A method and apparatus for identifying a power over Ethernet signal

Abstract

The application discloses a power cat signal identification method and device, and the power cat signal identification method comprises the following steps: sampling data of a set power cat signal frequency band on a power line to obtain sampling data; calculating an equal-interval sliding correlation value sequence of the sampling data and performing energy unitization processing to obtain an energy unitized correlation value sequence; and using a set power cat signal identification criterion to perform signal identification on the energy unitized correlation value sequence to obtain a power cat signal identification result. The application opens up a method path of power cat signal detection in addition to a pilot signal detection path, and has the characteristics of efficient detection, universality and reliability.

Description

Technical Field

[0001] This invention belongs to the field of powerline adapter signal technology, specifically relating to a powerline adapter signal recognition method and device. Background Technology

[0002] On the one hand, the impact of powerline adapter signals on power equipment is highly uncertain; on the other hand, frequent security incidents in recent years have revealed numerous instances of eavesdropping and surveillance signals using powerline adapter modem modules for information transmission, making them extremely difficult to detect under normal circumstances. Therefore, there is an urgent need to detect and identify potential powerline adapter signals in power lines.

[0003] While some powerline adapter signal protocols are publicly available, most are not. Furthermore, although the frequency range of powerline adapter signals is known, the actual signal frequencies are randomly selected within the entire effective frequency band, meaning each frequency could potentially contain a powerline adapter signal. This makes frequency domain detection and identification of powerline adapter signals extremely complex. Especially in non-cooperative modes, powerline adapter signal parameters vary, often resulting in a situation where one pilot signal can only be used with one type of powerline adapter signal, and powerline adapter terminals from different manufacturers are incompatible. Exhaustively enumerating all powerline adapter pilot signals is also impractical; even using a limited number of pilot signals for detection would require massive computation. Therefore, researching efficient, universal, and reliable powerline adapter signal detection methods is of paramount importance. Summary of the Invention

[0004] To address the shortcomings of existing technologies, this invention provides a powerline adapter signal identification method and device, opening up a new method for powerline adapter signal detection besides the pilot signal detection path, and featuring high efficiency, versatility, and reliability.

[0005] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0006] In a first aspect, a method for identifying powerline adapter signals is provided, comprising: sampling data on a set powerline adapter signal frequency band on a power line to obtain sampled data; calculating an equally spaced sliding correlation value sequence on the sampled data and performing energy normalization processing to obtain an energy-normalized correlation value sequence; and using a set powerline adapter signal identification criterion to identify the energy-normalized correlation value sequence to obtain a powerline adapter signal identification result.

[0007] Furthermore, the data sampling includes: sampling the entire powerline adapter signal frequency band using a high sampling rate, or segmenting the entire powerline adapter signal frequency band using a medium sampling rate, wherein there is a set frequency band overlap between two adjacent segments.

[0008] Further, an equally spaced sliding correlation value sequence is calculated from the sampled data, and energy normalization is performed to obtain an energy-normalized correlation value sequence, specifically:

[0009] For sampled data Calculate the equally spaced sliding correlation value sequence This yields the equidistant sliding correlation value sequence corresponding to the three equidistant lengths, i.e., the equidistant sliding correlation value sequence one. Equal-interval sliding correlation value sequence two And the three sequences of equally spaced sliding correlation values ;

[0010] For sampled data Calculate the chip power value of the equally spaced sliding correlation sequence. The chip power values ​​of the equally spaced sliding correlation value sequences corresponding to the three equally spaced lengths are obtained, i.e., chip power value one. Chip power value two And chip power value three ;

[0011] The energy normalization of the equally spaced moving correlation value sequence is performed using the following formula:

[0012]

[0013] in, This is a sequence of correlation values ​​after energy normalization. ;

[0014] This yields the energy-normalized correlation value sequence corresponding to the three equal interval lengths, i.e., the energy-normalized correlation value sequence one. 2. Correlation sequence after energy normalization Correlation sequence three after energy normalization .

