Carrier signal processing method and device based on OFDM (Orthogonal Frequency Division Multiplexing) system and electronic equipment

Abstract

The invention discloses a carrier signal processing method and device based on an OFDM (Orthogonal Frequency Division Multiplexing) system and electronic equipment, and belongs to the technical field of communication. The carrier signal processing method comprises the following steps: acquiring signal energy of a current sampling point in a current signal segment in a digital signal; performing amplitude suppression processing on the signal energy of the current sampling point based on a comparison result of the signal energy of the current sampling point and reference energy; the reference energy is determined based on average signal energy of historical sampling points respectively corresponding to a plurality of historical signal segments in the digital signal, and the number of the sampling points of each signal segment in the digital signal is the same; and executing carrier synchronization processing based on the signal energy of the current sampling point after the amplitude suppression processing. According to the invention, filtering of impulse or impulse noise sampling points is realized, the accuracy of signal synchronization is improved, and the reliability of an OFDM system is improved.

Description

Technical Field

[0001] This application belongs to the field of communication technologies, and particularly relates to a method, apparatus, and electronic device for processing carrier signals in an OFDM system. Background Art

[0002] In an OFDM (Orthogonal Frequency Division Multiplexing) system, the analog front-end subsystem usually includes an Automatic Gain Control (AGC) module, an analog filter, and an Analog-to-digital Converter (ADC). The core function of the AGC is to avoid signal saturation or too small an amplitude during ADC quantization by dynamically adjusting the gain, ensuring that the baseband demodulation module obtains a digital signal with a stable amplitude.

[0003] However, the gain adjustment of the AGC has a time lag, that is, when there is a sudden change in the received signal energy, it takes a period of time to adjust to the appropriate level. At high signal-to-noise ratios, this time lag of the AGC can cause a large energy output for a period of time when the signal first arrives, or a so-called impulse, resulting in signal saturation or causing a deviation during the synchronization process, affecting the synchronization accuracy. Summary of the Invention

[0004] This application aims to solve at least one of the technical problems existing in the related art. For this purpose, this application provides a method, apparatus, and electronic device for processing carrier signals in an OFDM system, which can filter out impulse or pulse noise sampling points, thereby improving the accuracy of signal synchronization and further improving the reliability of the OFDM system.

[0005] In a first aspect, this application provides a method for processing carrier signals in an OFDM system, the method comprising: Obtaining the signal energy of the current sampling point within the current signal segment in the digital signal; Based on the comparison result between the signal energy of the current sampling point and the reference energy, performing amplitude suppression processing on the signal energy of the current sampling point; the reference energy is determined based on the average signal energy of the historical sampling points corresponding to multiple historical signal segments in the digital signal, and the number of sampling points in each signal segment of the digital signal is the same; Performing carrier synchronization processing based on the signal energy of the current sampling point after amplitude suppression processing.

[0006] According to the carrier signal processing method of this application, the performing amplitude suppression processing on the signal energy of the current sampling point based on the comparison result between the signal energy of the current sampling point and the reference energy includes: If the signal energy of the current sampling point is greater than the reference energy, the signal energy of the current sampling point is set to zero; if the signal energy of the current sampling point is less than or equal to the reference energy, the signal energy of the current sampling point remains unchanged.

[0007] According to the carrier signal processing method of the present application, the reference energy is determined based on the minimum value of the average signal energies of the historical sampling points corresponding to the multiple historical signal segments.

[0008] According to the carrier signal processing method of the present application, the number of sampling points in each signal segment of the digital signal is determined based on the number of synchronization preamble symbols included in the preamble signal corresponding to the digital signal and the number of sampling points included in the synchronization preamble symbols.

[0009] According to the carrier signal processing method of the present application, the number of sampling points in each signal segment of the digital signal is greater than or equal to the number of sampling points included in the synchronization preamble symbols; the total number of sampling points of the multiple historical signal segments is less than the product value of the number of synchronization preamble symbols and the number of sampling points included in the synchronization preamble symbols.

[0010] According to the carrier signal processing method of the present application, obtaining the signal energy of the current sampling point in the current signal segment of the digital signal includes: Obtaining the initial signal energy of the current sampling point in the initial digital signal; Multiplying the initial signal energy of the current sampling point by the current gain to obtain the signal energy of the current sampling point; the current gain is updated based on the signal energy of the previous sampling point before the current sampling point.

[0011] According to the carrier signal processing method of the present application, the initial digital signal is the output signal of a digital filter.

[0012] According to the carrier signal processing method of the present application, performing carrier synchronization processing based on the signal energy of the current sampling point after amplitude suppression processing includes: Based on the comparison result between the signal energy of the current sampling point and a preset saturation threshold, performing clipping processing on the signal energy of the current sampling point after amplitude suppression processing; the saturation threshold is less than the reference energy; Performing carrier synchronization processing based on the signal energy of the current sampling point after clipping processing.

[0013] In a second aspect, the present application provides a carrier signal processing device based on an OFDM system, and the device includes: A sampling point acquisition module, configured to acquire the signal energy of the current sampling point in the current signal segment of the digital signal; A sampling point processing module for performing amplitude suppression processing on the signal energy of the current sampling point based on the comparison result between the signal energy of the current sampling point and the reference energy; the reference energy is determined based on the average signal energy of historical sampling points corresponding to multiple historical signal segments in the digital signal, and the number of sampling points in each signal segment of the digital signal is the same; A synchronization processing module for performing carrier synchronization processing based on the signal energy of the current sampling point after amplitude suppression processing.

[0014] In a third aspect, the present application provides an electronic device, including a memory, a processor, and a computer program stored on the memory and executable on the processor. When the processor executes the computer program, it implements the carrier signal processing method based on the OFDM system as described in the first aspect above.

[0015] In a fourth aspect, the present application provides a non-transitory computer-readable storage medium, on which a computer program is stored. When the computer program is executed by a processor, it implements the carrier signal processing method based on the OFDM system as described in the first aspect above.

[0016] In a fifth aspect, the present application provides a chip, which includes a processor and a communication interface. The communication interface is coupled to the processor, and the processor is used to run programs or instructions to implement the carrier signal processing method based on the OFDM system as described in the first aspect.

[0017] In a sixth aspect, the present application provides a computer program product, including a computer program. When the computer program is executed by a processor, it implements the carrier signal processing method based on the OFDM system as described in the first aspect above.

[0018] One or more of the above technical solutions in the embodiments of the present application have at least one of the following technical effects: Further, by automatically tracking the signal energy of each newly arrived sampling point, detecting impulse or pulse noise sampling points according to the comparison result between the signal energy and the reference energy, and filtering the impulse or pulse noise sampling points through amplitude suppression processing, the accuracy of signal synchronization is improved, and thus the reliability of the OFDM system is improved; Furthermore, by calculating the reference energy through the average signal energy of historical sampling points corresponding to multiple historical signal segments, on the basis of increasing the tracking sensitivity, it is ensured that the calculated reference energy is more likely to represent the reasonable energy range of the real signal, thereby further improving the accuracy of signal synchronization.

