Synchronization method and system for power line carrier communication and electronic equipment

Abstract

The invention provides a synchronization method and system for power line carrier communication and electronic equipment, and the method comprises the steps: obtaining signal data of a sender in power line carrier communication, and processing the signal data to obtain a plurality of data frames; inserting a leader sequence at an initial position in a data frame to generate a marked data frame; acquiring a local sequence of a sender, and performing convolution calculation on the marked data frame and the local sequence to obtain a convolution value; judging whether the convolution value exceeds a preset threshold value or not, and if yes, determining the position exceeding the threshold value as a peak value position; intercepting a marked data segment according to the peak value position, and performing autocorrelation calculation on the marked data segment to determine the initial position of the data frame; and enabling the receiver to receive the data frames from the starting position of each data frame. The problem of insufficient high-precision synchronization rate in power line carrier communication is solved.

Description

Technical Field

[0001] This application relates to the field of communication technology, and in particular to synchronization methods, systems and electronic devices for power line carrier communication. Background Technology

[0002] Power line communication (PLC) technology is a unique communication method in power systems. PLC communication utilizes existing power line resources as the carrier for high-frequency carrier signal transmission, offering advantages such as no wiring required, simplicity, practicality, and low cost. Distribution network protection and control services have high requirements for real-time and reliability of data transmission, demanding that two interconnected protection devices guarantee time synchronization with an accuracy of <10µs. Synchronization technology is a critical technology in communication systems, significantly impacting the overall system performance. However, with the large-scale integration of distributed power sources into the grid, synchronization detection performance is significantly affected.

[0003] High-speed power line carrier communication technology based on orthogonal frequency division multiplexing (OFDM) is very sensitive to timing and synchronization errors. Even a small error can degrade system performance. Synchronization time requires microsecond-level rapid acquisition; otherwise, the communication transmission rate will be greatly reduced. Summary of the Invention

[0004] In view of this, the purpose of this application is to propose a synchronization method, system and electronic equipment for power line carrier communication, which solves the problem of insufficient high-precision synchronization rate in power line carrier communication.

[0005] To achieve one of the aforementioned objectives, this application provides a synchronization method for power line carrier communication, the method comprising:

[0006] Acquire signal data from the transmitter in power line carrier communication, and process the signal data to obtain multiple data frames; A preamble sequence is inserted at the beginning position of a data frame to generate a marked data frame; Obtain the sender's local sequence, perform convolution calculation on the marked data frame and the local sequence, and obtain the convolution value; Determine whether the convolution value exceeds a preset threshold value; if so, determine the position exceeding the threshold value as the peak position. Based on the peak position, a marked data segment is extracted, and autocorrelation calculation is performed on the marked data segment to determine the starting position of the data frame; The receiver is instructed to begin receiving the data frame from the beginning position of each data frame.

[0007] As a further improvement to one embodiment of this application, the step of inserting a preamble sequence at the beginning position of a data frame to generate a marked data frame includes: A preamble sequence is inserted at the beginning of the data frame. The preamble sequence includes two orthogonal frequency division multiplexing symbols. Generate a constant amplitude zero autocorrelation sequence according to the following formula: ; Where c(k) is the constant amplitude zero autocorrelation sequence, N is the length of the constant amplitude zero autocorrelation sequence, k is the discrete index of the constant amplitude zero autocorrelation sequence, and exp(j) is the complex exponential function; The same constant amplitude zero autocorrelation sequence is placed in both of the orthogonal frequency division multiplexing symbols.

[0008] As a further improvement to one embodiment of this application, the convolution calculation on the labeled data frame and the local sequence includes: A search window is set, the length of which is the same as the length of the constant amplitude zero autocorrelation sequence; The search window is slid across the marked data frame multiple times; Perform convolution calculations on the data segments captured by each sliding of the search window and the local sequence; After determining whether the convolution value exceeds a preset threshold, the method further includes: If not, the search window slides again, and the data segment and the local sequence are convolved again to obtain a new convolution value.

[0009] As a further improvement to one embodiment of this application, the convolution calculation on the labeled data frame and the local sequence includes: The convolution calculation is performed according to the following formula: ; ; ; ; Where P(t×N+n) is the normalized cross-correlation value, N is the length of the constant amplitude zero autocorrelation sequence, r(·) is the data segment, c(·) is the local sequence, and c (·) is the conjugate complex number of the constant amplitude zero autocorrelation sequence, t is the number of times the search window slides, R(t×N) is the amplitude of the marked data frame, and W(·) is the cross-correlation value.

