Signal detection apparatus, method, receiver and chip

Abstract

The application discloses a signal detection device, method, receiver and chip, and relates to the technical field of communication. The device comprises: a demodulation and symbol decision module, which is used for grouping a target digital signal to obtain a plurality of symbols, and performing coherent demodulation and symbol decision on the symbols; a code word correlation and detection module, which is used for performing correlation and correlation peak detection on the symbol decision results in a symbol unit; a link measurement module, which is used for obtaining instruction time slot power according to symbol power and correlation peak detection results in a symbol unit; and a code word decision and confirmation module, which is used for performing code word decision and co-frequency interference determination in a symbol unit, and obtaining a target instruction according to the co-frequency interference determination results and the code word decision results. The device groups signals by using the spread spectrum characteristics and periodic characteristics of code word sequences, and performs symbol decision and code word decision in a group unit. Unreliable decision results are excluded through interference detection, and low-complexity and high-reliability signal detection is realized.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of communication, and particularly relates to a signal detection device and method, a receiver and a chip. BACKGROUND

[0002] For a signal using FSK (Frequency-Shift Keying) modulation based on Barker code spreading (namely, SFSK (Spread Frequency Shift Keying) modulation mode), such as a fast shutdown signal of a photovoltaic shutdown device, its detection generally includes two steps of symbol demodulation and instruction recognition. The symbol demodulation needs to demodulate the FSK signal; the instruction recognition is based on a sufficient symbol sequence that has been determined, and is correlated with different instruction sequences stored locally, and when the correlation value exceeds a threshold, it is considered that the corresponding instruction is recognized.

[0003] At present, the focus of signal detection technology is the demodulation of FSK signals. For symbol level demodulation, mainly coherent demodulation method, envelope detection method, zero-crossing detection method and FFT spectrum analysis method are adopted, and path optimization strategy and decision threshold automatic updating strategy are supplemented to improve the reliability of FSK demodulation. However, these methods have certain limitations, for example, the good autocorrelation characteristics of code words in the signal and the periodic characteristics between code words are not fully utilized, resulting in that these methods cannot achieve good anti-interference performance with small implementation complexity.

[0004] CONTENT

[0005] The present application aims to at least solve one of the technical problems in the related art. To this end, the purpose of the present application is to propose a signal detection device and method, a receiver and a chip to realize low-complexity and high-reliability signal detection.

[0006] In a first aspect, the application provides a signal detection device, comprising: a demodulation and symbol decision module, configured to group a target digital signal to obtain a plurality of symbols, to perform coherent demodulation and symbol decision on the plurality of symbols respectively, and to obtain M-path metric values, S-path metric values, symbol powers, M-path symbol decision results and S-path symbol decision results of each of the symbols; an M-path code word correlation and detection module, configured to correlate code word reference sequences with the M-path symbol decision results of the plurality of symbols respectively, and to perform correlation peak detection on each of the correlation results respectively to obtain M-path peak value information of each of the symbols; an S-path code word correlation and detection module, configured to correlate code word reference sequences with the S-path symbol decision results of the plurality of symbols respectively, and to perform correlation peak detection on each of the correlation results respectively to obtain S-path peak value information of each of the symbols; a link measurement module, configured to obtain M-path instruction time slot powers of each of the symbols according to symbol powers and M-path peak value counts in M-path peak value information of each of the symbols, and to obtain S-path instruction time slot powers of each of the symbols according to symbol powers and S-path peak value counts in S-path peak value information of each of the symbols; and a code word decision and confirmation module, configured to perform code word decision according to M-path peak value information and S-path peak value information of each of the symbols to obtain M-path code word decision results and S-path code word decision results, to perform same-frequency interference judgment on M-path and S-path according to M-path metric values, S-path metric values, symbol powers, M-path instruction time slot powers and S-path instruction time slot powers of each of the symbols, and to obtain a target instruction according to same-frequency interference judgment results, M-path code word decision results and S-path code word decision results of each of the symbols.

[0007] In a second aspect, the application provides a receiver comprising the signal detection device of the first aspect.

[0008] In a third aspect, the present application provides a signal detection method, comprising: grouping a target digital signal to obtain a plurality of symbols, respectively performing coherent demodulation and symbol decision on the plurality of symbols to obtain M-path metric values, S-path metric values, symbol powers, M-path symbol decision results and S-path symbol decision results of each of the symbols; respectively correlating a code word reference sequence with the M-path symbol decision results of the plurality of symbols, and respectively performing correlation peak detection on the correlation results to obtain M-path peak value information of each of the symbols, and respectively correlating the code word reference sequence with the S-path symbol decision results of the plurality of symbols, and respectively performing correlation peak detection on the correlation results to obtain S-path peak value information of each of the symbols; obtaining M-path instruction time slot powers of each of the symbols according to the symbol powers and M-path peak value counts in the M-path peak value information of each of the symbols, and obtaining S-path instruction time slot powers of each of the symbols according to the symbol powers and S-path peak value counts in the S-path peak value information of each of the symbols; performing code word decision according to the M-path peak value information and the S-path peak value information of each of the symbols to obtain M-path code word decision results and S-path code word decision results, performing co-frequency interference judgment on the M-path and the S-path according to the M-path metric values, the S-path metric values, the symbol powers, the M-path instruction time slot powers and the S-path instruction time slot powers of each of the symbols, and obtaining a target instruction according to the co-frequency interference judgment results, the M-path code word decision results and the S-path code word decision results of each of the symbols.

