Method and system for resolving distance and velocity of at least one object

Abstract

The present disclosure relates to a method (100) for resolving the distance and velocity of at least one object, the method comprising transmitting (101) a pair of scans. Further, the method comprises independently obtaining (102) a first time-domain signal and a second time-domain signal formed by reflections of the first and second electromagnetic waveforms in the scan pair, and determining (103) a beat frequency of a baseband signal for each obtained time-domain signal in the scan pair. Further, the method comprises determining (104) the velocity and distance of at least one object by linearly combining (a1) the beat frequencies of the obtained first and second signals of the scan pair to derive the velocity and distance of the single object. However, if the obtained signal is reflected from a plurality of objects, the determining step comprises linearly combining (b1) the beat frequencies obtained from the signal to derive a plurality of possible associations. Further, the method comprises transmitting (b2) a sequence of further scan pairs and identifying (b3) a correct association based on the sequence.

Description

Technical Field

[0001] The present disclosure relates to a method and system for resolving the range and velocity of at least one object. Background Art

[0002] Today's vehicles are equipped with radar devices, which are typically focused in a specific direction, such as the vehicle's direction of travel. Radar devices are required to operate within a predefined frequency band, with each radar occupying a significant portion of this band. Because conventional radar devices are easily blinded by interference within their operating band, even in moderately congested traffic conditions, the availability of the allocated frequency band can be highly patchy.

[0003] Therefore, vehicles with radar devices, especially in areas with moderate to large vehicle populations, are susceptible to interference. Currently, there are no suitable methods, systems, and radar devices that can effectively mitigate this interference risk without sacrificing basic radar performance characteristics, such as radar continuous availability, multi-target capability, range coverage, and velocity and speed resolution.

[0004] Existing technologies may only be effective when maintaining radar performance is not critical to vehicle safety. However, with the current increasing reliance on vehicle sensors, and especially with the advent of autonomous vehicles, maintaining radar performance is an absolute requirement.

[0005] In short, the methods, radar devices and systems in the prior art need to be improved to meet the current interference mitigation needs in road traffic. Summary of the Invention

[0006] It is therefore an object of the present disclosure to provide novel methods, systems, and electronic devices that can mitigate interference when resolving the distance and velocity of objects while allowing many users to be within the frequency band without any performance degradation.

[0007] The fundamental principle of interference-free operation between radars in the same frequency band is that the radars employ linearly scanned radar signals with the same scan rate. Therefore, these signals differ due to being transmitted at different times and will therefore never operate simultaneously at the same frequency. In some aspects, to provide a sufficient level of interference-free operation, a specific long scan time can be provided, as suggested by the present disclosure, so that the signal propagation time between potentially interfering radars is relatively small. Furthermore, signal start / end effects may cause interference, but the separation will be sufficiently large. For linearly scanned radars, target range and velocity can be measured using the so-called beat frequency of the radar response, which is a linear combination of the target's range and velocity. Because the beat frequency is a single value, range and velocity cannot be uniquely determined. In some aspects, a series of scans can be used, where the velocity causes a phase shift between these scans. The target's Doppler frequency, and therefore the velocity, is calculated from this phase shift. Once the velocity is resolved, the range is also determined.

[0008] However, the slow scan rate required to avoid interference is several orders of magnitude lower than the repetition rate required for phase measurement (and thus Doppler determination). Therefore, a different approach is needed to resolve this range-velocity ambiguity. As will be explained below, this object is achieved by the electronic device, system, and method defined in the appended claims.

[0009] The present disclosure relates to a (computer-implemented) method for resolving the range and velocity of at least one object, the method comprising the steps of simultaneously transmitting a first electromagnetic waveform and a second electromagnetic waveform, each electromagnetic waveform comprising a frequency modulated (preferably linear) chirp having a predetermined sweep time, the first electromagnetic waveform and the second electromagnetic waveform being counter-chirped, forming a so-called sweep pair. The method further comprises the steps of independently obtaining first and second time domain signals formed by reflections of the first and second electromagnetic waveforms in the sweep pair. The sweep pair may have been reflected from one or more objects (typically vehicles or other objects along a road).

[0010] The method further includes detecting / determining a beat frequency of a baseband signal of each acquired time-domain signal in the scan pair, and determining the speed and distance of the at least one object. If the acquired signals are reflected from a single object, the determining step includes linearly combining the beat frequencies of the first and second acquired signals of the scan pair to derive the speed and distance of the single object. Thus, based on the beat frequency values ​​in the two frequency bands, the resulting system of linear equations can be solved to determine the speed and distance of the at least one object.