[0019] The additional aspects and advantages of the present application will be partially given in the following description, partially become obvious from the following description, or be understood through the practice of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] The above and / or additional aspects and advantages of the present application will become apparent and be readily understood from the description of the embodiments in conjunction with the following drawings, in which: Figure 1 is an architecture diagram of a simulation front-end subsystem provided by the related art; Figure 2 is a comparison diagram of received signal headers with and without impulses provided by the related art; Figure 3 is one of the schematic flowcharts of a carrier signal processing method based on an OFDM system provided by an embodiment of the present application; Figure 4a is one of the schematic diagrams of a reference energy provided by an embodiment of the present application; Figure 4b is a second schematic diagram of a reference energy provided by an embodiment of the present application; Figure 4c is a third schematic diagram of a reference energy provided by an embodiment of the present application; Figure 5 is a data flow diagram of a feedback digital gain control provided by an embodiment of the present application; Figure 6 is an architecture diagram of an OFDM system provided by an embodiment of the present application; Figure 7 is a second schematic flowchart of a carrier signal processing method based on an OFDM system provided by an embodiment of the present application; Figure 8 is a third schematic flowchart of a carrier signal processing method based on an OFDM system provided by an embodiment of the present application; Figure 9 is a structural diagram of a carrier signal processing device based on an OFDM system provided by an embodiment of the present application; Figure 10 is a structural schematic diagram of an electronic device provided by an embodiment of the present application. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0021] Next, the technical solutions in the embodiments of the present application will be clearly described in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are some, but not all, of the embodiments of the present application. All other embodiments obtained by those of ordinary skill in the art based on the embodiments in the present application fall within the scope of protection of the present application.

[0022] The terms "first", "second", etc. in the specification and claims of the present application are used to distinguish similar objects, and are not used to describe a specific order or sequence. It should be understood that the data used in this way can be interchangeable under appropriate circumstances, so that the embodiments of the present application can be implemented in an order other than those illustrated or described here, and the objects distinguished by "first", "second", etc. are generally of one type, and the number of objects is not limited. For example, the first object can be one or more. In addition, "and / or" in the specification and claims represents at least one of the connected objects, and the character " / " generally indicates that the objects associated with each other are in an "or" relationship.

[0023] In combination with the accompanying drawings, the carrier signal processing method based on the OFDM system, the carrier signal processing device based on the OFDM system, the electronic device and the readable storage medium provided in the embodiments of the present application are described in detail through specific embodiments and their application scenarios.

[0024] The carrier signal processing method based on the OFDM system can be applied to a terminal, and can be specifically executed by hardware or software in the terminal.

[0025] The carrier signal processing method based on the OFDM system provided in the embodiment of the present application may be an electronic device or a functional module or functional entity in the electronic device that can implement the carrier signal processing method. The electronic devices mentioned in the embodiment of the present application include but are not limited to mobile phones, tablet computers, computers, cameras, and wearable devices. The carrier signal processing method based on the OFDM system provided in the embodiment of the present application is described below using the electronic device as an example of the execution subject.

[0026] Figure 1 This is the architecture diagram of the analog front-end subsystem provided by the relevant technology, such as Figure 1 As shown in the figure, in digital communication systems, in order to avoid saturation or too small of the signal after analog-to-digital conversion and facilitate the hardware baseband to perform demodulation and other processing, it is necessary to amplify or reduce the received signal of uncertain energy to approximately the same energy level in advance at the receiving end, that is, automatic gain control. This step is usually completed in the analog front end (Analog Front-End, AFE). The general process is to count the energy of the digital signal at the receiving end after ADC conversion and compare it with the given target reference, and adjust the target gain according to the difference, and feed the gain back to the AFE before the ADC in the form of a digital signal for gain application.

[0027] Figure 2 This is a comparison diagram of the received signal frame header with impulse and without impulse provided by the related technology, such as Figure 2As shown, at high signal-to-noise ratios, there is a significant mutation in the energy input to the receiver before and after the actual arrival of the valid signal. However, the automatic gain control can only reduce the large gain originally applied before the arrival of the valid signal to the small gain after the arrival of the valid signal after a period of time when the valid signal arrives. During this process, the automatic gain control will cause a large energy output for a period of time, or what is called an impulse. The impulse caused by the automatic gain control generally appears when the valid signal just arrives, that is, the frame header. In a digital communication system, the frame header is often a repeating sequence used for synchronization. While the impulse saturates, it still retains some characteristics of the repeating sequence, so it may affect the accuracy of subsequent synchronization (even when taking saturation). At high signal-to-noise ratios, since there is an obvious difference between noise and the valid signal, before the valid signal arrives, in order to maintain the energy of the received signal within a certain range, the gain will remain at a large gain. When the valid signal arrives, the gain cannot be adjusted quickly in time (that is, the average energy within a certain period of time will not increase immediately, but gradually increases). At this time, the gain will change from a large gain to a medium gain until it becomes a small gain (the small gain is the actual target gain). This lagged adjustment will lead to subsequent synchronization accuracy problems. For example, a large gain or medium gain in the frame header part of the synchronization symbol will cause signal saturation (such as when exceeding the dynamic range processed by the ADC, signal saturation will flatten the peak of the signal, resulting in waveform distortion), thus affecting the synchronization accuracy; or if the energy of the sampling points in the synchronization symbol is inconsistent, there will be a deviation during the synchronization process, resulting in poor synchronization accuracy.

[0028] Regarding the above problems, considering that the communication protocol generally leaves redundancy in the number of repetitions of the repeating sequence during design, that is, only a part of the repeating sequence is needed to complete synchronization. Therefore, the embodiments of the present application can avoid the impact of automatic gain control on synchronization by detecting and filtering this impulse.

[0029] Figure 3 is one of the flow diagrams of the carrier signal processing method based on the OFDM system provided by the embodiments of the present application. As Figure 3 shown, the carrier signal processing method includes: step 110, step 120, and step 130.

[0030] Step 110: Obtain the signal energy of the current sampling point in the current signal segment of the digital signal.

[0031] In actual implementation, the signal after analog-to-digital conversion can be directly used as the digital signal, or the filtered signal obtained through digital filtering processing can be used as the digital signal, or the signal obtained through other processing such as digital gain control can be used as the digital signal. The embodiments of the present application do not make specific limitations on this.

[0032] Step 120: Perform amplitude suppression processing on the signal energy of the current sampling point based on the comparison result between the signal energy of the current sampling point and the reference energy; the reference energy is determined based on the average signal energy of the historical sampling points corresponding to multiple historical signal segments in the digital signal, and the number of sampling points in each signal segment in the digital signal is the same.

[0033] In actual implementation, a sampling point sequence composed of a preset number of sampling points in the digital signal can be used as a signal segment in sequence. The signal energy of each sampling point within each signal segment is statistically calculated and averaged to obtain the average signal energy. Multiple historical signal segments correspond to the current signal segment. The signal segments before the current signal segment are historical signal segments, and the sampling points within the historical signal segments are historical sampling points.

