A method for determining spectral information and related devices
By employing different window functions to extract and calculate the phase difference of the frequency-modulated continuous wave lidar signal, the problems of low frequency information resolution and weak signal-to-noise ratio were solved, and more accurate spectral information determination was achieved.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- Filing Date
- 2022-06-06
- Publication Date
- 2026-03-31
AI Technical Summary
In existing technologies, frequency-modulated continuous wave lidar ranging methods have low frequency information resolution and weak signal-to-noise ratio anti-interference capability, resulting in errors in frequency and spectrum information.
M different window functions are used to truncate the target signal, and the spectral information of the target signal is determined by calculating the phase difference of the signal sequence to be processed.
It improves the accuracy and anti-interference capability of spectrum information, reduces spectrum energy leakage, and enhances the resolution of frequency information.
Smart Images
Figure CN115201775B_ABST
Abstract
Description
[Technical Field]
[0001] This invention relates to the field of information processing technology, and in particular to a method and related equipment for determining spectrum information. [Background Technology]
[0002] In radar ranging technology, it is often necessary to calculate the frequency information of the target signal. In frequency-modulated continuous wave lidar ranging, the frequency information of the target signal is often obtained through Fast Fourier Transform (FFT). However, in existing technologies, the traditional FFT method suffers from the picket fence effect, resulting in very low resolution of the obtained frequency information. Furthermore, this method also has weak signal-to-noise ratio and interference resistance, leading to errors in the obtained frequency and spectral information. Therefore, obtaining effective spectral information is a problem that urgently needs to be solved. [Summary of the Invention]
[0003] To address the aforementioned problems, embodiments of the present invention provide a method and related equipment for determining spectrum information, which can obtain more effective spectrum information.
[0004] In a first aspect, embodiments of the present invention provide a method for determining spectrum information, including:
[0005] M different window functions are used to truncate the target signal, resulting in M sets of signal data to be processed, where M ≥ 2;
[0006] The sequence of signals to be processed is determined based on the M sets of signal data to be processed, and the sequence of signals to be processed is a time-domain signal.
[0007] The signal sequence to be processed is delayed by n0 points to obtain a second signal sequence to be processed.
[0008] The phase difference is determined based on the phase of the signal sequence to be processed and the phase of the second signal sequence to be processed;
[0009] The spectral information of the target signal is determined based on the phase difference.
[0010] In this embodiment of the invention, different window functions are used to truncate the target signal to prevent the leakage of spectral information. Then, the sequence of the signal to be processed is determined based on the truncated signal data after different window functions, thereby obtaining the effective spectral information of the target signal.
[0011] In one possible implementation, the M different window functions include at least a Hamming window function and a rectangular window function.
[0012] In one possible implementation, determining the sequence of signals to be processed based on the M sets of signal data to be processed includes:
[0013] The M groups of signal data to be processed are convolved to obtain the signal sequence to be processed.
[0014] In one possible implementation, both the signal sequence to be processed and the second signal sequence to be processed contain (2N-1) data points, where N is a positive integer. Determining the phase difference based on the phase of the signal sequence to be processed and the phase of the second signal sequence to be processed includes:
[0015] The (N-1) data points before the Nth data point in the signal sequence to be processed are added together with the (N-1) data points after the Nth data point, and then frequency domain transformation is performed to obtain a frequency domain signal sequence; wherein the Nth data point is located at the midpoint of the signal data to be processed.
[0016] The (N-1) data points before the Nth data point in the second signal sequence to be processed are added together with the (N-1) data points after the Nth data point, and then frequency domain transformation is performed to obtain the second frequency domain signal sequence; wherein the Nth data point is located at the midpoint of the second signal data to be processed.
[0017] Determine the phase of the frequency domain signal sequence, and determine the phase of the second frequency domain signal sequence;
[0018] The phase difference is determined based on the phase of the frequency domain signal sequence and the phase of the second frequency domain signal sequence.