[0009] In a fourth aspect, the present application provides a chip, comprising a memory, a processor and a computer program stored in the memory, wherein the computer program is executed by the processor to implement the signal detection method of the third aspect.

[0010] The signal detection device, method, receiver and chip of the embodiments of the present application first group a target digital signal to obtain a plurality of symbols, then perform coherent demodulation and symbol decision in units of symbols, perform correlation and correlation peak detection on the symbol decision results in units of symbols, obtain instruction time slot powers in units of symbols according to the symbol powers and the correlation peak detection results, perform code word decision and co-frequency interference judgment in units of symbols, and obtain a target instruction according to the co-frequency interference judgment results and the code word decision results. Thus, the signal is grouped by using the spreading characteristics and periodic characteristics of the code word sequence, and the symbol decision and the code word decision are performed in units of groups, the unreliable decision results are excluded through interference detection, and the signal detection with low complexity and high reliability is realized.

[0011] Additional aspects and advantages of the present application will be made apparent by the following description. BRIEF DESCRIPTION OF DRAWINGS

[0012] Figure 1 is a structure schematic diagram of a fast-off communication frame;

[0013] Figure 2(a) is a diagram of in-band interference level;

[0014] Figure 2(b) is a diagram of out-of-band interference level;

[0015] Figure 3 Figure 3 is a structure diagram of a signal detection device according to an embodiment of the present application;

[0016] Figure 4 Figure 4 is a structure diagram of a demodulation and symbol decision module according to an embodiment of the present application;

[0017] Figure 5 Figure 5 is a structure diagram of a demodulation and symbol decision module according to another embodiment of the present application;

[0018] Figure 6 Figure 6 is a structure diagram of a demodulation and symbol decision module according to yet another embodiment of the present application;

[0019] Figure 7 Figure 7 is a structure diagram of an M-path code word correlation and detection module according to an embodiment of the present application;

[0020] Figure 8 Figure 8 is a structure diagram of an S-path code word correlation and detection module according to an embodiment of the present application;

[0021] Figure 9 Figure 9 is a flow chart of code word correlation peak detection according to an embodiment of the present application;

[0022] Figure 10 Figure 10 is a work flow chart of a link measurement module according to an embodiment of the present application;

[0023] Figure 11 Figure 11 is a structure diagram of a code word decision and determination module according to an embodiment of the present application;

[0024] Figure 12 Figure 12 is a work flow chart of a code word decision and determination module according to an embodiment of the present application;

[0025] Figure 13 Figure 13 is a structure diagram of a signal detection device according to another embodiment of the present application;

[0026] Figure 14 Figure 14 is a structure diagram of an analog front-end processing module according to an embodiment of the present application;

[0027] Figure 15 Figure 15 is a structure diagram of an analog front-end processing module according to another embodiment of the present application;

[0028] Figure 16 Figure 16 is a structure diagram of a signal detection device according to yet another embodiment of the present application;

[0029] Figure 17 This is a structural block diagram of the receiver according to an embodiment of this application;

[0030] Figure 18 This is a flowchart of a signal detection method according to an embodiment of this application;

[0031] Figure 19 This is a structural block diagram of the chip according to an embodiment of this application. Detailed Implementation

[0032] The embodiments of this application are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain this application, and should not be construed as limiting this application.

[0033] In the field of communication technology, the accuracy of signal detection ensures the security and reliability of communication. For example, in a photovoltaic system, when maintenance is required on the photovoltaic modules, a fast shutdown signal is sent from a transmitter installed on the inverter to a receiver in the photovoltaic module's shutdown circuit breaker to control the rapid shutdown of the circuit breaker. If the receiver cannot accurately detect this fast shutdown signal, it will be unable to quickly shut down the circuit breaker installed on the photovoltaic module, potentially leading to a dangerous DC high-voltage situation.

[0034] To achieve accurate signal detection, it is necessary to understand the structure of the signal to be detected. Taking the aforementioned fast shutdown signal as an example, the SunSpec Consortium (a standardization organization focused on solar and energy storage technologies) defines the communication specifications for shutdown ("OFF") and turn-on ("ON") commands between inverters and photovoltaic modules based on power line carrier communication (PLC). The transmitter and receiver communicate via power lines, using SFSK modulation to send carrier signals. Different symbols can be represented by two different frequencies: Fm = 131.25kHz and Fs = 143.75kHz. Different combinations of symbols form different codewords, and different combinations of codewords form different commands. Each symbol is a 5.12ms Fm or Fs frequency signal, each codeword contains 11 symbols corresponding to an 11-length Barker code, and each command contains 3 codewords. Figure 1As shown, each communication frame (209 symbol periods, 1070.08 ms) contains an instruction time slot (33 symbol periods, 168.96 ms) and a silent time slot (176 symbol periods, 901.12 ms). Whether the receiver can correctly detect the two different frequency symbols and detect the code word according to the symbol sequence and combine the "ON" or "OFF" instruction is the key to realize the rapid shutdown. When the receiver continuously detects the "ON" instruction, the shutdown needs to keep open to let the photovoltaic module generate electricity; when the receiver continuously detects no "ON" instruction or detects the "OFF" instruction, the shutdown needs to be closed to cut off the output of the photovoltaic module.

