A radar system includes a transmitter, a receiver and a processor. The receiver receives radio signal that includes the transmitted radio signal reflected from targets in the environment. The received radio signal is provided to the processor. The processor samples the received radio signal during a plurality of time intervals to produce a sampled stream. The different time intervals of the plurality of time intervals will contain different signal levels of radio signals reflected from the targets. The processor also selects a particular time interval of the plurality of time intervals that is free of samples of radio signals reflected off of the targets that are closer than a first threshold distance from an equipped vehicle. The transmitter and/or the receiver is adjusted such that samples of radio signals reflected off of targets that are farther than the first threshold distance are detected.

A method of orthogonal modulation of radar waves of a phase-modulated continuous wave radar system. The method includes selecting an equidistant bi-phased or multi-phased phase-modulation sequence, phase-modulating the continuous radar wave, and transmitting the orthogonal phase-modulated continuous radar wave towards a scene. The method includes generating a detection sequence (s) by applying an outer coding (H) to the phase-modulation sequence, selecting a communication range (C) in the complex number plane, based on the selected phase-modulation, generating a communication sequence (c) having a plurality of sequence members, mapping the communication sequence (c) into the communication range (C) by applying an injective mapping function () to the sequence members, and calculating a numerical product of members of the detection sequence (s) with members of an image of the mapped communication sequence (c). Phase-modulating the continuous wave of the radar system is carried out according to the calculated numerical products.

A method of orthogonal modulation of radar waves of a phase-modulated continuous wave radar system. The method includes selecting an equidistant bi-phased or multi-phased phase-modulation sequence, phase-modulating the continuous radar wave, and transmitting the orthogonal phase-modulated continuous radar wave towards a scene. The method includes generating a detection sequence (s) by applying an outer coding (H) to the phase-modulation sequence, selecting a communication range (C) in the complex number plane, based on the selected phase-modulation, generating a communication sequence (c) having a plurality of sequence members, mapping the communication sequence (c) into the communication range (C) by applying an injective mapping function () to the sequence members, and calculating a numerical product of members of the detection sequence (s) with members of an image of the mapped communication sequence (c). Phase-modulating the continuous wave of the radar system is carried out according to the calculated numerical products.

A method is provided that includes a vehicle receiving data from an external computing device indicative of at least one other vehicle in an environment of the vehicle. The vehicle may include a sensor configured to detect the environment of the vehicle. The at least one other vehicle may include at least one sensor. The method also includes determining a likelihood of interference between the at least one sensor of the at least one other vehicle the sensor of the vehicle. The method also includes initiating an adjustment of the sensor to reduce the likelihood of interference between the sensor of the vehicle and the at least one sensor of the at least one other vehicle responsive to the determination.

A wave transmitted by an antenna made up of an array of radiating elements, two pulse waves are transmitted, each modulated by a phase shift law known as modulation phase shift, the phase shifts being in opposition, a first wave being transmitted by a sub-array of radiating elements referred to as odd and the second wave being transmitted by a second sub-array of radiating elements referred to as even, the two sub-arrays being interleaved, the transmitted wave being the combination of the first wave and the second wave.

In an embodiment, a method of operating a radar includes: generating a set of chirps; transmitting the set of chirps; receiving chirps corresponding to the transmitted set of chirps; using a finite state machine (FSM) to apply a phase shift to each of the transmitted chirps or each of the received chirps based on a code; and demodulating the received chirps based on the code.

A method includes: receiving a ranging signal from the transmitter comprising a set of multiplexed sub-signals, each multiplexed sub-signal characterized by a frequency in a set of frequencies; calculating a time-based time-of-arrival estimate based on the series of time-domain samples of the ranging signal; calculating a time-based uncertainty of the time-based time-of-arrival; for each sub-signal pair in a subset of multiplexed sub-signals of the set of multiplexed sub-signals, extracting a phase difference of the sub-signal pair; calculating a phase-based time-of-arrival estimate based on the phase difference of each sub-signal pair in the subset of multiplexed sub-signals; calculating a phase-based uncertainty of the phase-based time-of-arrival estimate; and calculating a hybrid time-of-arrival estimate as a weighted combination of the time-based time-of-arrival estimate, the phase-based time-of-arrival estimate, based on the time-based uncertainty and the phase-based uncertainty.

A method and apparatus for selecting frequency modulated continuous wave waveform parameters for multiple radar coexistence by a user equipment is described. The user equipment may transmit a radar waveform consisting of a number of chirps, with each chirp having a same duration. The user equipment may vary waveform parameters of the radar waveform for at least a subset of the number of chirp, where the waveform parameters may be chosen from a codebook comprising at least one codeword of parameters. Reflected radar waveforms are received and processed where the processing includes applying a fast time discrete Fourier transform to reflected radar waveforms to produce a one dimension peak in a time delay dimension for each reflected waveform; and applying a slow time discrete Fourier transform to the reflected radar waveforms, where peaks for the reflected waveforms are added.

Methods, systems, and devices for radar signaling are described. In some systems, devices may implement techniques to support coexistence for multiple radar sources using a phase-coded frequency modulated continuous wave waveform. A user equipment (e.g., a vehicle) may select a codeword (e.g., a pattern of parameters) from a codebook and may derive phase code information and waveform shape parameters from values specified in the codeword. The user equipment may apply phase modulation to at least one chirp of a waveform using the indicated phase code. In some cases, the phase-coded frequency modulated continuous wave waveform may resemble nested Zadoff-Chu sequences, where the waveform resembles a Zadoff-Chu sequence and the phase code resembles another Zadoff-Chu sequence. The phase code may support mitigating interference between radar waveforms that use the same slope and frequency offset parameters for chirps overlapping in time.

Non-transitory computer-readable mediums and systems are provided in which a portion of each chirp of a series of chirps is held at an offset frequency for a period of time, and in which the offset frequency, the period of time or both is varied or dithered across the chirps of the series of chirps. The portion of a chirp that is held at an offset frequency for a period of time may be a non-active portion of the chirp, during which the chirp is not sampled. In some implementations, the portion of a chirp that is held at an offset frequency for a period of time is during a falling portion of the chirp, which may be at the beginning of the falling portion, or at the end of the falling portion immediately before a rise portion of a succeeding chirp.