[0019] In one possible implementation, determining the phase difference based on the phase of the frequency domain signal sequence and the phase of the second frequency domain signal sequence includes:
[0020] The phase compensation value is determined based on the phase of the frequency domain signal sequence and the phase of the second frequency domain signal sequence;
[0021] The phase difference is calculated based on the phase of the frequency domain signal sequence, the phase of the second frequency domain signal sequence, and the phase compensation value.
[0022] In one possible implementation, the (N-1) data points preceding the Nth data point and the (N-1) data points following the Nth data point in the signal sequence to be processed are added together, and then a frequency domain transformation is performed to obtain a frequency domain signal sequence, including:
[0023] Add the (N-1) data points before the Nth data point in the signal sequence to be processed to the (N-1) data points after the Nth data point to obtain the first intermediate data, which includes a real part and an imaginary part;
[0024] The real and imaginary parts of the first intermediate data are linearly calculated with a preset rotation factor to obtain the frequency domain signal sequence.
[0025] In one possible implementation, the method further includes:
[0026] M different window functions are used to extract the target signal multiple times, resulting in multiple sets of signal data to be processed.
[0027] Multiple spectral information is determined based on the multiple M groups of signal data to be processed;
[0028] The optimal spectral information of the target signal is obtained by performing data fitting on the multiple spectral information.
[0029] In a second aspect, embodiments of the present invention provide a spectrum information determination apparatus, comprising:
[0030] Preprocessing unit: used to extract the target signal using M different window functions to obtain M sets of signal data to be processed, where M≥2;
[0031] Processing unit: used to determine the signal sequence to be processed based on the M sets of signal data to be processed, wherein the signal sequence to be processed is a time-domain signal;
[0032] The processing unit is further configured to delay the signal sequence to be processed by n0 points to obtain a second signal sequence to be processed;
[0033] The processing unit is further configured to determine the phase difference based on the phase of the signal sequence to be processed and the phase of the second signal sequence to be processed;
[0034] The processing unit is further configured to determine the spectral information of the target signal based on the phase difference.
[0035] Thirdly, embodiments of the present invention provide an electronic device, comprising:
[0036] At least one processor; and
[0037] At least one memory communicatively connected to the processor, wherein:
[0038] The memory stores program instructions that can be executed by the processor, and the processor can execute the methods described in the first and second aspects by calling the program instructions.
[0039] Fourthly, embodiments of the present invention provide a computer-readable storage medium storing computer instructions that cause the computer to perform the methods described in the first and second aspects.
[0040] It should be understood that the fourth aspect of the present invention is consistent with the technical solutions of the first and second aspects of the present invention, and the beneficial effects achieved by each aspect and the corresponding feasible implementation are similar, and will not be described again. [Attached Image Description]
[0041] To more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.
[0042] Figure 1 A flowchart of a method for determining spectrum information provided in an embodiment of the present invention;
[0043] Figure 2 This is a schematic diagram of the structure of a spectrum information determination device provided in an embodiment of the present invention;
[0044] Figure 3 This is a schematic diagram of the structure of an electronic device provided in an embodiment of the present invention.
Detailed Implementation Methods
[0045] To better understand the technical solutions in this specification, the embodiments of the present invention will be described in detail below with reference to the accompanying drawings.
[0046] It should be understood that the described embodiments are merely some, not all, of the embodiments in this specification. All other embodiments obtained by those skilled in the art based on the embodiments in this specification without inventive effort are within the scope of protection of this invention.
[0047] The terminology used in the embodiments of this invention is for the purpose of describing particular embodiments only and is not intended to be limiting of this specification. The singular forms “a,” “the,” and “the” as used in the embodiments of this invention and the appended claims are also intended to include the plural forms unless the context clearly indicates otherwise.
[0048] In this embodiment of the invention, the target signal is intercepted by M different window functions, which overcomes the shortcomings of weak anti-interference ability and low frequency resolution in the prior art.
