Method and system for simulating an electromagnetic environment within an anechoic chamber

Abstract

The invention provides a method and system for simulating an electromagnetic environment within an anechoic chamber. A method for simulating an electromagnetic environment (EME) within an anechoic chamber, comprising the steps of: receiving, by a first receiving unit, an input signal outside the anechoic chamber; generating, by a signal generating unit, a simulation signal based on the input signal; transmitting, by a transmitting unit, the simulation signal inside the anechoic chamber to simulate the EME; receiving, by a second receiving unit, the simulation signal inside the anechoic chamber; and adjusting, by the signal generating unit, the simulation signal generated by the signal generating unit based on the simulation signal received by the second receiving unit.

Description

TECHNICAL FIELD

[0001] The present invention relates to electromagnetic compatibility (EMC) and to testing devices by radio frequency (RF) signals or electromagnetic radiation. In particular, the present invention provides a controlled electromagnetic environment for such testing. More specifically, the present invention relates to simulating an electromagnetic environment within an anechoic chamber. BACKGROUND

[0002] In conventional solutions, devices under test (DUTs) are tested with respect to EMC. Typically, the DUTs are exposed to electromagnetic signals in an anechoic chamber. The electromagnetic signals are artificially generated by signal generators and can for example have a very high field strength. However, it is desirable to test DUTs in more complex scenarios, which is why artificially generated signals by signal generators are no longer sufficient. It is in particular desirable to test DUTs in an electromagnetic environment (EME) that corresponds to a real environment of the intended use case of the DUT.

[0003] For example, US 2018 / 0306904 A1 discloses a system for testing an integrated radar system. However, this solution is not able to provide complex electromagnetic signals, which are necessary for an effective EMC test, as described above. SUMMARY

[0004] It is therefore an object of the present invention to provide a method for testing a device that can simulate a real-world EME within an anechoic chamber. Furthermore, it is an object to provide a corresponding system and computer program.

[0005] This object is solved by the features of the method of the first independent claim and the features of the system of the second independent claim. Furthermore, this object is solved by the features of the related computer program product. The dependent claims contain further improvements.

[0006] An innovative method for simulating an electromagnetic environment (EME) within an anechoic chamber comprises the following steps: receiving an input signal by a first receiving unit outside the anechoic chamber; generating a simulation signal by a signal generating unit based on the input signal; transmitting the simulation signal by a transmitting unit inside the anechoic chamber to simulate the EME; and adjusting the simulation signal generated by the signal generating unit based on the simulation signal transmitted by the transmitting unit by the signal generating unit.

[0007] This is beneficial because, for example, the RF baseband signal (which can comprise an in-phase component and a quadrature component) (i.e. the input signal of the method) can be captured and recorded. Based on the recorded signal, a test system can be calibrated for testing using a wideband jamming signal of different bandwidths. Such a test system, which can be controlled and automated based on the recorded signal, can for example comprise an RF vector generator, an in-phase component and a quadrature component baseband recorder, an RF spectrum analyzer, an RF switch unit, a turntable, an antenna mast and an RF power amplifier. The recorded signal can be managed, for example with respect to center frequency, sampling rate, reference level and recording time. The invention also allows saving and extracting waveform files based on the input signal, transmitting waveform files and playing back real signals from a waveform file based signal generator. Furthermore, EME waveform playback similarity signature evaluation can be performed with the recorded traces (i.e. the input signal). Likewise, frequency response adjustment can be performed to meet the field strength required for testing in the test system.

[0008] That is, the method according to the invention allows to systematically, objectively and safely simulate the EME signal impact of real world scenarios inside the anechoic chamber.

[0009] Since the characteristics of EME jamming signals in the real world comprise narrowband signals or / and wideband signals that vary along time, the invention ensures that these complex signals can be reproduced inside the anechoic chamber by the emission unit in high similarity to the recorded signals of defined bandwidths from the environment (i.e. the input signal of the method).