[0034] The reference energy is intended to represent the reasonable energy range of normal signals. Specifically, the reference energy can be determined according to the minimum value of the average signal energy corresponding to multiple historical signal segments, or can be determined according to the average value of the two smaller values of the average signal energy corresponding to multiple historical signal segments. The specific determination method can be directly used as the reference energy, or a simple mathematical operation such as adding a constant or multiplying by a coefficient can be performed on this basis, and the value obtained by the operation is used as the reference energy. The embodiments of the present application do not make specific limitations on this. The amplitude suppression processing can specifically be to set the signal energy of the current sampling point to zero, or to suppress the signal energy of the current sampling point to a smaller threshold, for example, 0.1. The embodiments of the present application also do not make specific limitations on this.

[0035] Step 130: Perform carrier synchronization processing based on the signal energy of the current sampling point after amplitude suppression processing.

[0036] In actual implementation, the reference energy can be determined using the average signal energy corresponding to multiple historical signal segments, and as new sampling points are continuously accumulated to form new signal segments, the reference energy is continuously updated. When the new sampling points, that is, the current sampling points within the current signal segment, arrive in sequence, the reference energy determined using the average signal energy corresponding to multiple historical signal segments before the current signal segment is used to judge the signal energy of the current sampling point. If it is greater than the reference energy, it is considered that the current sampling point belongs to an impulse signal or pulse noise, and amplitude suppression processing is performed on the signal energy of the current sampling point to achieve the filtering of impulse signals or pulse noise. If the signal energy of the current sampling point is less than or equal to the reference energy, the signal energy of the current sampling point can be kept unchanged. On this basis, carrier synchronization processing can be performed, and finally a relatively accurate frame synchronization position can be obtained.

[0037] Taking the number of sampling points in each signal segment as 256 and the number of historical signal segments used to determine the reference energy as 5 as an example, the 1st to 256th current sampling points in the current signal segment can be obtained in sequence. When judging the signal energy for each current sampling point, the same reference energy can be used, and this reference energy is determined according to the average signal energy of the historical sampling points corresponding to the previous 5 historical signal segments. After these 256 current sampling points in the current signal segment are obtained, the reference energy can be updated according to the average signal energy corresponding to the current signal segment and the 4 historical signal segments before the current signal segment, and used for judging the signal energy of the sampling points in the next signal segment. When the sampling points in the next signal segment arrive, the next signal segment can be used as the current signal segment to execute steps 110 to 130.

[0038] It can be understood that the analog signal processing part usually includes automatic gain control. In the case of high signal-to-noise ratio, automatic gain control (such as in the case of large gain) will cause impulses at the position of the effective signal frame header, and the impulses will result in a large signal energy at the frame header position. In power line carrier communication, the synchronization of signals is based on the autocorrelation or cross-correlation calculation of the energy of the sampling points in the synchronization symbols in the received signal, and then the synchronization position is determined according to the position of the autocorrelation peak or cross-correlation peak. Although the impulses of the effective signal will cause waveform distortion or inconsistent energy of the sampling points in the received synchronization symbols, a part of the characteristics of the repetitive sequence are still retained, and autocorrelation peaks or cross-correlation peaks can still be generated. However, the impulses will cause deviations in the peak positions, resulting in synchronization accuracy deviation and affecting the subsequent demodulation effect. To solve this problem, in the embodiments of the present application, by comparing the signal energy of the sampling points with the reference energy and performing amplitude suppression processing on the sampling points greater than the reference energy, impulse sampling points can be filtered out, avoiding the generation of autocorrelation peaks or cross-correlation peaks by the synchronization symbols containing impulse sampling points, and thus avoiding the influence of impulse sampling points on the synchronization accuracy. In addition, even without the automatic gain control part or in the case of low signal-to-noise ratio, the embodiments of the present application can also filter out impulse noise and similarly avoid the influence on the synchronization accuracy. It should be noted that according to the communication protocol, the received signal will include multiple synchronization symbols, and by using the synchronization symbols without impulse sampling points for synchronization, the synchronization accuracy can be improved.

[0039] It should be noted that in order to make the reference energy used for judgment, i.e., the impulse threshold, represent the reasonable energy range of the normal signal as much as possible, considering that if the average signal energy corresponding to a historical signal segment, i.e., the historical short-time average energy, is used, if the influence of the pulse or impulse itself on the statistical historical short-time average energy is to be excluded as much as possible, the statistical window length needs to be set larger, but a larger window length may cause the threshold to change slowly, so that under high signal-to-noise ratio, too many normal signal sampling points will be filtered out as useless impulses after the frame arrives (the sensitivity of threshold tracking is poor). Using multiple historical short-time average energies as the basis for judgment of the reference energy, the statistical window length, i.e., the number of sampling points in each signal segment, will not be too long. Its advantage is that a small number of statistical sampling points can be used for statistics, which can not only increase the sensitivity of threshold tracking, but also better ensure that the threshold represents the reasonable energy range of the normal signal (because it can be considered that at least one historical short-time average energy does not count the energy of the impulse), thereby further improving the accuracy of signal synchronization.

[0040] According to the carrier signal processing method provided in the embodiment of the present application, the signal energy of each newly arrived sampling point is automatically tracked, the impulse or pulse noise sampling point is detected according to the comparison result of the signal energy and the reference energy, and the impulse or pulse noise sampling point is filtered out through amplitude suppression processing, thereby improving the accuracy of signal synchronization and further improving the reliability of the OFDM system. In addition, the reference energy is calculated by the average signal energy of the historical sampling points corresponding to multiple historical signal segments, and on the basis of increasing the tracking sensitivity, it is ensured that the calculated reference energy is more likely to represent the reasonable energy range of the real signal, thereby further improving the accuracy of signal synchronization.

[0041] In some embodiments, step 120 may include: If the signal energy of the current sampling point is greater than the reference energy, the signal energy of the current sampling point is set to zero; if the signal energy of the current sampling point is less than or equal to the reference energy, the signal energy of the current sampling point is kept unchanged.

[0042] It can be understood that the sampling points with energy greater than the reference energy are usually impulse or pulse noise and do not carry effective information of the signal. In order to completely eliminate the influence of impulse or pulse noise on signal synchronization, the embodiment of the present application compares the signal energy of the current sampling point with the reference energy. If the signal energy of the current sampling point is greater than the reference energy, the signal energy of the sampling point is set to zero; if the signal energy of the current sampling point is less than or equal to the reference energy, the signal energy of the current sampling point is kept unchanged.

[0043] In some embodiments, the reference energy may be determined based on a minimum value of average signal energies of historical sampling points corresponding to a plurality of historical signal segments.

[0044] It can be understood that, considering that it is usually guaranteed that at least one historical short-time average energy does not count the energy of the impulse, in order to obtain a better benchmark energy and further improve the accuracy of signal synchronization, the benchmark energy in the embodiment of the present application can be determined based on the minimum value of the average signal energy of the historical sampling points corresponding to multiple historical signal segments.

