A multichannel radar system comprising a set of antennas each receiving a sequence of chirps reflected from plurality of objects, a range detector generating a set of range bins for each chirp, a beam former operative to generate a set of dominant frequency components from a group of range bins picked from the set of range bins across the set of antennas, a nearness detector for separating the set of dominant frequencies into a first set of dominant frequencies and a second set of dominant frequencies, a frequency subtractor configured to shift the each dominant frequency in the first set of dominant frequencies by its phase by a first value to form a third set of phase shifted dominant frequencies, and a Doppler estimator estimating a Doppler frequency of the each dominant frequency in the set of dominant frequencies from the third set of phase shifted dominant frequencies and the second set of dominant frequencies.

System and methods are provided which involve a radar system that includes one or more signal generators configured for generating a composite radar waveform formed by combining different component waveforms; and a detector for detecting reflected signals from the composite waveform and determining velocity and distance measurements of a target relative to a host vehicle. Advantageously, the first and second component waveforms are selected such that the composite waveform is able to meet two different sets of resolution requirements with respect to at least one of: (i) the velocity measurement of the target vehicle relative to the host vehicle and (ii) the distance measurement of a target vehicle relative to the host vehicle. Notably, each of the different sets of resolution requirements is pre-selected based on a different type of detection scenario.

System and methods are provided which involve a radar system that includes one or more signal generators configured for generating a composite radar waveform formed by combining different component waveforms; and a detector for detecting reflected signals from the composite waveform and determining velocity and distance measurements of a target relative to a host vehicle. Advantageously, the first and second component waveforms are selected such that the composite waveform is able to meet two different sets of resolution requirements with respect to at least one of: (i) the velocity measurement of the target vehicle relative to the host vehicle and (ii) the distance measurement of a target vehicle relative to the host vehicle. Notably, each of the different sets of resolution requirements is pre-selected based on a different type of detection scenario.

A method for measuring, using a radar or sonar, the velocity with respect to the ground of a carrier moving parallel to the ground, includes the following steps: a) orienting the line of sight of the radar or sonar toward the ground; b) emitting a plurality of radar or sonar signals (P.sub.1-P.sub.N) that are directed toward the ground, and acquiring respective echo signals (E.sub.1-E.sub.N); c) processing the acquired echo signals so as to obtain, for one or more echo delay values, a corresponding Doppler spectrum; d) for the or at least one the echo delay value, determining a high cut-off frequency of the corresponding Doppler spectrum; and e) computing the velocity of the carrier with respect to the ground on the basis of the one or more high cut-off frequencies. A system allowing such a method to be implemented.

A radar sensing system for a vehicle has multiple transmitters and receivers on a vehicle. The transmitters are configured to transmit radio signals which are reflected off of objects in the environment. There are one or more receivers that receive the reflected radio signals. Each receiver has an antenna, a radio frequency front end, an analog-to-digital converter (ADC), and a digital signal processor. The transmitted signals are based on spreading codes generated by a programmable code generation unit. The receiver also makes use of the spreading codes generated by the programmable code generation unit. The programmable code generation unit is configured to selectively generate particular spreading codes that have desired properties.

A radar sensing system for a vehicle has multiple transmitters and receivers on a vehicle. The transmitters are configured to transmit radio signals which are reflected off of objects in the environment. There are one or more receivers that receive the reflected radio signals. Each receiver has an antenna, a radio frequency front end, an analog-to-digital converter (ADC), and a digital signal processor. The transmitted signals are based on spreading codes generated by a programmable code generation unit. The receiver also makes use of the spreading codes generated by the programmable code generation unit. The programmable code generation unit is configured to selectively generate particular spreading codes that have desired properties.

An automated vehicle radar system capable of self-calibration includes an antenna, a transceiver, and a controller. The antenna broadcasts a radar-signal and detects a reflected-signal reflected by an object. The transceiver determines a distance, an angle, and a range-rate of the object relative to the antenna based on the radar-signal and the reflected-signal. The controller determines a speed of a host-vehicle; determines when the object is stationary based on the speed, the angle, and the range-rate; stores in a memory a plurality of detections that correspond to multiple instances of the distance, the angle, and the range-rate as the host-vehicle travels by the object; selects an ideal-response of angle versus range-rate based on the speed; determines a calibration-matrix of the system based on a difference between the plurality of detections and the ideal-response; and adjusts an indicated-angle to a subsequent-object in accordance with the calibration-matrix.

An automated vehicle radar system capable of self-calibration includes an antenna, a transceiver, and a controller. The antenna broadcasts a radar-signal and detects a reflected-signal reflected by an object. The transceiver determines a distance, an angle, and a range-rate of the object relative to the antenna based on the radar-signal and the reflected-signal. The controller determines a speed of a host-vehicle; determines when the object is stationary based on the speed, the angle, and the range-rate; stores in a memory a plurality of detections that correspond to multiple instances of the distance, the angle, and the range-rate as the host-vehicle travels by the object; selects an ideal-response of angle versus range-rate based on the speed; determines a calibration-matrix of the system based on a difference between the plurality of detections and the ideal-response; and adjusts an indicated-angle to a subsequent-object in accordance with the calibration-matrix.

An apparatus for resolving velocity ambiguity in a MIMO RADAR includes a plurality of transmit channels and a virtual channel Each transmit channel includes a transmit antenna configured to transmit a plurality of chirps. Each chirp includes a frequency ramp of a transmit frequency of the respective transmit channel. Each transmit channel is orthogonal to another transmit channel and to a virtual transmit channel. A waveform generator is configured to generate a local oscillator (LO) signal for each transmit channel. A frequency offset circuit is configured to modify the LO signal of each transmit channel with a respective frequency offset to generate the respective transmit frequency.

An apparatus for resolving velocity ambiguity in a MIMO RADAR includes a plurality of transmit channels and a virtual channel Each transmit channel includes a transmit antenna configured to transmit a plurality of chirps. Each chirp includes a frequency ramp of a transmit frequency of the respective transmit channel. Each transmit channel is orthogonal to another transmit channel and to a virtual transmit channel. A waveform generator is configured to generate a local oscillator (LO) signal for each transmit channel. A frequency offset circuit is configured to modify the LO signal of each transmit channel with a respective frequency offset to generate the respective transmit frequency.