[0010] In particular, the adjustment of the simulated signal generated by the signal generation unit based on the simulated signal emitted by the emission unit allows to calibrate the test system to produce test signals with the required field strength in order to ensure the repeatability of the test signals. This also ensures the safe operation of the test system, especially when producing high field strength signals. This is also beneficial because waveform playback similarity signatures can be evaluated to further adapt the simulated EME to real world scenarios recorded outside the anechoic chamber. Likewise, RF signal adjustment (adjustment of the signal of the simulated EME inside the anechoic chamber) can be performed in order to reproduce the same waveforms and achieve similar jamming effects as in the recorded real world scenarios.

[0011] In particular, the simulation (i.e. the generation of the simulated signal) comprises generating the simulated signal by means of a signal generator, wherein the simulated signal corresponds to the input signal. Thereby, the input signal (which is for example recorded outside the anechoic chamber) is reproduced inside the anechoic chamber. Thereby, the simulated signal compensates for effects due to the characteristics of the anechoic chamber, for example interference effects. That is, the simulated signal emitted inside the anechoic chamber produces the same EME as the EME (represented by the input signal) that exists outside the anechoic chamber.

[0012] In particular, the input signal represents an EME present outside the anechoic chamber. In particular, the EME outside the anechoic chamber is present at a predetermined location at which the input signal is received.

[0013] In particular, the input signal comprises an electromagnetic signal and / or an electromagnetic waveform. In particular, the input signal comprises a narrowband signal, a baseband signal and / or a wideband signal. In particular, the input signal comprises a broadcast transmission, a radar radiation, an out-of-band signal, an ambient noise and / or an influence from other transmitters. In particular, the input signal comprises a radio frequency baseband signal. In particular, the radio frequency baseband signal comprises an in-phase component and / or a quadrature component.

[0014] In particular, the analog signal comprises an electromagnetic signal and / or an electromagnetic waveform. In particular, the analog signal comprises a narrowband signal, a baseband signal and / or a wideband signal. In particular, the analog signal comprises a broadcast transmission, a radar radiation, an out-of-band signal, an ambient noise and / or an influence from other transmitters. In particular, the analog signal comprises a radio frequency baseband signal. In particular, the radio frequency baseband signal comprises an in-phase component and / or a quadrature component.

[0015] In particular, the device under test DUT can be placed inside the anechoic chamber.

[0016] In particular, the anechoic chamber is a room designed to completely absorb reflections of electromagnetic waves. In particular, the anechoic chamber refers to a reflection-free, echo-free and / or anechoic.

[0017] In particular, receiving the input signal by the first receiving unit comprises recording the input signal (e.g. by the first receiving unit or by the signal generation unit). The recorded signal can have an arbitrary length. In particular, the method further comprises generating the analog signal by the signal generation unit based on the recorded input signal.

[0018] In particular, the signal generation unit comprises a signal amplification unit.

[0019] In particular, adjusting the analog signal comprises applying a Fast Fourier Transformation, FFT, to the input signal and / or to the analog signal.

[0020] In particular, the transmitting unit comprises a transmitting circuitry and / or an antenna. In particular, the first receiving unit comprises a first receiving circuitry and / or an antenna. In particular, the second receiving unit comprises a second receiving circuitry and / or an antenna.

[0021] Advantageously and preferably, the method further comprises the steps of receiving the analog signal by the second receiving unit inside the anechoic chamber and adjusting the analog signal generated by the signal generation unit based on the analog signal received by the second receiving unit by the signal generation unit.

[0022] In particular, the second receiving unit comprises a receiving antenna.

[0023] Advantageously and preferably, the method further comprises the steps of analyzing, by the spectrum analyzer, the analog signal received by the second receiving unit to obtain an analysis result, and adjusting, by the signal generating unit, the analog signal generated by the signal generating unit based on the analysis result.

[0024] Advantageously and preferably, the method further comprises the step of performing a frequency response correction based on the input signal and / or the analog signal and / or the analysis result to adjust the analog signal.