[0045] In actual implementation, the specific determination method can be to directly use the minimum value as the benchmark energy, or to perform simple mathematical operations on this basis, such as superimposing a constant or multiplying by a coefficient, and use the value obtained by the operation as the benchmark energy. It can be specifically set according to the signal type or actual communication situation, and the embodiment of the present application does not make specific limitations on this.

[0046] It can be understood that the reference energy is positively correlated with the minimum value of the average signal energies corresponding to the multiple historical signal segments, that is, the larger the minimum value of the average signal energies corresponding to the multiple historical signal segments, the larger the reference energy will be. Figure 4a , Figure 4b and Figure 4c are schematic diagrams of the reference energy provided in the embodiments of the present application, taking the number of historical signal segments used to determine the reference energy as 3 as an example, Figure 4a As shown, the minimum value of the average signal energy corresponding to n1, n2 and n3 respectively determines the reference energy as A1, such as Figure 4b As shown, the reference energy determined by the minimum value of the average signal energies corresponding to n1, n2 and n3 is also A1, as shown in Figure 4c As shown, the reference energy determined by the minimum value of the average signal energies corresponding to n1, n2 and n3 is A2, and A2 is greater than A1.

[0047] In some embodiments, the number of sampling points of each signal segment in the digital signal may be determined based on the number of synchronization preamble symbols included in the preamble signal corresponding to the digital signal and the number of sampling points included in the synchronization preamble symbol.

[0048] It is understandable that in the power carrier communication protocol, the impulse caused by the automatic gain control generally appears in the frame header part, which includes a preamble signal for synchronization, and the preamble signal includes multiple synchronization preamble symbols (Synchronization Preamble, SYNCP), and the SYNCP symbol is the basic unit of the synchronization process. In order to further improve the accuracy of signal synchronization, the embodiment of the present application determines the number of sampling points of the signal segment through the SYNCP symbol included in the preamble signal and the number of sampling points included in the SYNCP symbol to obtain a better reference energy. Here, the preamble signal is a sampling point sequence for synchronization included in the frame header part of the digital signal.

[0049] It should be noted that the number of sampling points included in the synchronization preamble symbol must be an integer, while the number of synchronization preamble symbols included in the preamble signal can be an integer or a decimal. For example, in the power line carrier communication protocol, the header part includes a preamble signal for synchronization, and the preamble signal includes 10.5 SYNCP symbols for synchronization. The number of sampling points in each signal segment can be directly calculated according to the number of synchronization preamble symbols included in the preamble signal and the number of sampling points included in the synchronization preamble symbol, or a certain range of numbers can be determined according to the number of synchronization preamble symbols included in the preamble signal and the number of sampling points included in the synchronization preamble symbol, and then a selection can be made from them. The embodiments of the present application do not make specific limitations in this regard.

[0050] In some embodiments, the number of sampling points in each signal segment of the digital signal can be greater than or equal to the number of sampling points included in the synchronization preamble symbol; the total number of sampling points of multiple historical signal segments can be less than the product value of the number of synchronization preamble symbols and the number of sampling points included in the synchronization preamble symbol.

[0051] For example, if the preamble signal includes 10.5 SYNCP symbols and each SYNCP symbol includes 1024 sampling points, then the number of sampling points in each signal segment can be greater than or equal to the number of sampling points included in 1 SYNCP symbol, but less than (10.5×1024 / n), where n is the number of historical signal segments used to determine the reference energy, that is, the total number of sampling points of multiple historical signal segments is less than 10.5×1024.

[0052] Here, the number n of historical signal segments used to determine the reference energy can be an integer not less than 3 and not greater than the number of synchronization preamble symbols included in the preamble signal. The specific values of the number of sampling points in each signal segment and the number of historical signal segments can be set according to the actual communication situation. The embodiments of the present application do not make specific limitations in this regard.

[0053] According to the carrier signal processing method provided by the embodiment of the present application, by controlling the number of sampling points of the signal segment to be greater than or equal to the number of sampling points included in the synchronization preamble symbol, on the one hand, the frequent update of the reference energy due to the insufficient number of sampling points in the signal segment is avoided, and on the other hand, the problem that some impulse signals cannot be effectively removed due to the window being too small is avoided (for example, if the total number of sampling points of the historical signal segment is less than the impulse signal range, the subsequent impulse points cannot be effectively set to zero); the total number of sampling points of multiple historical signal segments, that is, the total number of sampling points used to determine the reference energy, is controlled within the range of the preamble signal, so that the impulse part and the impulse-free part in the preamble signal can be effectively distinguished, so that the reference energy can be updated in time, and then the determined reference energy can be further guaranteed to represent the reasonable energy range of the normal signal. In the embodiment of the present application, the range and number of the signal segment are adjusted based on the number and number of sampling points of the synchronization symbol, so that the reference energy can be updated in time to ensure that the impulse point is effectively set to zero. It should be noted that the impulse signal range is related to the actual signal-to-noise ratio, the gain coefficient, and the gain adjustment response time. The specific number and range of historical signal segments should be set based on the actual impulse signal range and the leading signal range.

[0054] In some embodiments, step 110 may include: Obtaining the initial signal energy of the current sampling point in the initial digital signal; The initial signal energy of the current sampling point is multiplied by the current gain to obtain the signal energy of the current sampling point; the current gain is updated based on the signal energy of the previous sampling point before the current sampling point.

[0055] It should be noted that in the related technology, automatic gain control is usually completed in the analog front end (AFE), but considering the hardware cost and design difficulty, it is difficult for the analog circuits (filters, amplifiers, etc.) generally used to apply gain to achieve a wide range of continuously variable gain control; in addition, the fixed energy signal that the baseband hopes to obtain is the in-band signal after filtering, but under low signal-to-noise ratio, due to the performance limitations of the analog filter, the signal reaching the baseband may be saturated or too small. The analog filter cannot completely remove out-of-band noise. If the comparison point of the analog gain control is placed before the digital filter (with noise), the energy after filtering (after noise removal) will be greatly reduced and cannot meet the requirements; if the comparison point is placed after the digital filter (noise-free), it is easy to saturate before filtering and cause signal distortion. These problems gave rise to the practice of adding digital gain control.

[0056] In this regard, based on the analog gain control, the embodiment of the present application adds digital gain control to obtain the signal energy of the current sampling point. Different from the analog gain control, the digital gain control specifically applies a gain to the filtered signal of the current sampling point through a digital multiplier. Therefore, its resolution and adjustable range are only affected by the signal bit width, and it is easy to obtain better performance with almost no increase in cost, improving the control efficiency while improving the adjustment accuracy. It can be understood that the analog gain control is a coarse gain adjustment, and the digital gain control is a fine gain adjustment, and the effective control of the signal energy is achieved through the adjustment of both.