[0035] In actual use scenarios, the signal of the rapid shutdown based on the SunSpec protocol is greatly affected by interference, which is easy to cause mis-detection and affect the reliability of communication, resulting in mis-shutdown or failure to shutdown. In order to avoid such problems, the SunSpec alliance specifies in "SunSpec Communication Signal for Rapid Shutdown Test Specification, APPROVED 19" the test requirements for the receiver, and clearly specifies that the receiver should be able to correctly detect the "ON" and "OFF" instructions under the interference of the specified frequency and power single-tone signal. The specified interference frequencies include out-of-band interference, in-band interference and same-frequency interference, and the interference power is 0 dB to 50 dB higher than the signal power according to different interference frequencies, which puts high requirements on the SunSpec receiver access. Figures 2(a) and 2(b) respectively show the requirements for in-band and out-of-band interference.

[0036] In order to realize accurate detection of the signal, the present application proposes a signal detection device, which uses a low-complexity symbol decision algorithm for symbol decision, combines the spread spectrum characteristics and periodic characteristics of the code word sequence for code word decision, and excludes unreliable decision results through interference detection, so as to realize high-reliability signal detection with low complexity. Meanwhile, the present application also proposes a signal detection method, a receiver and a chip.

[0037] The signal detection device, method, receiver and chip of the embodiments of the present application are described below with reference to the accompanying drawings.

[0038] Figure 3 Figure 1 is a structural block diagram of the signal detection device of one embodiment of the present application.

[0039] As shown in Figure 1, the signal detection device 100 includes a demodulation and symbol decision module 10, an M-way code word correlation and detection module 20, an S-way code word correlation and detection module 30, a link measurement module 40 and a code word decision and confirmation module 50. Figure 3 As shown, the signal detection device 100 includes a demodulation and symbol decision module 10, an M-way code word correlation and detection module 20, an S-way code word correlation and detection module 30, a link measurement module 40 and a code word decision and confirmation module 50.

[0040] The demodulation and symbol decision module 10 is configured to group the target digital signal to obtain a plurality of symbols, and perform coherent demodulation and symbol decision on the plurality of symbols respectively to obtain M-path metric values, S-path metric values, symbol powers, M-path symbol decision results and S-path symbol decision results of each symbol. The M-path code word correlation and detection module 20 is configured to correlate the code word reference sequence with the M-path symbol decision results of the plurality of symbols respectively, and perform correlation peak detection on each correlation result respectively to obtain M-path peak value information of each symbol. The S-path code word correlation and detection module 30 is configured to correlate the code word reference sequence with the S-path symbol decision results of the plurality of symbols respectively, and perform correlation peak detection on each correlation result respectively to obtain S-path peak value information of each symbol. The link measurement module 40 is configured to obtain M-path instruction time slot powers of each symbol according to the symbol powers and M-path peak value counts in the M-path peak value information of each symbol, and obtain S-path instruction time slot powers of each symbol according to the symbol powers and S-path peak value counts in the S-path peak value information of each symbol. The code word decision and confirmation module 50 is configured to perform code word decision according to the M-path peak value information and the S-path peak value information of each symbol respectively to obtain M-path code word decision results and S-path code word decision results, perform co-frequency interference judgment on the M path and the S path according to the M-path metric values, the S-path metric values, the symbol powers, the M-path instruction time slot powers and the S-path instruction time slot powers of each symbol, and obtain the target instruction according to the co-frequency interference judgment results, the M-path code word decision results and the S-path code word decision results of each symbol.

[0041] Specifically, the target digital signal can be an analog-to-digital converted signal of a to-be-detected signal (such as a fast shutdown signal for a photovoltaic module), which contains a plurality of code words (such as 3 code words), each code word includes a plurality of symbols (such as 11 symbols), and each symbol includes a plurality of sampling points. The demodulation and symbol decision module 10 can process the target digital signal X(j) sampling point by sampling point, such as grouping the target digital signal according to one symbol per Lsym sampling points to obtain k symbols Y(k, l), where Lsym can be an integer that is an integer multiple of the symbol period length, so that each symbol can be divided into a plurality of symbols by grouping, j is a global index of the sampling point, k is an index of the symbol where the sampling point is located, and l is an index of the sampling point within the symbol, and the relationship among the three is: j = (k-1)*Lsym+l; then coherent demodulation and symbol decision are performed on the symbols to obtain M-path metric values, S-path metric values, symbol powers, M-path symbol decision results and S-path symbol decision results of each symbol. Compared with directly performing coherent demodulation and symbol decision on the target digital signal, the present application first groups the target digital signal, and then performs coherent demodulation and symbol decision on the symbols, which can reduce the complexity of processing.

