CN117949941A - Method for undistorting radar signal on receiving side, storage medium, electronic control device and radar sensor - Google Patents
Method for undistorting radar signal on receiving side, storage medium, electronic control device and radar sensor Download PDFInfo
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Classifications
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
- G01S7/00—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00
- G01S7/02—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00 of systems according to group G01S13/00
- G01S7/28—Details of pulse systems
- G01S7/285—Receivers
- G01S7/292—Extracting wanted echo-signals
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
- G01S13/00—Systems using the reflection or reradiation of radio waves, e.g. radar systems; Analogous systems using reflection or reradiation of waves whose nature or wavelength is irrelevant or unspecified
- G01S13/02—Systems using reflection of radio waves, e.g. primary radar systems; Analogous systems
- G01S13/50—Systems of measurement based on relative movement of target
- G01S13/58—Velocity or trajectory determination systems; Sense-of-movement determination systems
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
- G01S13/00—Systems using the reflection or reradiation of radio waves, e.g. radar systems; Analogous systems using reflection or reradiation of waves whose nature or wavelength is irrelevant or unspecified
- G01S13/02—Systems using reflection of radio waves, e.g. primary radar systems; Analogous systems
- G01S13/06—Systems determining position data of a target
- G01S13/08—Systems for measuring distance only
- G01S13/10—Systems for measuring distance only using transmission of interrupted, pulse modulated waves
- G01S13/26—Systems for measuring distance only using transmission of interrupted, pulse modulated waves wherein the transmitted pulses use a frequency- or phase-modulated carrier wave
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
- G01S13/00—Systems using the reflection or reradiation of radio waves, e.g. radar systems; Analogous systems using reflection or reradiation of waves whose nature or wavelength is irrelevant or unspecified
- G01S13/02—Systems using reflection of radio waves, e.g. primary radar systems; Analogous systems
- G01S13/06—Systems determining position data of a target
- G01S13/08—Systems for measuring distance only
- G01S13/32—Systems for measuring distance only using transmission of continuous waves, whether amplitude-, frequency-, or phase-modulated, or unmodulated
- G01S13/325—Systems for measuring distance only using transmission of continuous waves, whether amplitude-, frequency-, or phase-modulated, or unmodulated using transmission of coded signals, e.g. P.S.K. signals
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
- G01S7/00—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00
- G01S7/02—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00 of systems according to group G01S13/00
- G01S7/35—Details of non-pulse systems
- G01S7/352—Receivers
- G01S7/354—Extracting wanted echo-signals
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
- G01S7/00—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00
- G01S7/02—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00 of systems according to group G01S13/00
- G01S7/40—Means for monitoring or calibrating
- G01S7/4004—Means for monitoring or calibrating of parts of a radar system
- G01S7/4008—Means for monitoring or calibrating of parts of a radar system of transmitters
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
- G01S7/00—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00
- G01S7/02—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00 of systems according to group G01S13/00
- G01S7/41—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00 of systems according to group G01S13/00 using analysis of echo signal for target characterisation; Target signature; Target cross-section
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- G—PHYSICS
- G06—COMPUTING; CALCULATING OR COUNTING
- G06F—ELECTRIC DIGITAL DATA PROCESSING
- G06F3/00—Input arrangements for transferring data to be processed into a form capable of being handled by the computer; Output arrangements for transferring data from processing unit to output unit, e.g. interface arrangements
- G06F3/01—Input arrangements or combined input and output arrangements for interaction between user and computer
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
- G01S7/00—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00
- G01S7/02—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00 of systems according to group G01S13/00
- G01S7/28—Details of pulse systems
- G01S7/285—Receivers
- G01S7/288—Coherent receivers
- G01S7/2883—Coherent receivers using FFT processing
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
- G01S7/00—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00
- G01S7/02—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00 of systems according to group G01S13/00
- G01S7/35—Details of non-pulse systems
- G01S7/352—Receivers
- G01S7/356—Receivers involving particularities of FFT processing
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- Engineering & Computer Science (AREA)
- Radar, Positioning & Navigation (AREA)
- Remote Sensing (AREA)
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Computer Networks & Wireless Communication (AREA)
- General Engineering & Computer Science (AREA)
- Theoretical Computer Science (AREA)
- Human Computer Interaction (AREA)
- Radar Systems Or Details Thereof (AREA)
Abstract
The invention relates to a method for de-distorting a radar signal of a radar sensor on the receiving side. The following steps are performed: setting (20) a desired signal power of the radar signal, transmitting (21) the radar signal by means of a transmitter (1), receiving (22) the radar signal by means of a receiver (2), preprocessing (23) the received radar signal, determining (24) distorted sample values that are actually transmitted, storing (25) the transmitted distorted sample values, and compensating (35) the radar sensor measurements by means of the transmitted distorted sample values instead of the ideal sample values.