[0025] In particular, the frequency response correction is based on the SMW-K544 algorithm or a similar algorithm.

[0026] In particular, the frequency response correction is performed in the signal generating unit and / or the spectrum analyzer. In particular, the frequency response correction is performed in the signal generating unit and / or the spectrum analyzer by means of test software.

[0027] Advantageously and preferably, the input signal comprises a signal in the range from 100 kHz to 60 GHz, preferably in the range from 80 MHz to 1 GHz.

[0028] Advantageously and preferably, the method further comprises the step of performing a waveform similarity test based on the input signal and / or the analog signal generated by the signal generating unit and / or the analog signal received by the second receiving unit and / or the analysis result.

[0029] In particular, the waveform similarity test comprises converting at least one of the above signals or results into the frequency domain for correction and amplitude adjustment.

[0030] In particular, the waveform similarity test is performed in the signal generating unit and / or the spectrum analyzer.

[0031] In particular, the method further comprises the step of determining a performance of the EME simulation based on the result of the waveform similarity test.

[0032] In particular, the performance is determined in the signal generating unit and / or the spectrum analyzer.

[0033] Advantageously and preferably, the first receiving unit is attached to a mobile unit, and the method further comprises the step of receiving the input signal during a test drive of the mobile unit.

[0034] In particular, the mobile unit can be a car, a truck, an airplane, a helicopter, a drone, a ship, a pedestrian, etc. In particular, the mobile unit can be driven by a person and / or can be self-driving.

[0035] Advantageously and preferably, the input signal and / or the analog signal comprises a fading component.

[0036] A system for simulating an electromagnetic environment (EME) within an anechoic chamber, comprising: a first receiving unit configured to receive an input signal outside the anechoic chamber; a signal generating unit configured to generate an analog signal based on the input signal; a transmitting unit configured to transmit the analog signal within the anechoic chamber to simulate the EME; wherein the signal generating unit is further configured to adjust the analog signal generated by the signal generating unit based on the analog signal transmitted by the transmitting unit.

[0037] Advantageously and preferably, the system is configured to receive the analog signal inside the anechoic chamber by a second receiving unit of the system; and to adjust the analog signal generated by the signal generating unit based on the analog signal received by the second receiving unit by the signal generating unit.

[0038] In particular, the second receiving unit comprises a receiving antenna.

[0039] Advantageously and preferably, the system further comprises a spectrum analyzer configured to analyze the analog signal received by the second receiving unit to obtain an analysis result, wherein the signal generating unit is further configured to adjust the analog signal generated by the signal generating unit based on the analysis result.

[0040] Advantageously and preferably, the system is further configured to perform a frequency response correction based on the input signal and / or the analog signal and / or the analysis result to adjust the analog signal.

[0041] In particular, the frequency response correction is performed in the signal generating unit and / or the spectrum analyzer. In particular, the frequency response correction is performed in the signal generating unit and / or the spectrum analyzer by means of test software.

[0042] Advantageously and preferably, the input signal comprises a signal in the range from 100 kHz to 60 GHz, preferably in the range from 80 MHz to 1 GHz.

[0043] Advantageously and preferably, the system is further configured to perform a waveform similarity test based on: the input signal; and the analog signal generated by the signal generating unit and / or based on the analog signal received by the second receiving unit and / or based on the analysis result.

[0044] In particular, the waveform similarity test is performed in the signal generating unit and / or the spectrum analyzer.

[0045] In particular, the method further comprises a step of determining the performance of the EME simulation based on the result of the waveform similarity test.

[0046] In particular, the performance is determined in the signal generating unit and / or the spectrum analyzer.

[0047] Advantageously and preferably, the first receiving unit is attached to a mobile unit of the system, and the system is further configured to receive the input signal during a test drive of the mobile unit.

[0048] The system of the invention comprises the same advantages as the method of the invention.

[0049] The computer program product of the invention comprises the same advantages as the device of the invention.