[0042] After obtaining the M-path symbol decision result and the S-path symbol decision result, the M-path code word correlation and detection module 20 and the S-path code word correlation and detection module 30 respectively perform correlation according to the code word reference sequence (such as +1, -1 sequence, which can be generated according to requirements, signal protocol requirements, etc.) and the M-path symbol decision result and the S-path symbol decision result of multiple symbols in a symbol unit, and perform correlation peak detection on the correlation results to obtain the M-path peak value information and the S-path peak value information of each symbol. Then, the link measurement module 40 obtains the M-path instruction time slot power of the symbol according to the symbol power and the M-path peak value count in the M-path peak value information, and obtains the S-path instruction time slot power of the symbol according to the symbol power and the S-path peak value count in the S-path peak value information in a symbol unit. The code word decision and confirmation module 50 performs code word decision according to the M-path peak value information and the S-path peak value information in a symbol unit to obtain the M-path code word decision result and the S-path code word decision result, and performs co-frequency interference determination on the M-path and the S-path according to the M-path metric value, the S-path metric value, the symbol power, the M-path instruction time slot power and the S-path instruction time slot power of each symbol, and obtains the target instruction according to the co-frequency interference determination result, the M-path code word decision result and the S-path code word decision result of each symbol. In this way, code word decision is realized by using the spreading characteristics and periodic characteristics of the code word sequence, and unreliable decision results are excluded through interference detection, so that high-reliability signal detection can be realized with lower complexity; and symbol and code word decision are independently performed on the two frequency paths of the signal, which can reduce the implementation complexity; at the same time, real-time metric value and power information can be used for symbol decision and further code word decision, so that complex historical information does not need to be maintained, and the periodic timing of the entire communication frame does not need to be maintained, which reduces the implementation difficulty.

[0043] In some embodiments of the present application, as shown in Figure 4 The demodulation and symbol decision module 10 includes a grouping unit 11, an M-path waveform correlation unit 12, an S-path waveform correlation unit 13, an average power unit 14, an M-path symbol decision unit 15 and an S-path symbol decision unit 16. The grouping unit 11 is configured to allocate symbols to points in the target digital signal, and allocate one symbol to every preset number of points to obtain multiple symbols. The M-path waveform correlation unit 12 is configured to coherently demodulate the M-path waveform in each symbol to obtain the M-path metric value of each symbol. The S-path waveform correlation unit 13 is configured to coherently demodulate the S-path waveform in each symbol to obtain the S-path metric value of each symbol. The average power unit 14 is configured to solve the average power of each symbol to obtain the symbol power of each symbol. The M-path symbol decision unit 15 is configured to obtain the M-path symbol decision result of each symbol according to the M-path metric value and the symbol power of each symbol. The S-path symbol decision unit 16 is configured to obtain the S-path symbol decision result of each symbol according to the S-path metric value and the symbol power of each symbol.

[0044] Specifically, referring toFigure 4 In order to facilitate coherent demodulation and decision, the grouping unit 11 assigns a symbol to each point in the target digital signal X(j) and assigns a symbol to every Lsym (i.e. a preset value) sampling points to obtain Y(k, l), i.e. each symbol is divided into Nsym equal length symbols, each symbol length Lsym = Lbit / Nsym, where Lbit is the length of each symbol period, and Nsym can be an integer of 3-32, such as Nsym can be 4 or 8. Then, coherent demodulation and symbol decision are performed in symbol units to obtain M-path metric values Cm(k), S-path metric values Cs(k), symbol power P(k) and M-path symbol decision results Bm(k) and S-path symbol decision results Bs(k), wherein Bm(k) is output to the M-path code word correlation and detection module 20, Bs(k) is output to the S-path code word correlation and detection module 30, and Cm(k), Cs(k) and P(k) are output to the link measurement module 40. Wherein, j is a global index of the sampling points, k is an index of the symbol in which the sampling points are located, and l is an index of the sampling points within the symbol, and the relationship among the three is: j = (k-1)*Lsym+l.

[0045] The grouped signal Y(k, l) is multiplied by a complex signal with a frequency Fm at the point, and the sum of the multiplication results is calculated in symbol units and modulated to obtain the M-path metric value of each symbol, which is calculated as shown in formula (1):

[0046]

[0047] Wherein, Cm(k) represents the M-path metric value of the kth symbol, e 2πi*Fm*l*Ts represents a complex signal with a frequency Fm, i represents an imaginary unit, Ts represents a sampling period, and Y(k, l) represents the signal of the lth sampling point of the kth symbol.

[0048] The grouped signal Y(k, l) is multiplied by a complex signal with a frequency Fs at the point, and the sum of the multiplication results is calculated in symbol units and modulated to obtain the S-path metric value of each symbol, which is calculated as shown in formula (2):

[0049]

[0050] Wherein, Cs(k) represents the S-path metric value of the kth symbol.

[0051] The power sum of the grouped signal Y(k, l) in each symbol is calculated in symbol units to obtain the symbol power, which is calculated as shown in formula (3):

[0052]

[0053] Wherein, P(k) represents the symbol power of the kth symbol.

[0054] For each symbol, M-way symbol validity determination is performed using its M-way metric value Cm(k), symbol power P(k), and bit decision threshold bitThr to obtain the symbol decision result Bm(k). The decision method is shown in formula (4):

[0055]

[0056] For each symbol, the S-way symbol validity is determined using its S-way metric Cs(k), symbol power P(k), and bit decision threshold bitThr, resulting in the symbol decision result Bs(k). The decision method is shown in formula (5).

[0057]

[0058] Therefore, by converting sampling points to symbols and performing waveform correlation and symbol decision on a symbol-by-symbol basis, outputting a set of results for each symbol, the good autocorrelation characteristics of codewords in the signal and the periodic characteristics between codewords are utilized, reducing the complexity of signal detection. Furthermore, by using two frequency paths for validity decision-making instead of directly determining which frequency the symbol is currently transmitting, combined with the subsequent false alarm removal processing of the codeword decision algorithm, a certain false alarm probability can be allowed in the symbol validity decision. This places lower requirements on the bit decision threshold, allowing the same bit decision threshold to be conveniently applied to different interference scenarios, thus reducing implementation complexity.