Description
Technical Field
The invention relates to a method for de-distorting (Entzerrung) a radar signal of a radar sensor on the receiving side. The invention also relates to a computer program, a machine-readable storage medium, an electronic control device and a radar sensor.
Background
Nowadays, in addition to modulation types such as frequency modulated continuous wave radar (FMCW) or pulsed radar, digital modulation types such as Orthogonal Frequency Division Multiplexing (OFDM), pseudo-random radar (PN), phase modulated continuous wave radar (PMCW), etc. are also used in radar sensors. These enable significantly greater flexibility in operation. It is important for accurate analysis that radar signals be transmitted and received without error. Due to non-linearities of components such as digital-to-analog converters, IQ modulators, mixers, amplifiers, etcThis is not always the case. This is especially the case when the crest factor of the transmitted signal is large.
To suppress the nonlinearity of the analog components, the signal power is typically reduced on the transmit side, the peak of the time signal thus having a defined reference with respect to the 1dB compression point of the transmit amplifier. The transmit power is reduced by means of an Input-Back-offs (IBO) so that the transmitter operates as linearly as possible. For example, the transmit power is reduced by 10dB with the input back-off. This compensation therefore requires a higher hardware overhead than, for example, FMCW, in which case the full power spectrum of the amplifier can be utilized. In the case of digitally modulated radar sensors, a compromise has thus far been made between high transmission power or high range and good signal quality or measurement quality.
From the communication technology, compensation methods for non-linearities are also known, not only on the transmitting side (predistortion (Vorverzerrung)), but also on the receiving side (de-distortion).
Disclosure of Invention
In the method, the desired signal power of the radar signal is first set and then the radar signal is emitted by the transmitter. The signal power is preferably set by means of a fixed Input Back Off (IBO). The input back-off may preferably be reduced in order to set the desired signal power. In this approach, the non-linearities of the components are no longer compensated for by the input back-off. The input back-off can also be reduced to 0dB or less here, for example, so that the transmitter can be operated with maximum efficiency. In particular, the input back-off is implemented for the transmitter of the radar sensor by means of a digital-to-analog converter by scaling the amplitude of the digital signal values. Alternatively, the input back-off may be implemented in or as a transmitter of the radar sensor by analog and/or digital circuitry. The signal power can be freely selected here and is not as generally limited by the nonlinearity of the component as in conventional approaches. The radar signal is then received by a receiver.
Preferably, a receiver of the radar sensor can be provided as the receiver. In this case, the radar signal may be recorded by the receiver after reflection in the case of using the radar channel, or alternatively directly obtained by crosstalk between the transmitter and the receiver. If a receiver of the radar sensor is used, the de-distortion can be performed entirely in the radar sensor without additional external components. It is thereby achieved that the de-distortion is performed even during radar operation. This may occur in an already set measurement period or be performed in an additional measurement. The de-distortion may also occur upon initial characterization (Charakterisierung) of the radar sensor.
Alternatively, additional measuring receivers can be used in order to record and measure the radar signals of the radar sensor. The additional measuring receiver may be an external measuring receiver and be connected to the radar sensor or to an external analysis processing device. Such an additional measurement receiver is preferably used in the initial characterization of the radar sensor. Alternatively, the additional measuring receiver may also be an integrated circuit on a chip or on a circuit board. The output (Auskopplung) of the transmission signal can be supplied to the measuring receiver, for example, at the output of the transmitter via a directional coupler, a power detector or a mixer. Such an integrated measurement receiver can be used not only for initial characterization but also during operation or between measurements. In particular, the additional measuring receptacle is part of a defined measuring structure, so that the same result is achieved here. In this way, in the case of a plurality of radar sensors, the de-distortion can be performed in rapid succession (IN SCHNELLER Abfolge) by the same measuring receiver.
The received radar signal is mixed down into baseband or onto an intermediate frequency. For this purpose, IQ mixers may be used, but other simple mixers may also be used. The received radar signal is then preprocessed (Calibration preprocessing). The preprocessing consists in particular of time synchronization and optionally of frequency synchronization. Filtering and/or averaging (Mittelung) may also be performed, if desired. In case of using an Orthogonal Frequency Division Multiplexing (OFDM), a Cyclic Prefix (Cyclic Prefix) may be removed.
