Test device for testing distance sensor operating by means of electromagnetic waves

Abstract

To provide a test device for testing a distance sensor capable of simulating a reflection signal, and a method.SOLUTION: During simulation operation, a reception signal is converted into a sampling signal, the sampling signal is time-delayed by using pre-settable time-delay so as to generate a time-delay sampling signal (11); the time-delay sampling signal is converted into a simulate reflection signal, and the simulate reflection signal is radiated as an output signal. A signal processing unit (5) superimposes a Doppler signature that can be preset as a motion profile particular to a reflection object to be simulated on the sampling signal or time delay sampling signal and modulates it (12); and the time-delay sampling signal to which the Doppler signature is additionally applied is converted into a simulate reflection signal, and a simulate reflection signal having the Doppler signature can be easily generated.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to a test apparatus for testing an electromagnetic wave-operated distance sensor. The test apparatus comprises a receiving member that receives free-space electromagnetic waves as a received signal, and a radiating member that radiates an electromagnetic output signal. During simulation operation, the received signal or a received signal derived from this received signal is converted into a sampled signal by an analog-to-digital converter. This sampled signal is time-delayed by a signal processing unit using a preset time delay so that a time-delayed sampled signal is generated. The time-delayed sampled signal is converted into a simulated reflected signal by a digital-to-analog converter, and the simulated reflected signal or a simulated reflected signal derived from this simulated reflected signal is radiated as an output signal via the radiating member. Furthermore, the present invention relates to a method performed by the signal processing unit of the above-described test apparatus for testing an electromagnetic wave-operated distance sensor, and to a computer program that, when executed by the signal processing unit of the aforementioned test apparatus for testing an electromagnetic wave-operated distance sensor, includes instructions that cause the signal processing unit to perform the above-described method. [Background technology]

[0002] The above-described type of test apparatus for testing distance sensors and methods for operating this type of test apparatus are publicly known from various technical fields and application areas, for example, from the fields of control equipment development and control equipment testing, and especially in the automotive field. For this, see, for example, International Publication No. 2020 / 165191. Another application area is end-of-line test stands, which are devices used for product testing, in this case distance sensor testing, at the end of a manufacturing line. In this case, the subject is testing distance sensors that operate using electromagnetic waves. In the automotive field, radar sensors are used in the vast majority of cases. However, basically, distance sensors that operate in other frequency ranges of electromagnetic waves, for example in the visible light range, can also be tested, or distance sensors that operate using electromagnetic radiation sources that emit electromagnetic waves with a long coherence length, such as in laser applications (e.g., Lidar), can also be tested.

[0003] The test apparatus described at the beginning can be made to appear to the distance sensor under test as if a reflective object were present at virtually any distance. The type of distance sensor considered herein basically operates as follows: electromagnetic waves emitted from the distance sensor are reflected by reflective objects within the distance sensor's radiation region, the distance sensor receives the reflected electromagnetic waves, and determines the distance to the object from the propagation time of the electromagnetic waves. Although the signal propagation time can be determined directly (time-of-flight measurement), it is often done indirectly through clever signal evaluation. In the former case, a very short sensor signal, i.e., a pulse, is often used, whereas in the latter case, a time-recognizably extended transmitted signal is usually used, and the desired distance information is obtained from the frequency of a mixed signal consisting of the transmitted signal and the received reflected signal. An example of a time-reextended transmitted signal would be a frequency-modulated continuous wave signal.

[0004] The test device is positioned within the radiation range of the distance sensor to test the distance sensor. The test device receives the free-space wave emitted from the distance sensor, delays this received signal according to a preset time delay using its own signal processing unit, and then emits the time-delayed signal again in the direction of the distance sensor under test through its own radiating element. This creates the impression in the distance sensor that a reflective object exists at a distance corresponding to the set time delay.

[0005] If a reflective object that reflects a transmitted signal from a distance sensor has a radial motion component relative to the distance sensor, then this reflected signal will be frequency-shifted relative to the frequency of the transmitted signal from the distance sensor, based on the Doppler effect. Many distance sensors also evaluate the reflected signal in terms of frequency shift in order to obtain velocity information related to the radial motion component. For this purpose, it is not necessary to directly determine the frequency of the reflected signal; rather, as in the case of determining time delay, a clever signal evaluation can be performed, for example, the phase shift between a mixed signal consisting of multiple transmitted and received signals can be evaluated, but a rigorous evaluation is not important here. Rather, what is important is that the test apparatus and the method for operating this test apparatus discussed here must also be able to perform a corresponding frequency shift of the simulated reflected signal relative to the frequency of the received signal in order to depict a predetermined radial motion component in the simulated reflected signal.