[0010] As a further improvement to one embodiment of this application, the convolution calculation on the labeled data frame and the local sequence includes: The data segment is processed using Fourier transform technology to convert it into frequency domain data; The frequency domain data is multiplied by the local sequence to obtain an intermediate value. The intermediate value is then converted into time domain data using the Fourier transform technique, and the time domain data is used as the convolution value.

[0011] As a further improvement to one embodiment of this application, before determining whether the convolution value exceeds a preset threshold, the following steps are included: If the current data frame has a frame number of 1 in the signal data, then set an initial threshold value; If the frame number of the current data frame in the signal data is greater than 1, then the preset threshold value and the power of the peak value in the previous data frame are obtained. Determine whether the power is between the preset maximum and minimum threshold values; If so, it is determined that the threshold value of the current data frame is the same as the threshold value of the previous data frame; If not, the power of the peak value in the previous data frame is reduced by a preset factor to obtain the threshold value of the current data frame.

[0012] As a further improvement to one embodiment of this application, the step of extracting the marked data segment based on the peak position includes: Two marked data segments are extracted based on the peak position. The position of the first marked data segment is represented as follows: p~p+N; The location of the second marked data segment is represented as follows: p+N f ~p+N+N f ; Where p is the peak position, and N is the length of the constant amplitude zero autocorrelation sequence. f The length of the orthogonal frequency division multiplexing symbol is given.

[0013] As a further improvement to one embodiment of this application, the step of performing autocorrelation calculation on the marked data segment to determine the start position of the data frame includes: The starting position of the data frame is calculated using the following formula: ; ; ; in, N represents the starting position of the data frame. CP Let r be the length of the cyclic prefix, and r(·) be the data segment. (·) represents the conjugate complex number of the data segment, and R(p) represents the amplitude at the peak position. is the preset threshold value, and W(·) is the cross-correlation value.

[0014] Based on the same inventive concept, this application also provides a synchronization system for power line carrier communication, comprising: The acquisition module is used to acquire signal data from the transmitter in power line carrier communication and process the signal data to obtain multiple data frames. An insertion module is used to insert a preamble sequence at the beginning position of a data frame to generate a marked data frame; The convolution calculation module is used to obtain the sender's local sequence, perform convolution calculation on the marked data frame and the local sequence, and obtain the convolution value; The judgment module is used to determine whether the convolution value exceeds a preset threshold value. If so, the position that exceeds the threshold value is determined as the position of the peak value. The autocorrelation calculation module is used to extract a marked data segment based on the position of the peak value, and perform autocorrelation calculation on the marked data segment to determine the starting position of the data frame; The receiving module enables the receiver to begin receiving the data frame from the beginning position of each data frame.

[0015] Based on the same inventive concept, this application also provides an electronic device, including: a processor and a memory; the memory stores a computer program, which, when executed by the processor, causes the processor to perform the steps of the synchronization method for power line carrier communication.

[0016] Compared with existing technologies, the technical advantages of this invention are as follows: by using convolution and autocorrelation calculations, the starting position of the data frame can be captured quickly. After convolution calculation, a sharp peak is obtained, which ensures the accuracy of synchronization and improves the anti-noise interference performance. At the same time, the detection speed is greatly reduced compared with traditional correlation algorithms, that is, the frame header capture time is shortened, and microsecond-level fast synchronization can be achieved, ensuring the real-time and reliability requirements of power line carrier communication for new power distribution network protection and control services. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in this application or related technologies, the drawings used in the description of the implementation methods or related technologies will be briefly introduced below. Obviously, the drawings described below are only the implementation methods of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0018] Figure 1 A flowchart illustrating a synchronization method for power line carrier communication provided in one embodiment of this application; Figure 2 A schematic diagram of a leader sequence provided in one embodiment of this application; Figure 3 A schematic diagram of a synchronization system for power line carrier communication provided for an embodiment of this application; Figure 4 This is a schematic diagram of the hardware structure of an electronic device provided for an embodiment of this application. Detailed Implementation

[0019] The present invention will now be described in detail with reference to the specific embodiments shown in the accompanying drawings. However, these embodiments do not limit the present invention, and any structural, methodological, or functional modifications made by those skilled in the art based on these embodiments are included within the scope of protection of the present invention.

[0020] It should be noted that, unless otherwise defined, the technical or scientific terms used in the embodiments of this application should have the ordinary meaning understood by those skilled in the art to which this application pertains. The terms "first," "second," and similar terms used in the embodiments of this application do not indicate any order, quantity, or importance, but are merely used to distinguish different components. Terms such as "comprising" or "including" mean that the element or object preceding the word encompasses the elements or objects listed following the word and their equivalents, without excluding other elements or objects.