[0049] Figure 1 This is a flowchart illustrating a method for determining spectrum information according to an embodiment of the present invention. Figure 1 As shown, the method includes:
[0050] Step 101: The target signal is truncated using M different window functions to obtain M sets of signal data to be processed, where M ≥ 2. In the prior art, digital signal processing mainly relies on Fourier transform. When processing the target signal, it is impossible to measure and operate on an infinitely long signal; instead, a finite time segment is used for analysis. The approach is to truncate a time segment from the target signal and then perform periodic extension processing on the truncated time segment to obtain a virtual infinitely long signal. Then, mathematical processing such as Fourier transform and correlation analysis can be performed on this signal. After the infinitely long signal is truncated, its spectrum is distorted. The energy originally concentrated at f(0) is dispersed into two wider frequency bands. This phenomenon is called spectral energy leakage. To reduce spectral energy leakage, the present invention uses M different window functions to truncate the target signal, which can effectively reduce spectral energy leakage. Optionally, the window function can be a rectangular window function, a triangular window function, a Hanning window function, a Hamming window function, or a Gaussian window function. In some embodiments, the M different window functions include at least a Hamming window function and a rectangular window function. Optionally, the target signal can be a frequency modulated continuous wave (FMCW) signal.
[0051] Step 102: Determine the signal sequence to be processed based on the M groups of signal data to be processed. The signal sequence to be processed is a time-domain signal. Optionally, convolution processing can be performed on the M different groups of signal data to be processed to obtain the signal sequence to be processed.
[0052] In a specific example, an AD acquisition chip can be used to acquire two identical target signals. Then, the first N data points of one target signal are truncated using a Hamming window, and the first N data points of the other target signal are truncated using a rectangular window. Afterward, the truncated two signal data points are convolved to obtain a signal sequence containing (2N-1) data points.
[0053] Step 103: Delay the signal sequence to be processed by n0 points to obtain the second signal sequence to be processed.
[0054] Step 104: Determine the phase difference based on the phase of the first signal sequence and the phase of the second signal sequence. Both the first and second signal sequences contain (2N-1) data points, where N is a positive integer. First, add the (N-1) data points before and after the Nth data point in the first signal sequence and perform a frequency domain transformation to obtain the frequency domain signal sequence. The Nth data point is located at the midpoint of the first signal data. Then, add the (N-1) data points before and after the Nth data point in the second signal sequence and perform a frequency domain transformation to obtain the second frequency domain signal sequence. The Nth data point is also located at the midpoint of the second signal data. Next, determine the phase of both the first and second frequency domain signal sequences. Finally, determine the phase difference based on the phases of both the first and second frequency domain signal sequences.
[0055] Specifically, the phase compensation value can be determined first based on the phase of the frequency domain signal sequence and the phase of the second frequency domain signal sequence. Then, the phase difference is calculated based on the phase of the frequency domain signal sequence, the phase of the second frequency domain signal sequence, and the phase compensation value. In a specific example, the initial phase compensation value can be calculated using the phase of the frequency domain signal sequence, the phase of the second frequency domain signal sequence, and the position of the main spectral line. The phase difference can be calculated using the formula... Received, among which Phase difference The phase corresponding to the second frequency domain signal sequence. The phase corresponding to the frequency domain signal sequence. This is the phase compensation value.
[0056] In some embodiments, during frequency domain transformation, the (N-1) data points before the Nth data point in the signal sequence to be processed are added to the (N-1) data points after the Nth data point to obtain first intermediate data, which includes a real part and an imaginary part. Then, the real and imaginary parts of the first intermediate data are respectively subjected to linear calculations such as addition, subtraction, and multiplication with a preset rotation factor to obtain new real and imaginary parts. That is, the frequency domain signal sequence. The phase is then determined based on the new real and imaginary parts. The processing method for the second signal sequence to be processed is the same and will not be repeated here.
[0057] Step 105: Determine the spectral information of the target signal based on the phase difference. Optionally, the frequency of the target signal can also be calculated using the phase difference. Specifically, this can be done using the formula... To calculate the frequency of the target signal.
