A method includes receiving, at a radar timing card, radar timing information and a synchronous clock signal. The method also includes generating, using the radar timing card, a timing trigger to indicate a time of transmission for radar return information. The method further includes receiving, at each of multiple digital-to-analog converter (DAC) channels of one or more DAC cards, the synchronous clock signal and the timing trigger. In addition, the method includes simultaneously transmitting, from each of the DAC channels, a dedicated portion of the radar return information based on the time of transmission indicated by the timing trigger. The synchronous clock signal is used to align the simultaneous transmissions of the DAC channels on the one or more DAC cards.

Methods, apparatus, systems and articles of manufacture to compensate radar system calibration are disclosed. A radio-frequency (RF) subsystem having a transmit channel, a receive channel, and a loopback path comprising at least a portion of the transmit channel and at least a portion of the receive channel, a loopback measurer to measure a first loopback response of the RF subsystem for a first calibration configuration of the RF subsystem, and to measure a second loopback response of the RF subsystem for a second calibration configuration of the RF subsystem, and a compensator to adjust at least one of a transmit programmable shifter or a digital front end based on a difference between the first loopback response and the second loopback response to compensate for a loopback response change when the RF subsystem is changed from the first calibration configuration to the second calibration configuration.

In a radiofrequency (RF) system with multiple transceivers configured to operate together (e.g., in beamforming applications), phase, delay, gain, or other offsets between individual transceivers can be compensated by pairwise measurements of RF signals transmitted by one active transmitter at a time as received by the receiver of the active transceiver and the receiver of another transceiver.

In order to accurately probe a structure of concrete, a series of probe signals with defined carrier frequencies are generated by a probe signal generator and coupled into the structure by an antenna. The returning echo signals are processed by an echo signal receiver. Processing includes phase and amplitude detection in a multiplier, frequency-specific scaling in a scaling unit, replacement of the measured phases and amplitudes in an interpolation unit, and the generation of time-domain data in a Fourier transformation module. The device is robust against RF noise, accurate and low-power.

A method for testing at least one reception path in a radar receiver is provided. The reception path contains a mixer and a downstream signal processing circuit. The method includes injecting a test signal into the radar reception path so that at least a first test tone having a first test tone frequency in a passband of the downstream signal processing circuit and a second test tone having a second test tone frequency outside the passband are present on the radar reception path downstream of the mixer; and determining a characteristic of the radar reception path based on a first characteristic of a baseband signal at the first test tone frequency and a second characteristic of the baseband signal at the second test tone frequency.

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 radio frequency (RF) circuit includes an input terminal configured to receive a reception signal from an antenna; an output terminal configured to output a digital output signal; a receive path including a mixer and an analog-to-digital converter (ADC), wherein the receive path is coupled to and between the input and output terminals, wherein the receive path includes an analog portion and a digital portion, and wherein the ADC generates a digital signal based on an analog signal received from the analog portion; a test signal generator configured to generate an analog test signal injected into the analog portion of the receive path; and a digital processor configured to receive a digital test signal from the digital portion, the digital test signal being derived from the analog test signal, analyze a frequency spectrum of the digital test signal, and determine a quality of the digital test signal.

A circuit includes a radio frequency (RF) channel including an input node and an output node and being configured to receive an RF oscillator signal at the input node and to provide an RF output signal at the output node; a mixer configured to mix an RF reference signal and an RF test signal representative of the RF output signal to generate a mixer output signal; an analog-to-digital converter configured to sample the mixer output signal in order to provide a sequence of sampled values; and a control circuit configured to provide a sequence of phase offsets by phase-shifting at least one of the RF test signal and the RF reference signal using one or more phase shifters, calculate a spectral value from the sequence of sampled values; and calculate estimated phase information indicating a phase of the RF output signal based on the spectral value.

A method for testing at least one reception path in a radar receiver is provided. The reception path contains a mixer and a downstream signal processing circuit. The method involves injecting a test signal into the reception path, so that at least a first test tone having a frequency in a passband of the signal processing circuit and a second test tone having a frequency outside the passband are present on the reception path downstream of the mixer. Further, the method involves tapping off a baseband signal, generated by the signal processing circuit, from the reception path, the baseband signal being based on the test signal.

An object sensor test system includes a sensor and a test bench. The sensor includes a receiver configured to receive a simulated optical signal and a processing chain that includes a plurality of processing components configured to process at least one measurement signal generated in response to the simulated optical signal to generate processed test data. The sensor also includes a test interface configured to receive a control signal, and selectively extract processed test data at a selected output of the processing chain based on the control signal. The test bench is configured to transmit the 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.