[0006] Some reflective objects have motion profiles that include not just one radial motion component, but multiple radial motion components resulting from the movement of objects relative to each other. This is true, for example, for pedestrians (movement of arms, legs, and torso), bicycles (frame, spokes), or helicopters (fuselage, rotor blades). Regardless of whether the reflective object has one or multiple motion components, the reflected signal will still leave a distinctive Doppler signature. [Overview of the Initiative] [Problems that the invention aims to solve]

[0007] Future distance sensors will, in some cases, perform evaluations of more complex Doppler signatures when evaluating reflected signals. Therefore, the object of the present invention is to provide a test apparatus for testing distance sensors and a corresponding method for operating such a test apparatus, which can simulate appropriate reflected signals. [Means for solving the problem]

[0008] The problems derived above are solved in the test apparatus and the method for operating the electromagnetically operated distance sensor described at the beginning by having the signal processing unit modulate the sampled signal or time-delayed sampled signal by superimposing a Doppler signature, which can be preset as the specific motion profile of the reflective object being simulated. Furthermore, the time-delayed sampled signal with the additionally Doppler signature is then converted into a simulated reflection signal by a digital-to-analog converter.

[0009] A key aspect of the test apparatus and method for operating the test apparatus according to the present invention is that modulating a sampled signal or a time-delayed sampled signal by superimposing a preset Doppler signature falls entirely within the realm of digital signal processing, which is significantly simpler and more flexible to implement than analog solutions. To this extent, the solution according to the present invention also assumes a test apparatus equipped with a signal processing unit implemented by digital technology, and does not assume a test apparatus involving signal processing implemented by analog circuit technology. Signal processing units implemented by analog circuit technology are used quite extensively, and they operate, for example, by cascaded signal delay lines. The signal processing units used herein are implemented, for example, based on a digital signal processor, or by logic components configured in the form of a field-programmable gate array (FPGA).

[0010] A pre-configurable Doppler signature describes which specific frequency components the simulated reflected signal should have. Therefore, in the case of a pedestrian approaching a distance sensor as a reflective object with a radial motion component, the Doppler signature describes the higher-frequency shifted component of the radar signal reflected from the pedestrian's torso with the highest energy component, and the numerous reflected signal components shifted to higher and lower frequencies relative to the torso, caused by the pendulum motion of the limbs, with relatively smaller energy components. Naturally, reflective objects containing only a single radial motion component, such as a car, can also be simulated. In this case, the Doppler signature is much simpler. The Doppler signature must be selected so that, when superimposed on a sampled signal or a time-delayed sampled signal, it results in a desirable specific motion profile in the simulated reflected signal.

[0011] In this specification, a received signal and a received signal derived from this received signal are always conceptually distinguished. The received signal itself originates from a free-space wave captured by the receiving component of the test apparatus. If further signal processing is performed before sampling by the analog-to-digital converter, then strictly speaking, it is no longer the received signal itself, but a received signal derived from it. This is true, for example, when the received signal is down-converted to a lower intermediate frequency, thereby reducing the technical requirements for the signal transmission path, and further reducing the requirements for high-speed signal processing, especially for analog-to-digital conversion. This naturally also applies to simulated reflected signals and simulated reflected signals derived from these simulated reflected signals (e.g., up-converted to a desired transmission frequency) after digital-to-analog conversion.

[0012] According to one variation of the test apparatus and the method for operating it, the following configuration is achieved: the signal processing unit first modulates the sampled signal by superimposing a Doppler signature, and then delays the Doppler-signatured sampled signal using a preset time delay so that a time-delayed sampled signal is generated. Accordingly, according to another variation of the test apparatus and the method for operating it, the following configuration is achieved: the signal processing unit first delays the sampled signal using a preset time delay, and then modulates it by superimposing a Doppler signature, thus generating a time-delayed sampled signal with an additional Doppler signature. In other words, the order in which the time delay and superimposed modulation of the Doppler signature are performed can be realized in different ways. In terms of time delay, the unavoidable latency caused by other signal processing in the signal processing unit or the test apparatus must always be taken into consideration, but this is no different from known test apparatuses and methods for operating them.