[0011] Furthermore, if the signal obtained is reflected from multiple objects, the step of determining the target speed and distance (values) comprises linearly combining the beat frequencies obtained from the signal to derive a plurality of possible associations. In other words, the method comprises correlating any beat frequency of one frequency band with any beat frequency of another frequency band and deriving a plurality of range-speed pairs by solving the linear equations defined thereby. For P targets, the associations and thus the speed-distance pairs are P 2 , P is an integer > 0, and each association represents / indicates a possible target. Although P may refer to the number of actual objects / targets, P 2 associated indicator targets, where P 2 P associations may be erroneous. To remove these erroneous associations, the method further includes transmitting a (continuous) sequence of additional scan pairs. During this sequence, the beat frequency will change, corresponding to the change in object distance as the intrinsic velocity of each object changes. By re-correlating these changed beat frequencies, not only the changed distance can be calculated, but also the target distance at the time of the first scan.

[0012] If the association is correct, the calculated distance value remains constant from one scan to the next. Similarly, the calculated velocity value remains constant only for correct associations. Therefore, associations that cause distance and velocity deviations during consecutive scans are ignored, and the correct association is found. Note that the measurement requires establishing the beat frequency offset, not the phase offset. Therefore, unlike phase measurements, frequency measurements are insensitive to the sampling rate, and scanning can be performed at a slow rate consistent with interference mitigation. In summary, this method effectively allows the correct establishment of the distance and velocity of one or more objects.

[0013] During or before the determining step, the method may include the following steps: determining whether the acquired signal is reflected from a single object or from multiple objects. This may be performed in a variety of ways that will be understood by those skilled in the art.

[0014] In some aspects herein, at a center frequency of 50 GHz to 90 GHz, the predetermined sweep time is 2 to 3 milliseconds, preferably 2.25 to 2.75 milliseconds, and more preferably 2.5 milliseconds. With this selection, and while maintaining standard performance figures for today's radars, a large number of non-interfering radar devices (approximately 1,000) can occupy this frequency band.

[0015] Furthermore, in some aspects herein, each first electromagnetic waveform is located in a first frequency channel and each second electromagnetic waveform is located in a second frequency channel, wherein the first frequency channel and the second frequency channel are adjacent to each other.

[0016] Additionally, in some aspects herein, the method includes the step of identifying, by signal processing, the difference between distance values ​​obtained from associations in a sequence of scan pairs counted in the positive time direction and corresponding associations in a sequence of scan pairs counted in the negative time direction, starting at an arbitrarily selected time zero. The mean of the distance differences is zero only if the associations are correct, including both cases where the target moves at a constant speed or experiences a change in speed. Thus, the step of removing erroneous associations includes eliminating associations for which the distance difference estimates based on multiple scans are non-zero. The advantage of accepting speed changes makes the method useful in applications where acceleration or deceleration of a vehicle is critical, including situations where the vehicle may brake suddenly.

[0017] This method can be implemented using a computer algorithm that matches the range differences obtained from each scan to a linear progression model, since erroneous associations also follow such a linear progression path, albeit with a non-zero rate of increase in range differences. With each measurement, randomized by noise and measurement error, erroneous associations are removed because their rate of progression (estimated with increasing accuracy from ongoing measurements) is higher than the expected value of the range differences of the correct associations, which all fluctuate around a mean of zero. Proceeding in this manner, severely erroneous associations can be removed in the first few scans, reaching the limit of their resolvability when target separations eventually become smaller than the radar's resolution.

[0018] Furthermore, the scan number index is l=0, 1, ..., where the first scan l=0 is at an arbitrarily selected time. m(l), n(l) = 1, 2, ..., where m = 1, ..., P, n = 1, ..., P, and Arranged in ascending order of frequency value, m(l) and n(l) are the beat frequencies being tracked, taking into account that any frequency number m or n can be interchanged if the beat frequencies cross each other from one scan to the next (as can happen in a crowded situation with many targets moving at different rates). The range value for any beat frequency combination, and therefore representing a real or false target, is obtained as:

[0019]

[0020] Where c is the speed of light, B is the bandwidth, and f c is the center frequency, and τ is the sweep time for a single sweep. The distance difference is calculated as:

[0021]

[0022] According to the following formula:

[0023]

[0024] Where Δr is the distance between the associated targets, that is, for the true association, Usually, B / (4f c )=4%, and at the same time, it can be established Equal to or better than the radar resolution - for example, within 0.1m. From this, it can be seen that for targets with a separation greater than Δr = 1m, false associations can be eliminated within 28 scans (i.e., total registration time τ×28 = 0.07s, where the scan time τ = 2.5ms as mentioned above).