[0058] In some embodiments, M different window functions can be used to truncate the target signal multiple times, resulting in multiple sets of signal data to be processed. The above steps are then repeated to determine multiple spectral information based on the multiple sets of signal data to be processed. Finally, data fitting is performed on the multiple spectral information to obtain the optimal spectral information of the target signal.
[0059] Corresponding to the above-described method for determining spectrum information, this embodiment of the invention provides a device for determining spectrum information. For example... Figure 2 As shown, the device includes a preprocessing unit 201 and a processing unit 202.
[0060] Preprocessing unit 201: used to extract the target signal using M different window functions to obtain M sets of signal data to be processed, where M≥2.
[0061] Processing unit 202: used to determine the sequence of signals to be processed based on M sets of signal data to be processed, wherein the sequence of signals to be processed is a time-domain signal.
[0062] The processing unit 202 is also used to delay the signal sequence to be processed by n0 points to obtain a second signal sequence to be processed.
[0063] The processing unit 202 is also configured to determine the phase difference based on the phase of the signal sequence to be processed and the phase of the second signal sequence to be processed.
[0064] The processing unit 202 is also used to determine the spectral information of the target signal based on the phase difference.
[0065] Figure 2 The spectrum information determination device provided in the illustrated embodiment can be used to execute this specification. Figure 1 The implementation principle and technical effects of the method embodiment shown can be further referred to the relevant description in the method embodiment.
[0066] Figure 3 This is a schematic diagram of the structure of an electronic device provided in an embodiment of the present invention, such as... Figure 3 As shown, the aforementioned electronic device may include at least one processor and at least one memory communicatively connected to the processor, wherein the memory stores program instructions executable by the processor, and the processor can execute this specification by calling the program instructions. Figure 1 The illustrated embodiment provides a method for determining spectrum information.
[0067] like Figure 3 As shown, the electronic device is represented in the form of a general-purpose computing device. The components of the electronic device may include, but are not limited to: one or more processors 310, communication interface 320 and memory 330, and a communication bus 340 connecting different system components (including memory 330, communication interface 320 and processor 310).
[0068] Communication bus 340 represents one or more of several bus architectures, including a memory bus or memory controller, a peripheral bus, a graphics acceleration port, a processor, or a local bus using any of the various bus architectures. For example, these architectures include, but are not limited to, Industry Standard Architecture (ISA) buses, Micro Channel Architecture (MAC) buses, Enhanced ISA buses, Video Electronics Standards Association (VESA) local buses, and Peripheral Component Interconnect (PCI) buses.
[0069] Electronic devices typically include a variety of computer-readable media. These media can be any available media that can be accessed by the electronic device, including volatile and non-volatile media, and removable and non-removable media.
[0070] Memory 330 may include computer system readable media in the form of volatile memory, such as random access memory (RAM) and / or cache memory. The electronic device may further include other removable / non-removable, volatile / non-volatile computer system storage media. Memory 330 may include at least one program product having a set (e.g., at least one) of program modules configured to perform the functions of the embodiments described herein.
[0071] A program / utility having a set (at least one) of program modules can be stored in memory 330. Such program modules include—but are not limited to—an operating system, one or more application programs, other program modules, and program data. Each or some combination of these examples may include an implementation of a network environment. The program modules typically perform the functions and / or methods described in the embodiments of this specification.
[0072] Processor 310 executes various functional applications and data processing by running programs stored in memory 330, such as implementing the functions described in this specification. Figure 1 The illustrated embodiment provides a method for determining spectrum information.
[0073] This specification provides a computer-readable storage medium storing computer instructions that cause a computer to execute this specification. Figure 1 The illustrated embodiment provides a method for determining spectrum information.