[0015] Furthermore, the correlation window length when calculating the equally spaced sliding correlation value sequence. Based on sampling rate Perform the conversion:

[0016]

[0017] in, Indicates rounding down;

[0018] The three equal interval lengths are respectively , and Among them, the effective interval length Based on sampling rate Perform the conversion:

[0019]

[0020] Among them, the function This indicates rounding; while and These are the effective interval lengths The value after deviating from the set ratio, i.e. , .

[0021] Furthermore, the calculation method for the equally spaced sliding correlation value sequences corresponding to the three equally spaced lengths is as follows:

[0022]

[0023]

[0024]

[0025] in, Represents the calculation of conjugate of complex numbers. This indicates taking the modulus of a complex number.

[0026] Furthermore, the chip power values ​​of the equally spaced sliding correlation value sequences corresponding to the three equally spaced lengths are calculated as follows:

[0027]

[0028]

[0029]

[0030] in, This indicates taking the modulus of a complex number.

[0031] Furthermore, the established powerline adapter signal recognition criteria are used to perform signal recognition on the energy-normalized correlation value sequence to obtain the powerline adapter signal recognition result, specifically:

[0032] Determine inequalities or Whether it is true or not; among them, This represents the second sequence of correlation values ​​after energy normalization. The maximum value, This represents the sequence of correlation values ​​after energy normalization. The maximum value, The set threshold;

[0033] If true, then it is determined that there is no powerline cat signal; if false, then the correlation value sequence after energy normalization is calculated. At the set threshold The above number of segments ,judge Check if it is within the valid range; if it is not within the valid range, determine that there is no powerline adapter signal; otherwise, determine that there is a powerline adapter signal.

[0034] Furthermore, after determining that a powerline adapter signal is present, the sampled data is processed. Perform a Fourier transform to convert the sampled data to the frequency domain for analysis, and then analyze the data based on the maximum value and sampling rate. The center frequency and bandwidth of the powerline adapter signal are estimated, thereby obtaining the characteristic parameters of the detected powerline adapter signal.

[0035] Furthermore, the correlation value sequence after energy normalization is calculated. At the set threshold The above number of segments Specifically:

[0036] From the correlation value sequence after energy normalization Iterate from the first point, first setting the initial value. , When encountering a threshold that is higher than or equal to the threshold When the point is set, mark it. When a point below the threshold is encountered, further judgment and marking are performed. Has it already been set to 1? If If the value is 1, then let Thus, the correlation value sequence after energy normalization was detected. At the set threshold The first segment above; at the same time, place again Continue iterating to the next point, and so on;

[0037] The effective range is: .

[0038] In a second aspect, a powerline adapter signal recognition device is provided, comprising a memory, a processor, and a computer program stored in the memory, wherein the processor executes the computer program to implement the steps of the powerline adapter signal recognition method as described in the first aspect.

[0039] Compared with existing technologies, the beneficial effects achieved by this invention are as follows: This invention samples data from a set powerline adapter signal frequency band on power lines; calculates an equally spaced sliding correlation value sequence from the sampled data and performs energy normalization processing to obtain an energy-normalized correlation value sequence; uses a set powerline adapter signal recognition criterion to perform signal recognition on the energy-normalized correlation value sequence to obtain the powerline adapter signal recognition result; and opens up a method path for powerline adapter signal detection other than the pilot signal detection path, which has the characteristics of high efficiency, universality, and reliability. Attached Figure Description

[0040] Figure 1 This is a schematic diagram of the main process of a powerline adapter signal recognition method provided in an embodiment of the present invention;

[0041] Figure 2 This is an example of scanning the entire powerline adapter signal frequency band using a sampling rate of 25MHz in this embodiment of the invention;

[0042] Figure 3 This is a schematic diagram of the equal-interval sliding correlation calculation method in an embodiment of the present invention;

[0043] Figure 4 This is a schematic diagram of the time-domain and frequency-domain waveforms of the interference signal in an embodiment of the present invention, wherein (a) is the time-domain waveform of the periodic interference signal and (b) is the corresponding frequency-domain waveform of the periodic interference signal;