[0021] Power line communication (PLC) is a unique communication method in power systems. PLC communication utilizes existing power line resources as the carrier for high-frequency carrier signals to transmit data signals. Currently, PLC technology is widely used in non-real-time data acquisition services such as power information collection. With the construction of new power systems, PLC technology has been applied in production operations such as protection and control, and automation of new distribution networks to address the problem of insufficient coverage of power fiber optic and wireless private networks. Unlike power data acquisition (such as meter reading), distribution network protection and control services have extremely high requirements for the real-time performance and reliability of data transmission, especially in distribution network current differential protection. Since the judgment of current difference needs to be based on the current value at the same moment, the two interconnected protection devices must ensure time synchronization, with a time synchronization accuracy of <10µs. To achieve rapid fault detection and isolation, the transmission delay of interactive information must not exceed 12ms, placing extremely high demands on the high speed, time synchronization, and reliability of communication.

[0022] Synchronization technology is a key technology in communication systems, significantly impacting overall system performance. Typically, carrier communication uses a preamble sequence for autocorrelation or cross-correlation calculations to detect bursty data packets and achieve synchronization. The preamble sequence contains several identical parts, and this repetitive structure is used for a two-step synchronization operation: coarse synchronization (autocorrelation) and fine synchronization (cross-correlation). Coarse synchronization quickly captures a rough estimate of the data packet's start position. Based on this rough estimate, fine synchronization performs cross-correlation to obtain a more precise data packet start position. This synchronization detection method is highly effective for low-speed PLC communication systems, with synchronization acquisition time controllable within 1-3ms.

[0023] With the large-scale integration of distributed power sources into the power grid, the power line carrier channel has become more complex and variable. Factors such as amplitude nonlinearity, narrowband interference, and impulse noise in the power line channel can significantly affect synchronization detection performance, even preventing it from functioning properly. On the other hand, high-speed power line carrier communication technology based on Orthogonal Frequency Division Multiplexing (OFDM) is extremely sensitive to timing synchronization errors; even small errors can degrade system performance. Synchronization time requires microsecond-level rapid acquisition; otherwise, the communication transmission rate will be significantly reduced.

[0024] To address the aforementioned problems, this application provides a synchronization method for power line carrier communication, such as... Figure 1 As shown, it includes the following steps: Step S100: Obtain the signal data of the sender in the power line carrier communication, and process the signal data to obtain multiple data frames.

[0025] Specifically, the signal data is divided into multiple data frames. The data frame is the core transmission unit of the physical layer. It is a structured data block that encapsulates the high-speed data stream according to the transmission characteristics of orthogonal frequency division multiplexing technology. It is also the basis for synchronization, tuning and decoding between the sender and receiver.

[0026] Step S200: Insert a preamble sequence at the beginning position of a data frame to generate a marked data frame.

[0027] Specifically, adding a preamble sequence at the beginning of a data frame is equivalent to adding a precisely located start to the data frame. This marked data frame is used during subsequent synchronization to allow the receiver to quickly and accurately locate the start of the frame, correct transmission deviations, ensure synchronization accuracy, and adapt to the high-speed transmission characteristics of orthogonal frequency division multiplexing (OFDM) technology.

[0028] In one possible implementation of this application, step S200 includes: Step S210: Insert a preamble sequence at the beginning position of the data frame. The preamble sequence includes two orthogonal frequency division multiplexing symbols.

[0029] Step S220: Generate a constant amplitude zero autocorrelation sequence according to the following formula: ; Where c(k) is a constant amplitude zero autocorrelation sequence, N is the length of the constant amplitude zero autocorrelation sequence, k is the discrete index of the constant amplitude zero autocorrelation sequence, and exp(j) is a complex exponential function.

[0030] Specifically, constant amplitude zero autocorrelation sequences have a constant amplitude. For example, when c(k) = 1, the sender does not need amplitude adjustment, avoiding power fluctuations and improving the sender's transmission efficiency. Constant amplitude zero autocorrelation sequences also have ideal autocorrelation characteristics, which can accurately locate the boundaries of data frames in subsequent steps; they also have Fourier transform invariance, making them suitable for convolution calculations in subsequent steps.

[0031] Step S230: Place the same constant amplitude zero autocorrelation sequence in the two orthogonal frequency division multiplexing symbols.

