A system for estimating a substance level in a storage unit is disclosed. In one embodiment, the system includes a cable and a control device. The control device sense pulses down the cable and based on the time of reflected pulses determines the level of substance in the storage unit.

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 testing device for testing a distance sensor that operates using electromagnetic waves includes: a receiving element for receiving an electromagnetic free-space wave as a receive signal (S.sub.RX); and a radiating element for radiating an electromagnetic output signal (S.sub.TX). In a test mode, a test signal unit generates a test signal (S.sub.test), and the radiating element is configured to radiate the test signal (S.sub.test) or a test signal (S′.sub.test) derived from the test signal (S.sub.test) as the electromagnetic output signal (S.sub.TX). In the test mode, an analysis unit is configured to analyze the receive signal (S.sub.RX) or the derived receive signal (S′.sub.RX) in terms of its phase angle (Phi) and/or amplitude (A) and store a determined value of phase angle (Phi) and/or amplitude (A) synchronously with the radiation of the test signal (S.sub.test) or of the derived test signal (S′.sub.test) as the electromagnetic output signal (S.sub.TX).

A method of testing vehicular radar includes acquiring binary phase codes of transmitters in a radar DUT; acquiring desired FOVs and desired angular resolutions of the transmitters to determine target angles of emulated targets; calculating far field phases of a PMCW signal for binary phase states of the transmit array at each of the target angles to determine resultant phase symbol streams; calculating excess roundtrip time delay for each emulation delay, between the DUT and the emulated targets, and each setup delay between the DUT and each emulator receiver; time-shifting the resultant phase symbol streams by the excess roundtrip time delays; subtracting the time-shifted resultant phase symbol streams from the resultant phase symbol streams to obtain difference phase symbol streams; modulating a PMCW signal transmitted by the DUT by the difference phase symbol streams; and emulating the echo signals at the target angles in response to the modulated PMCW signal.

A method for calibrating a receiving (Rx) channel of a frequency-modulated continuous-wave (FMCW) radar system includes: setting the Rx channel in calibration mode, where the Rx channel includes a mixer, a phase shifter coupled to a first input of the mixer, a filter coupled to an output of the mixer, and an analog-to-digital converter (ADC) coupled to an output of the filter; setting a value for a phase shifter control word of the phase shifter; sending a chirp signal to the phase shifter; sending a modulated chirp signal to a second input of the mixer, where an output signal at the output of the mixer includes a beat signal; and forming an amplitude curve based on data samples from the ADC, where the amplitude curve illustrates amplitudes of the beat signal at a plurality of frequencies within an operating frequency band of the FMCW radar system.

Example embodiments relate to transmitter-receiver leakage suppression in integrated radar systems. One embodiment includes a front-end for a radar system. The front-end includes a transmit path that includes a power amplifier and a transmit antenna. The transmit path is configured to transmit a transmit signal. The front-end also includes a receive path that includes a receive antenna and a low-noise amplifier. The receive path is configured to receive at least a leakage from the transmit path. The receive path is configured to generate an amplified signal of the leakage. Further, the front-end also includes a reference path. In addition, the front-end includes a compensation unit in the reference path. The compensation unit is configured to generate compensation for a leakage path between the transmit path and the receive path. The compensation unit is configured to apply the generated compensation to the reference signal to generate a compensated reference signal.

A radar target emulator with a superimposition apparatus, having a first input provided to receive a first signal, a second input provided to receive a second signal, a first attenuation device that is connected to the first input in signal-carrying fashion and configured to attenuate the first signal, in particular to a predetermined extent, and to provide a first attenuated signal, a second attenuation device that is connected to the second input in signal-carrying fashion and configured to attenuate the second signal, in particular to a predetermined extent, and to provide a second attenuated signal, an addition device that is configured to add the first attenuated signal and the second attenuated signal and to output a corresponding output signal.

There are provided methods and systems configured to perform calibration of antenna array systems, for example during production, avoiding the use of external setups or external measurements. The method comprising: (i) measuring the delay of a dedicated calibration transmission line for each SUT, for example during production, using internal built-in system capabilities; (ii) comparing the measured delay to a known delay of an identical transmission line of a reference system; (iii) computing, based on this comparison, compensation values with respect to the reference system of delay (or phase), for all transmission lines of the SUT; (iv) calibrating the SUT using the computed compensation values for all transmission lines of the SUT.

Devices and methods for testing altimeters are provided. A radio-frequency (RF) signal may be received from an altimeter and passed through an RF delay module to delay the RF signal. The delayed RF signal may be converted to an optical signal, which may be passed through an optical delay module to delay the optical signal. The system tests the accuracy of the altimeter based on the combined RF signal delay and optical signal delay.

A system and method for extending the path length of an electromagnetic wave signal traveling between apertures is disclosed. One such system may comprise N arrays having M.sub.1 through M.sub.N apertures, respectively, wherein N≥2, M.sub.1≥2, and each of M.sub.2 through M.sub.N≥1, a substantial number of the M.sub.1 apertures in a first array is configured to send the electromagnetic wave signal to a substantial number of the M.sub.2 apertures in a second array through the M.sub.N apertures in a N-th array, the substantial number of the M.sub.2 apertures in the second array through the M.sub.N apertures in the N-th array receiving the electromagnetic wave signal from the substantial number of the M.sub.1 apertures in the first array is configured to redirect the received electromagnetic wave signal back to the substantial number of the M.sub.1 apertures in the first array, and the substantial number of the M.sub.1 apertures in the first array is further configured to send the electromagnetic wave signal to another one of the M.sub.1 apertures in the first array after receiving the redirected electromagnetic wave signal from a M.sub.N-th aperture in the N-th array.