[0025] Further to the method, a computer-accessible storage medium is also provided herein, storing one or more programs configured to be executed by one or more control circuits of a vehicle, the one or more programs including instructions for executing the method of any aspect herein.

[0026] An electronic device including control circuitry is also provided. The electronic device may include modules for performing the methods described herein. The control circuitry of the electronic device may include an oscillator, at least one mixer, an up / down conversion module, an analog-to-digital converter, a digital-to-analog converter, a fast Fourier transform module, an amplifier, a filter, and other suitable circuitry. The electronic device also includes at least one transmitter and a receiver coupled to respective transmit and receive antenna arrays, each antenna array having multiple antenna elements. The electronic device may be referred to as a radar device.

[0027] Furthermore, a vehicle is provided, comprising an electronic device having control circuitry configured to perform the method according to any aspect herein. The vehicle may be a land vehicle, an aircraft, a spacecraft, or a watercraft. A stationary device is also provided, comprising an electronic device having control circuitry configured to perform the method according to any aspect herein. The stationary device may be a base station.

[0028] In some aspects of the method, a system is provided that includes a plurality of similar electronic devices (i.e., radar devices) performing a method according to any aspect herein, wherein each electronic device transmits a counter-chirp using one of a plurality of transmission channels, wherein adjacent channels in the plurality of transmission channels have a time delay relative to each other. The time delay may be, for example, 2 μs to 4 μs or any other suitable value. The number of channels may vary from 10 to 100 or 1000 channels, or even more than 1000 channels.

[0029] Generally, all terms used in the specification should be interpreted according to their ordinary meaning in the technical field, unless otherwise explicitly defined herein. All references to "a / the [element, device, component, means, step, etc.]" should be openly interpreted as referring to at least one instance of the element, device, component, means, step, etc., unless otherwise explicitly stated. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] These and other features and advantages of the present disclosure will now be further elucidated and described in more detail with reference to the accompanying drawings;

[0031] Figure 1 A method is schematically illustrated in the form of a flow chart;

[0032] Figure 2A A diagram depicting a scan pair is shown;

[0033] Figure 2B A graph depicting a linear combination of beat frequencies is shown;

[0034] Figure 3 shows a graph depicting linear combinations of beat frequencies for a number of possible associations;

[0035] Figure 4 An electronic device is schematically shown;

[0036] Figure 5A A system is schematically shown;

[0037] Figure 5B Schematically illustrates multiple radar devices utilizing the same frequency band;

[0038] Figure 6 Four plots are shown simulating the results of various aspects of the disclosure herein. DETAILED DESCRIPTION

[0039] Figure 1A method 100 for resolving the range and velocity of at least one object is schematically illustrated in flowchart form. The method includes the following steps: simultaneously transmitting a first electromagnetic waveform and a second electromagnetic waveform 101. Each electromagnetic waveform includes a frequency-modulated chirp with a predetermined sweep time, and the first electromagnetic waveform and the second electromagnetic waveform are counter-chirped, forming a sweep pair. Furthermore, the method 100 includes the following steps: independently obtaining a first signal and a second signal 102 formed by reflections of the first and second electromagnetic waveforms in the sweep pair. Furthermore, the method 100 includes detecting / determining a beat frequency of each received signal in the sweep pair 103. The method also includes the following steps: determining the velocity and range of the at least one object 104. Determination 104 can be performed by solving a system of linear equations for velocity and range based on the beat frequency of the first and second waveforms 104 of the at least one object. This can be performed through signal processing.

[0040] If the acquired signal is reflected from a single object, the determining step comprises linearly combining the beat frequencies of the acquired first and second signals of the a1 scan pair to deduce the speed and distance of the single object. The derivation can be performed by a system of equations or any other suitable type of calculation.

[0041] Therefore, if the signal obtained is reflected from multiple objects, the determination step includes linearly combining b1 the beat frequencies obtained from the signal to derive a number of possible associations, where for P targets the associations are P 2 , P is an integer greater than 1, and each association indicates a possible target. The method then includes transmitting b2 a sequence of additional scan pairs and identifying b3 a correct association based on the sequence. Therefore, a possible association is not necessarily a correct association. Therefore, the method derives a correct association based on the derived possible associations.