[0059] In some embodiments of this application, such as Figure 5 As shown, the demodulation and symbol decision module 10 further includes a dual-frequency filtering unit 17. The dual-frequency filtering unit 17 is connected before the grouping unit 11 and is used to perform dual-frequency filtering on the target digital signal, and then transmit the filtered signal to the grouping unit 11.

[0060] In this embodiment, the demodulation and symbol decision module 10 processes the input target digital signal sample by sample and outputs the processing result in units of symbols; that is, this module performs a conversion from sample points to symbols. See also Figure 5 The dual-frequency filtering unit 17 performs dual-frequency filtering on the target digital signal X(j) to obtain Y(j), assigns symbols to the points in Y(j), and assigns one symbol to each Lsym point to obtain Y(k,l). Then, coherent demodulation and symbol decision are performed on a symbol-by-symbol basis to obtain M-channel metric values ​​Cm(k), S-channel metric values ​​Cs(k), symbol power P(k), and M-channel symbol decision results Bm(k) and S-channel symbol decision results Bs(k).

[0061] Compared to Figure 4 The embodiment shown, Figure 5The illustrated embodiment adds dual-frequency selective filtering, that is, after dual-frequency selective filtering of the target digital signal X(j), Y(j) is obtained, which can filter out in-band interference; and, Y(j) is grouped. Specifically, the dual-frequency selective filtering unit 17 contains two passbands, the center frequencies of which are Fm and Fs, respectively, used to filter out in-band interference while retaining the Fm and Fs signals. Compared to Figure 5 The embodiment shown, Figure 4 The illustrated embodiment simplifies the computation and reduces the implementation complexity.

[0062] In some embodiments of this application, such as Figure 6 As shown, the grouping unit 11 includes a first grouping subunit 111 and a second grouping subunit 112; the demodulation and symbol decision module 10 further includes: an M-channel frequency selective filtering unit 171, an S-channel frequency selective filtering unit 172, and a summing unit 173. The M-channel frequency selective filtering unit 171 performs M-channel frequency selective filtering on the target digital signal. The first grouping subunit 111 assigns symbols to points in the M-channel frequency selective filtered signal, with one symbol assigned to every preset value of points. The S-channel frequency selective filtering unit 172 performs S-channel frequency selective filtering on the target digital signal. The second grouping subunit 112 assigns symbols to points in the S-channel frequency selective filtered signal, with one symbol assigned to every preset value of points. The summing unit 173 is connected to the first grouping subunit 111, the second grouping subunit 112, and the average power unit 14, respectively, and sums the grouping results of the M-channel frequency selective filtered signal and the S-channel frequency selective filtered signal, outputting the summation result to the average power unit 14.

[0063] Specifically, see Figure 6 The M-channel frequency selective filtering unit 171 performs M-channel frequency selective filtering on X(j) to obtain Ym(j). The first grouping subunit 111 assigns symbols to the points in Ym(j), and assigns one symbol to each Lsym point to obtain Ym(k,l). The S-channel frequency selective filtering unit 172 performs S-channel frequency selective filtering on Y(j) to obtain Ys(j). The second grouping subunit 112 assigns symbols to the points in Ys(j), and assigns one symbol to each Lsym point to obtain Ys(k,l). The summing unit 173 adds Ym(k,l) and Ys(k,l) to obtain Y(k,l). Then, coherent demodulation and symbol decision are performed on a symbol-by-symbol basis to obtain the M-channel metric Cm(k), the S-channel metric Cs(k), the symbol power P(k), and the M-channel symbol decision result Bm(k) and the S-channel symbol decision result Bs(k).

[0064] It should be noted that, Figure 6 The illustrated embodiments and Figure 4 , Figure 5The difference between the embodiments shown is that the calculation formula of Cm(k), Cs(k), P(k) is different, Figure 6 The calculation formula of Cm(k), Cs(k), P(k) in the embodiment shown is as follows:

[0065]

[0066] Figure 6 The embodiment shown is mainly to Figure 5 The double-frequency filtering unit 17 in the embodiment shown is replaced by two independent frequency filtering branches of M and S, and the frequency filtering results of the two branches are respectively subjected to waveform correlation operation, and the two filtering results are combined and subjected to symbol power calculation. The two embodiments can achieve the same effect, and compared with Figure 6 The embodiment shown, Figure 5 The frequency filtering operation of the embodiment shown is less, and does not need to increase the operation of combining two signals before power calculation.

[0067] In some embodiments of the present application, as Figure 7 shown, the M-path code word correlation and detection module 20 includes an M-path code word sliding correlation unit 21 and an M-path code word correlation peak detection unit 22. Wherein, the M-path code word sliding correlation unit 21 is used for sliding correlation of the code word reference sequence with the M-path symbol decision results of the plurality of symbols respectively, to obtain the M-path code word correlation results of each symbol; the M-path code word correlation peak detection unit 22 is used for performing correlation peak detection on the M-path code word correlation results of each symbol respectively, to obtain the M-path peak value information of each symbol.