[0032] Specifically, using two identical orthogonal frequency division multiplexing (OFDM) symbols in the preamble sequence is an enhancement of a single OFDM symbol. The receiver performs a sliding cross-correlation on the two repeated OFDM symbols, which, compared to a single symbol, can suppress channel noise and multipath interference, make the synchronization peak sharper, and improve the robustness of time synchronization. The frequency deviation of the signal is corrected based on the phase change of the two repeated symbols. Ultimately, the receiver can quickly and accurately complete frame synchronization and channel compensation under high-speed and complex channels, laying the foundation for high-speed and reliable transmission of subsequent data frames.

[0033] Step S300: Obtain the sender's local sequence, perform convolution calculation on the marked data frame and the local sequence to obtain the convolution value.

[0034] Specifically, the first step is to perform peak search by convolving the labeled data frames with added preamble sequences to obtain sharp peaks.

[0035] In one possible implementation of this application, step S300 includes: Step S310: Set the search window, the length of which is the same as the length of the constant amplitude zero autocorrelation sequence.

[0036] Step S320 involves sliding the search window multiple times over the marked data frame.

[0037] Step S330: Perform convolution calculation on the data segment and local sequence captured each time the search window slides.

[0038] Specifically, because the length of the search window is the same as the length of the constant amplitude zero autocorrelation sequence, when the sliding window passes through the constant amplitude zero autocorrelation sequence multiple times, the signal received by the receiver is equal to the signal output by the transmitter. For example... Figure 2 As shown, the leader sequence includes two constant amplitude zero autocorrelation sequences (CAZAC). When the search window slides over the leader sequence, four peaks (F1, F2, F3, and F4) appear, representing the following: the search window completely covers the first constant amplitude zero autocorrelation sequence; the search window completely covers the tail copy (CP) of the first constant amplitude zero autocorrelation sequence; the search window completely covers the second constant amplitude zero autocorrelation sequence (CAZAC); and the search window completely covers the tail copy (CP) of the second constant amplitude zero autocorrelation sequence. The leader sequence can be accurately identified based on these peaks.

[0039] In one possible implementation of this application, step S330 includes: Step S331: Perform convolution calculation according to the following formula: ; ; ; ; Where P(t×N+n) is the normalized cross-correlation value, N is the length of the constant amplitude zero autocorrelation sequence, r(·) is the data segment, c(·) is the local sequence, and c (·) is the conjugate complex number of the constant amplitude zero autocorrelation sequence, t is the number of times the search window slides, and R(t×N) is the amplitude of the marked data frame.

[0040] W(t×N+n) is the received signal r( ) and local CAZAC sequence c( The sliding cross-correlation of t is mathematically equivalent to convolution; R(t×N) is the amplitude of the labeled data frame, and the denominator in the formula is the energy normalization factor of the labeled data frame, which eliminates the influence of amplitude fluctuations in the received signal, makes the cross-correlation value a normalized value between 0 and 1, and allows signal blocks of different energies to be compared in terms of peak value.

[0041] In another possible implementation of this application, step S330 includes: Step S332: Use Fourier transform technology to process the data segment and convert the data segment into frequency domain data.

[0042] Step S333: Multiply the frequency domain data with the local sequence to obtain an intermediate value, and use Fourier transform technology to convert the intermediate value into time domain data, using the time domain data as the convolution value.

[0043] Specifically, the convolution algorithm is implemented through frequency domain multiplication. The FFT (Fast Fourier Transform) unit transforms the data segment truncated by the search window into the frequency domain and multiplies it with the local sequence stored in the read-only memory (ROM) unit. Finally, the output of the multiplier is transformed back to the time domain using the Inverse Fast Fourier Transform (IFFT) unit. The FFT / IFFT unit can be configured as a pipelined type, resulting in a time interval of N clock cycles between two convolution calculations. Since each convolution calculation can detect whether N sampling points are at the start of a frame, its detection rate is 1 sampling point / clock cycle, which equals the input signal rate, enabling fast synchronization signal search.

[0044] Step S400: Determine whether the convolution value exceeds a preset threshold. If so, determine the position that exceeds the threshold as the peak position.

[0045] In one possible implementation of this application, after determining whether the convolution value exceeds a preset threshold in step S400, the method further includes: If not, the search window will slide again, and the data segment and local sequence will be convolved again to obtain a new convolution value.

[0046] Specifically, the comparison function in the peak search step is to find peaks that exceed the threshold. If the convolutional value does not exceed the threshold, the search window slides N sampling points to continue the previous operation; otherwise, a pulse signal is generated to activate the peak judgment module to start working and determine the peak position.