[0057] When the initial signal energy of the current sampling point in the initial digital signal is input to the digital gain control, the digital gain controller multiplies the initial signal energy of the current sampling point by the current gain to obtain the signal energy of the current sampling point, and then updates the next gain according to the signal energy of the current sampling point. When the initial signal energy of the next sampling point arrives, the next gain can participate in the calculation of the signal energy of the next sampling point, and so on, to realize the calculation of the signal energy and the real-time update of the gain.

[0058] Here, the digital gain control can adopt first-order digital gain control or multi-stage digital gain control, and the embodiment of the present application does not make specific limitations in this regard.

[0059] In some embodiments, the digital gain control can update the current gain corresponding to the current sampling point based on the difference between the gain average energy and the preset reference energy; the gain average energy is obtained by iteratively updating the average signal energy of the historical sampling points within the preset time window based on the signal energy of the previous sampling point before the current sampling point.

[0060] Taking the first-order digital gain control as an example, as Figure 5 The data flow diagram of the feedback digital gain control provided by the embodiment of the present application is given, which processes each sampling point of the digital signal. The main process is, The signal (sampling point) is applied with a gain by the multiplier

[0061] Calculate the signal energy of the sampling after applying the gain

[0062] Use this sampling point to affect the statistics of the average energy ( Filtering)

[0063] Compare the difference and update the gain

[0064] Among them, is the initial signal of the input sampling point, is the sampling point signal after applying the gain, represents the average signal energy of historical sampling points within a preset time window before update, represents the updated average signal energy, i.e., the gain average energy, represents the reference energy; is the filtering coefficient. The larger it is, the greater the influence of the new sampling point on the average energy and the faster the gain adjustment speed; is the gain adjustment coefficient. The larger it is, the more radical the gain adjustment.

[0065] It should be noted that after adding digital gain control, the impulse problem may become more prominent. However, in the embodiments of the present application, by comparing the signal energy of the sampling point with the reference energy and then performing processing, the influence of the impulse on the synchronization accuracy can be avoided. In addition, due to improving the control efficiency of the gain, the embodiments of the present application are beneficial to adjusting the gain to the target gain, i.e., the small gain, faster, thereby further improving the accuracy of signal synchronization.

[0066] In some embodiments, Figure 6 is the architecture diagram of the OFDM system provided by the embodiments of the present application. As Figure 6 shown, the initial digital signal is the output signal of the digital filter.

[0067] It should be noted that adding digital gain control after the digital filter can timely and quickly adjust the signal after digital filtering even under low signal-to-noise ratio, keep the signal energy within a certain range, and further avoid the interference of noise signals. The analog gain control needs to be determined according to the energy of the digital signal after analog-to-digital conversion. The analog signal includes out-of-band noise signals and in-band signals. The function of the analog filter is to filter out the out-of-band noise signals, so as to include the in-band signals. By comparing with the first threshold after analog-to-digital conversion, the analog gain can be adjusted in a timely manner. Under low signal-to-noise ratio, the intensities of the out-of-band noise and the in-band signals are similar. At this time, only analog gain control cannot meet the signal adjustment requirements. At this time, by adding digital gain control after the digital filter and adjusting the digital gain size by comparing the energy after gain with the second threshold, the digital signal energy can be adjusted within a suitable range. Here, the second threshold is the reference energy involved in the above embodiments.

[0068] In some embodiments, the carrier signal processing method may further include: If the ratio of the signal energy of the current sampling point to the minimum value of the average signal energies of the historical sampling points corresponding to multiple historical signal segments exceeds a preset ratio, then increase the filtering coefficient used when updating the current gain.

[0069] It should be noted that the filtering coefficient of automatic gain control in the related art is usually fixed. In the embodiments of the present application, the ratio between the signal energy of the current sampling point and the minimum value of the average signal energies of the historical sampling points corresponding to multiple historical signal segments is calculated and compared with a preset ratio. If the ratio exceeds the preset ratio, it can be considered that an impulse signal arrives under high signal-to-noise ratio. At this time, the filtering coefficient of digital gain control is increased, so as to achieve a faster gain adjustment speed, effectively reduce the range of the impulse signal, and thus be more conducive to subsequent synchronization processing.

[0070] In some embodiments, the carrier signal processing method may further include: If the ratio of the average signal energy of a preset number of consecutive sampling points in the current signal segment to the minimum value of the average signal energies of the historical sampling points corresponding to multiple historical signal segments exceeds the preset ratio, the gain adjustment coefficient used when updating the current gain is increased.

[0071] In the embodiments of the present application, the average signal energy of a preset number of consecutive sampling points reflects the overall energy situation of the continuously received sampling points. If it exceeds the preset ratio, it indicates that the preset number of sampling points is within the impulse signal range. At this time, by increasing the gain adjustment coefficient, the gain can be adjusted more aggressively, so that the energy of the effective signal can be adjusted to the appropriate range as soon as possible. In actual implementation, the preset ratio can be obtained by multiplying the signal-to-noise ratio under high signal-to-noise ratio by a certain expansion coefficient. The specific value of the expansion coefficient here can be set according to the signal type or actual communication situation, and the specific value of the signal-to-noise ratio here can be set according to actual requirements. The embodiments of the present application do not make specific limitations on this.

[0072] In some embodiments, step 130 may include: Based on the comparison result between the signal energy of the current sampling point and a preset saturation threshold, perform clipping processing on the signal energy of the current sampling point after amplitude suppression processing; the saturation threshold is less than the reference energy; Perform carrier synchronization processing based on the signal energy of the current sampling point after clipping processing.

[0073] It can be understood that considering that there may be a situation where the impulse degree of the sampling point is relatively low, the signal energy of the sampling point does not need to be set to zero, but it is desired to control the energy to be smaller. For this, in the embodiments of the present application, according to the comparison result between the signal energy of the current sampling point and a preset saturation threshold, further clipping processing is performed on the signal energy of the current sampling point obtained in step 120. Specifically, if it is determined that the signal energy of the current sampling point is greater than the saturation threshold, the signal energy of the current sampling point is suppressed to the saturation threshold, otherwise, the signal energy of the current sampling point remains unchanged; on this basis, carrier synchronization processing is performed to further weaken the influence brought by the impulse.

[0074] In some embodiments, the embodiments of the present application provide a novel digital gain control system, which avoids the impact of automatic gain control on synchronization by automatically detecting the sudden change (impulse) of the frame header energy caused by the previous-stage analog or the current-stage digital automatic gain control and eliminating this part of the signal. Figure 7 It is the second schematic flowchart of the carrier signal processing method based on the OFDM system provided by the embodiments of the present application. As Figure 7 shown, its main process is as follows. 1. After a new sampling point arrives, cache it for backup.

[0075] 2. Multiply the sampling point by the current gain, that is, apply the gain to the input.

[0076] 3. Calculate the signal energy of the sampling point.

[0077] 4. Calculate the new gain.

[0078] 4.1 Use the signal energy of the sampling point to affect the average signal energy of historical sampling points within a period of time ( filtering).

[0079] 4.2 Compare the signal energy of the sampling point with the average signal energy of historical sampling points within a period of time to obtain a difference.