[0068] Referring to Figure 7 , the M-path code word correlation and detection module 20 performs M-path code word sliding correlation calculation and correlation peak detection in units of symbols. Specifically, the M-path code word sliding correlation unit 21 performs sliding correlation of the M-path symbol decision results Bm(k) output by the demodulation and symbol decision module 10 with the code word reference sequence Seq(n) to obtain the M-path code word correlation results Qm(k), and the M-path code word correlation peak detection unit 22 performs correlation peak detection on Qm(k) to obtain the M-path peak value information Peak_m of each symbol. The peak value information includes peak value count Peak_m.cnt, peak value list Peak_m.ValList, next correlation peak state, etc. Wherein, the peak value count Peak_m.cnt is output to the link measurement module 40, and the peak value information Peak_m is output to the code word decision and confirmation module 50.

[0069] Specifically, the M-path code word sliding correlation unit 21 can multiply the nearest N M-path symbol decision results Bm(k) with Seq(n) and accumulate to obtain the M-path code word correlation results Qm(k) of the current symbol, and the calculation process is shown in formula (6):

[0070]

[0071] wherein Qm(k) represents the M-ary code word correlation result of the kth symbol, and Bm(k-n) represents the M-ary symbol decision result of the k-nth symbol.

[0072] By taking the last N M-ary symbol decision results Bm(k) for the sliding correlation, the same symbol is used for the sliding correlation to some extent, so that the performance loss can be avoided.

[0073] Each symbol updates the correlation peak value and index inside the M-ary code word correlation peak detection unit 22 with Qm(k), and performs subsequent corresponding processing according to the peak value count. If the peak value count is 0, the first correlation peak is detected, and the peak value count and peak value list and other information are updated after the first correlation peak is detected, and the correlation peak confirmation window is set; if the peak value count is greater than 0, the effectiveness of the next correlation peak is confirmed in the correlation peak confirmation window, and if the correlation peak is effective, the peak value list and other information are updated accordingly, and the correlation peak confirmation window is updated, and if the correlation peak is invalid, the peak value count is reset to 0; when the peak value count reaches Nword, the code word search is completed.

[0074] In some embodiments of the present application, as shown in Figure 8 The S-ary code word correlation and detection module 30 includes an S-ary code word sliding correlation unit 31 and an S-ary code word correlation peak detection unit 32. The S-ary code word sliding correlation unit 31 is configured to perform sliding correlation according to the code word reference sequence and the S-ary symbol decision results of the plurality of symbols to obtain S-ary code word correlation results of each symbol; and the S-ary code word correlation peak detection unit 32 is configured to perform correlation peak detection on the S-ary code word correlation results of each symbol respectively to obtain S-ary peak value information of each symbol.

[0075] Referring to Figure 8 , the S-ary code word correlation and detection module 30 performs S-ary code word sliding correlation calculation and correlation peak detection in units of symbols. Specifically, the S-ary code word correlation results Qs(k) are obtained by performing sliding correlation on the S-ary symbol decision results Bs(k) output by the demodulation and symbol decision module 10 and the code word reference sequence Seq(n), and the S-ary peak value information Peak_s of each symbol is obtained by performing correlation peak detection on Qs(k). The peak value information includes a peak value count Peak_s.cnt, a peak value list Peak_s.ValList, a next correlation peak state, etc. The peak value count Peak_s.cnt is output to the link measurement module 40, and the peak value information Peak_s is output to the code word decision and confirmation module 50.

[0076] Specifically, the S code word sliding correlation unit 31 can multiply the latest N S code symbol decision results Bs(k) and Seq(n) and accumulate to obtain the S code word correlation result Qs(k) of the current symbol, and the calculation process is shown in formula (7):

[0077]

[0078] wherein Qs(k) represents the S code word correlation result of the kth symbol, and Bs(k-n) represents the S code symbol decision result of the k-nth symbol.

[0079] Each symbol updates the correlation peak value and index in the S code word correlation peak detection unit 32, and the subsequent corresponding processing is performed according to the peak value count. If the peak value count is 0, the first correlation peak is detected, and the peak value count and peak value list and other information are updated after the first correlation peak is detected, and the correlation peak confirmation window is set; if the peak value count is greater than 0, the validity of the next correlation peak is confirmed in the correlation peak confirmation window, and if the correlation peak is valid, the peak value list and other information are updated accordingly, and the correlation peak confirmation window is updated, and if the correlation peak is invalid, the peak value count is reset to 0; when the peak value count reaches NWord, the code word search is completed.

[0080] In some embodiments of the present application, the code word reference sequence is obtained by repeating each element in the preset symbol sequence Nsym times.

[0081] Specifically, the code word reference sequence Seq(n) can be a +1, -1 sequence after slicing the logical code word 1 in units of symbols, which is used as a local reference sequence when the code word is slidingly correlated, and is obtained by expanding the preset symbol sequence (such as cws1) corresponding to logical 1 by symbol. Wherein, cws1 is a sequence with a length of NBitPerWord and elements of +1 or -1, each element of cws1 is repeated Nsym times, as shown in formula (8), that is, a code word reference sequence Seq(n) with a length of N=Nsym*NBitPerWord can be obtained, n=0:N-1. In the Sunspec protocol, NBitPerWord=11, +1 corresponds to the Fm frequency symbol, and -1 corresponds to the Fs frequency symbol, and cws1 is a Barker code sequence with a length of 11 as shown in formula (9).