[0050] The computer program product of the invention comprises the same advantages as the device of the invention. BRIEF DESCRIPTION OF DRAWINGS

[0051] Exemplary embodiments of the invention will now be further described, by way of example only, with reference to the accompanying drawings in which:

[0052] Figure 1 a schematic diagram illustrating a method according to an embodiment of the invention;

[0053] Figure 2 a schematic diagram illustrating a system according to an embodiment of the invention;

[0054] Figure 3 a schematic diagram illustrating an operational scenario according to the invention;

[0055] Figure 4 a further schematic diagram illustrating an operational scenario according to the invention;

[0056] Figure 5 a schematic diagram illustrating a signal processed by the invention. DETAILED DESCRIPTION

[0057] In the following, the functionality of embodiments of the method of the invention will be described based on Figure 1 The functionality of embodiments of the method of the invention will be described. Then, reference will be made to Figure 2 The structure and functionality of embodiments of the system of the invention will be described. In Figure 3 and Figure 4 In the following, an operational scenario according to the invention will be described. Figure 5 Exemplary diagrams of signals that can be used by the invention are shown, either as input signals or as simulation signals to simulate EME in an anechoic chamber.

[0058] Figure 1A method 100 for simulating an electromagnetic environment 201 within an anechoic chamber 202 is shown. As Figure 1 shown, the method 100 comprises the following steps: step 101 - receiving, by a first receiving unit 203, an input signal 204 outside the anechoic chamber 202; step 102 - generating, by a signal generating unit 205, a simulation signal 206 based on the input signal 204; step 103 - transmitting, by a transmitting unit 207, the simulation signal 206 inside the anechoic chamber 202 to simulate the EME 201; and step 104 - adjusting the simulation signal 206 generated by the signal generating unit 205 based on the simulation signal 206 transmitted by the transmitting unit 207.

[0059] In an optional and thus not shown in Figure 1 step, the simulation signal 206 can be received by a second receiving unit 208 inside the anechoic chamber 202. Then, the simulation signal 206 generated by the signal generating unit 205 is adjusted based on the simulation signal 206 received by the second receiving unit 208.

[0060] In another optional and thus not shown in Figure 1 step, the simulation signal 206 received by the second receiving unit 208 is analyzed by a spectrum analyzer 401 to obtain an analysis result. Then, the simulation signal 206 generated by the signal generating unit 205 is also adjusted based on the analysis result.

[0061] Figure 2 A system 200 according to an embodiment of the present application is shown. The system 200 is for simulating an electromagnetic environment 201 in an anechoic chamber 202.

[0062] To this end, the system 200 comprises a first receiving unit 203 configured to receive an input signal 204 outside the anechoic chamber 202. The system 200 further comprises a signal generating unit 205 configured to generate a simulation signal 206 based on the input signal 204. The signal generating unit 205 can optionally further comprise an amplifier for amplifying the simulation signal 206 before transmitting the simulation signal 206. The system 200 further comprises a transmitting unit 207 configured to transmit the simulation signal 206 inside the anechoic chamber 202. By transmitting the simulation signal 206 corresponding to the obtained (and possibly recorded) input signal inside the anechoic chamber, the EME 201 is simulated.

[0063] The signal generating unit 205 is further configured to adjust the analog signal 206 generated by the signal generating unit 205 based on the analog signal 206 emitted by the emitting unit 207. This provides a feedback loop according to which the analog signal 206 can be calibrated to provide a desired field strength as well as a different bandwidth of the interference signal as is the case in real world scenarios outside the anechoic chamber, which the system 200 will simulate inside the anechoic chamber.

[0064] Figure 2 A second receiving unit 208 of the system 200 is also shown, which is an optional part of the system 200. The analog signal 206 is received by the second receiving unit 208 inside the anechoic chamber 202. The second receiving unit 208 can comprise an antenna, for example. The analog signal 206 generated by the signal generating unit 205 is then adjusted based on the analog signal 206 received by the second receiving unit 208.