Subsequently, distorted sampled values that are actually transmitted are determined from the received radar signal. These sampled values are also referred to as samples and are present in the time domain. In this case, the channel estimation is carried out in the time domain by means of distorted sampling valuesTo compensate for the measurement of the radar sensor.
The above steps may be performed in a number of iterations in order to find distorted (verzerrten) sample values as accurately as possible. This is advantageous in particular in the case of arbitrary transmitted data in order to estimate distorted sample values as accurately as possible. Furthermore, the above steps may be repeatedly performed under different conditions, for example, to include temperature dependence, aging effects, environmental influences, and the like. Thereby obtaining distorted sample values for different conditions.
The radar signal may in particular be a radar signal (pre-DEFINED SIGNALS, predefined signal) with predefined transmission data. The radar signal with these transmitted data is then used in the measurement. Since distorted sampling values are used instead of ideal sampling values, no additional computational effort is required in the radar measurement.
In general, any freely selectable transmission data can be used for the radar signal. The distorted sampled values or codes (codes) are then determined, preferably by means of a mathematical model of the sensor. For this purpose, for example, a memory polynomial model, a parallel Hammerstan model, or another nonlinear model or an artificial intelligence-based model can be used as a mathematical model. During the above steps, the model is learned by means of the measured radar signals and its parameters are determined accordingly. This allows the same use of freely selectable radar signals in the measurement. Iterative repetition of steps as described above is particularly advantageous here.
Finally, the distorted sample values that were actually transmitted are stored. n. The larger the transmission power has been selected initially or the smaller the fixed value of the input backoff has been set, the larger the difference between the ideal sample value and the distorted sample value actually transmitted is typically. In addition, power-independent disturbances, such as the frequency response of individual circuits, lines, antennas or other components in the radar sensor, lead to distorted sampling values.
In the measurement operation, the radar measurement of the radar sensor is compensated by means of the transmitted distorted sampling values instead of the ideal sampling values. In this case, the signal power is set in particular by means of a fixed IBO, corresponding to the desired signal power mentioned at the outset.
The compensation in the time domain can be performed, for example, as a correlation or convolution of the received signal with the distorted transmitted signal from the calibration or from the mathematical model or neural model of the transmitter.
In the time domain, the compensation can generally be represented by a channel impulse response.
R (t) is the received signal at the input of the receiver,Is the actual distorted transmit signal at the output of the transmitter, and h (t) is the channel impulse response, each represented in the time domain. Compensated channel estimation with the aid of actual distorted transmitted signal/>Is carried out.
The channel impulse response h (t) may be calculated, for example, by means of channel estimation, which in this example is a division in the frequency domain, calculation:
R (f) is the received signal, and Is an actual distorted transmission signal, and is represented in the frequency domain. /(I)Representing a fourier transform in the time domain.
Instead of sampling values, coding may be used for de-distortion. The code is modulated data obtained by I/Q modulation in transmission, such as Phase-shift keying data (Phase-SHIFT KEYING, PSK) or quadrature amplitude modulation data (QAM). The code is obtained by decoding the sample values by fourier transformation and is present in the frequency domain. In the method, a distorted code representing distorted modulated data in transmission is calculated from the radar signal. The distorted code is stored and used as calibration data. In this case, the compensation of the measurement of the radar sensor takes place in the frequency domain by means of distorted coding by means of channel estimation.
If an orthogonal frequency division multiplexing method is used, it is preferable to find and store the codes of the transmitted distortions for the sum of the individual subcarriers of the orthogonal frequency division multiplexing method for each symbol of the orthogonal frequency division multiplexing method.
Preferably, in the measurement compensation in the frequency domain, instead of ideal coding, the channel matrix is calculated using the transmitted distorted coding. The following examples are suitable for use of the OFDM method.
N denotes the sample points (after the first fast fourier transform), i.e. the frequency points or subcarriers, transformed into the frequency domain within each symbol. μ represents the symbol index within the symbol being issued. In this case, one symbol is sufficient, but a plurality of, for example eight symbols, can also be implemented. H (n, μ) describes the estimated channel matrix in the frequency domain for frequency bins or subcarriers n and symbols μ. C Rx (n, μ) is the code for the received radar signal, while C Tx (n, μ) is the ideal code for the transmitted radar signal. The latter by the actual transmitted distorted codingInstead, to obtain the actual channel matrixIn the case of OFDM, the actual distorted transmitted signal/>Coding/>, corresponding to the distortion actually transmittedAnd the received signal R (f) corresponds to the received code C Rx.
Depending on the modulation type and the channel estimation method, the distortion is transformed into a corresponding domain or representation, thereby obtaining data suitable for de-distortion. Alternative channel estimation methods, such as matched filters, are applied not only to the coding but also to the sample values.