[0044] Figure 5 This is a schematic diagram of equal-interval sliding correlation detection reverse filtering in an embodiment of the present invention, wherein (a) is based on... The correlation value sequence after calculating the equal-interval sliding length and normalizing the energy. There are 7271 segments that exceed the threshold. (b) is based on... The correlation value sequence after calculating and normalizing the energy for the equally spaced sliding length. (c) is based on The correlation value sequence after calculating and normalizing the energy for the equally spaced sliding length. ;

[0045] Figure 6 This is a schematic diagram of the time-domain and frequency-domain waveforms of multiple frames of powerline adapter signals in an embodiment of the present invention, wherein (a) is the time-domain waveform of multiple frames of powerline adapter signals, and (b) is the frequency-domain waveform of the corresponding powerline adapter signal;

[0046] Figure 7 This is a schematic diagram of the equally spaced sliding correlation detection process of multiple frames of powerline adapter signals in an embodiment of the present invention, wherein (a) is the detection process under multiple frames of powerline adapter signals, with The correlation value sequence after calculating and normalizing the energy for the equally spaced sliding length. There are 31 segments above the threshold. (b) shows the majority of powerline adapter signals. The correlation value sequence after calculating and normalizing the energy for the equally spaced sliding length. (c) represents the signal strength of most powerline adapter frames. The correlation value sequence after calculating and normalizing the energy for the equally spaced sliding length. ;

[0047] Figure 8 This is a schematic diagram of the time-domain and frequency-domain waveforms of a few frames of powerline adapter signal in an embodiment of the present invention. (a) is the time-domain waveform of a few frames of powerline adapter signal, and (b) is the frequency-domain waveform of the corresponding powerline adapter signal.

[0048] Figure 9 This is a schematic diagram of the equally spaced sliding correlation detection process for a few frames of powerline adapter signals in an embodiment of the present invention. (a) shows the detection process under a few frames of powerline adapter signals. The correlation value sequence after calculating and normalizing the energy for the equally spaced sliding length. There are 9 segments above the threshold. (b) shows the powerline adapter signal in a few frames. The correlation value sequence after calculating and normalizing the energy for the equally spaced sliding length. (c) shows the signal under a few frames of powerline adapters. The correlation value sequence after calculating and normalizing the energy for the equally spaced sliding length. . Detailed Implementation

[0049] The present invention will be further described below with reference to the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solution of the present invention, and should not be used to limit the scope of protection of the present invention.

[0050] Example 1

[0051] A method for identifying powerline adapter signals includes: sampling data on a set powerline adapter signal frequency band on a power line to obtain sampled data; calculating an equally spaced sliding correlation value sequence on the sampled data and performing energy normalization processing to obtain an energy-normalized correlation value sequence; and using a set powerline adapter signal identification criterion to identify the energy-normalized correlation value sequence to obtain a powerline adapter signal identification result.

[0052] The specific process of the powerline adapter signal recognition method described in this invention is as follows.

[0053] Data is sampled from the powerline signal frequency band to obtain the sampled data.

[0054] Step S1: Monitor the effective frequency band of the entire powerline adapter signal on the power line. You can use a high sampling rate to collect and analyze the entire powerline adapter signal frequency band, or you can use a medium sampling rate to scan the entire powerline adapter signal frequency band in segments. However, there must be at least a certain frequency overlap between each two segments.

[0055] Given that the effective frequency range of powerline adapter signals is 1~86MHz, and assuming the sampling rate of the signal acquisition equipment on the power line is... If the sampling rate is higher than or equal to 85MHz, it is considered to meet the high sampling rate requirement, and the center frequency of the sampling signal is configured as follows: The system samples data for a certain duration, such as 100ms, as a data frame. After the detection module receives the sampled data, it first filters the signal to ensure that the effective bandwidth of the sampled signal is 85MHz, thereby avoiding interference from out-of-band signals. Then, it executes the processing flow in step S3.