[0013] One preferred embodiment of the test apparatus and the method for operating the test apparatus is characterized by the following: a signal processing unit decomposes a sampled signal or a time-delayed sampled signal into quadrature signal components, modulates these quadrature signal components with the corresponding quadrature signal components of a Doppler signature, and integrates the thus obtained modulated quadrature signal components to generate a sampled signal with an additional Doppler signature. As will be further shown later, superimposed modulation of the Doppler signature can be realized very easily based on this, relying only on basic mathematical operations and thus resulting in minimal latency, which is a significant advantage.

[0014] According to one evolution of the test apparatus and method described above, the signal processing unit is configured to derive orthogonal signal components from the Doppler signature, particularly by I / Q separation of the Doppler signature. Alternatively, the orthogonal signal components are pre-configured as the Doppler signature for the signal processing unit, and the information content of these various embodiments of the Doppler signature is the same with respect to describing a specific motion profile.

[0015] A further preferred embodiment of the above-described test apparatus and the method for operating the test apparatus is characterized by the following: the decomposition of a sampled signal or a time-delayed sampled signal into quadrature signal components is performed by I / Q separation, and the integration of the modulated quadrature signal component into an additionally Doppler-signed sampled signal is performed by I / Q synthesis. In the I / Q process described herein, during separation, the signal is decomposed into in-phase and quadrature components (hence I / Q), and phase information can then be obtained from these components. Conversely, during the synthesis of the I / Q components, a signal having a specific phase position can be generated.

[0016] A particularly preferred embodiment of the above-described test apparatus and the method for operating the test apparatus is configured as follows: the decomposition of a sampled signal or a time-delayed sampled signal into quadrature signal components is performed by a 90° phase shift of the sampled signal or the time-delayed sampled signal, and / or the modulation of the quadrature signal components is performed by multiplication with the corresponding quadrature signal components of a Doppler signature, and / or the integration of the modulated quadrature signal components into an additionally Doppler-signed sampled signal is performed by the addition of the modulated quadrature signal components. The 90° phase shift of the sampled signal or the time-delayed sampled signal can be implemented, for example, by a Hilbert transform implemented as a digital FIR filter. Overall, this embodiment can be implemented very simply, and since only basic operations (multiplication, addition) are actually used, this embodiment involves only minimal latency, ideally constant latency, and this also applies to the digital implementation of the FIR filter for the 90° phase shift.

[0017] Although the apparatus and method according to the present invention have always been described in common, it is important to clarify once again that this method is computer-implemented and used to operate a test apparatus for testing electromagnetically operated distance sensors. To implement this method, the test apparatus includes a receiving member that receives free-space electromagnetic waves as a received signal, a radiating member that emits an electromagnetic output signal, an analog-to-digital converter, a signal processing unit, and a digital-to-analog converter. During the simulation operation, the received signal or a received signal derived from this received signal is converted into a sampled signal by the analog-to-digital converter, this sampled signal is time-delayed by the signal processing unit using a preset time delay so that a time-delayed sampled signal is generated, the time-delayed sampled signal is converted into a simulated reflected signal by the digital-to-analog converter, and the simulated reflected signal or a simulated reflected signal derived from this simulated reflected signal is emitted as an output signal via the radiating member. To easily mimic the specific motion profile of the reflective object being simulated, this method is configured as follows. In other words, the signal processing unit modulates a sampled signal or a time-delayed sampled signal by superimposing a Doppler signature, which can be pre-configured as the specific motion profile of the reflective object being simulated. Furthermore, the time-delayed sampled signal with the additionally Doppler signature is converted into a simulated reflected signal using a digital-to-analog converter. Detailed embodiments of the method steps have been described in detail above, mostly in relation to the signal processing unit. The term "signal processing unit" should be understood as a functional unit. A signal processing unit includes all the components necessary to fulfill the function that is considered to belong to the signal processing unit. Whether it is one part or multiple parts is not important.

[0018] Furthermore, the present invention relates to a computer program that, when executed by a signal processing unit of a test apparatus for testing an electromagnetic wave-operated distance sensor, includes instructions causing the signal processing unit to perform the above-described method for operating the test apparatus.