[0082] Seq=kron(cws1,ones(1,Nsym)) (8)

[0083] cws1 =[-1,-1,-1,+1,+1,+1,-1,+1,+1,-1,+1] (9)

[0084] In some embodiments of the present application, for the kth symbol, the flow of correlation peak detection includes:

[0085] comparing the amplitude of the correlation result of the kth symbol with the correlation peak amplitude; if the amplitude of the correlation result is greater than the correlation peak amplitude, updating the correlation peak amplitude as the amplitude of the correlation result, and clearing the next correlation peak state, and then performing the correlation peak detection according to the peak value count, otherwise directly performing the correlation peak detection according to the peak value count.

[0086] wherein the performing the correlation peak detection according to the peak value count comprises: when the peak value count is 0, performing a first peak detection, and updating the peak value count and the peak value list after detecting the first correlation peak, clearing the next correlation peak state, and setting a correlation peak confirmation window; when the peak value count is greater than 0, performing validity confirmation of the next correlation peak within the correlation peak confirmation window, and updating the peak value count, the peak value list and the next correlation peak state; when the peak value count reaches a preset value, confirming that the correlation peak detection of the kth symbol is completed.

[0087] In some examples, the performing the first peak detection comprises: judging whether the correlation peak amplitude exceeds a correlation peak threshold and whether the correlation result appears a local downward trend; if yes, determining that the first correlation peak is detected.

[0088] wherein the updating the peak value count and the peak value list comprises: adding 1 to the peak value count, and recording the current correlation peak value at the first position of the peak value list.

[0089] In some examples, the setting the correlation peak confirmation window comprises: setting an initial value of a correlation peak confirmation window counter as a sum of a code word length and a correlation peak index allowable deviation.

[0090] In some examples, after determining that the first correlation peak is detected, the last valid correlation peak index is updated with a current correlation peak index, and a correlation peak expected index is updated according to the last valid correlation peak index and the code word length; the performing the validity confirmation of the next correlation peak within the correlation peak confirmation window, and updating the peak value count, the peak value list and the next correlation peak state comprises: obtaining a current correlation peak index deviation according to the correlation peak expected index and the current correlation peak index; judging whether the current correlation peak amplitude exceeds the correlation peak threshold, whether the correlation result appears the local downward trend, and whether the current correlation peak index deviation is not greater than a neighboring correlation peak position deviation tolerance threshold; if yes, determining that the next correlation peak is ready, updating the next correlation peak state from 0 to 1, and recording the current correlation peak value at a corresponding position of the peak value list; judging whether a count value of the correlation peak confirmation window counter is reduced to 0; if yes, judging whether the next correlation peak state is 1, otherwise reducing the count value of the correlation peak confirmation window counter by 1; if yes, determining that the next correlation peak is valid within the correlation peak confirmation window, and adding 1 to the peak value count, otherwise clearing the peak value count.

[0091] When the next correlation peak validity is confirmed, the periodicity of the adjacent code word correlation peak is used to set the peak deviation threshold and the peak position deviation threshold, so as to reduce the false alarm of the code word correlation peak decision and improve the reliability of the code word decision. Moreover, the peak detection state is set in advance and the peak count is updated in lag, and then the two-path code word search process is coordinated and synchronized based on the state, so that the decision results of the two paths can be used as much as possible when the final decision result is determined, and the decision reliability is improved.

[0092] In some examples, after determining that the first correlation peak is detected, the last correlation peak value is also updated with the current correlation peak value; and the validity confirmation of the next correlation peak in the correlation peak confirmation window further includes: obtaining a current correlation peak deviation according to the current correlation peak value and the last correlation peak value; judging whether the current correlation peak deviation is not greater than an adjacent correlation peak deviation tolerance threshold; and wherein, before determining that the next correlation peak is ready, it is further determined that the current correlation peak deviation is not greater than the adjacent correlation peak deviation tolerance threshold.

[0093] Specifically, the M-path code word correlation peak detection unit 22 and the S-path code word correlation peak detection unit 32 can adopt the same implementation when performing code word correlation peak detection, and the specific process is as shown in Figure 9 The parameters used and their meanings are shown in Table 1, the internal state in the detection process and its meaning are shown in Table 2, and the output parameters are shown in Table 3.

[0094] Table 1

[0095] Parameter name Parameter meaning Q(k) Current code word correlation result, Qm(k) for M paths, Qs(k) for S paths. cwThr Code word correlation peak decision threshold idxDifTol Adjacent correlation peak position deviation tolerance threshold valDifTol Adjacent correlation peak value deviation tolerance threshold idxDelayL Correlation peak decision short delay idxDelayH Correlation peak decision long delay N Constant, number of symbols contained in each code word, N = Nsym*NBitPerWord NWord Constant, number of code words corresponding to each instruction message, corresponding to the maximum number of correlation peaks

[0096] Table 2

[0097]

[0098]

[0099] Table 3

[0100]

[0101] As shown in Figure 9 , the code word correlation peak detection process is as follows:

[0102] Step C0, initialization: when performing code word correlation peak detection for the first time or starting to detect a new frame of instruction message, the internal state of the code word correlation peak detection unit is initialized, and peakVal, peakIdx, expectPeakIdx, chkCnt, peakReady, peakCnt, etc. are cleared;

[0103] Step C1, obtain the current code word correlation result Q(k) as the input for subsequent correlation peak detection;

[0104] Step C2, update of the correlation peak, including steps C21 and C22, etc.

