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.

The present disclosure relates to apparatuses and methods for a radar device. For example, an antenna device has a first set of antennas to establish first propagation channels and a second set of antennas to establish second propagation channels. A signal processing device determines a first differential phase shift among first radar signals propagating via the first propagation channels and a second differential phase shift among second radar signals propagating via the second propagation channels. Antennas of the first set are located at positions that generate the first differential phase shift for a first multitude of target angles, and antennas of the second set are located at positions that generate the second differential phase shift for a second multitude of target angles. The processing device determines an angular position of a target object as a unique target angle that is part of the first and second multitude of target angles.

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 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.

A maritime radar system is provided, comprising a transmitter, a receiver, and one or more processors arranged to provide range and azimuth discrimination of a detection area by performing a delay/Doppler analysis of the echo of a single beam transmitted by the transmitter and received by the receiver.

Aspects of the present disclosure are directed to radar and radar processing. As may be implemented in accordance with one or more embodiments involving multi-input multi-output (MIMO) co-prime radar signals transmitted by a plurality of transmitters and reflected from at least one target, the reflected radar signals are processed by resolving ambiguities associated with a range-Doppler detection based on unique pulse repetition frequencies (PRF)s associated with respective chirp groups of the reflected radar signals. Phase compensation is applied to compensate for motion-induced phased biases and, thereafter, Doppler estimates are reconstructed to provide a dealiased version of the reflected radar signals.

A radar apparatus includes a plurality of transmission antennae and a radar transmitter that transmits transmission signals by using the plurality of transmission antennae. In a virtual reception array including a plurality of virtual antennae formed of a plurality of reception antennae and the plurality of transmission antennae, disposition positions of at least two of the virtual antennae are the same as each other, and, transmission intervals of the transmission signals that are sequentially transmitted from transmission antennae corresponding to the at least two virtual antennae among the plurality of transmission antennae are an equal interval.

There is described a radar system (100) and a corresponding method, the radar system (100) comprising i) a control unit (110), configured for generating a code (C) comprising a sequence of code symbols (211), wherein generating the code (C) comprises randomly selecting a plurality of code symbols (211) from a code symbol pool (310) comprising a plurality of code symbols (211), ii) a transmitter (120), configured for generating a signal (S) from the code (C), and further configured for transmitting the signal (S), iii) a receiver (130), configured for receiving an echo (E) of the signal (S), and iii) a correlator (140), configured for correlating each code symbol of the code (C′) of the received echo (E) of the signal (S) to a corresponding symbol template (R) associated with the correlator (140); wherein the radar system (100) is further configured for synchronizing the symbol template (R) to the code (C) of the signal (S). There is further described a method of using a sequence of randomly selected code symbols (211) in a radar application, in particular an UWB-based radar application, to prevent replay attacks.

It is described a radar system (100), comprising: i) a transmitter (120) configured to: provide a code (C), identify a plurality of regions (R) within the code (C), apply a transmitter-specific cyclic shift scheme to the plurality of regions (R), generate a signal (S) from the code (C) and transmit the signal; and ii) a receiver (130), configured to: receive an echo (E) of the signal (S), and identify the transmitter (120) based on the transmitter-specific cyclic shift scheme.

Further, a radar arrangement and a method of performing a radar operation are described.

Disclosed is a method and apparatus for generating a radar signal, in which performance of radar detection is ensured while increasing a spectrum efficiency in a radar network. The method comprises generating a set of frequency-modulation waveforms, generating an orthogonal code set, generating a set of coded frequency-modulation waveforms through element operation between the set of frequency-modulation waveforms and the orthogonal code set, calculating an objective function for the set of frequency-modulation waveforms with regard to a different set of coded frequency-modulation waveforms and previous sets of coded frequency-modulation waveforms, and selecting a current polyphase code set as an optimized polyphase code set when a result of current calculation is better or smaller than a result of previous iteration, and performing phase perturbation by replacing an element randomly selected in the current polyphase code set selected as the optimized polyphase code set with another admissible-phase element.