[0042] Figure 2A 1. A scan pair 20 is shown with frequency along the vertical axis and time along the horizontal axis. The scan pair includes a first electromagnetic waveform 20a and a second electromagnetic waveform 20b that are oppositely directed. Figure 2A As shown, the first waveform 20a may be an up-chirp and the second waveform 20b may be a down-chirp. The value B is the radar bandwidth.

[0043] Value F + and F - is the beat frequency of the corresponding chirp 20a, 20b. Thus, the beat frequency refers to the frequency difference between the echo and the transmitted up-chirp and down-chirp. In some aspects, the center frequency The predetermined scanning time may be between 50 GHz and 90 GHz, and may be between 2 and 3 milliseconds, preferably between 2.25 and 2.75 milliseconds, and more preferably 2.5 milliseconds. Figure 2AAs shown, each first electromagnetic waveform 20a is located in a first frequency channel, and each second electromagnetic waveform 20b is located in a second frequency channel. The first frequency channel and the second frequency channel are preferably adjacent to each other.

[0044] Figure 2A Also shown is the beat frequency F + and F - How it is generated as two different linear combinations of target distance and speed.

[0045] Figure 2B according to Figure 1 Method step a1 in FIG. 1 shows how the distance r and the speed v can be taken as Figure 2A The beat frequency F + and F - The solutions of the proposed linear equations are calculated by linear combinations of .

[0046] According to this calculation example, the range and velocity resolutions are determined based on a system of linear equations. The implicit range and velocity resolutions are derived from Figure 2B The disclosed formula, combined with the achievable resolution of the beat frequency, is expressed as:

[0047]

[0048] It should be noted that the values ​​0.15 m / s and 0.2 m are merely example values ​​used to illustrate calculations according to some aspects of the method 100 herein.

[0049] Figure 3 It is shown that when the signal is reflected from multiple objects, the beat frequencies are linearly combined, resulting in multiple possible correlations. Figure 3 Three targets are shown: 1, 2, and 3. Using symbolic mapping This may include matching a specific first or second frequency band beat frequency with a specific target (determined by the speed r i and rate v i The target is given) associated with the mapping i→n(i), m(i). Therefore, in Figure 3 middle, Reflects that the appropriate association is The following content details how method 100 utilizes Figure 1 The disclosed scans are repeated to find these correct associations.

[0050] During repeated scans, the beat frequency will change due to the change in the distance between scans caused by the target speed, as shown in the following formula:

[0051]

[0052] Here, l = 0, 1, ..., is the scan number. i 、v i Appears as a constant of motion, where r i is the target distance when l=0 scans. In addition, n l 、m l is the beat frequency index, which is tracked to fit the steady rate at which the beat frequency changes between sweeps (this means that if the beat frequency evolution causes the two beat frequencies to cross each other as l advances, the indices will swap).

[0053] Without knowing the mapping i→n(i), m(i), Figure 3 Any of the associations depicted as intersections of beat lines in represents a possible target, and thus the distance and speed values ​​are given by the following formula: gives:

[0054]

[0055] According to formula (4), these formulas can be reused with target distance and speed parameters r i 、v i Expressed as:

[0056]

[0057]

[0058] Obviously, the correct association is where i=j, which means Specifically and most importantly, remain unchanged between scans, whereas for incorrect associations, their values ​​change between scans by r j -r i 、v j -v i Determined by the range and velocity intervals of the incorrectly associated targets.

[0059] Since the scanning room The non-constancy of is a sufficient condition for the association of errors, and the signal processing method used to eliminate false alarms will be based on this property. Figure 1 100, the present invention encompasses utilizing a repeated scanning process Any signal processing method that removes false alarms based on the non-constancy of , as detailed in Equation (6).

[0060] A particularly useful use The non-constancy of is determined by calculating by signal processing the difference between the distance values ​​obtained for the associations in the sequence of scan pairs counted in the positive time direction starting from an arbitrarily chosen time zero and the corresponding associations in the sequence of scan pairs counted in the negative time direction, i.e. forming the quantity:

[0061]

[0062] Further, this step includes: eliminating associations whose distance differences advance from zero at a linear non-zero rate (these eliminated associations indicate all erroneous associations), and can be effectively determined using well-known signal processing techniques (such as linear least squares and linear regression techniques).