[0065] The system 200 can also comprise an optional spectrum analyzer, which is not shown in Figure 2 The spectrum analyzer can analyze the analog signal 206 received by the second receiving unit 208 to obtain an analysis result. The analog signal 206 generated by the signal generating unit 205 is then also adjusted based on the analysis result.

[0066] Figure 3 A schematic diagram of an operating scenario according to the present application is shown. However, Figure 3 only serves to illustrate the operating principle and therefore not all features described, for example in connection with Figure 1 or Figure 2 are shown. In particular, the processes shown in Figure 3 are shown twice, which is why some entities are shown twice.

[0067] As shown in Figure 3 , the input signal 204 is received outside the anechoic chamber 202. The analog signal 206 is generated based on the input signal 204 and then emitted by means of the emitting unit 207. Further calibration and adjustment of the analog signal 206 can also be performed based on the input signal 204 and based on the analog signal 206, and the adjusted analog signal 206 is output again by the emitting unit 207. As shown in Figure 3 , the analog signal 206 is applied to the DUT.

[0068] Figure 4 A schematic diagram of another operating scenario according to the present application is shown. However, Figure 4 only serves to illustrate the operating principle and therefore not all features described, for example in connection with Figure 1 or Figure 2 are shown.

[0069] like Figure 4 As shown, the first receiving unit 203 receives the input signal 204. Then, the signal generation unit 205 generates an analog signal 206 based on the input signal 204. Although in Figure 4 The signal generation unit 205 is shown as a separate entity, but it may also include an amplifier for amplifying the analog signal 206. The analog signal 206 is then provided to the transmitting unit 207, which transmits the analog signal 206 inside the anechoic chamber 202. Inside the anechoic chamber 202, the analog signal 206 is received by means of a second receiving unit 208. The received analog signal 206 is provided to a spectrum analyzer 401, which analyzes the received analog signal 206 and provides analysis results. Additionally, test software (such as software for frequency response correction and / or waveform similarity testing) may be applied to the received analog signal 206 and / or the analysis results. The received analog signal 206 and / or the analysis results are then provided to the signal generation unit 205, where the analog signal 206 provided by the signal generation unit 205 is adjusted based on the received analog signal 206 and / or based on the analysis results.

[0070] Figure 5 A schematic diagram of a signal processed by the present invention is shown. The signal shown may be included in input signal 204 and / or analog signal 206. Figure 5 The signal shown includes the frequency modulation signal FM1 in the typical spectrum of radio broadcast communication. Figure 5 The signal shown includes PTT2, a signal typical of the spectrum of a push-to-talk handheld radio. Figure 5 The signal shown includes signal LTE3 in the typical spectrum of an LTE user equipment (UE) or base station. That is, input signal 204 and / or analog signal 206 may include at least one component in the range of 100 kHz to 60 GHz, preferably in the range of 80 MHz to 1 GHz. In particular, additionally or alternatively, signal 204 and / or analog signal 206 may also include at least one component from 5G frequency range 2 (FR2), which includes a frequency band from 24.25 GHz to 52.6 GHz.

[0071] It is important to note that the system and method of the present invention correspond very closely. Therefore, everything described above regarding the system also applies to the method, and vice versa. Everything described in the specification and / or claimed in the claims and / or depicted in the drawings can be combined.

[0072] The application is not limited to the exemplary embodiments. All features described above or shown in the drawings can be combined in any advantageous way with each other.