[0047] In one possible implementation of this application, in order to further reduce the impact of input signal fluctuations on synchronous detection performance, a dynamic threshold value needs to be set before step S400, including: If the current data frame has a frame number of 1 in the signal data, then set the initial threshold value; Step S401: If the frame number of the current data frame in the signal data is greater than 1, then obtain the preset threshold value and the peak power in the previous data frame.

[0048] Step S402: Determine whether the power is between the preset maximum threshold and minimum threshold.

[0049] Step S403: If so, determine that the threshold value of the current data frame is the same as the threshold value of the previous data frame.

[0050] Step S404: If not, reduce the power of the peak value in the previous data frame by a preset factor to obtain the threshold value of the current data frame.

[0051] In another possible implementation of this application, a fixed threshold value needs to be set before step S400.

[0052] Step S500: Extract the marked data segment based on the peak position, and perform autocorrelation calculation on the marked data segment to determine the starting position of the data frame.

[0053] In one possible implementation of this application, step S500 includes: Step S510: Extract two marked data segments based on the peak position. The position of the first marked data segment is represented as follows: p~p+N; The location of the second marked data segment is represented as follows: p+N f ~p+N+N f ; Where p is the peak position, N is the length of the constant amplitude zero autocorrelation sequence, and N f The length of the orthogonal frequency division multiplexing symbol.

[0054] In one possible implementation of this application, step S500 further includes: The start position of the data frame is calculated using the following formula: ; ; ; in, N represents the start position of the data frame. CP The length of the cyclic prefix is ​​r, and r(·) is the data segment. (·) represents the conjugate complex number of the data segment, and R(p) represents the amplitude at the peak position. is the preset threshold value, and W(·) is the cross-correlation value.

[0055] In one possible implementation of this application, step S500 completes the autocorrelation extremes and interchange calculation of the data segment, which mainly consists of a multiplier and an accumulator. The output of the accumulator is stored in two registers, one of which serves as the output of the power calculation module and the other as the input of the accumulator. The register is cleared every N clock cycles, so that the power of the data segment with a length of N can be calculated continuously.

[0056] In one possible implementation of this application, step S500 determines whether the normalized cross-correlation value exceeds a set threshold. Because the correlation calculation is performed only once in the peak value determination, the threshold can be set to a fixed value.

[0057] Step S600: The receiver starts receiving data frames from the beginning position of each data frame.

[0058] Specifically, the receiver accurately locates the starting position of each data frame in the communication data, that is, knows the position where the data frame reception begins, so that the time and frequency of the transceiver devices are perfectly aligned, and communication is achieved in high-speed orthogonal frequency division multiplexing technology.

[0059] This method, through convolution and autocorrelation calculations, can quickly capture the start position of data frames. It improves the accuracy and noise immunity of high-speed PLC communication systems based on OFDM technology. Furthermore, its detection speed is N times (training sequence length) times faster than traditional correlation algorithms, significantly reducing frame header capture time and enabling microsecond-level rapid synchronization, thus ensuring the real-time and reliability requirements of power distribution network protection and control services.

[0060] Among them, the synchronization peak detection based on circular convolution combines convolution calculation and autocorrelation calculation in the synchronization algorithm, resulting in sharp peaks and excellent synchronization performance, with strong anti-noise and interference characteristics. The detection rate of this method is N times that of traditional correlation algorithms, which reduces the capture time at the frame start position and saves processing time in the implementation process. It is suitable for high-speed orthogonal frequency division multiplexing communication signal synchronization detection, realizing fast synchronization and high-speed carrier communication.

[0061] Another embodiment of this application discloses a synchronization system for power line carrier communication, such as... Figure 3 As shown, it includes the following modules: The acquisition module is used to acquire signal data from the sender in power line carrier communication and process the signal data to obtain multiple data frames.

[0062] The insertion module is used to insert a preamble sequence at the beginning of a data frame to generate a marked data frame.

[0063] The convolution calculation module is used to obtain the sender's local sequence, perform convolution calculation on the marked data frame and the local sequence, and obtain the convolution value.

[0064] The judgment module is used to determine whether the convolution value exceeds a preset threshold. If so, the position that exceeds the threshold is determined as the position of the peak value.

[0065] The autocorrelation calculation module is used to extract marked data segments based on the position of the peak value, and perform autocorrelation calculation on the marked data segments to determine the starting position of the data frame.

[0066] The receiving module enables the receiver to begin receiving data frames from the beginning of each data frame.