[0019] For more details, there are numerous possibilities for further developing the test apparatus and method according to the present invention as described in the independent claims. These are shown in relation to the drawings in the following figures. [Brief explanation of the drawing]

[0020] [Figure 1] This diagram schematically shows a test apparatus known from the prior art for testing distance sensors that operate using electromagnetic waves, as well as a corresponding method for operating such a test apparatus. [Figure 2] This figure schematically illustrates one embodiment of a test apparatus capable of performing superimposed modulation of Doppler signatures and a method for operating this test apparatus. [Figure 3] This figure schematically illustrates another embodiment of a test apparatus capable of performing superimposed modulation of Doppler signatures and a method for operating this test apparatus. [Figure 4] This figure schematically illustrates another embodiment of a test apparatus capable of performing superimposed modulation of a Doppler signature by decomposing a sampled signal into quadrature signal components, and a method for operating this test apparatus. [Figure 5] This figure schematically illustrates another embodiment of a test apparatus capable of performing superimposed modulation of a Doppler signature, and a method for operating this test apparatus, in which a signal processing unit derives quadrature signal components from the Doppler signature. [Figure 6] This figure schematically illustrates another embodiment of a test apparatus capable of performing superimposed modulation of Doppler signatures, and a method for operating the test apparatus, wherein superimposed modulation of Doppler signatures is performed exclusively by addition and multiplication. [Figure 7]This diagram schematically illustrates the realization and operation of superimposed modulation of Doppler signatures, based on a simple example. [Modes for carrying out the invention]

[0021] Figures 1 to 7 show a test apparatus 1 for testing an electromagnetic wave-operated distance sensor 2 and a corresponding method 10 for operating the test apparatus 1, in various excerpts, embodiments, and degrees of detail. The drawings do not distinguish between showing only the test apparatus 1 and showing only the method 10, and since method 10 is carried out in the test apparatus 1 by the elements of the test apparatus 1, such a distinction would not be meaningful.

[0022] Figure 1 shows the overall configuration for testing the distance sensor 2 under test. The distance sensor 2 emits free-space electromagnetic waves in the direction of the test device 1, and simulated electromagnetic reflection signals S are emitted from the test device 1. TX To receive the free-space wave emitted from the distance sensor 2, the test apparatus 1 has a receiving member 3 and simulates the electromagnetic reflection signal S. TX To emit radiation, the test device 1 has a radiating member 4. Although the distance sensor 2 itself does not belong to the test device 1, it is still important to understand how the test device 1 works in cooperation with the distance sensor 2.

[0023] The device we are considering here is Test Device 1, in which signal processing is implemented digitally, that is, implemented as a sampling system. In this respect, the received signal S RX The received signal S' is derived by down-converting it using input mixer 8. RX However, it is sampled by the analog-to-digital converter 6. Sampling signal S sample The signal is led via the signal processing unit 5, and in this case, with respect to the signal processing unit 5, there is a time delay t delay,soll This can be set in advance. Therefore, the time-delayed sampling signal S sample,simso that the input signal of the signal processing unit 5, i.e., the sampling signal S, is generated sample is time-delayed (11). Next, the time-delayed sampling signal S sample,sim is converted by the digital-to-analog converter 7 into a simulated analog reflection signal S sim and remixed by the output mixer 9 to generate the required transmission frequency. Then, the derived simulated reflection signal S’ sim is radiated via the radiating member 4. The received signal S RX is down-converted to an intermediate frequency lower than that, and the simulated reflection signal S sim is up-converted to the required transmission frequency higher than that, which is optional. This enables digital signal processing at a lower sampling rate and a lower clock rate than would be required during signal processing if the original reception frequency of the received signal S RX were its original reception frequency.

[0024] In FIG. 1, it is shown that the time delay t delay,soll to be achieved is supplied to the signal processing unit 5 as information. In the test apparatus 1 illustrated here, the technical implementation of how to accurately supply this information to the signal processing unit 5 is not important. Generally, the presetting for the time delay to be adjusted will come from the ambient simulator, which simulates the scene of the object to be simulated including the surrounding objects and prepares the corresponding position information, velocity information, and / or acceleration information of the surrounding objects. For example, if it is known that the distance from the object to be simulated to the distance sensor of the test object is 30 m, the corresponding time delay is calculated considering the speed of light as the signal propagation time of the electromagnetic wave, and is preset as the time delay t delay,soll .