Claims

1. A method (100) for emulating an electromagnetic environment (EME) (201) within an anechoic chamber (202), the method (100) comprising the steps of: - receiving (101) an input signal (204) by a first receiving unit (203) outside the anechoic chamber (202); - generating (102) an emulation signal (206) by a signal generating unit (205) based on the input signal (204); - transmitting (103) the emulation signal (206) by a transmitting unit (207) inside the anechoic chamber (202) to emulate the electromagnetic environment (201); and - adjusting the emulation signal (206) generated by the signal generating unit (205) based on the emulation signal (206) transmitted by the transmitting unit (207) by the signal generating unit (205), wherein the method (100) further comprises the steps of receiving the emulation signal (206) by a second receiving unit (208) inside the anechoic chamber (202); and adjusting the emulation signal (206) generated by the signal generating unit (205) based on the emulation signal (206) received by the second receiving unit (208) by the signal generating unit (205), wherein the method (100) further comprises the steps of analyzing the emulation signal (206) received by the second receiving unit (208) by a spectrum analyzer (401) to obtain an analysis result; and adjusting the emulation signal (206) generated by the signal generating unit (205) based on the analysis result by the signal generating unit (205), wherein the method (100) further comprises the steps of performing a waveform similarity test based on: based on the input signal (204), and based on the emulation signal (206) generated by the signal generating unit (205) and / or based on the emulation signal (206) received by the second receiving unit (208) and / or based on the analysis result; and determining a performance of the electromagnetic environment emulation based on a result of the waveform similarity test.

2. The method (100) of claim 1, further comprising the step of: Performing a frequency response correction based on the input signal (204) and / or the emulation signal (206) and / or the analysis result to adjust the emulation signal (206).

3. The method (100) of claim 1 or 2, wherein The input signal (204) and / or the emulation signal (206) comprises a signal in a range from 100 kHz to 60 GHz.

4. The method (100) according to claim 1 or 2, wherein The first receiving unit (203) is attached to a mobile unit, and the method (100) further comprises the step of receiving the input signal (204) during a test drive of the mobile unit.

5. The method (100) according to claim 1 or 2, wherein The input signal (204) and / or the emulation signal (206) comprises a fading component.

6. The method (100) of claim 3, wherein The input signal (204) and / or the emulation signal (206) comprises a signal in a range from 80 MHz to 1 GHz.

7. A system (200) for simulating an electromagnetic environment (EME) (201) within an anechoic chamber (202), wherein, The system (200) comprises: - a first receiving unit (203) configured to receive an input signal (204) outside the anechoic chamber (202); - a signal generating unit (205) configured to generate an analog signal (206) based on the input signal (204); and - a transmitting unit (207) configured to transmit the analog signal (206) inside the anechoic chamber (202) to emulate the electromagnetic environment (201); wherein the signal generating unit (205) is further configured to adjust the analog signal (206) generated by the signal generating unit (205) based on the analog signal (206) transmitted by the transmitting unit (207), wherein the system (200) is further configured to receive the analog signal (206) inside the anechoic chamber (202) by a second receiving unit (208) of the system (200); and to adjust the analog signal (206) generated by the signal generating unit (205) based on the analog signal (206) received by the second receiving unit (208) by the signal generating unit (205), wherein the system (200) further comprises a spectrum analyzer (401) configured to analyze the analog signal (206) received by the second receiving unit (208) to obtain an analysis result, wherein the signal generating unit (205) is further configured to adjust the analog signal (206) generated by the signal generating unit (205) based on the analysis result, wherein the system (200) is further configured to perform a waveform similarity test based on the input signal (204), and based on the analog signal (206) generated by the signal generating unit (205) and / or based on the analog signal (206) received by the second receiving unit (208) and / or based on the analysis result; and to determine a performance of the electromagnetic environment emulation based on a result of the waveform similarity test.

8. The system (200) according to claim 7, further configured to perform a frequency response correction based on the input signal (204) and / or the analog signal (206) and / or the analysis result to adjust the analog signal (206).

9. The system (200) according to claim 7 or 8, wherein, The input signal (204) and / or the analog signal (206) comprises a signal in a range from 100 kHz to 60 GHz.

10. The system (200) according to claim 7 or 8, wherein, The first receiving unit (203) is attached to a mobile unit of the system (200), and the system (200) is further configured to receive the input signal (204) during a test drive of the mobile unit.

11. The system (200) of claim 9, wherein, The input signal (204) and / or the analog signal (206) comprises a signal in a range from 80 MHz to 1 GHz.

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