[0056] If the sampling rate is less than 85MHz but greater than or equal to 5MHz, it is considered to meet the medium sampling rate requirement. The effective frequency band of the powerline adapter (1~86MHz) can be segmented for scanning, but at least 4MHz of bandwidth overlap is required between two adjacent scanning segments. This ensures that the powerline adapter signal can be detected even at segment boundaries. The 4MHz overlap is determined by the minimum bandwidth of the powerline adapter signal. For each scanning frequency band configuration, a consistent sampling rate, fixed duration, and different sampling center points can be used. For example, 100ms of sampled data at a 25MHz sampling rate can be treated as a single data frame, and then the processing flow in step S3 can be executed.

[0057] If the sampling rate is lower than 5MHz, the powerline adapter signal may be distorted, making it difficult to detect. Therefore, the sampling rate of the module used for powerline adapter signal detection should not be lower than 5MHz.

[0058] Step S2: Let the radio frequency sampling data of one scanning frequency band in the power line be represented as... ,in Its sampling rate is expressed as The center frequency of the corresponding sampled signal is The sampling time for each data set is .

[0059] The sampled data is used to calculate an equally spaced sliding correlation value sequence, and then energy is normalized to obtain an energy-normalized correlation value sequence.

[0060] Step S3: For each group of sampled data Calculate the equally spaced sliding correlation value sequence Each sliding motion requires calculation of three equal interval lengths, resulting in three correlation value sequences: Equal Interval Sliding Correlation Value Sequence 1 Equal-interval sliding correlation value sequence two And the three sequences of equally spaced sliding correlation values The calculation method is as follows:

[0061]

[0062]

[0063]

[0064] in, Represents the calculation of conjugate of complex numbers. This indicates taking the modulus of a complex number.

[0065] For data that meets the sampling rate and frame length conditions, the same powerline adapter signal detection and recognition process can be performed. Only the three interval lengths and related calculation window sizes need to be converted according to different sampling rates. Assume the data frame sampling rate is... Let the effective interval length be . , with an interval of two , interval three Then the calculation yields:

[0066]

[0067] Where 409.5 corresponds to the length of each OFDM symbol of the powerline adapter signal at a sampling rate of 10MHz, which is determined by the characteristics of the powerline adapter itself; function This indicates rounding; while and These are the effective interval lengths The value after deviating from the set ratio, i.e. , .

[0068] Correlation window length when calculating equally spaced sliding correlation value sequences Based on sampling rate Perform the conversion:

[0069]

[0070] in, This indicates rounding down; 70 corresponds to the cyclic prefix length of each OFDM symbol in the powerline adapter signal at a 10MHz sampling rate. Let one frame of original sampled data be... ,in This represents the total length of a frame of sampled data. The equally spaced sliding correlation value sequence is calculated by sliding one sampling point at a time: first from... Initially, take four subsequences respectively. , , , as follows:

[0071]

[0072]

[0073]

[0074]

[0075] Right now , , , They are all long The subsequence, where , , respectively with interval , , Then, the three sets of correlation values ​​were calculated sequentially. , , The calculation formulas are as follows:

[0076]

[0077]

[0078]

[0079] then , , , Each set of data is slid forward one chip to retrieve... Then use the above formula to calculate the three sets of correlation values. , , Similarly, by sliding one chip at a time, three sets of correlation values ​​are calculated, thus obtaining three sets of correlation value sequences. , , ,in To prevent data from going out of bounds.

[0080] Step S4: To facilitate the analysis of the powerline adapter correlation value sequence using absolute thresholds, reduce interference from strong time-domain waveforms, and ensure compatibility with the detection of weak powerline adapter signals, the correlation value sequence calculated in Step S3 needs to be energy-normalized. That is, the correlation value of each correlation value sequence needs to be divided by the chip power of the two correlation value sequences used for calculation. The chip power calculation of the correlation value sequence can be performed simultaneously with the calculation of the correlation value sequence itself. The formula for calculating the chip power of the correlation value sequence is as follows:

[0081] For each set of sampled data Calculate the chip power value of the equally spaced sliding sequence. Different sliding intervals correspond to three different chip power values, i.e., chip power value one... Chip power value two And chip power value three The calculation method is as follows:

[0082]

[0083]

[0084]

[0085] in, This indicates taking the modulus of a complex number.

