A multiple-input multiple-output (MIMO) radar system, including: a plurality of transmit channels configured to sequentially transmit signals with transmit-channel-designated Doppler division multiplexing (DDM) modulations; and processing circuitry configured to: determine, for each of the transmit channels, an impulse response of phase modulation errors due to DDM coupling of the respective transmit channel from each of the other transmit channels; and generate, based on the impulse response, a reconstruction matrix of modulation DDM coupling factors.

A method for the use in a radar system is described herein. In accordance with one embodiment, the method includes providing a local oscillator signal to an RF output channel of a radar system. The RF output channel is configured to generate, in an enabled state, an RF output signal based on the local oscillator signal. The method further includes determining a first measurement signal based on the local oscillator signal and a first representation of the RF output signal, while the RF output channel is disabled, and thus the first measurement signal represents crosstalk. Further, the method includes determining a second measurement signal based on the local oscillator signal and a second representation of the RF output signal while the RF output channel is enabled. A phase value associated with the RF output channel is determined based on the first measurement signal and the second measurement signal.

A radar system, apparatus, architecture, and method are provided for generating a transmit reference or chirp signal to produce a plurality of transmit signals having different frequency offsets from the transmit reference signal for encoding and transmission as N radio frequency encoded transmit signals which are reflected from a target and received at a receive antenna as a target return signal that is down-converted to an intermediate frequency signal and converted by a high-speed analog-to-digital converter to a digital signal that is processed by a radar control processing unit which performs fast time processing steps to generate a range spectrum comprising N segments which correspond, respectively, to the N radio frequency encoded transmit signals transmitted over the N transmit antennas.

Aspects of the present disclosure are directed to radar transmissions and related componentry. As may be implemented in accordance with various embodiments, radar signals are generated and transmitted using both scanning and fixed beam analog signal codes concurrently/as combined for each radar signal. Reflections of the radar signals from a target are processed for ascertaining positional characteristics of the target.

In accordance with a first aspect of the present disclosure, a system is provided for facilitating detecting an external object, the system comprising: at least one first communication unit configured to transmit and receive one or more first signals; at least one second communication unit configured to transmit and receive one or more second signals; a controller configured to control the first communication unit and the second communication unit, wherein the controller is configured to cause the first communication unit and the second communication unit to operate concurrently and to use the first signals received by the first communication unit and the second signals received by the second communication unit while said first communication unit and second communication unit are operating concurrently for detecting the external object. In accordance with other aspects of the present disclosure, a corresponding method for facilitating detecting an external object is conceived, as well as a computer program for carrying out said method.

A method for determining at least one object information item of at least one target object (18) which is sensed with a radar system (12), in particular of a vehicle (10), a radar system (12) and a driver assistance system (20) are described. In the method, transmission signals (32a, 32b) are transmitted into a monitoring range (14) of the radar system (12) with at least one transmitter (26a, 26b). Echoes, which are reflected at the at least one target object (18), of the transmission signals (32a, 32b) are received as received signals (34a, 34b) with at least one receiver (30), and if necessary are converted into a form which can be used by an electronic control and/or evaluation device (28). The received signals (34a, 34b) are subjected to at least one multi-dimensional discrete Fourier transformation. At least one target signal is determined from the result of the at least one Fourier transformation. At least one object information item is determined from the at least one target signal. At the transmitter end, at least one first transmission signal (32a) and at least one second transmission signal (32b) are generated from a frequency-modulated continuous wave signal. The at least one second transmission signal (32b) is encoded by means of phase modulation with respect to the at least one first transmission signal (32a), with the result that an at least temporary signal orthogonality between the at least one first transmission signal (32a) and the at least one second transmission signal (32b) is obtained. The at least one first transmission signal (32a) is emitted with at least one first transmitter (26a), and the at least one second transmission signal (32b) is emitted with at least one second transmitter (26b), simultaneously into the monitoring range (14) of the radar system (12). The at least one second transmission signal (32b) is emitted with regular transmission pauses of a predefined length.

A radar apparatus includes a radar transmission circuit that transmits a radar signal from a transmission array antenna, and a radar reception circuit that receives, from a reception array antenna, a reflected wave signal that is the radar signal reflected at a target. One of the transmission array antenna and the reception array antenna includes a first antenna element group having m antenna elements arranged at a first interval D.sub.t along a first axis direction, wherein m is an integer of 2 or larger. The other one of the transmission array antenna and the reception array antenna includes a second antenna element group having n antenna elements arranged at a second interval D.sub.r along the first axis direction, wherein n is an integer of 4 or larger. The second interval D.sub.r includes several different intervals.

A multi-input multi-output (MIMO) radar system and method of performing low-latency decoding in a MIMO radar system. The method includes transmitting a different linear frequency-modulated continuous wave (LFM-CW) transmit signal from each of N transmit elements of the MIMO radar system, each transmit signal associated with teach of the N transmit elements including a respective code, and receiving reflections associated with each of the transmit signals from each of the N transmit elements at each receive element of the MIMO radar system. Processing each symbol corresponding with each received reflection on a symbol-by-symbol basis is done to obtain a respective decoded signal prior to receiving all the received reflections associated with all the N transmit elements, wherein the processing includes using a Hadamard matrix with N columns in which each column is associated with the respective code transmitted by each of the N transmit elements.

The present disclosure is directed to the transmission and reception of sets of very high frequency electromagnetic (EM) signals in ways that allow a sensing apparatus to discriminate between different sets of transmitted EM signals. Here a sensing apparatus may sequentially transmit different sets of EM signals. Each of these different sets of signals may include an encoded identifier that uniquely identifies each respective signal set of the different sets of signals. Each of these signal sets may include several pulses of a particular frequency with a same relative phase relationship followed by pulses that have a different phase relationship. These changes in phase may be used to encode the unique identifiers into the different sets of transmitted EM energy and these identifiers may be used by a sensing apparatus to associate specific received sets of EM energy with specific sets of transmitted EM energy.

Time-division quadrature sampling may be used in a pulse-modulated continuous wave (PMCW) radar receiver circuit, e.g., as may be employed in various types of radar sensors used in automotive and other applications, to enable a quadrature sampling circuit to sequence between digitally sampling different complex components of a received radar signal at different times.