampling frequency. The notch filter is coupled to the ADC, and is configured to attenuate one or more interfered frequencies of the digital signal. The interfered frequencies are related to the sampling frequency. Accordingly, the interference at a specific frequency and harmonics thereof may be suppressed.

For example, a radar apparatus may include an input to receive radar receive (Rx) data, the radar Rx data based on radar signals received via a plurality of Rx antennas of Multiple-Input-Multiple-Output (MIMO) radar antenna; and a radar processor configured to generate radar information based on the radar Rx data by calibrating an antenna Mismatch (MM) of the MIMO radar antenna such that the radar information includes an Angle of Arrival (AoA) spectrum having a Peak Side Lobe Level (PSLL) of at least 30 decibel (dB).

Disclosed is a method and apparatus for generating a radar signal, in which performance of radar detection is ensured while increasing a spectrum efficiency in a radar network. The method comprises generating a set of frequency-modulation waveforms, generating an orthogonal code set, generating a set of coded frequency-modulation waveforms through element operation between the set of frequency-modulation waveforms and the orthogonal code set, calculating an objective function for the set of frequency-modulation waveforms with regard to a different set of coded frequency-modulation waveforms and previous sets of coded frequency-modulation waveforms, and selecting a current polyphase code set as an optimized polyphase code set when a result of current calculation is better or smaller than a result of previous iteration, and performing phase perturbation by replacing an element randomly selected in the current polyphase code set selected as the optimized polyphase code set with another admissible-phase element.