[0025] In FIGS. 2 to 7, for the purpose of being able to simulate a reflecting object having an arbitrary motion pattern, and in particular for the purpose of being able to simulate a reflecting object having a complex motion pattern such as a pedestrian, the simulated reflection signal Ssim How to do Doppler signature S doppler This indicates whether additional measures can be taken.

[0026] In all embodiments shown in Figures 2 to 7, this means that the signal processing unit 5 processes the sampled signal S sample or time-delayed sampling signal S sample,sim Furthermore, a Doppler signature S can be pre-set as the unique motion profile of the reflective object being simulated. doppler This is achieved by superimposing and modulating (12). Subsequently, the Doppler signature S doppler A time-delayed sampling signal S that has been treated sample,sim However, the digital-to-analog converter 7 simulates the reflected signal S sim It will be converted.

[0027] In the case of the test apparatus 1 and method 10 shown in Figure 2, the signal processing unit 5 first processes the sampled signal S sample Doppler Signature S doppler The following is modulated by superimposing (12), followed by the Doppler signature S doppler The sampled signal S after the treatment sample The time-delayed sampling signal S sample,sim A pre-set time delay t is set so that it is generated. delay,soll A time delay is introduced using (11). In contrast, in the case of the test apparatus 1 shown in Figure 3, the signal processing unit 5 first processes the sampling signal S sample A pre-set time delay t delay,soll The time delay is applied using (11), followed by the Doppler signature S doppler The two are superimposed and modulated (12), and in this way the Doppler signature S is added. doppler A time-delayed sampling signal S that has been treated sample,sim This is generated.

[0028] Figure 4 shows the following: That is, the signal processing unit 5 processes the sampled signal S sample or time-delayed sampling signal Ssample,sim (The order is not important), the orthogonal signal components S sin ,S cos Decompose into (13), and the orthogonal signal component S sin ,S cos However, Doppler signature S doppler The corresponding orthogonal signal component S doppler,sin ,S doppler,cos The modulated quadrature signal component S obtained in this way is modulated by (12). sin,mod ,S cos,mod (14) is integrated, and additionally, the Doppler signature S doppler The sampled signal S after the treatment sample,sim This is generated.

[0029] Various possibilities exist for achieving orthogonal signal decomposition. In the example relating to the test apparatus 1 and method 10 shown in Figure 4, the orthogonal signal component S sin ,S cos Sampling signal S to sample or time-delayed sampling signal S sample,sim Decomposition 13 is performed by I / Q separation, and additionally Doppler signature S doppler The sampled signal S after the treatment sample,sim The modulated quadrature signal component S sin,mod ,S cos,mod The integration of these signals is performed by I / Q synthesis. As already mentioned in the general explanation section, this is a well-known signal decomposition into common-mode and quadrature components, and is nothing other than signal synthesis from these quadrature signal components.

[0030] In the example of the test apparatus 1 and method 10 shown in Figure 5, the signal processing unit 5 processes the Doppler signature S doppler From the orthogonal signal component S doppler,sin ,S doppler,cos Here, we have the Doppler signature S doppler This is derived by I / Q separation. In contrast, in the case of test apparatus 1 and method 10 shown in Figure 4, the orthogonal signal component S doppler,sin ,S doppler,cos The Doppler signature S doppler It is pre-configured as such.

[0031] Figure 6 shows a particularly preferred embodiment of the test apparatus 1 and method 10, characterized by the following: In this case, the orthogonal signal component S sin ,S cos Sampling signal S to sample or time-delayed sampling signal S sample,sim Decomposition 13 is the sampling signal S sample or time-delayed sampling signal S sample,sim This is done by a 90° phase shift. Furthermore, the quadrature signal component S sin ,S cos Modulation 12 is Doppler signature S doppler The corresponding orthogonal signal component S doppler,sin ,S doppler,cos This is achieved by multiplication with, and additionally, the Doppler signature S doppler The sampled signal S after the treatment sample,sim The modulated quadrature signal component S sin,mod ,S cos,mod The integration of 14 results in the modulated quadrature signal component S sin,mod ,S cos,mod This is done by addition. In other words, only basic mathematical operations that can be performed relatively quickly are used. This also applies to a 90° shift of the sampled signal, if this is done by a Hilbert transform realized using, for example, a digital FIR filter (addition, multiplication, dead time).