[0067] In one possible implementation of this application, the insertion module includes: The sub-insertion module is used to insert a preamble sequence at the beginning of the data frame. The preamble sequence consists of two orthogonal frequency division multiplexing symbols. The sequence generation module is used to generate constant amplitude zero-autocorrelation sequences according to the following formula: ; Where c(k) is a constant amplitude zero autocorrelation sequence, N is the length of the constant amplitude zero autocorrelation sequence, k is the discrete index of the constant amplitude zero autocorrelation sequence, and exp(j) is a complex exponential function; Placement module, used to place the same constant amplitude zero autocorrelation sequence in two orthogonal frequency division multiplexing symbols.

[0068] In one possible implementation of this application, the convolution calculation module includes: The settings module is used to set the search window, the length of which is the same as the length of the constant amplitude zero autocorrelation sequence. The sliding module is used to allow the search window to slide multiple times on the marked data frame; The first calculation module is used to perform convolution calculations on the data segments and local sequences captured each time the search window slides; The sliding module is also used for: If not, the search window will slide again, and the data segment and local sequence will be convolved again to obtain a new convolution value.

[0069] In one possible implementation of this application, the first computing module includes: Convolution is performed using the following formula: ; ; ; ; Where P(t×N+n) is the normalized cross-correlation value, N is the length of the constant amplitude zero autocorrelation sequence, r(·) is the data segment, c(·) is the local sequence, and c (·) is the conjugate complex number of the constant amplitude zero autocorrelation sequence, t is the number of times the search window slides, R(t×N) is the amplitude of the marked data frame, and W(·) is the cross-correlation value.

[0070] In one possible implementation of this application, the first computing module includes: The Fourier transform module is used to process data segments using Fourier transform technology, converting the data segments into frequency domain data. The multiplier multiplies the frequency domain data with the local sequence to obtain an intermediate value; The inverse Fourier transform module is used to convert intermediate values ​​into time-domain data using Fourier transform techniques, and then use the time-domain data as convolution values.

[0071] One possible implementation of this application also includes: The initial module is used to set the initial threshold value if the current data frame has a frame number of 1 in the signal data. The sub-acquisition module, if the frame number of the current data frame in the signal data is greater than 1, is used to acquire the preset threshold value and the peak power in the previous data frame. The sub-judgment module is used to determine whether the power is between the preset maximum threshold and minimum threshold. If so, then the threshold value of the current data frame is determined to be the same as the threshold value of the previous data frame; If not, the power of the peak value in the previous data frame is reduced by a preset factor to obtain the threshold value of the current data frame.

[0072] In one possible implementation of this application, the autocorrelation calculation module includes: The extraction module is used to extract two marked data segments based on the peak position. The position of the first marked data segment is represented as follows: p~p+N; The location of the second marked data segment is represented as follows: p+N f ~p+N+N f Where p is the peak position, and N is the length of the constant amplitude zero autocorrelation sequence. f The length of the orthogonal frequency division multiplexing symbol.

[0073] In one possible implementation of this application, the autocorrelation calculation module includes: The second calculation module is used to calculate the start position of the data frame according to the following formula: ; ; ; in, N represents the start position of the data frame. CP The length of the cyclic prefix is ​​r, and r(·) is the data segment. (·) represents the conjugate complex number of the data segment, and R(p) represents the amplitude at the peak position. is the preset threshold value, and W(·) is the cross-correlation value.

[0074] Figure 4 This diagram illustrates a more specific hardware structure of an electronic device provided in this embodiment. The device may include: a processor 1010, a memory 1020, an input / output interface 1030, a communication interface 1040, and a bus 1050. The processor 1010, memory 1020, input / output interface 1030, and communication interface 1040 are interconnected internally via the bus 1050.

[0075] The processor 1010 can be implemented using a general-purpose CPU (Central Processing Unit), microprocessor, application-specific integrated circuit (ASIC), or one or more integrated circuits, and is used to execute relevant programs to implement the technical solutions provided in the embodiments of this specification.

[0076] The memory 1020 can be implemented in the form of ROM (Read Only Memory), RAM (Random Access Memory), static storage device, dynamic storage device, etc. The memory 1020 can store the operating system and other application programs. When the technical solutions provided in the embodiments of this specification are implemented by software or firmware, the relevant program code is stored in the memory 1020 and is called and executed by the processor 1010.

[0077] The input / output interface 1030 is used to connect input / output modules to realize information input and output. The input / output modules can be configured as components in the device (not shown in the figure) or externally connected to the device to provide corresponding functions. Input devices may include keyboards, mice, touch screens, microphones, various sensors, etc., and output devices may include displays, speakers, vibrators, indicator lights, etc.

[0078] The communication interface 1040 is used to connect the communication module (not shown in the figure) to enable communication between this device and other devices. The communication module can communicate via wired means (such as USB, network cable, etc.) or wireless means (such as mobile network, WIFI, Bluetooth, radio (shortwave / ultra-shortwave) communication, satellite communication, data link communication, etc.).

