Abstract: A method and an apparatus for recognizing an absorptive radome coating on an apparatus for emitting electromagnetic radiation and receiving partial radiation reflected at objects is disclosed. The radome covers at least one antenna of the apparatus. A mixer mixes a frequency-modulated transmission signal with the signal received by the at least one antenna, the mixed product of the mixer is subjected to analog-to-digital conversion, the digitized signal is transformed into a two-dimensional spectrum, and the two-dimensional spectrum is mapped with a transfer function. The two-dimensional spectrum that was mapped with the transfer function is correlated with correlation matrices in order to carry out pattern recognition.

Abstract: A method and an apparatus for recognizing an absorptive radome coating on an apparatus for emitting electromagnetic radiation and receiving partial radiation reflected at objects is disclosed. The radome covers at least one antenna of the apparatus. A mixer mixes a frequency-modulated transmission signal with the signal received by the at least one antenna, the mixed product of the mixer is subjected to analog-to-digital conversion, the digitized signal is transformed into a two-dimensional spectrum, and the two-dimensional spectrum is mapped with a transfer function. The two-dimensional spectrum that was mapped with the transfer function is correlated with correlation matrices in order to carry out pattern recognition.

Abstract: A method for determining a degree of blindness of a radar sensor in a motor vehicle on the basis of a measurement of the receive power level of a radar echo, including the following steps that are carried out when at least one object is located by the radar sensor: determining an expected value for the radar scatter cross-section of the object on the basis of known properties of objects to be located; estimating the radar scatter cross-section of the located object on the basis of the measured receive power level; and calculating an indicator for the degree of blindness of the radar sensor as a monotonically increasing function of the difference between the estimated radar scatter cross-section and the expected value.

Abstract: A method for determining a degree of blindness of a radar sensor in a motor vehicle on the basis of a measurement of the receive power level of a radar echo, including the following steps that are carried out when at least one object is located by the radar sensor: determining an expected value for the radar scatter cross-section of the object on the basis of known properties of objects to be located; estimating the radar scatter cross-section of the located object on the basis of the measured receive power level; and calculating an indicator for the degree of blindness of the radar sensor as a monotonically increasing function of the difference between the estimated radar scatter cross-section and the expected value.

Abstract: A method for determining an indicator for a blindness of a radar sensor, includes: controlling the radar sensor to transmit a transmission signal in the form of at least two successive frequency ramps having the same ramp slope and in the same frequency range, and to receive detection signals associated with the frequency ramps; examining, for multiple frequencies, whether a ratio between the received powers in the frequency spectra of the received signals, at a respective frequency, corresponds to a ratio between the transmission powers of the associated frequency ramps; and determining an indicator for a blindness of the radar sensor based on the result of the examinations.

Abstract: A method for determining an indicator for a blindness of a radar sensor, includes: controlling the radar sensor to transmit a transmission signal in the form of at least two successive frequency ramps having the same ramp slope and in the same frequency range, and to receive detection signals associated with the frequency ramps; examining, for multiple frequencies, whether a ratio between the received powers in the frequency spectra of the received signals, at a respective frequency, corresponds to a ratio between the transmission powers of the associated frequency ramps; and determining an indicator for a blindness of the radar sensor based on the result of the examinations.

Abstract: In a method for checking the functionality of a mixer, the mixer is supplied with a high-frequency signal and a high-frequency comparison signal in order to generate a baseband signal. The amplitude of the high-frequency signal is modified as a function of time. A direct-current voltage component of the baseband signal which is output by the mixer is analyzed to determine the functionality of the mixer.