The invention relates to a method for filtering a numerical input signal sampled at a sampling frequency in order to obtain a filtered signal, the method including at least one step for: obtaining a first (respectively second) output signal by carrying out first (respectively second) operations on the first (respectively second) processing channel, the first (respectively second) operations including at least the application of a discrete Fourier transform to M/2.sup.p points on a signal coming from the input signal, the integer p being greater than or equal to 1, applying an inverse discrete Fourier transform to M/2.sup.p points on the first signal in order to obtain M points of the spectrum of the first signal, M being an integer strictly greater than 2, the application step being carried out by the addition of the results of two processing channels.

Provided is a radar apparatus including: an estimation circuit; and a processing circuit. The estimation circuit outputs a plurality of pieces of data each including information in which a distance to a target and a direction to the target are estimated based on a reception signal including a reflected wave that is a radar signal reflected by the target. The processing circuit determines a range side lobe component in the target based on the estimated distance and the estimated direction of one or more pieces of data selected from the plurality of pieces of data.

A radar device includes a suppression band variable filter that, while a circulator outputs any one transmission signal out of a plurality of transmission signals to an antenna, and the antenna transmits the transmission signal, suppresses a signal of the same frequency channel as a frequency channel of the transmission signal, and passes a signal of a frequency channel different from the frequency channel of the transmission signal.

Disclosed herein are systems and methods for estimating target ranges, angles of arrival, and speed using optimization procedures. Target ranges are estimated by performing an optimization procedure to obtain a denoised signal, performing a correlation of a transmitted waveform and the denoised signal, and using a result of the correlation to determine an estimate of a distance between the sensor and at least one target. Target angles of arrival are estimated by determining ranges at which targets are located, and, for each range, constructing an array signal from samples of received echo signals, and using the array signal, performing another optimization procedure to estimate a respective angle of arrival for each target of the at least one target. Doppler shifts may also be estimated using another optimization procedure. Certain of the optimization procedures use atomic norm techniques.

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.

An apparatus (100) for compensating for weather-independent Doppler expansions in radar signals of a weather radar system (200) is disclosed. The device comprises: a receiving device (110) for receiving a representation (50) of the radar signals, a calculation device (120) and a compensation device (130). The representation includes pixels of a range Doppler matrix. The calculation device (120) is designed to calculate azimuth angles (Azi) for the pixels (75) by means of fine bearing. The compensation device (130) is designed to correct weather-independent Doppler shifts for the pixels (75) based on the calculated azimuth angle (Azi; AziMopu) and thus to compensate for the weather-independent Doppler expansions and to provide them as a compensated representation (150).

Various examples are provided related to penetrating radar based upon precursors. In one example, a method includes transmitting a radio frequency (RF) signal; and receiving a return signal associated with the RF signal, where the return signal is a precursor having no exponential decay. The precursor can be one of a sequence of precursors, which can be used to improve resolution of the system. The RF signal can be a short pulse generated by an RF front end, without automatic level control. The return signal can be processed without filtering.

A communication system, method and computer program product enable transmitting information via the same spectrum as a multiple-input multiple-output (MIMO) radar using the same spectrum. First, a radar system conducts a search mode using a MIMO radar waveform. Second, an uplink communications transmitter employs a new type of signaling that allows the radar to search for targets in the spatial direction of the communication transmitter. Specifically, the MIMO radar can conduct a search task while receiving data from a communication transmitter using the same frequency allocation without blinding the MIMO radar in the direction of the target.

The present invention relates to a method of estimating a velocity magnitude of a moving target in a horizontal plane using radar signals received by a radar detection system, the radar detection system being configured to resolve multiple dominant points of reflection, i.e. to receive a plurality of radar signals from the moving target in a single measurement instance of a single, wherein each of the resolved points of reflection is described by data relating to a range, an azimuth angle and a raw range rate of the points of reflection in said single radar measurement instance. The invention further relates to a radar detection system.

A method of determining an uncertainty estimate of an estimated velocity of an object includes, determining the uncertainty with respect to a first estimated coefficient and a second estimated coefficient of the velocity profile equation of the object. The first estimated coefficient being assigned to a first spatial dimension of the estimated velocity and the second estimated coefficient being assigned to a second spatial dimension of the estimated velocity. The velocity profile equation represents the estimated velocity in dependence of the first estimated coefficient and the second estimated coefficient. The method also includes determining the uncertainty with respect to an angular velocity of the object, a first coordinate of the object in the second spatial dimension, and a second coordinate of the object in the first spatial dimension.