[0079] Bus 1050 includes pathways for transmitting information between various components of the device, such as processor 1010, memory 1020, input / output interface 1030, and communication interface 1040.

[0080] It should be noted that although the above-described device only shows the processor 1010, memory 1020, input / output interface 1030, communication interface 1040, and bus 1050, in specific implementations, the device may also include other components necessary for normal operation. Furthermore, those skilled in the art will understand that the above-described device may only include the components necessary for implementing the embodiments described in this specification, and need not include all the components shown in the figures.

[0081] The electronic devices described above are used to implement the corresponding synchronization methods for power line carrier communication in any of the foregoing embodiments, and have the beneficial effects of the corresponding method implementations, which will not be elaborated here.

[0082] Based on the same inventive concept, corresponding to any of the above-described embodiments, this application also provides a non-transitory computer-readable storage medium storing computer instructions for causing the computer to execute the synchronization method for power line carrier communication as described in any of the above embodiments.

[0083] The computer-readable medium in this embodiment includes permanent and non-permanent, removable and non-removable media, and information storage can be implemented by any method or technology. Information can be computer-readable instructions, data structures, program modules, or other data. Examples of computer storage media include, but are not limited to, phase-change memory (PRAM), static random access memory (SRAM), dynamic random access memory (DRAM), other types of random access memory (RAM), read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), flash memory or other memory technologies, CD-ROM, digital versatile optical disc (DVD) or other optical storage, magnetic tape, magnetic magnetic disk storage or other magnetic storage devices, or any other non-transfer medium that can be used to store information accessible by a computing device.

[0084] The computer instructions stored in the storage medium of the above embodiments are used to cause the computer to execute the synchronization method for power line carrier communication as described in any of the above embodiments, and have the beneficial effects of the corresponding method implementations, which will not be repeated here.

[0085] Those skilled in the art should understand that the discussion of any of the above embodiments is merely exemplary and is not intended to imply that the scope of this application (including the claims) is limited to these examples; this manner of description is merely for clarity, and those skilled in the art should consider the specification as a whole. Within the framework of this application, the above embodiments or the technical features of different embodiments can also be appropriately combined, the steps can be implemented in any order, and there are many other variations of different aspects of the embodiments of this application as described above, which are not provided in the details for the sake of brevity.

[0086] Additionally, to simplify the description and discussion, and to avoid obscuring the embodiments of this application, the well-known power / ground connections to integrated circuit (IC) chips and other components may or may not be shown in the provided drawings. Furthermore, the apparatus may be shown in block diagram form to avoid obscuring the embodiments of this application, and this also takes into account the fact that the details of the implementation of these block diagram apparatuses are highly dependent on the platform on which the embodiments of this application will be implemented (i.e., these details should be entirely within the understanding of those skilled in the art). While specific details (e.g., circuits) are set forth to describe exemplary embodiments of this application, it will be apparent to those skilled in the art that the embodiments of this application can be implemented without these specific details or with variations thereof. Therefore, these descriptions should be considered illustrative rather than restrictive.

[0087] Although this application has been described in conjunction with specific embodiments thereof, many substitutions, modifications, and variations of these embodiments will be apparent to those skilled in the art from the foregoing description. For example, other memory architectures (e.g., dynamic RAM (DRAM)) may use the embodiments discussed.

[0088] The embodiments described herein are intended to cover all such substitutions, modifications, and variations that fall within the broad scope of the appended claims. Therefore, any omissions, modifications, equivalent substitutions, improvements, etc., made without departing from the spirit and principles of the embodiments described herein should be included within the protection scope of this application.

Claims

1. A synchronization method for power line carrier communication, characterized in that, The methods include: Acquire signal data from the transmitter in power line carrier communication, and process the signal data to obtain multiple data frames; A preamble sequence is inserted at the beginning position of a data frame to generate a marked data frame; Obtain the sender's local sequence, perform convolution calculation on the marked data frame and the local sequence, and obtain the convolution value; Determine whether the convolution value exceeds a preset threshold value; if so, determine the position exceeding the threshold value as the peak position. Based on the peak position, a marked data segment is extracted, and autocorrelation calculation is performed on the marked data segment to determine the starting position of the data frame; The receiver is instructed to begin receiving the data frame from the beginning position of each data frame.