[0080] 4.3 Scale the difference to obtain a new gain for calculating the signal energy of the next sampling point.

[0081] 5. Update the short-term cumulative energy (or short-term average energy) using the single-point signal energy.

[0082] 6. After meeting the condition of the number of input points, update the historical short-term cumulative energy using the short-term cumulative energy accumulated this time.

[0083] 7. Calculate the reference energy for comparing and judging impulses, that is, the impulse threshold, according to all historical short-term cumulative energies.

[0084] 8. Compare the magnitudes of the reference energy and the input single-point signal energy. If the latter is larger, it is considered that this point belongs to a part of the impulse, and set the corresponding output to 0. Otherwise, use the signal energy of the input point after applying the gain as the output of this point.

[0085] 9. Perform saturation judgment on the output through a limiter. If it is greater than a certain saturation threshold, set it to this value to further weaken the impact of the impulse; the saturation threshold here is less than the impulse threshold. It can be understood that if the impulse degree is low and the energy of the sampling point is not too high, the limiter can also be used for limiting at this time.

[0086] 10. Synchronize according to the processed signal to obtain the frame synchronization position (the ultimate goal is to achieve accurate synchronization).

[0087] Figure 8 It is the third schematic flowchart of the carrier signal processing method based on the OFDM system provided by the embodiments of the present application. Next, in combination with Figure 8 (n = 4), steps 5, 6, 7, and 8 will be further described.

[0088] For step 5 of updating the short-term cumulative energy, that is, maintaining a short-term cumulative energy and adding the calculated single-point energy each time. When the number of points is equal to the cumulative window length win_len, clear the short-term cumulative energy. Similarly, a short-term average energy can also be maintained. The difference is only that after the energy is accumulated, it is directly divided by the cumulative window length win_len to obtain the short-term average energy. The smallest one of the subsequent n historical short-term average energies is directly multiplied by the coefficient γ to obtain the reference energy. Here, the short-term average energy is the average signal energy in step 120.

[0089] For step 6 of updating the historical short-term cumulative energy, maintain n historical short-term cumulative energies Esum(n), and define the short-term cumulative energy in step 6 as Esum(0). When the number of points is equal to the cumulative window length win_len, make Esum(n) = Esum(n - 1). It should be noted that the input number of points in step 6 needs to cover the range of the number of points affected by the impulse, neither excessive nor too little. For example, the preamble symbol includes 10.5 SYNCP symbols, and each SYNCP symbol includes 1024 sampling points. Then the input number of points can be greater than or equal to the number of points of 1 SYNCP symbol, but less than (10.5 × 1024 / n), where n is the number of historical short-term cumulative energies.

[0090] For step 7 of calculating the reference energy, obtain the smallest historical short-term cumulative energy from the n historical short-term cumulative energies obtained in the previous step, divide it by the cumulative window length win_len and then multiply it by the coefficient γ to obtain the reference energy. The selection of γ should satisfy that the reference energy can represent the reasonable energy range of the normal signal as much as possible, that is, it is obtained by reasonably amplifying 1, and it can be specifically set according to the actual communication situation. It should be noted that this is the specific implementation method of obtaining the impulse threshold according to the historical short-term cumulative energy. Signal saturation means that the signal amplitude exceeds the maximum value that the system can represent during the processing, resulting in the signal being "clipped" or "limited", thereby introducing distortion. When the amplitude of the input signal exceeds this range, the system cannot correctly represent larger values, resulting in the peak of the signal being truncated and the waveform being distorted. For example, if the analog gain or digital gain is set too large, signal saturation may occur. The saturated signal will lose the detailed information of the original signal, introduce harmonic distortion, and affect the accuracy of subsequent digital signal processing.

[0091] As Figure 8 shown, taking n equal to 4 as an example, it is necessary to maintain 4 historical short-term cumulative energies, that is, the average signal energies corresponding to the 4 historical signal segments in step 120. The four corresponding time periods are a1, a2, a3, and a4, and the number of sampling points in each time period is equal. When the fifth time period reaches the cumulative number of sampling points, the corresponding updated time periods of the 4 historical short-term cumulative energies are a2, a3, a4, and a5. Here, the impulse threshold is calculated through the smallest historical short-term cumulative energy , so that the impulse sampling point can be judged according to the signal energy of the impulse sampling point and the impulse threshold comparison.

[0092] For the comparison and size judgment and erasure in step 8, that is, the energy of the sampling points exceeding the impulse threshold obtained in the previous step is set to 0, so as to complete the operation of filtering out impulses.

[0093] It should be noted that after the synchronization is successful, if the signal energy is maintained within a reasonable range, the automatic gain control will be locked, so that the amplitude of the signal is stable and at an appropriate level. At this time, the AGC has completed the adjustment of the signal amplitude and maintains this state; that is, when the AGC is locked, it indicates that the amplitude of the received signal has been successfully stabilized within the predetermined range and no further adjustment is required. It should be noted that after the AGC is locked, it will also monitor the amplitude of the received signal in real time. For the current data frame, generally no AGC adjustment will be performed on the current data frame after the AGC is locked, but for the next data frame, whether to adjust depends on the actual system requirements and application scenarios.

[0094] In power line carrier communication, digital gain control is used to dynamically adjust the amplitude of the received signal to adapt to input signals of different intensities and ensure that the signal is within an appropriate level range in subsequent processing (such as demodulation, synchronization, etc.). However, improper automatic gain control may cause signal saturation, that is, the signal amplitude exceeds the linear range that the system can handle, thus seriously affecting the detection and accuracy of the synchronization signal and reducing the reliability of the communication system. The embodiments of the present application can effectively avoid the problem of signal saturation, improve the synchronization performance and communication quality by optimizing the gain control algorithm, improving the signal processing circuit, and optimizing the synchronization signal design.

[0095] Embodiments of the present application avoid the impact of automatic gain control on synchronization by automatically detecting the sudden change (impulse) in the frame header energy caused by the previous-stage analog or the current-stage digital automatic gain control and eliminating this part of the signal. Embodiments of the present application are optimized for tracking speed and hardware implementation difficulty. Embodiments of the present application use automatic tracking to solve the impulse problem easily caused by automatic gain control and can also solve the impulse noise brought by the external channel; using multiple historical short-term cumulative energies can ensure that the calculated reference energy more likely represents the reasonable energy range of the real signal on the basis of increasing the tracking sensitivity.

[0096] The following introduces the technical terms involved in the embodiments of the present application.

[0097] In-band signal: The part within the expected effective signal bandwidth (specified by the physical layer communication protocol in the dual-mode communication interconnection and interoperability technical specification) of the received signal.

[0098] Contents related to signal saturation I. Definition and manifestations of signal saturation Signal saturation means that the amplitude of the input signal exceeds the dynamic range of the analog-to-digital converter (ADC) or the subsequent processing circuit, resulting in the flattening of the signal peak and waveform distortion. The specific manifestations are as follows: Waveform distortion: The peak of the signal is truncated, causing the original sine wave or pulse wave to become a flat-topped wave.