[0032] Figure 7 shows the sampling signal S. sample or time-delayed sampling signal S sample,sim Doppler signature S to doppler A concrete implementation of the superimposed modulation 12 is shown based on a simple example. These processes can be carried out, for example, using the test apparatus shown in Figure 6. Sampling signal S sample The frequency is f C This is a harmonic oscillation having the Doppler signature S doppler This leaves traces of the Doppler signature, which shifts the frequency to even higher frequencies f Dwill be caused. Above FIG. 7, the amplitude spectrum of the sampling signal S sample is shown. In this case, for the purpose of keeping the description as concise as possible, it is always processed in a time-continuous notation here. Therefore, under this prerequisite, the sampling signal S sample is described as follows. That is, S sample =A * cos(2π * f C * t)

[0033] The real signal has signal components at positive and negative frequencies in the complex frequency spectrum or amplitude spectrum. In the case of this simple example, at the frequency f C with an amplitude A. For this, refer to the upper part of FIG. 7.

[0034] The decomposition 13 of the sampling signal S into the quadrature signal components S sin , S cos is performed by a 90° phase shift of the sampling signal S sample , which is not shown in detail. Therefore, as a result, it is as follows. That is, S cos =A * cos(ω C * sin * t-π / 2) S<00001​​​​​​​​​​​​​​​​​​​​​​doppler,cos =C / A * cos(ω D * t + π / 2) S doppler,sin =C / A * cos(ω D * t)

[0036] Thus, the orthogonal signal component S sin ,S cos After modulation 12, Doppler signature S doppler The corresponding orthogonal signal component S doppler,sin ,S doppler,cos Multiplication with the following signal is produced: That is, S cos,mod =C * cos(ω C * t-π / 2) * cos(ω D * t + π / 2) S sin,mod =C * cos(ω C * t) * cos(ω D * t)

[0037] Additionally, Doppler signature S doppler The sampled signal S after the treatment sample,sim The modulated quadrature signal component S sin,mod ,S cos,mod The integration of 14 results in the modulated quadrature signal component S sin,mod ,S cos,mod This is done by addition. That is, S sample,sim =C * [cos(ω C * t) * cos(ω D * t)+cos(ω C * t-π / 2) * cos(ω D * (t + π / 2) =C* [cos(ω C * t) * cos(ω D * t)-sin(ω C * t) * sin(ω D * t) =C * cos({ω C +ω D} * t)

[0038] Accordingly, any other arbitrary Doppler signature S doppler Using a very simple method, the sampling signal S sample or time-delayed sampling signal S sample,sim It can be modulated by superimposing it (12). [Explanation of Symbols]

[0039] 1. Test apparatus 2. Distance Sensor 3 Receiving member 4 Radiating members 5. Signal Processing Unit 6. Analog / Digital Converter 7. Digital-to-Analog Converter 8-input mixer 9 Output Mixer 10 ways 11-hour delay 12. Superimposed Modulation of Doppler Signatures 13 Decomposition into orthogonal signal components 14 Integration of Modulated Quadrature Signal Components 15. Derivation of orthogonal signal components from Doppler signatures S RX Received signal S' RX Received signal S RX The received signal derived from S TX Output signal S sample Sampling signal t delay,sollPre-configurable time delay S sample,sim Time-delayed sampled signals, and in some cases, time-delayed sampled signals with additional Doppler signatures. S sim Simulated reflected signal S' sim Derived simulated reflected signal S doppler Doppler signature S sin ,S cos Orthogonal signal components of a sampled signal or a time-delayed sampled signal S doppler,sin S doppler,cos Quadrature signal components of a Doppler signature S sin,mod S cos,mod Modulated quadrature signal components

