A circuit is described herein. In accordance with one embodiment the circuit includes two or more RF channels, wherein each channel includes an input node, a phase shifter and an output node. Each channel is configured to receive an RF oscillator signal at the input node and to provide an RF output signal at the output node. The circuit further includes an RF combiner circuit that is coupled with the outputs of the RF channels and configured to generate a combined signal representing a combination of the RF output signals, and a monitor circuit that includes a mixer and is configured to receive and down-convert the combined signal using an RF reference signal. Thus a mixer output signal is generated that depends on the phases of the RF output signals.

A radio-frequency receiver includes built-in-self-test (BIST) circuitry which generates a self-test signal. A local oscillator signal is divided. A self-test oscillation signal is generated, based, at least in part, on the frequency-divided local oscillation signal. The self-test signal is generated based on the self-test oscillation signal. The BIST circuitry includes a divider, which divides the self-test oscillation signal. The frequency-divided local oscillation signal and the divided self-test oscillation signal are used to perform one or more of generating the self-test oscillation signal and controlling the generation of the self-test oscillation signal. The radio-frequency receiver may be an automotive radar receiver.

A radar system includes a transmitter including a power amplifier (PA) for amplifying a local oscillator (LO) signal, to generate an amplified signal. The radar system also includes a receiver including an IQ generator for generating an I signal based on the LO signal and for generating a Q signal based on the LO signal and a low noise amplifier (LNA) for amplifying a looped back signal, to generate a receiver signal. The receiver also includes a first mixer for mixing the receiver signal and the I signal, to generate a baseband I signal and a second mixer for mixing the receiver signal and the Q signal, to generate a baseband Q signal. Additionally, the radar system includes a waveguide loopback for guiding the amplified signal from the transmitter to the receiver as the looped back signal.

A method and a device for determining a radar cross section, a method for training an interaction model, a radar target emulator for manipulating a radar signal, and a test facility for a vehicle are described herein. The propagation of a virtual radar signal is simulated on the basis of an interaction model in a simulated environment scenario that contains the simulated radar target. An interaction of the virtual radar signal with the simulated radar target is modelled such that a physical variable, characterizing the virtual radar signal, is divided into a directional component that corresponds to a directed scattering of the virtual radar signal and into a diffuse component that corresponds to an isotropic scattering of the virtual radar signal. A value of the physical variable is determined at a receiver point in the simulated environment scenario, taking into account the directional component and the diffuse component, and the radar cross section of the simulated radar target is derived from the determined value of the physical variable at the receiver point.

A method for self-calibrating a radar system includes forming a calibration loop-back signal path. The calibration loop-back signal path is configured for determining a passband response of each of a radio frequency (RF) signal path, a local oscillator (LO) signal path, and an intermediate frequency (IF) signal path of the radar system. The method also includes transmitting a set of calibration signals into the RF signal path and the LO signal path and measuring output signals from the IF signal path in a receiver of the radar system. The method further includes determining the passband response of each of the RF signal path, the LO signal path and the IF signal path from the measured output signals and compensating for distortions and/or non-linearities in the signal paths using the passband response of each signal path.

An object sensor test system includes a sensor and a test bench. The sensor includes a test interface configured to receive test data and at least one control signal, selectively inject the test data into a selected input of a processing chain based on the at least one control signal, and selectively extract processed test data at a selected output of the processing chain based on the at least one control signal. The test bench is configured to transmit the test data and the at least one control signal to the test interface, receive the processed test data from the sensor, compare the received processed test data with expected data to generate a comparison result, and determine that a segment of the processing chain is operating normally or abnormally based on the comparison result.

A distance measuring device includes a calculating section configured to calculate, based on phase information acquired by a first device and a second device, at least one of which is movable, a distance between the first device and the second device. The first device includes a first reference signal source and a first transceiver configured to transmit two or more first carrier signals and receives two or more second carrier signals using an output of the first reference signal source. The second device includes a second reference signal source configured to operate independently from the first reference signal source and a second transceiver configured to transmit the second carrier signals and receives the first carrier signals using an output of the second reference signal source. The calculating section calculates the distance based on a phase detection result obtained by reception of the first and second carrier signals.

A radar monolithic microwave integrated circuit (MMIC) includes a first transmission channel configured to output a first continuous-wave transmit signal based on a local oscillator signal having a first frequency; a first phase shifter provided on the first transmission channel and configured to apply a first phase setting to the first continuous-wave transmit signal to generate a first transmit signal having the first frequency; a first transmit monitoring signal path configured to couple out a portion of the first transmit signal from the first transmission channel as a first transmit monitoring signal; a frequency multiplier configured to receive a test signal and convert it into a multiplied test signal having a second frequency, where the first and the second frequencies are separated by a frequency offset; and a down-conversion mixer configured to mix the multiplied test signal and the first transmit monitoring signal to generate a first mixer output signal.

A radar device (1) includes a frequency conversion part (12) which converts a frequency of an echo signal obtained by reflecting a detection signal and receiving the reflected detection signal by an antenna (10), and amplifies a signal level thereof. The radar device (1) includes a path switching part (20) which outputs, as a calibration signal, to the frequency conversion part (12), the transmission signal output by the transmission signal generation part (11) at a timing while the transmission signal is output to the antenna (10). A gain adjustment part (23) changes an amplification gain of the frequency conversion part (12) on the basis of a signal level of the calibration signal input to the frequency conversion part (12) and a signal level of the calibration signal having been amplified by the frequency conversion part (12).

A system simulates a moving target for a radar system under test. The system includes a Doppler simulation circuit (DSC), coupled to an input, to apply a frequency shift to RF pulses received on an RF signal to simulate speed. A signal attenuator coupled to the DSC is to simulate signal attenuation due to propagation loss of the RF pulses in atmosphere. A pulse detection circuit is to detect time of receipt of the RF pulses, including a first time of receipt of a falling edge of a first RF pulse. An I/O controller updates a value of the frequency shift for the DSC and of the signal attenuation for the signal attenuator during a time period between the first RF pulse and one of a second RF pulse or a second time at which the second RF pulse should have been received in case of a missing pulse.