[0099] Harmonic distortion: The saturated signal will generate high-order harmonics, interfering with the spectrum of the original signal.

[0100] Information loss: Saturation will cause the loss of detailed information of the signal, especially the high-frequency components of the signal.

[0101] II. Impact of signal saturation on synchronization signals Synchronization signals (such as frame synchronization, carrier synchronization, etc.) are key signals in power line carrier communication to ensure the clock consistency and frame structure alignment between the transceiver parties. Signal saturation will have the following adverse effects on synchronization signals: (1) Failure to detect synchronization signals Loss of synchronization header: Synchronization signals usually contain specific synchronization headers (such as preambles, training sequences, etc.) for the receiving end to detect and lock synchronization. If the synchronization header signal is saturated, its waveform distortion will cause the receiving end to be unable to correctly identify the synchronization header, thus unable to establish synchronization.

[0102] Failure of threshold detection: The detection of synchronization signals is usually based on threshold comparison (such as zero-crossing detection, amplitude threshold detection, etc.). The amplitude of the saturated signal is flattened, which may cause the detection threshold to fail to trigger correctly, resulting in synchronization failure.

[0103] (2) Decrease in synchronization accuracy Phase offset: The harmonic distortion of the saturated signal will cause the signal phase to shift, affecting the accuracy of carrier synchronization.

[0104] Timing error: The timing information of the synchronization signal (such as frame boundary, symbol boundary) depends on the accurate amplitude and phase of the signal. The saturated signal will cause the accumulation of timing errors and reduce the synchronization accuracy.

[0105] (3) Increase in bit error rate Synchronization error propagation: Errors in the synchronization signal will cause demodulation errors in subsequent data frames, thereby increasing the bit error rate.

[0106] Decrease in signal-to-noise ratio: The harmonic distortion of the saturated signal will introduce additional noise, reducing the signal-to-noise ratio (SNR) and further deteriorating the communication performance.

[0107] III. Solutions to signal saturation To avoid the impact of signal saturation on the synchronization signal, the following measures can be taken: (1) Optimization of dynamic gain control Automatic gain control (AGC): By real-time monitoring of the amplitude of the input signal, dynamically adjust the gain to ensure that the signal amplitude is always within the linear range of the ADC.

[0108] Fast response mechanism: The AGC should have the ability to respond quickly to adapt to the rapid changes in signal strength in power line carrier communication.

[0109] (2) Signal clipping and filtering Soft clipper: Add a soft clipper before the ADC to non-linearly compress the signal exceeding the threshold to avoid waveform distortion caused by hard clipping.

[0110] Low-pass filtering: Filter out high-frequency harmonics through a low-pass filter to reduce the harmonic interference of the saturated signal.

[0111] (3) Optimization of synchronization signal design Redundancy design: Add redundant information (such as repeated synchronization headers, check codes, etc.) to the synchronization signal to improve the anti-interference ability of the synchronization signal.

[0112] Adaptive synchronization algorithm: Adopt an adaptive synchronization algorithm to dynamically adjust synchronization parameters (such as synchronization threshold, synchronization window, etc.) according to the signal quality.

[0113] (4) Improvement of receiver design Multistage amplification and attenuation: Adopt a multistage amplification and attenuation structure in the receiver to flexibly adjust the signal amplitude.

[0114] Digital signal processing (DSP): Post-process the saturated signal through DSP algorithms to recover some distorted information.

[0115] The carrier signal processing method based on the OFDM system provided by the embodiments of the present application may have a carrier signal processing device based on the OFDM system as the execution subject. In the embodiments of the present application, taking the carrier signal processing device based on the OFDM system to execute the carrier signal processing method based on the OFDM system as an example, the carrier signal processing device provided by the embodiments of the present application is described.

[0116] The embodiments of the present application also provide a carrier signal processing device based on the OFDM system. Figure 9 It is the structural diagram of the carrier signal processing device based on the OFDM system provided by the embodiments of the present application. As Figure 9 shown, the carrier signal processing device includes: a sampling point acquisition module 910, a sampling point processing module 920, and a synchronization processing module 930.

[0117] The sampling point acquisition module 910 is configured to acquire the signal energy of the current sampling point within the current signal segment in the digital signal; The sampling point processing module 920 is configured to perform amplitude suppression processing on the signal energy of the current sampling point based on the comparison result between the signal energy of the current sampling point and the reference energy; the reference energy is determined based on the average signal energy of the historical sampling points respectively corresponding to multiple historical signal segments in the digital signal, and the number of sampling points in each signal segment of the digital signal is the same; The synchronization processing module 930 is configured to perform carrier synchronization processing based on the signal energy of the current sampling point after amplitude suppression processing.

[0118] According to the carrier signal processing device provided by the embodiments of the present application, by automatically tracking the signal energy of each newly arrived sampling point, detecting impulse or pulse noise sampling points according to the comparison result between the signal energy and the reference energy, and filtering the impulse or pulse noise sampling points through amplitude suppression processing, the accuracy of signal synchronization is improved, and thus the reliability of the OFDM system is improved. In addition, by calculating the reference energy based on the average signal energy of the historical sampling points respectively corresponding to multiple historical signal segments, on the basis of increasing the tracking sensitivity, it is ensured that the calculated reference energy is more likely to represent the reasonable energy range of the real signal, thereby further improving the accuracy of signal synchronization.

[0119] The carrier signal processing device in the embodiments of the present application can be an electronic device or a component in an electronic device, such as an integrated circuit or a chip. The electronic device can be a terminal or other devices other than terminals. Exemplarily, the electronic device can be a mobile phone, a tablet computer, a laptop computer, a handheld computer, a vehicle-mounted electronic device, a Mobile Internet Device (MID), an augmented reality (AR) / virtual reality (VR) device, a robot, a wearable device, an ultra-mobile personal computer (UMPC), a netbook, or a personal digital assistant (PDA), etc., and can also be a server, a Network Attached Storage (NAS), a personal computer (PC), a television (TV), a teller machine, or a self-service machine, etc. The embodiments of the present application do not make specific limitations.

[0120] The carrier signal processing device in the embodiments of the present application can be a device with an operating system. The operating system can be the Microsoft (Windows) operating system, the Android operating system, the IOS operating system, or other possible operating systems. The embodiments of the present application do not make specific limitations.

[0121] The carrier signal processing device provided by the embodiments of the present application can implement Figures 3 to 8 each process implemented by the method embodiments. To avoid repetition, details are not described herein again.

[0122] In some embodiments, as Figure 10 shown, the embodiments of the present application further provide an electronic device 1000, including a processor 1001, a memory 1002, and a computer program stored on the memory 1002 and executable on the processor 1001. When the program is executed by the processor 1001, it implements each process of the above method embodiments for carrier signal processing based on the OFDM system and can achieve the same technical effects. To avoid repetition, details are not described herein again.

[0123] It should be noted that the electronic devices in the embodiments of the present application include the above-mentioned mobile electronic devices and non-mobile electronic devices.