[0086] Step S5: Perform energy normalization on the three sets of equally spaced sliding correlation value sequences, that is, use the energy normalization of each set of correlation value sequences. , divide the corresponding chip power sequence ,Right now:

[0087]

[0088] in, It is a sequence of correlation values ​​after energy normalization, and satisfies This yields three correlation value sequences after energy normalization, namely, correlation value sequence one after energy normalization. 2. Correlation sequence after energy normalization Correlation sequence three after energy normalization .

[0089] The established powerline adapter signal recognition criteria are used to identify the correlation value sequence after energy normalization to obtain the powerline adapter signal recognition result.

[0090] Step S6: Based on the three sets of energy-normalized correlation value sequences calculated above... , , First, reverse filtering is required. For powerline adapter signals, only two sequences with a sequence interval matching the powerline adapter's OFDM symbol length and a correlation calculation window matching the cyclic prefix length are correlated. Conversely, if the sequence interval does not match the powerline adapter's OFDM symbol length, even if the correlation calculation window size matches the cyclic prefix length, the two sequences will not be correlated. However, for some interference signals, such as single-tone signals, power line frequency signals, and clock signals, which are repetitive signals, because the signal period itself is very short, in… , , They all exhibit correlation under equal sequence intervals. Therefore, periodic interference signals can be filtered out using a reverse filtering method.

[0091] Calculate the last two sets of normalized correlation value sequences, i.e., the second set of correlation value sequences after energy normalization. Correlation sequence three after energy normalization Are their respective maximum values ​​higher than or equal to the threshold value? That is, whether it satisfies or If this condition is met, it indicates that there is no powerline adapter signal, and the sampled signal is a periodic interference signal, meaning the sampled data is within... or If there is correlation between the sequences at equal intervals, it is suspected to be a periodic interference signal, and the process will directly return to step S1 or step S2; otherwise, step S7 will be executed for further judgment.

[0092] Step S7, sampling data, in addition to The sequence needs to be correlated at equal intervals, and the number of segments exceeding the threshold also needs to be within a certain range; otherwise, it cannot be judged as a powerline adapter signal. The range of the number of segments is determined by the minimum and maximum number of frames within a 100ms sampling time.

[0093] Use the same relevant threshold as in step S6. Calculate the first set of correlation values ​​after energy normalization, i.e., the first set of correlation values ​​after energy normalization. Number of segments above the threshold ,judge If the signal is within the valid range, it means there is no powerline signal and the process returns directly. Otherwise, it means the powerline signal was successfully detected and the process continues to step S8, reporting the frequency and bandwidth of the detected powerline signal.

[0094] The correlation value sequence after energy normalization is calculated. At the set threshold The above number of segments Specifically: from Starting from the first point, traverse the first set of energy-normalized correlation value sequences, with initial values ​​set beforehand. ,and If the correlation value at the current point is higher than or equal to the threshold , set mark This indicates that the energy normalization correlation value is above the threshold at this point; if the correlation value at the current point is below the threshold, further judgment of the marker is required first. Has it already been set to 1? If A value of 1 indicates that the segment of the correlation value sequence after energy normalization that is above the threshold ends at this point. Therefore, let... Thus, the correlation value sequence after energy normalization was detected. At the set threshold The first segment above; this also indicates that the energy normalization correlation value is below the threshold at this point, therefore it is set again. ;if A value of 0 indicates that no point with an energy normalization correlation value higher than the threshold was found, so the process continues to the next point for evaluation. This continues until... , The traversal is complete. Finally, the number of segments exceeding the threshold is counted. A judgment will be made if it falls within the valid scope, i.e., it satisfies... If the number of segments exceeding the threshold is within the valid range, it meets the characteristics of continuous frame transmission of the powerline adapter, and the powerline adapter signal is successfully detected. Continue to execute step S8; otherwise, it does not meet the characteristics of continuous frame transmission of the powerline adapter, and the powerline adapter signal is not detected. Return to step S1 or step S2.