The method may alternatively be applied to a multiple-input multiple-output radar sensor (MIMO). For this purpose, the above-described steps are carried out for each transmitter in order to obtain, for each transmitter, the actual transmitted distorted sample value or code.
In the case of interference, depending on the backscatter cross section or the transmit power, unknown objects in the radar channel may lead to erroneous determination of distorted sample values. In particular, methods known per se can be applied in the context of the preprocessing of radar signals, by means of which only suitable targets, for example only stationary targets, are used.
As a result, the interference effects of the transmitter are compensated for in the receiver or in the reception path in the signal processing. The method provides the following advantages: the amplifier power in the transmitter need not be limited. The nonlinearity of the component is directly contained in the distorted sampled value or code at the selected transmission power and can thus be compensated for. Thus achieving a better utilization of the available amplifier power in the transmitter. Ghost targets (Geisterziele) that may occur due to interference effects are also suppressed. Furthermore, an improvement in signal-to-noise ratio at the same transmit power is achieved in radar measurements. Alternatively, the transmission power increase is achieved with the amount of distortion (maβ) remaining the same, which is also used for signal-to-noise improvement. The range of the radar sensor is thereby increased without this resulting in a deterioration of the measurement quality and/or of the measurement dynamics.
The present method provides advantages over signal-only analysis: the analysis is carried out in the digital domain, in which the sample values or codes are already present.
A computer program is provided for carrying out each step of the method, in particular when the computer program is executed on a computing device or a control device. The computer program enables the implementation of the method in a conventional electronic control device without having to make structural changes on the control device. To this end, the computer program is stored on a machine-readable storage medium.
By running the computer program on a conventional electronic control device, the following electronic control device is obtained: the control device is arranged for performing a de-distortion of the receiving side of the radar signal.
Furthermore, a radar sensor is provided, which has a transmitter and a receiver. Furthermore, the radar sensor has a preprocessing unit and a compensation unit. In particular, the radar sensor may have the above-described electronic control device. In this case, the preprocessing unit and the compensation unit may be part of the electronic control device. The radar sensor is arranged to perform each step of the method in order to de-distort the radar signal used for the measurement.
Drawings
Embodiments of the invention are illustrated in the drawings and described in more detail in the following description.
Fig. 1 shows a block diagram of a radar sensor.
Fig. 2 shows a flow chart of an embodiment of the method according to the invention in one calibration cycle.
Fig. 3 shows a flow chart of an embodiment of the method according to the invention in one measurement cycle.
Detailed Description
Fig. 1 shows a radar sensor according to the invention, which has a transmitter 1 and a receiver 2. A Transmitter (Transmitter) 3 generates a radar signal, which is output by a Transmitter 1. These radar signals undergo a digital-to-analog converter 4 (digital-to-analog converter DAC), an IQ mixer 5 and a power amplifier 6 before they are output from a transmit antenna 7 into a radar channel H. The receiver 2 has a receiving antenna 8 by means of which radar signals are recorded from a radar channel H. In addition, crosstalk may occur between the transmitter 1 and the receiver 2. The received radar signal is subjected to a low noise amplifier 9, another IQ mixer 10 and an analog-to-digital converter (ADC). The IQ mixers 5 and 10 are connected to each other through a local oscillator 11, and modulation or demodulation of radar signals is performed. The components digital-to-analog converter 4, IQ mixers 5, 10, power amplifier 6, low noise amplifier 9, further IQ mixer 10 and analog-to-digital converter 12 typically suffer from non-linearities. The received radar signal is supplied to a pre-processing unit 13, the function of which is described in detail in connection with fig. 2. The preprocessed radar signal is then supplied to the compensation unit 14, the function of which is likewise described in detail in connection with fig. 2. In the compensation unit 14, the radar signal is compensated in the measurement cycle by means of the distorted code that is actually transmitted. Finally, the compensated radar signal is analyzed and processed in a signal analysis processing unit 15.
