A phase Doppler radar system may comprise a pulse Doppler receiver/transmitter (R/T) subsystem coupled with a processing subsystem. The system may determine target velocity and target detection events by collecting pulses from the pulse Doppler R/T subsystem, determine an undifferentiated phase of each of the pulses, differentiate the pulses, and determine a differentiated phase of each of the pulses. The system may perform a linear fit of the differentiated phases of the pulses to produce a slope and an intercept. The system may determine a set of initial estimates of coefficients of a nonlinear fit equation. The system may perform iterations of a nonlinear least squares fit, beginning with the initial coefficient estimates, to produce a non-linear fit result. The system may determine a goodness-of-fit (GoF) statistic associated with the nonlinear fit result, and declare a detection event when the GoF is superior to a GoF statistic associated Gaussian noise.

A phase Doppler radar system may comprise a pulse Doppler receiver/transmitter (R/T) subsystem coupled with a processing subsystem. The system may determine target velocity and target detection events by collecting pulses from the pulse Doppler R/T subsystem, determine an undifferentiated phase of each of the pulses, differentiate the pulses, and determine a differentiated phase of each of the pulses. The system may perform a linear fit of the differentiated phases of the pulses to produce a slope and an intercept. The system may determine a set of initial estimates of coefficients of a nonlinear fit equation. The system may perform iterations of a nonlinear least squares fit, beginning with the initial coefficient estimates, to produce a non-linear fit result. The system may determine a goodness-of-fit (GoF) statistic associated with the nonlinear fit result, and declare a detection event when the GoF is superior to a GoF statistic associated Gaussian noise.

A method is disclosed for suppressing sidelobes due to artifacts introduced by FFT operations during automotive radar signal processing. Sidelobes of a stronger target from the FFT operations may bury the response from a weaker target when there are multiple targets. The method estimates the sidelobes of an identified target from a measured FFT response and subtracts the estimated sidelobes from the measured FFT response. The identified target may be the strongest target from the measured FFT response. The method estimates the sidelobes to suppress the sidelobes with respect to the peak signal of the identified target. After the estimated sidelobes of the identified target are removed, the updated FFT response may reveal other targets that had been buried. The method may identify additional targets to estimate their sidelobes and may iteratively remove the estimated sidelobes of additional targets from the FFT until a desired sidelobe residual level is achieved.

A method is disclosed for suppressing sidelobes due to artifacts introduced by FFT operations during automotive radar signal processing. Sidelobes of a stronger target from the FFT operations may bury the response from a weaker target when there are multiple targets. The method estimates the sidelobes of an identified target from a measured FFT response and subtracts the estimated sidelobes from the measured FFT response. The identified target may be the strongest target from the measured FFT response. The method estimates the sidelobes to suppress the sidelobes with respect to the peak signal of the identified target. After the estimated sidelobes of the identified target are removed, the updated FFT response may reveal other targets that had been buried. The method may identify additional targets to estimate their sidelobes and may iteratively remove the estimated sidelobes of additional targets from the FFT until a desired sidelobe residual level is achieved.

The present disclosure relates to a method for estimating a wheel base length (D) of at least one trailer (10) of a vehicle combination (100) comprising a towing vehicle (1), the at least one trailer and more than one articulation joint (A1, A2), wherein the towing vehicle comprises at least one wheel identification sensor (2) for identifying wheels (11, 12, 13) of the at least one trailer, the method comprising the following steps: —(S1) performing a plurality of wheel identification measurements on at least one side of the at least one trailer, by means of the at least one sensor during use of the vehicle combination, —(S2) determining a number of identifiable active wheels on the at least one side of the at least one trailer in each one of the plurality of wheel identification measurements, —(S3) determining a total number of active wheels on the at least one side of the at least one trailer, wherein the total number of active wheels is determined based on at least one of the plurality of wheel identification measurements in which a maximum number of identifiable active wheels was determined, —(S4) determining a position of each identifiable active wheel at least from the at least one of the plurality of wheel identification measurements in which the maximum number of active wheels was determined, and —(S5) estimating the wheel base length based on the determined position of each active wheel.

The disclosure discloses a channel combining and time-division processing circuit of a dual-plane pulse Doppler radar seeker. The circuit includes a time-division control circuit configured to receive a time-division control signal, control input of an elevation difference channel signal and an azimuth difference channel signal, combine the elevation difference channel signal and the azimuth difference channel signal and output a combined difference channel signal, and a hybrid bridge circuit configured to receive a sum channel signal, combine channels for the sum channel signal and the combined difference channel signal and output signals on a combined channel. With the circuit of the disclosure, signals received from a sum channel, an azimuth difference channel and an elevation difference channel can be combined into received signals from two channels for processing with one received signal processing channel hardware omitted.

The disclosure discloses a channel combining and time-division processing circuit of a dual-plane pulse Doppler radar seeker. The circuit includes a time-division control circuit configured to receive a time-division control signal, control input of an elevation difference channel signal and an azimuth difference channel signal, combine the elevation difference channel signal and the azimuth difference channel signal and output a combined difference channel signal, and a hybrid bridge circuit configured to receive a sum channel signal, combine channels for the sum channel signal and the combined difference channel signal and output signals on a combined channel. With the circuit of the disclosure, signals received from a sum channel, an azimuth difference channel and an elevation difference channel can be combined into received signals from two channels for processing with one received signal processing channel hardware omitted.

A computer-implemented method is provided for detecting a target amidst clutter by a radar system able to transmit an electromagnetic signal, receive first and second echoes respectively from the target and the clutter, and process the echoes. The method includes determining signal convolution matrix for the target and a target return phase, clutter amplitude by spatial correlation matrix of clutter, clutter correlation matrix, receive noise power; querying whether the clutter moves as a motion condition if satisfied and as a stationary condition otherwise; calculating signal convolution matrix and target return phase from the signal convolution matrix and the target return phase for target motion; querying whether the target has range migration as a migration condition if satisfied and as a non-migration condition otherwise; and forming a target detector for the radar. The motion condition further includes calculating signal convolution matrix from clutter motion, clutter range migration matrix from the clutter motion, and interference correlation matrix. The stationary condition further includes calculating the interference correlation. The migration condition further includes calculating range migration matrix from the target motion.

A radar apparatus includes a plurality of transmit antennas that transmits a plurality of transmission signals using a multiplexing transmission, and a transmission circuit that applies phase rotation amounts corresponding to combinations of Doppler shift amounts and code sequences to the plurality of transmission signals. Each of the plurality of transmission signals is assigned a different combination among the combinations. The combinations include at least one combination of different numbers of multiplexing by the code sequences.

A radio detection and ranging (radar) operating apparatus includes: radar sensors configured to receive signals reflected from an object; and a processor configured to generate Doppler maps for the radar sensors based on the reflected signals and estimate a time difference between the radar sensors based on the generated Doppler maps.