Claims

1. A test apparatus (1) for testing a distance sensor (2) that operates by electromagnetic waves, wherein the test apparatus (1) receives a free-space electromagnetic wave as a received signal (S ＲＸ ), and includes a receiving member (3) and a radiating member (4) that radiates an electromagnetic output signal (S ＴＸ ). During the simulation operation, the received signal (S ＲＸ ), or the received signal (S ＲＸ )-derived received signal (S' ＲＸ ), is converted by an analog / digital converter into a sampling signal (S ｓａｍｐｌｅ ), and the sampling signal (S ｓａｍｐｌｅ ) is time-delayed by a signal processing unit (5) using a presettable time delay (t ｓａｍｐｌｅ，ｓｉｍ ) so that a time-delayed sampling signal (S ｄｅｌａｙ，ｓｏｌｌ ) is generated (11). The time-delayed sampling signal (S ｓａｍｐｌｅ，ｓｉｍ ) is converted by a digital / analog converter into a simulated reflection signal (S ｓｉｍ ). The simulated reflection signal (S ｓｉｍ ), or the simulated reflection signal (S ｓｉｍ )-derived simulated reflection signal (S’ ｓｉｍ ) is radiated as an output signal (S ＴＸ ) through the radiating member (4) in the test apparatus (1). The signal processing unit (5) superimposes and modulates (12) a Doppler signature (S ｓａｍｐｌｅ ) or the time-delayed sampling signal (S ｓａｍｐｌｅ，ｓｉｍ ) with a Doppler signature (S ｄｏｐｐｌｅｒ ) that can be preset as a unique motion profile of a reflection object to be simulated, Additionally, the time delay sampling signal (S ｄｏｐｐｌｅｒ ), to which the Doppler signature (S ｓａｍｐｌｅ，ｓｉｍ ) is applied, is converted by the digital / analog converter into the simulated reflection signal (S ｓｉｍ ). A test device (1).

2. The signal processing unit (5) first superimposes and modulates (12) the Doppler signature (S ｓａｍｐｌｅ ) on the sampling signal (S ｄｏｐｐｌｅｒ ), and then delays (11) the sampling signal (S ｓａｍｐｌｅ ) with the applied Doppler signature using the preset time delay (t ｓａｍｐｌｅ，ｓｉｍ ) so that the time delay sampling signal (S ｄｅｌａｙ，ｓｏｌｌ ) is generated. Alternatively, the signal processing unit (5) first delays (11) the sampling signal (S ｓａｍｐｌｅ ) using the preset time delay (t ｄｅｌａｙ，ｓｏｌｌ ), and then superimposes and modulates (12) the Doppler signature (S ｓａｍｐｌｅ ) on the sampling signal (S ｄｏｐｐｌｅｒ ), and in this way additionally generates the time delay sampling signal (S ｄｏｐｐｌｅｒ ) with the applied Doppler signature (S ｓａｍｐｌｅ，ｓｉｍ ). The test device (1) according to Claim 1.

3. The signal processing unit (5) processes the sampling signal (S ｓａｍｐｌｅ ) or the time-delayed sampling signal (S ｓａｍｐｌｅ，ｓｉｍ ) into the orthogonal signal component (S ｓｉｎ , S ｃｏｓ ) (13), and the orthogonal signal components (S ｓｉｎ , S ｃｏｓ ) to the Doppler signature (S ｄｏｐｐｌｅｒ ) corresponding orthogonal signal components (S ｄｏｐｐｌｅｒ，ｓｉｎ , S ｄｏｐｐｌｅｒ，ｃｏｓ ) (12), and the modulated quadrature signal component (S ｓｉｎ，ｍｏｄ , S ｃｏｓ，ｍｏｄ ) and additionally combine (14) the Doppler signature (S ｄｏｐｐｌｅｒ The sampling signal (S ｓａｍｐｌｅ，ｓｉｍ ), The test device (1) according to Claim 1.

4. The signal processing unit (5) derives (15) the orthogonal signal components (S ｄｏｐｐｌｅｒ ), S ｄｏｐｐｌｅｒ，ｓｉｎ , S ｄｏｐｐｌｅｒ，ｃｏｓ ) from the Doppler signature (S ｄｏｐｐｌｅｒ ), in particular by I / Q separation of the Doppler signature (S ｄｏｐｐｌｅｒ，ｓｉｎ ), S ｄｏｐｐｌｅｒ，ｃｏｓ ), or the orthogonal signal components (S ｄｏｐｐｌｅｒ ) are preset for the signal processing unit (5) as the Doppler signature (S ). The test device (1) according to Claim 3.