[0095] Step S8: After successfully detecting the powerline adapter signal, it is necessary to calculate the center frequency and bandwidth of the powerline adapter signal, and report the scanning frequency range and sampling center frequency at the time of detection.

[0096] Sampling data for the current scan segment ,conduct (Fast Fourier Transform) calculation, converting the signal to the frequency domain for analysis, and then based on the maximum value and sampling rate. Estimate the center frequency and bandwidth of the signal, and report the successful detection of the powerline adapter signal, as well as the characteristic parameters of the powerline adapter signal, such as the scanning frequency range, sampling center frequency, signal center frequency, and signal bandwidth at the time of detection.

[0097] The center frequency of the detected powerline adapter signal is estimated using the following method: find the location of the maximum value in the frequency domain, then use the location of the maximum value as the center and the maximum value minus 10dB as the threshold to calculate the 10-dB bandwidth of the signal; then take the center point of the 10-dB bandwidth as the center frequency of the detected powerline adapter signal.

[0098] Step S9: Return to step S1 and continue scanning the next frequency band.

[0099] Example 2

[0100] like Figures 1-9 As shown, based on the powerline adapter signal recognition method described in Embodiment 1, the specific application process of the powerline adapter signal recognition method in this embodiment is further explained as follows.

[0101] Although the frequency range of the powerline adapter signal is fixed, the center frequency of the signal is not fixed and is random during each actual communication. This requires the powerline adapter signal detection to support full scanning of the effective frequency range. Figure 2 As shown, the frequency range of the powerline adapter signal in the powerline environment is known to be 1~86MHz. Assuming the sampling rate of the signal acquisition device is 25MHz, the 1~86MHz powerline adapter signal control frequency band is divided into four segments for segmented scanning, as shown in Table 1.

[0102] Table 1: Frequency Band Allocation Results for Powerline Adapters

[0103]

[0104] The four sampling center frequencies mentioned above will be configured sequentially, using a sampling rate of 25MHz. The powerline adapter frequency band from 1 to 86MHz will be periodically scanned in segments, with a sampling duration of approximately 100ms for each band. Since the actual frequency of the powerline adapter signal is random, the sampled data in each segment may contain a powerline adapter signal. Therefore, the same detection and identification processing will be performed on each frame of sampled data.

[0105] Sampling rate of the signal to be detected The OFDM symbol length of the powerline adapter signal can be calculated using the formula. The interval length values ​​for the other two reverse filters are... , The relevant calculation window size was calculated as follows. .

[0106] Let the original sampling data be ,like Figure 3 As shown, starting from the first sampling point, 176 consecutive sampling points are taken as a subsequence. ; then interval After sampling one point, take 176 consecutive sampling points as a subsequence. Similarly, starting from the first sampling point, the interval is... After sampling one point, take 176 consecutive sampling points as a subsequence. Then, starting from the first sampling point, at intervals... After sampling one point, take 176 consecutive sampling points as a subsequence. .

[0107] subsequence , , Calculate the sum and subsequences separately The relevant value is calculated using the following formula: , , In the formula Represents the calculation of conjugate of complex numbers. This indicates modulo operation on a complex number, or absolute value calculation. The result is obtained from this calculation. Three related values ​​at time , , .

[0108] Then slide the sampled data forward by one chip, that is, starting from the second sample point, take 176 consecutive sample points as a subsequence. ; then interval After sampling one point, take 176 consecutive sampling points as a subsequence. Similarly, starting from the first sampling point, the interval is... After sampling one point, take 176 consecutive sampling points as a subsequence. Then, starting from the first sampling point, at intervals... After sampling one point, take 176 consecutive sampling points as a subsequence. The calculation is performed using the formula in step S3. Three related values ​​at time , , Then, by analogy, three sets of equally spaced sliding correlation value sequences are finally calculated. , , ,in .