[0074] The aforementioned computer-readable storage medium may be any combination of one or more computer-readable media. A computer-readable medium may be a computer-readable signal medium or a computer-readable storage medium. A computer-readable storage medium may be, for example,—but not limited to—an electrical, magnetic, optical, electromagnetic, infrared, or semiconductor system, apparatus, or device, or any combination thereof. More specific examples of computer-readable storage media (a non-exhaustive list) include: an electrical connection having one or more wires, a portable computer disk, a hard disk, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM), or flash memory, optical fiber, portable compact disk read-only memory (CD-ROM), optical storage device, magnetic storage device, or any suitable combination thereof. In this document, a computer-readable storage medium may be any tangible medium containing or storing a program that may be used by or in connection with an instruction execution system, apparatus, or device.
[0075] The foregoing has described specific embodiments of this specification. Other embodiments are within the scope of the appended claims. In some cases, the actions or steps recited in the claims may be performed in a different order than that shown in the embodiments and may still achieve the desired result. Furthermore, the processes depicted in the drawings do not necessarily require the specific or sequential order shown to achieve the desired result. In some embodiments, multitasking and parallel processing are possible or may be advantageous.
[0076] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of this specification. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.
[0077] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this specification, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.
[0078] Any process or method described in the flowchart or otherwise herein can be understood as representing a module, segment, or portion of code comprising one or more executable instructions for implementing custom logic functions or processes, and the scope of the preferred embodiments of this specification includes additional implementations in which functions may be performed not in the order shown or discussed, including substantially simultaneously or in reverse order depending on the functions involved, as will be understood by those skilled in the art to which the embodiments of this specification pertain.
[0079] Depending on the context, the word "if" as used here can be interpreted as "when," "when," "in response to determination," or "in response to detection." Similarly, depending on the context, the phrase "if determination" or "if detection (of the stated condition or event)" can be interpreted as "when determination," "in response to determination," "when detection (of the stated condition or event)," or "in response to detection (of the stated condition or event)."
[0080] It should be noted that the devices involved in the embodiments of this specification may include, but are not limited to, personal computers (hereinafter referred to as PCs), personal digital assistants (hereinafter referred to as PDAs), wireless handheld devices, tablet computers, mobile phones, MP3 displays, MP4 displays, etc.
[0081] In the several embodiments provided in this specification, it should be understood that the disclosed systems, apparatuses, and methods can be implemented in other ways. For example, the apparatus embodiments described above are merely illustrative; for instance, the division of units is only a logical functional division, and in actual implementation, there may be other division methods. For example, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Furthermore, the coupling or direct coupling or communication connection shown or discussed may be through some interfaces; the indirect coupling or communication connection between apparatuses or units may be electrical, mechanical, or other forms.
[0082] Furthermore, the functional units in the various embodiments of this specification can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit. The integrated unit can be implemented in hardware or in a combination of hardware and software functional units.
[0083] The integrated units implemented as software functional units described above can be stored in a computer-readable storage medium. These software functional units, stored in a storage medium, include several instructions to cause a computer device (which may be a personal computer, a connector, or a network device, etc.) or a processor to execute some steps of the methods described in the various embodiments of this specification. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.
[0084] The above description is merely a preferred embodiment of this specification and is not intended to limit this specification. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this specification should be included within the scope of protection of this specification.
Claims
1. A method of determining spectral information, characterized by, include: M different window functions are used to truncate the target signal, resulting in M sets of signal data to be processed, where M ≥ 2; The sequence of signals to be processed is determined based on the M sets of signal data to be processed, and the sequence of signals to be processed is a time-domain signal. The signal sequence to be processed is delayed by n0 points to obtain a second signal sequence to be processed. The phase difference is determined based on the phase of the signal sequence to be processed and the phase of the second signal sequence to be processed; The spectral information of the target signal is determined based on the phase difference; Determine the sequence of signals to be processed based on the M sets of signal data to be processed, including: The M groups of signal data to be processed are convolved to obtain the signal sequence to be processed; Both the signal sequence to be processed and the second signal sequence to be processed contain (2N-1) data points, where N is a positive integer. The phase difference is determined based on the phase of the signal sequence to be processed and the phase of the second signal sequence to be processed, including: The (N-1) data points before the Nth data point in the signal sequence to be processed are added together with the (N-1) data points after the Nth data point, and then frequency domain transformation is performed to obtain a frequency domain signal sequence; wherein the Nth data point is located at the midpoint of the signal data to be processed. The (N-1) data points before the Nth data point in the second signal sequence to be processed are added together with the (N-1) data points after the Nth data point, and then frequency domain transformation is performed to obtain the second frequency domain signal sequence; wherein the Nth data point is located at the midpoint of the second signal data to be processed. Determine the phase of the frequency domain signal sequence, and determine the phase of the second frequency domain signal sequence; The phase difference is determined based on the phase of the frequency domain signal sequence and the phase of the second frequency domain signal sequence.