5. Orthogonal signal components (S ｓｉｎ , S ｃｏｓ ) of the sampling signal (S ｓａｍｐｌｅ ) or the time-delayed sampling signal (S ｓａｍｐｌｅ，ｓｉｍ ) is decomposed (13) by I / Q separation, and additionally, the integrated (14) of the modulated orthogonal signal components (S ｄｏｐｐｌｅｒ ) on the sampling signal (S ｓａｍｐｌｅ，ｓｉｍ ) to which the Doppler signature (S ｓｉｎ，ｍｏｄ , S ｃｏｓ，ｍｏｄ ) is applied is performed by I / Q synthesis. The test device (1) according to Claim 3.

6. The orthogonal signal component (S ｓｉｎ , S ｃｏｓ ) to the sampling signal (S ｓａｍｐｌｅ ) or the time-delayed sampling signal (S ｓａｍｐｌｅ，ｓｉｍ ) is decomposed into the sampling signal (S ｓａｍｐｌｅ ) or the time-delayed sampling signal (S ｓａｍｐｌｅ，ｓｉｍ ) and / or the quadrature signal component (S ｓｉｎ , S ｃｏｓ ) modulation (12) of the Doppler signature (S ｄｏｐｐｌｅｒ ) corresponding orthogonal signal components (S ｄｏｐｐｌｅｒ，ｓｉｎ , S ｄｏｐｐｌｅｒ，ｃｏｓ ) and / or additionally by multiplication with the Doppler signature (S ｄｏｐｐｌｅｒ The sampling signal (S ｓａｍｐｌｅ，ｓｉｍ ) to the modulated quadrature signal component (S ｓｉｎ，ｍｏｄ , S ｃｏｓ，ｍｏｄ ) is integrated (14) to obtain the modulated quadrature signal components (S ｓｉｎ，ｍｏｄ , S ｃｏｓ，ｍｏｄ ) The test device (1) according to Claim 3.

7. A computer-implemented method (10) for operating a test device (1) for testing a distance sensor (2) operated by electromagnetic waves, The test device receives a free-space electromagnetic wave as a received signal (S ＲＸ ), and includes a receiving member (3), a radiating member (4) that radiates an electromagnetic output signal (S ＴＸ ), an analog / digital converter (6), a signal processing unit (5), and a digital / analog converter (7). During the simulation operation, the received signal (S ＲＸ ), or the received signal (S ＲＸ ), the derived received signal (S’ ＲＸ ), is converted into a sampling signal (S ｓａｍｐｌｅ ) by the analog / digital converter, and the sampling signal (S ｓａｍｐｌｅ ) is time-delayed (11) by the signal processing unit (5) using a presettable time delay (t ｓａｍｐｌｅ，ｓｉｍ ｄｅｌａｙ，ｓｏｌｌ ) so that a time-delayed sampling signal (S ｓａｍｐｌｅ，ｓｉｍ ) is generated. The time-delayed sampling signal (S ｓｉｍ ) is converted into a simulated reflection signal (S) by the digital / analog converter. The simulated reflection signal (S ｓｉｍ ), or the simulated reflection signal (S ｓｉｍ )-derived simulated reflection signal (S' ｓｉｍ ) is output as an output signal (S ＴＸ ) and radiated through the radiating member (4) in a method (10) The signal processing unit (5) superimposes and modulates (12) the sampling signal (S ｓａｍｐｌｅ ) or the time-delayed sampling signal (S ｓａｍｐｌｅ，ｓｉｍ ) with a Doppler signature (S ｄｏｐｐｌｅｒ ) that can be preset as a unique motion profile of a reflection object to be simulated, Additionally, the time-delay sampling signal (S ｄｏｐｐｌｅｒ ), to which the Doppler signature (S ｓａｍｐｌｅ，ｓｉｍ ) has been applied, is converted by the digital / analog converter (7) into the simulated reflection signal (S ｓｉｍ ). Method (10).

8. The signal processing unit (5) is configured to perform the method steps described in the characteristic part of at least one of Claims 2 to 6 during operation of the signal processing unit (5). The method (10) according to Claim 7.

9. A computer program, including instructions that cause the signal processing unit (5) of a test device (1) for testing a distance sensor (2) operated by electromagnetic waves to perform the method (10) according to Claim 7 when the computer program is executed by the signal processing unit (5). Computer program.

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