[0109] Next, the three sets of correlation value sequences were analyzed. , , Energy normalization processing. That is, while calculating the equally spaced sliding correlation value, the square root of the product of the power of two equally spaced sub-sequence chips can also be calculated simultaneously, as shown in the formula: , , .

[0110] Divide the corresponding bits of the correlation value sequence and the chip power sequence to achieve energy normalization. The corresponding calculation formula is: After energy normalization of the correlation value sequence, all correlation values ​​fall between 0 and 1, i.e. Let the three sets of correlation value sequences after energy normalization be denoted as follows: , , .

[0111] First use the correlation value sequences of the last two sets of energy normalized values. , Perform reverse filtering. For example... Figure 5 , Figure 7 , Figure 9 As shown, define the relevant value threshold. , Figure 5 The maximum values ​​of the last two sequences both exceeded the threshold, so they did not meet the powerline adapter signal conditions and were therefore filtered out. Figure 7 and Figure 9 The maximum values ​​of the last two sequences are both below the threshold, so they are retained for further evaluation.

[0112] After reverse filtering, what remains? Figure 7 and Figure 9 Data that meets the conditions, and then the correlation value sequence after energy normalization of the first group for each. Perform the test. Still use the relevant threshold values. Define initial values , Then iterate through For all points, if the correlation value of the current point is higher than or equal to the threshold. When, set a mark This indicates that the energy normalization correlation value is above the threshold at this point; if the correlation value at the current point is below the threshold, further judgment of the marker is required first. Has it already been set to 1? If A value of 1 indicates that the segment of the correlation value sequence after energy normalization that is above the threshold ends. This also indicates that the energy normalization correlation value is below the threshold at this point, therefore it is set again. ;if A value of 0 indicates that no point with an energy normalization correlation value higher than the threshold was found, and the process continues to the next point for evaluation. This continues until... , The traversal is complete. Finally, the number of segments exceeding the threshold is counted. To make a judgment, such as Figure 7 The number of segments above the relevant threshold The signal was successfully detected as it was within the valid range. If the number of segments in group 9 exceeds the relevant threshold... Similarly, within the effective range, the powerline adapter signal was successfully detected.

[0113] For sampling data that successfully detected the powerline adapter signal The signal frequency and 10-dB bandwidth are further estimated, and then reported along with the frequency band range of the currently collected data, the sampling center frequency, and the successful detection marker. This completes the data processing flow for one scan segment, and then the powerline adapter signal is detected and identified from the sampled data of the next scan segment.

[0114] Example 3

[0115] Based on the powerline adapter signal recognition method described in Embodiments 1 and 2, this embodiment provides a powerline adapter signal recognition device, including a memory, a processor, and a computer program stored in the memory. The device is characterized in that the processor executes the computer program to implement the steps of the powerline adapter signal recognition method as described in Embodiment 1.

[0116] Those skilled in the art will understand that embodiments of this application can be provided as methods, systems, or computer program products. Therefore, this application can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, this application can take the form of a computer program product embodied on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0117] This application is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of this application. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart... Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0118] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0119] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0120] The embodiments of the present invention have been described above with reference to the accompanying drawings. However, the present invention is not limited to the specific embodiments described above. The specific embodiments described above are merely illustrative and not restrictive. Those skilled in the art can make many other forms under the guidance of the present invention without departing from the spirit and scope of the claims. All of these forms are within the protection scope of the present invention.

Claims

1. A method for identifying powerline adapter signals, characterized in that, include: Data is sampled from the powerline signal frequency band to obtain the sampled data. The sampled data is used to calculate an equally spaced sliding correlation value sequence, and then energy is normalized to obtain an energy-normalized correlation value sequence. The established powerline adapter signal recognition criteria are used to identify the correlation value sequence after energy normalization to obtain the powerline adapter signal recognition result.

2. The powerline adapter signal recognition method according to claim 1, characterized in that, The data sampling includes: sampling the entire powerline adapter signal frequency band using a high sampling rate, or scanning the entire powerline adapter signal frequency band in segments using a medium sampling rate, wherein there is a set frequency band overlap between two adjacent segments.