[0124] The embodiments of the present application further provide a non-transitory computer-readable storage medium, on which a computer program is stored. When the computer program is executed by a processor, it implements each process of the above-mentioned embodiments of the carrier signal processing method based on the OFDM system, and can achieve the same technical effect. To avoid repetition, it will not be elaborated here.

[0125] Among them, the processor is the processor in the electronic device described in the above embodiments. The readable storage medium includes computer-readable storage media such as computer read-only memory ROM, random access memory RAM, magnetic disks or optical discs.

[0126] The embodiments of the present application further provide a computer program product, including a computer program. When the computer program is executed by a processor, it implements the above-mentioned carrier signal processing method based on the OFDM system.

[0127] Among them, the processor is the processor in the electronic device described in the above embodiments. The readable storage medium includes computer-readable storage media such as computer read-only memory ROM, random access memory RAM, magnetic disks or optical discs.

[0128] The embodiments of the present application further provide a chip, which includes a processor and a communication interface. The communication interface is coupled to the processor, and the processor is used to run programs or instructions to implement each process of the above-mentioned embodiments of the carrier signal processing method based on the OFDM system, and can achieve the same technical effect. To avoid repetition, it will not be elaborated here.

[0129] It should be understood that the chip mentioned in the embodiments of the present application may also be referred to as a system-on-chip, system chip, chip system or system-on-chip.

[0130] It should be noted that in this article, the term "including", "comprising" or any other variant thereof is intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements not only includes those elements, but also includes other elements not explicitly listed, or further includes elements inherent to such process, method, article or device. Without further limitation, an element defined by the statement "including one..." does not exclude the existence of another identical element in the process, method, article or device including the element. In addition, it should be pointed out that the methods and devices in the embodiments of the present application are not limited to performing functions in the order shown or discussed, and may also include performing functions in a substantially simultaneous manner or in a reverse order according to the functions involved. For example, the described methods may be performed in an order different from that described, and various steps may be added, omitted, or combined. In addition, the features described with reference to certain examples may be combined in other examples.

[0131] Through the description of the above embodiments, those skilled in the art can clearly understand that the above-described example methods can be implemented by means of software plus a necessary general hardware platform. Of course, they can also be implemented by hardware, but in many cases the former is a better implementation. Based on such an understanding, the technical solution of the present application, in essence, or the part that contributes to the relevant technology, can be embodied in the form of a computer software product. The computer software product is stored in a storage medium (such as ROM / RAM, magnetic disk, optical disk) and includes several instructions for causing a terminal (which can be a mobile phone, computer, server, or network device, etc.) to execute the methods described in various embodiments of the present application.

[0132] The embodiments of the present application have been described above in conjunction with the accompanying drawings. However, the present application is not limited to the above specific embodiments. The above specific embodiments are merely illustrative and not restrictive. Under the inspiration of the present application, those of ordinary skill in the art can also make many forms without departing from the purpose of the present application and the scope protected by the claims, and all of them fall within the protection scope of the present application.

[0133] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "illustrative embodiments", "examples", "specific examples", or "some examples", etc. means that the specific features, structures, materials, or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0134] Although the embodiments of the present application have been shown and described, those of ordinary skill in the art can understand that various changes, modifications, substitutions, and variations can be made to these embodiments without departing from the principles and purposes of the present application. The scope of the present application is defined by the claims and their equivalents.

Claims

1. A method for processing carrier signals based on an OFDM system, characterized in that Including: Obtaining the signal energy of the current sampling point within the current signal segment in the digital signal; Performing amplitude suppression processing on the signal energy of the current sampling point based on the comparison result between the signal energy of the current sampling point and the reference energy; The reference energy is determined based on the average signal energy of the historical sampling points corresponding to multiple historical signal segments in the digital signal, and the number of sampling points in each signal segment of the digital signal is the same; Performing carrier synchronization processing based on the signal energy of the current sampling point after amplitude suppression processing.

2. The carrier signal processing method based on an OFDM system according to claim 1, characterized in that, The performing amplitude suppression processing on the signal energy of the current sampling point based on the comparison result between the signal energy of the current sampling point and the reference energy includes: If the signal energy of the current sampling point is greater than the reference energy, setting the signal energy of the current sampling point to zero; if the signal energy of the current sampling point is less than or equal to the reference energy, keeping the signal energy of the current sampling point unchanged.

3. The carrier signal processing method based on an OFDM system according to claim 1, wherein The reference energy is determined based on the minimum value among the average signal energies of the historical sampling points corresponding to the multiple historical signal segments.

4. The carrier signal processing method based on an OFDM system according to claim 1, wherein The number of sampling points in each signal segment of the digital signal is determined based on the number of synchronization preamble symbols included in the preamble signal corresponding to the digital signal and the number of sampling points included in the synchronization preamble symbols.

5. The carrier signal processing method based on an OFDM system according to claim 4, wherein The number of sampling points in each signal segment of the digital signal is greater than or equal to the number of sampling points included in the synchronization preamble symbols; the total number of sampling points of the multiple historical signal segments is less than the product value of the number of synchronization preamble symbols and the number of sampling points included in the synchronization preamble symbols.

6. The carrier signal processing method based on the OFDM system according to claim 1, characterized in that The obtaining the signal energy of the current sampling point within the current signal segment in the digital signal includes: Obtaining the initial signal energy of the current sampling point in the initial digital signal; Multiplying the initial signal energy of the current sampling point by the current gain to obtain the signal energy of the current sampling point; the current gain is updated based on the signal energy of the previous sampling point before the current sampling point.

7. The carrier signal processing method based on an OFDM system according to claim 6, wherein The initial digital signal is the output signal of a digital filter.

8. The carrier signal processing method based on an OFDM system according to any one of claims 1 to 7, characterized in that The performing carrier synchronization processing based on the signal energy of the current sampling point after amplitude suppression processing includes: Performing clipping processing on the signal energy of the current sampling point after amplitude suppression processing based on the comparison result between the signal energy of the current sampling point and a preset saturation threshold; the saturation threshold is less than the reference energy; Performing carrier synchronization processing based on the signal energy of the current sampling point after clipping processing.

9. A carrier signal processing device based on an OFDM system, characterized in that, Including: A sampling point acquisition module for obtaining the signal energy of the current sampling point within the current signal segment in the digital signal; A sampling point processing module for performing amplitude suppression processing on the signal energy of the current sampling point based on the comparison result between the signal energy of the current sampling point and the reference energy; The reference energy is determined based on the average signal energy of the historical sampling points corresponding to multiple historical signal segments in the digital signal, and the number of sampling points in each signal segment of the digital signal is the same; A synchronization processing module for performing carrier synchronization processing based on the signal energy of the current sampling point after amplitude suppression processing.

10. An electronic device, comprising a memory, a processor, and a computer program stored on the memory and executable on the processor, characterized in that, When the processor executes the program, it implements the carrier signal processing method based on the OFDM system according to any one of claims 1-8.

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