Fig. 2 shows a flow chart of the method according to the invention during a calibration period. First, a desired signal power for a predefined radar signal is set in the transmitter 3 by inputting the back-off 20. The predefined radar signal is then sent 21 by the transmitter 1 into the radar channel H. In this embodiment, the receiver 2 receives 22 the emitted radar signal from the radar channel H, and the received radar signal is mixed down into baseband or onto an intermediate frequency by the IQ mixer 10 and sampled. In the preprocessing unit 13, a preprocessing 23 is performed, in which time synchronization, amplitude scaling and, if necessary, frequency synchronization are performed. Further, filtering and/or averaging may be performed. In the case of using the orthogonal frequency division multiplexing method, the cyclic prefix is additionally removed. Subsequently, by means of a fourier transformation, a distorted code that is actually transmitted is calculated 24 in the frequency domain from the received radar signal(N, μ) and stores 25 distorted codes/>
Fig. 3 shows a flow chart of the method according to the invention during a measurement cycle. In the transmitter 3, the signal power of the radar signal for measurement is set 30 to the same or similar level as the signal power in the calibration phase (see 20). The transmitter 3 then loads 31 a predefined radar signal corresponding to the predefined radar signal in the calibration phase and outputs the predefined radar signal. To perform the measurement, the transmitter 1 emits 32 the radar signal into the radar channel H, and the receiver 2 receives 33 the radar signal from the radar channel H, and the received radar signal is mixed down into baseband or onto an intermediate frequency by the IQ mixer 10 and sampled. Subsequently, as described above, preprocessing 34 of the received radar signal is performed in the preprocessing unit 13. According to the invention, coding by means of distortion that is actually transmittedThe measurement is compensated 35 in the compensation unit 14. In the measured compensation 35, instead of an ideal coding, a coding for the transmitter 1 for the transmitted distortion/>, is usedIn the case of code C Rx (n, μ) of the received radar signal, the actual channel matrix/>, for radar channel H is calculated according to the following formula
The compensated radar signal 15 is then analyzed 36 in the signal analysis processing unit 15 by means of conventional methods.
In a further embodiment not shown here, the sampled values of the radar signal can be used directly. In the case of channel estimation in the time domain, the sample values of the signal actually transmitted may be stored 25 directly after the preprocessing 23.
Claims (14)
1. A method for de-distorting a radar signal of a radar sensor at a receiving side, characterized by the steps of:
-setting (20) a desired signal power of the radar signal;
-sending out (21) the radar signal by a transmitter (1) and receiving (22) the radar signal by a receiver (2);
-pre-processing (23) the received radar signal;
-obtaining (24) distorted sample values that are actually transmitted;
-storing (25) the transmitted distorted sample values;
-compensating (35) the radar sensor measurements by channel estimation by means of transmitted distorted sample values instead of ideal sample values.
2. The method of claim 1, wherein the distorted code is derived from actual derived distorted sample valuesAnd encoded with the distortion/>Stores (25) the transmitted sample values and in the frequency domain by means of the distorted coding/>Compensation (35) of the radar sensor measurements is performed by channel estimation.
3. Method according to claim 2, characterized in that an orthogonal frequency division multiplexing method is used and that the coding of the transmitted distortion for each subcarrier and for each symbol of the orthogonal frequency division multiplexing method is solved (24) and stored (25)
4. A method according to claim 2 or 3, characterized in that in compensating (35) the measurement, instead of an ideal code, a distorted code transmitted is used in the codeIs used to calculate the channel matrix.
5. A method according to any of the preceding claims, characterized by reducing an input back-off in order to set the desired signal power.
6. Method according to any of the preceding claims, characterized in that the step of calibrating the emission (21) of the radar signal, the step of receiving (22) the transmitted radar signal, the step of preprocessing (23) the received radar signal and the step of finding (24) the actually transmitted distorted sample value are performed a number of times iteratively before storing (25) the transmitted distorted sample value or code.
7. Method according to any of claims 1 to 6, characterized in that the radar signals have transmission data that are predefined in advance, and that radar signals with these transmission data are used in the measurement.
8. Method according to any of claims 1 to 6, characterized in that the radar signal has freely selectable transmission data, that the distorted sampled values are determined by means of a mathematical model of the sensor, and that the freely selectable radar signal is used in the measurement.
9. Method according to any of claims 1 to 8, characterized in that the radar signal is received by a receiver (2) of the radar sensor.
10. The method according to any one of claims 1 to 8, characterized in that the radar signal is measured by an additional measurement receiver.
11. A computer program arranged to perform each step of the method according to any one of claims 1 to 10.
12. A machine readable storage medium on which is stored a computer program according to claim 11.
13. An electronic control device arranged for de-distorting radar signals by means of a method according to any one of claims 1 to 10.
14. Radar sensor having a transmitter (1) and a receiver (2) and a preprocessing unit (13) and a compensation unit (14), wherein the radar sensor is provided for de-distorting radar signals by means of the method according to any one of claims 1 to 9.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DE102022211539.2A DE102022211539A1 (en) | 2022-10-31 | 2022-10-31 | Method for receiver-side equalization of radar signals |
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