3. The powerline adapter signal recognition method according to claim 1, characterized in that, The sampled data is used to calculate an equally spaced sliding correlation value sequence, and then energy-normalized to obtain an energy-normalized correlation value sequence, specifically: For sampled data Calculate the equally spaced sliding correlation value sequence This yields the equidistant sliding correlation value sequence corresponding to the three equidistant lengths, i.e., the equidistant sliding correlation value sequence one. Equal-interval sliding correlation value sequence two And the three sequences of equally spaced sliding correlation values ; For sampled data Calculate the chip power value of the equally spaced sliding correlation sequence. The chip power values ​​of the equally spaced sliding correlation value sequences corresponding to the three equally spaced lengths are obtained, i.e., chip power value one. Chip power value two And chip power value three ; The energy normalization of the equally spaced moving correlation value sequence is performed using the following formula: in, This is a sequence of correlation values ​​after energy normalization. ; This yields the energy-normalized correlation value sequence corresponding to the three equal interval lengths, i.e., the energy-normalized correlation value sequence one.

2. Correlation sequence after energy normalization Correlation sequence three after energy normalization .

4. The powerline adapter signal recognition method according to claim 3, characterized in that, Correlation window length when calculating equally spaced sliding correlation value sequences Based on sampling rate Perform the conversion: in, Indicates rounding down; The three equal interval lengths are respectively , and Among them, the effective interval length Based on sampling rate Perform the conversion: Among them, the function This indicates rounding; while and These are the effective interval lengths The value after deviating from the set ratio, i.e. , .

5. The powerline adapter signal recognition method according to claim 4, characterized in that, The calculation method for the equidistant sliding correlation value sequences corresponding to the three equidistant lengths is as follows: in, Represents the calculation of conjugate of complex numbers. This indicates taking the modulus of a complex number.

6. The powerline adapter signal recognition method according to claim 4, characterized in that, The chip power values ​​of the equally spaced sliding correlation value sequences corresponding to the three equally spaced lengths are calculated as follows: in, This indicates taking the modulus of a complex number.

7. The powerline adapter signal recognition method according to claim 3, characterized in that, The powerline adapter signal recognition results are obtained by using the established powerline adapter signal recognition criteria to identify the correlation value sequence after energy normalization. Determine inequalities or Whether it is true or not; among them, This represents the second sequence of correlation values ​​after energy normalization. The maximum value, This represents the sequence of correlation values ​​after energy normalization. The maximum value, The set threshold; If true, then it is determined that there is no powerline cat signal; if false, then the correlation value sequence after energy normalization is calculated. At the set threshold The above number of segments ,judge Check if it is within the valid range; if it is not within the valid range, determine that there is no powerline adapter signal; otherwise, determine that there is a powerline adapter signal.

8. The powerline adapter signal recognition method according to claim 7, characterized in that, After determining that a powerline adapter signal is present, the sampled data is processed. Perform a Fourier transform to convert the sampled data to the frequency domain for analysis, and then analyze the data based on the maximum value and sampling rate. The center frequency and bandwidth of the powerline adapter signal are estimated, thereby obtaining the characteristic parameters of the detected powerline adapter signal.

9. The powerline adapter signal recognition method according to claim 7, characterized in that, Calculate the correlation sequence after energy normalization. At the set threshold The above number of segments Specifically: From the correlation value sequence after energy normalization Iterate from the first point, first setting the initial value. , When encountering a threshold that is higher than or equal to the threshold When the point is set, mark it. ; When a point below the threshold is encountered, further judgment and marking are performed. Has it already been set to 1? If If the value is 1, then let Thus, the correlation value sequence after energy normalization was detected. At the set threshold The first segment above; at the same time, place again Continue iterating to the next point, and so on; The effective range is .

10. A powerline adapter signal recognition device, comprising a memory, a processor, and a computer program stored in the memory, characterized in that, The processor executes the computer program to implement the steps of the powerline adapter signal recognition method as described in any one of claims 1 to 9.

Images