[0063] It should be noted that equations (4 to 7) and their use may vary within the scope of the present disclosure. Thus, the present disclosure is not limited to the particular set of equations or particular forms of equations specified herein.

[0064] Figure 4 Schematically, an electronic device 1 is shown, such as a radar device according to some aspects, which is configured to perform the method of any aspect herein. The electronic device 1 includes a control circuit 2 for performing the method 100 herein. The control circuit 2 may include signal processing modules, such as a digital-to-analog conversion module (DAC) 3, an analog-to-digital conversion module (ADC) 4, a fast Fourier transform module 5 (FFT), a mixer 6, an oscillator 7, a filtering unit 8 (e.g., a low-bandpass filter, a high-bandpass filter). Further, the device 1 includes a receiving antenna 11 and a transmitting antenna 12. Each antenna may include an antenna element, an amplifier 13, and any other suitable circuitry of the antenna. The device 1 will also include the required signal processing resources, as an integral part of 2 (as shown in the figure) or as a separate unit external to 2.

[0065] The control circuit / electronics 1 , 2 also comprise / are connected to suitable memory resources, input / output interfaces (not shown) and optionally at least one communication interface.

[0066] Memory resources may include any form of volatile or non-volatile computer-accessible memory, including but not limited to permanent storage, solid-state memory, remotely mounted memory, magnetic media, optical media, random access memory (RAM), read-only memory (ROM), mass storage media (e.g., a hard disk), removable storage media (e.g., a flash drive, a compact disk (CD), or a digital video disk (DVD), and / or any other volatile or non-volatile, non-transitory device-readable and / or computer-executable memory device that stores information, data, and / or instructions that can be used.

[0067] The control circuit 2 can be arranged to execute the instruction set in the memory device to operate the method described herein. The electronic device 1 can also include a processing unit, such as a microprocessor, a digital signal processor (DSP), an application-specific integrated circuit (ASIC), a field programmable gate array (FPGA), or a combination of these, or other similar processing devices arranged to execute the instruction set, which components can be integrated with the control circuit 2 or connected to the control circuit. The computer-readable storage medium can be of non-volatile and / or volatile type and of temporary or non-temporary type; for example, RAM, EEPROM, flash disk, etc.

[0068] The communication interface can be of any suitable type, such as Ethernet, SPI bus, I2C bus, RS232, CAN bus, wireless communication technology, or other communication protocols depending on the application. In addition, the communication interface can be used to transmit results, messages, status reports, etc. to external devices and control units, such as to the user interface / control system of the vehicle.

[0069] The memory resources can be used to store computer programs used for signal processing, transmit waveforms, calibration data, and intermediate results of the signal processing stages.

[0070] The control circuit 2 and / or the electronic device 1 may include, for example, one or more central processing units (CPUs), gate arrays (FPGAs), graphics processing units (GPUs) and / or other processing devices dedicated to performing calculations. The calculations may include, for example, signal processing calculations, such as for determining beat frequency, resolving distance and velocity, and performing the method according to any aspect of the present invention using any suitable form of calculation to eliminate erroneous associations. The memory device may include one or more computer-readable media and may be capable of storing information accessible by the control circuit 2, including instructions / programs, such as instructions for performing the method.

[0071] Figure 5A A system 200 for providing mutual interference suppression is schematically shown, comprising a plurality of similar electronic devices 2, performing a method 100 according to any one of claims 1 to 6, wherein each electronic device 1 utilizes / is configured to utilize / is assigned to transmit a counter-chirp using one of a plurality of transmission channels, wherein adjacent channels of the plurality of transmission channels are time-delayed relative to each other. Each channel is assignable to a single electronic device 1, allowing the device 1 to transmit a scanning pair.

[0072] Figure 5B The arrangement of waveforms for either of the two channels assigned to 1000 electronic devices in the drawing is shown according to the exemplary system 200 showing only the rising chirp. Figure 5BIn this example, the total bandwidth B is 1 GHz, while the bandwidth of any one channel is half that value. Furthermore, up to 1,000 electronic devices can utilize the same frequency band. Furthermore, each electronic device 1 operates in a channel separated from adjacent channels by a time span of 2.5 μs. This disclosure is not limited to 2.5 μs; this is merely an exemplary channel spacing. Therefore, in this example, the total time window is 2.5 ms, which is the repetition rate of the radar signal.