2. The synchronization method for power line carrier communication according to claim 1, characterized in that, The step of inserting a preamble sequence at the beginning position of a data frame to generate a marked data frame includes: A preamble sequence is inserted at the beginning of the data frame. The preamble sequence includes two orthogonal frequency division multiplexing symbols. Generate a constant amplitude zero autocorrelation sequence according to the following formula: ； Where c(k) is the constant amplitude zero autocorrelation sequence, N is the length of the constant amplitude zero autocorrelation sequence, k is the discrete index of the constant amplitude zero autocorrelation sequence, and exp(j) is the complex exponential function; The same constant amplitude zero autocorrelation sequence is placed in both of the orthogonal frequency division multiplexing symbols.

3. The synchronization method for power line carrier communication according to claim 2, characterized in that, The convolution calculation on the labeled data frame and the local sequence includes: A search window is set, the length of which is the same as the length of the constant amplitude zero autocorrelation sequence; The search window is slid across the marked data frame multiple times; Perform convolution calculations on the data segments captured by each sliding of the search window and the local sequence; After determining whether the convolution value exceeds a preset threshold, the method further includes: If not, the search window slides again, and the data segment and the local sequence are convolved again to obtain a new convolution value.

4. The synchronization method for power line carrier communication according to claim 3, characterized in that, The convolution calculation on the labeled data frame and the local sequence includes: The convolution calculation is performed according to the following formula: ； ； ； ； Where P(t×N+n) is the normalized cross-correlation value, N is the length of the constant amplitude zero autocorrelation sequence, r(·) is the data segment, c(·) is the local sequence, and c (·) is the conjugate complex number of the constant amplitude zero autocorrelation sequence, t is the number of times the search window slides, R(t×N) is the amplitude of the marked data frame, and W(·) is the cross-correlation value.

5. The synchronization method for power line carrier communication according to claim 2, characterized in that, The convolution calculation on the labeled data frame and the local sequence includes: The data segment is processed using Fourier transform technology to convert it into frequency domain data; The frequency domain data is multiplied by the local sequence to obtain an intermediate value. The intermediate value is then converted into time domain data using the Fourier transform technique, and the time domain data is used as the convolution value.

6. The synchronization method for power line carrier communication according to claim 3, characterized in that, Before determining whether the convolution value exceeds a preset threshold, the following steps are included: If the current data frame has a frame number of 1 in the signal data, then set an initial threshold value; If the frame number of the current data frame in the signal data is greater than 1, then the preset threshold value and the power of the peak value in the previous data frame are obtained. Determine whether the power is between the preset maximum and minimum threshold values; If so, it is determined that the threshold value of the current data frame is the same as the threshold value of the previous data frame; If not, the power of the peak value in the previous data frame is reduced by a preset factor to obtain the threshold value of the current data frame.

7. The synchronization method for power line carrier communication according to claim 2, characterized in that, The step of extracting the marked data segment based on the peak position includes: Two marked data segments are extracted based on the peak position. The position of the first marked data segment is represented as follows: p~p+N; The location of the second marked data segment is represented as follows: p+N f ~p+N+N f ; Where p is the peak position, and N is the length of the constant amplitude zero autocorrelation sequence. f The length of the orthogonal frequency division multiplexing symbol is given.

8. The synchronization method for power line carrier communication according to claim 7, characterized in that, The step of performing autocorrelation calculation on the marked data segment to determine the start position of the data frame includes: The starting position of the data frame is calculated using the following formula: ； ； ； in, N represents the starting position of the data frame. CP Let r be the length of the cyclic prefix, and r(·) be the data segment. (·) represents the conjugate complex number of the data segment, and R(p) represents the amplitude at the peak position. is the preset threshold value, and W(·) is the cross-correlation value.

9. A synchronization system for power line carrier communication, characterized in that, The system includes: The acquisition module is used to acquire signal data from the transmitter in power line carrier communication and process the signal data to obtain multiple data frames. An insertion module is used to insert a preamble sequence at the beginning position of a data frame to generate a marked data frame; The convolution calculation module is used to obtain the sender's local sequence, perform convolution calculation on the marked data frame and the local sequence, and obtain the convolution value; The judgment module is used to determine whether the convolution value exceeds a preset threshold value. If so, the position that exceeds the threshold value is determined as the position of the peak value. The autocorrelation calculation module is used to extract a marked data segment based on the position of the peak value, and perform autocorrelation calculation on the marked data segment to determine the starting position of the data frame; The receiving module enables the receiver to begin receiving the data frame from the beginning position of each data frame.

10. An electronic device, characterized in that, include: Processor and memory; The memory stores a computer program that, when executed by the processor, causes the processor to perform the steps of the synchronization method for power line carrier communication as described in any one of claims 1 to 8.

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