A chip-implementation of a millimeter wave MIMO radar comprises transmitters for transmitting short bursts of digitally modulated radar carrier signals and receivers for receiving delayed echoes of those signals. Various signal formats defined by the number of bits per transmit burst, the transmit burst duration, the receive period duration, the bitrate, the number of range bins, and the number of bursts per scan, facilitate the choice of modulating bit patterns such that when correlating for target echoes over an entire scan, the correlation codes for different ranges and different transmitters are mutually orthogonal or nearly so as compared to a random selection of codes. In the event of imperfect orthogonality, the subtraction of strong already-detected target signals allows for better detecting of weaker signals or moving targets that are rendered non-orthogonal by their Doppler shift.

A radar system is provided that includes a radar transceiver integrated circuit (IC) configurable to transmit a first frame of chirps, and another radar transceiver IC configurable to transmit a second frame of chirps at a time delay ΔT, wherein ΔT=T.sub.c/K, K≥2 and T.sub.c is an elapsed time from a start of one chirp in the first frame and the second frame and a start of a next chirp in the first frame and the second frame, wherein the radar system is configured to determine a velocity of an object in a field of view of the radar system based on first digital intermediate frequency signals generated responsive to receiving reflected chirps of the first frame and second digital IF signals generated responsive to receiving reflected chirps of the time delayed second frame, wherein the maximum measurable velocity is increased by a factor of K.

Disclosed is a compact integrated apparatus of an interferometric radar altimeter (IRA) and a radar altimeter (RA) capable of performing individual missions by altitude, which includes: a plurality of antennas; a signal processing control unit selecting an RA mode at a low altitude and selecting an IRA mode at a high altitude based on a mode threshold and selecting an FMCW waveform at the low altitude and selecting an FM pulse waveform at the high altitude based on a waveform threshold; and a transceiving unit transmitting a signal by a first antenna positioned at an outermost portion among the plurality of antennas and receiving a signal by an nth antenna positioned at another outermost portion among the plurality of antennas in the RA mode and transmitting a signal through the first antenna and receiving signals through the plurality of antennas in the IRA mode.

A radar antenna calibration method includes: forming a detection matrix from signals detected by an arrangement of receive antennas in response to chirps transmitted by an arrangement of transmit antennas, the detection matrix having multiple rows corresponding to the chirps, multiple columns corresponding to a signal sample, and multiple planes corresponding the receive antennas; deriving a range matrix by performing a frequency transform on a portion of each row of the detection matrix; extracting a slice of the range matrix, with different rows of the slice being associated with different chirps and with different receive antennas; deriving a velocity matrix from the extracted slice by performing a frequency transform on a portion of each column of the extracted slice; analyzing the velocity matrix to determine a current peak width; and adjusting, based on the current peak width, phase shifts associated with one or more of the receive antennas.

A method for calibrating a radar system includes generating an RF oscillator signal and distributing the RF oscillator signal to a plurality of phase shifters each providing a respective phase-shifted RF oscillator signal; receiving the phase-shifted RF oscillator signals by corresponding radar chips and radiating the phase-shifted RF oscillator signal via a first RF output channel of a first one of the radar chips; receiving a back-scattered signal by at least one RF input channel of each radar chip and generating a plurality of base-band signals by down-converting the received signals into a base band using the phase-shifted RF oscillator signals received by the corresponding radar chips; determining a phase for each base-band signal; and adjusting the phase shifts caused by the phase shifters such that the phases of the base-band signals match a predefined phase-over-antenna-position characteristic.

An estimating method includes: measuring and receiving reception signals including a reflected signal reflected by a moving body, for a first period equivalent to a cycle of movement of the moving body; calculating first complex transfer functions indicating propagation characteristics, from the reception signals measured in the first period; calculating second complex transfer functions having reduced components corresponding to fluctuations, from the first complex transfer functions; extracting moving body information corresponding to a component related to the moving body by extracting moving body information corresponding to a predetermined frequency range of the second complex transfer functions calculated; and estimating a direction in which the moving body is present using the moving body information.

A transceiver circuit included in a computer system may include multiple antennas, a transmitter circuit and a receiver circuit. The transmitter circuit may store an identifier number and generate multiple numbers using the stored identifier number. The transmitter circuit may also generate a transmit signal that include multiple pulses, where a. given pulse may include multiple chirps encoded with the multiple numbers. The receiver circuit may receive a reflected version of the transmit signal and generate an output signal using the reflected version of the transmit signal.

Provided is an information processing apparatus configured to sense an object by using an FMCW radar. The information processing apparatus includes: a data processing unit configured to process a reception signal and generate a power spectrum signal with a predetermined number of bins; an acquisition unit configured to acquire a plurality of peak bins corresponding to the object on the basis of the power spectrum signal; an extraction unit configured to extract an output signal corresponding to the power spectrum signal; and a correction unit configured to correct a phase of the output signal according to bin numbers of the plurality of peak bins. The data processing unit may apply a higher-order window function than a rectangular window to the reception signal. The correction unit may correct the phase of the output signal.

A synthetic aperture radar (SAR) is operable in an interrogation mode and in an imaging mode, the imaging mode entered in response to determining a response to interrogation pulses have been received from a ground terminal and position information specifying a ground location has been received from the ground terminal. A ground terminal is operable to receive interrogation pulses transmitted by a SAR, transmit responses, and transmit position information to cause the SAR to enter a imaging mode. The ground terminal receives first and subsequent pulses from the SAR where subsequent pulses include backscatter and are encoded. The ground terminal generates a range line by range compression. If the SAR is a multi-band SAR the transmitted pulses can be in two or more frequency bands, and subsequent pulses in one frequency band can include encoded returns from pulses transmitted in a different frequency band.

Disclosed is a compact integrated apparatus of an interferometric radar altimeter (IRA) and a radar altimeter (RA) capable of performing individual missions by altitude, which includes: a plurality of antennas; a signal processing control unit selecting an RA mode at a low altitude and selecting an IRA mode at a high altitude based on a mode threshold and selecting an FMCW waveform at the low altitude and selecting an FM pulse waveform at the high altitude based on a waveform threshold; and a transceiving unit transmitting a signal by a first antenna positioned at an outermost portion among the plurality of antennas and receiving a signal by an nth antenna positioned at another outermost portion among the plurality of antennas in the RA mode and transmitting a signal through the first antenna and receiving signals through the plurality of antennas in the IRA mode.