[0073] The voltage leakage between adjacent channels is theoretically valid for the adopted linear chirp signal:

[0074]

[0075] While the illustrative figures given in Figure 5 are suitable for typical automotive radar requirements, different applications place varying demands on the level of suppression required to maintain radar functionality. These requirements depend on factors such as the radar antenna characteristics, the desired surveillance and interference ranges, and the radar cross-section of the objects to be detected. It can be observed that, according to Equation (5), the leakage between adjacent channels is essentially equal to the number of utilized channels divided by the radar's time-bandwidth product, τB. It can be shown that the cumulative interference from more distant channels is negligible compared to the effects of adjacent channels.

[0076] Figure 6 The performance of the method disclosed in this article after its simulation is shown. Figure 6 The purpose of the disclosure is to further describe the disclosure presented herein and its advantages. It should be noted that the performance is based on an embodiment for the purpose of disclosure, however it is not limited to the embodiment and may vary within the disclosure.

[0077] Figure 6 The ability to correlate multiple targets (with accelerations) without any errors is shown in the form of four plots, with random accelerations applied to the targets. Figure 6 The method 100 is disclosed herein as being performed on 20, 30, 50, and 70 objects, respectively, and the accuracy of the velocity and range resolution for these objects is shown.

Claims

1. A method (100) for resolving the distance and velocity of at least one object, the method comprising: - simultaneously transmitting (101) a first electromagnetic waveform and a second electromagnetic waveform, each electromagnetic waveform comprising a frequency modulated chirp having a predetermined sweep time, the first electromagnetic waveform and the second electromagnetic waveform being counter-chirped to form a sweep pair; - independently obtaining (102) a first time domain signal and a second time domain signal formed by reflections of the first electromagnetic waveform and the second electromagnetic waveform of the scanning pair; - determining (103) the beat frequency of the baseband signal of each acquired time domain signal in the scan pair; - determining (104) the speed and distance of the at least one object, wherein if the obtained signal is reflected from a single object, the determining step comprises: - linearly combining (a1) the beat frequencies of the first and second signals obtained of the scanning pair, thereby deriving the speed and distance of a single object; Wherein, if the obtained signal is reflected from multiple objects, the determining step includes: - Linearly combine (b1) the beat frequencies obtained from the signals to derive a number of possible associations, where for P targets the associations are P 2 , P is an integer > 0, and each association indicates a possible target; - transmitting (b2) a further sequence of scan pairs; - Identifying (b3) the correct association based on the sequence.

2. The method (100) according to claim 1, wherein: At a center frequency of 50 GHz to 90 GHz, the predetermined sweep time is 2 milliseconds to 3 milliseconds, preferably 2.25 milliseconds to 2.75 milliseconds, and more preferably 2.5 milliseconds.

3. The method (100) according to any one of claims 1 or 2, wherein: Each first electromagnetic waveform is located in a first frequency channel, and each second electromagnetic waveform is located in a second frequency channel, wherein the first frequency channel and the second frequency channel are adjacent to each other.

4. The method (100) according to any one of the preceding claims, wherein: The identification step (b3) further comprises: - calculating by signal processing the difference between the distance values ​​obtained from an association in the sequence of scan pairs counted in the positive time direction at an arbitrarily chosen time zero and the corresponding association in the sequence of scan pairs counted in the negative time direction; - Eliminate associations whose distance differences advance from zero at a linear non-zero rate. The eliminated associations are all incorrect associations.

5. The method (100) according to claim 4, wherein: Calculations performed through signal processing include: - Obtain the beat frequency tracked by the upper and lower frequency bands The candidate distance values ​​obtained by any pairing of m(l), n(l) = 1, 2, ..., and using the first equation: And, after the first equation, use the second equation: Among them, l = ... -2, -1, 0, 1, 2, ..., is the scan number.

6. The method (100) according to any one of claims 1 to 5, wherein: The chirp is a linear chirp.

7. A computer-readable storage medium storing one or more programs, wherein the one or more programs are configured to be executed by one or more control circuits (2) of an electronic device (1), the one or more programs including instructions for executing the method (100) according to any one of claims 1 to 6.

8. An electronic device (1) having a control circuit (2) configured to perform the method according to any one of claims 1 to 6.

9. A stationary device or a vehicle comprising an electronic device having a control circuit configured to perform the method according to any one of claims 1 to 6.

10. A system (200) comprising a plurality of electronic devices (1) executing the method (100) according to any one of claims 1 to 6, wherein: Each electronic device (1) is configured to transmit a counter-chirp using one of a plurality of transmission channels, wherein adjacent channels of the plurality of transmission channels have a time delay relative to each other.

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