2. The method of claim 1, wherein, The M different window functions include at least the Hamming window function and the rectangular window function.
3. The method of claim 1, wherein, Determining the phase difference based on the phase of the frequency domain signal sequence and the phase of the second frequency domain signal sequence includes: The phase compensation value is determined based on the phase of the frequency domain signal sequence and the phase of the second frequency domain signal sequence; The phase difference is calculated based on the phase of the frequency domain signal sequence, the phase of the second frequency domain signal sequence, and the phase compensation value.
4. The method of claim 1, wherein, The (N-1) data points preceding the Nth data point and the (N-1) data points following the Nth data point in the signal sequence to be processed are added together, and then a frequency domain transformation is performed to obtain a frequency domain signal sequence, including: Add the (N-1) data points before the Nth data point in the signal sequence to be processed to the (N-1) data points after the Nth data point to obtain the first intermediate data, which includes a real part and an imaginary part; The real and imaginary parts of the first intermediate data are linearly calculated with a preset rotation factor to obtain the frequency domain signal sequence.
5. The method of claim 1, wherein, The method further includes: M different window functions are used to extract the target signal multiple times, resulting in multiple sets of signal data to be processed. Multiple spectral information is determined based on the multiple M groups of signal data to be processed; The optimal spectral information of the target signal is obtained by performing data fitting on the multiple spectral information.
6. A spectrum information determining apparatus characterized by comprising: include: The preprocessing unit is configured to intercept the target signal by using M different window functions to obtain M groups of to-be-processed signal data, where M≥2. The processing unit is configured to determine a to-be-processed signal sequence according to the M groups of to-be-processed signal data, the to-be-processed signal sequence being a time-domain signal. The processing unit is further configured to delay the to-be-processed signal sequence by n0 points to obtain a second to-be-processed signal sequence. The processing unit is further configured to determine a phase difference according to a phase of the to-be-processed signal sequence and a phase of the second to-be-processed signal sequence. The processing unit is further configured to determine spectral information of the target signal according to the phase difference. The processing unit is specifically configured to: perform convolution processing on the M groups of to-be-processed signal data to obtain the to-be-processed signal sequence. The to-be-processed signal sequence and the second to-be-processed signal sequence each contain (2N-1) data, where N is a positive integer, and the processing unit is specifically configured to: add (N-1) data before the Nth data in the to-be-processed signal sequence to (N-1) data after the Nth data, and then perform frequency domain transformation to obtain a frequency domain signal sequence; where the Nth data is located at a midpoint position in the to-be-processed signal data. add (N-1) data before the Nth data in the second to-be-processed signal sequence to (N-1) data after the Nth data, and then perform frequency domain transformation to obtain a second frequency domain signal sequence; where the Nth data is located at a midpoint position in the second to-be-processed signal data. determine a phase of the frequency domain signal sequence and a phase of the second frequency domain signal sequence. determine the phase difference according to the phase of the frequency domain signal sequence and the phase of the second frequency domain signal sequence.
7. An electronic device, comprising: The apparatus includes: at least one processor; and at least one memory communicatively connected to the processor, wherein: the memory stores program instructions executable by the processor, and the processor invoking the program instructions can execute the method of any one of claims 1 to 5.
8. A computer-readable storage medium, characterized in that, The computer readable storage medium stores computer instructions, and the computer instructions cause the computer to execute the method of any one of claims 1 to 5.