[0105] Step C21, compare the amplitude of the current correlation result with the amplitude of the correlation peak, if the amplitude of the current correlation result is greater than the amplitude of the correlation peak (abs(Q(k))>abs(peakVal)), then execute C22, otherwise execute C3;

[0106] Step C22, update the correlation peak index with the current index (peakIdx=k), update the correlation peak value with the current correlation result (peakVal=Q(k)), and clear the next correlation peak state (peakReady=0);

[0107] Step C3, determine the subsequent correlation peak detection strategy according to the current peak value count, if the peak value count is 0 (peakCnt==0), then perform the first peak detection (C4); if the peak value count is greater than 0 and less than a preset value NWord (0<peakCnt<NWord), then execute the subsequent peak confirmation (C6); if the peak value count is equal to NWord (peakCnt==NWord), then determine that the correlation peak detection is completed, and end the current frame search (C5).

[0108] Step C4, first peak detection: determine whether the first correlation peak has appeared according to whether the current correlation peak exceeds the correlation peak threshold and whether the correlation result has appeared a local downward trend, which specifically includes C41-C44;

[0109] Step C41, judge whether the amplitude of the correlation peak exceeds the correlation peak threshold (abs(peakVal)>cwThr?) and whether the correlation result has appeared a local downward trend (k-peakIdx>=idxDelayH?), if both conditions are met, then execute C42, C43, and C44 in turn, otherwise directly execute C7;

[0110] Step C42, update the previous correlation peak value with the current correlation peak value (prePeakVal=peakVal), update the previous correlation peak index with the current correlation peak index (prePeakIdx=peakIdx), and record the current correlation peak value at the first position of the peak value list (ValList(peakCnt)=peakVal);

[0111] Step C43, calculate the expected peak index (expectPeakIdx = prePeakIdx + N) according to the peak index and the codeword length, and set the initial value of the peak confirmation window counter (chkCnt = idxDifTol + N) as the sum of the codeword length and the allowed deviation of the peak index, which is also called the length of the peak confirmation window;

[0112] Step C44, increment the peak count (peakCnt) by 1, and clear the peak value (peakVal), the peak index (peakIdx), the next peak state (peakReady), and the like, and then execute C7;

[0113] Step C5, the searched number of peaks reaches the expected number (peakCnt == NWord), and the current frame search is ended;

[0114] Step C6, subsequent peak confirmation: the validity of the next peak is confirmed within the peak confirmation window, including processes such as C61-C69;

[0115] Step C61, calculate the current peak value deviation (valDif = abs(abs(peakVal) - abs(prePeakVal))) and the current peak index deviation (idxDif = abs(peakIdx - expectPeakIdx));

[0116] Step C62, peak validity confirmation: determine whether the current peak satisfies the four conditions of the peak amplitude exceeding the peak threshold (abs(peakVal) > cwThr?), the local downward trend of the correlation result (k - peakIdx >= idxDelayL?), the current peak value deviation not being greater than the adjacent peak deviation tolerance threshold (valDif <= valDifTol), and the current peak index deviation not being greater than the adjacent peak position deviation tolerance threshold (idxDif <= idxDifTol), and if yes, execute C63, and if no, directly execute C65;

[0117] It should be noted that the condition of the peak value deviation not being greater than the adjacent peak deviation tolerance threshold can also be omitted, and accordingly the current peak value deviation can not be calculated in C61;

[0118] Step C63, set the next peak validity flag to 1, indicating that the next peak is ready;

[0119] Step C64, update the previous correlation peak value (prePeakVal = peakVal) and the previous correlation peak index (prePeakIdx = peakIdx) with the current correlation peak value and index, and record the current correlation peak value in the corresponding position of the peak value list (ValList(peakCnt) = peakVal);

[0120] Step C65, judge whether the correlation peak confirmation window counter is 0 (chkCnt == = 0?), if yes, execute C66, if not, decrease the correlation peak confirmation window counter by 1 and jump to C7;

[0121] Step C66, when the correlation peak confirmation window counter is 0, judge whether the next correlation peak is ready (peakReady == = 1?), if yes, execute C67 and the subsequent process, if not, clear the peak value count peakCnt (C69) and jump to C7;

[0122] Step C67, update the correlation peak expected index (expectPeakIdx = prePeakIdx + N) according to the correlation peak index and the codeword length, and update the correlation peak confirmation window counter initial value as the sum of the codeword length and the correlation peak index allowed deviation (chkCnt = idxDifTol + N);

[0123] Step C68, the peak value count peakCnt is increased by 1, and the internal states such as the correlation peak value peakVal, the correlation peak index peakIdx, and the next correlation peak state peakReady are cleared, and then C7 is executed;

[0124] Step C7, output the real-time detection result (ValList, peakCnt, peakReady) of the current symbol for processing by the downstream module;

[0125] Step C8, the symbol number k is increased by 1, and then return to step C1 to continue the correlation peak detection on the next symbol.

[0126] In some embodiments of the present application, the link measurement module 40 is specifically configured to: when the M-path peak value count of the symbol is 0, clear the M-path instruction time slot power of the symbol, and when the M-path peak value count of the symbol is not 0, accumulate the current symbol power of the symbol to the M-path instruction time slot power of the symbol; when the S-path peak value count of the symbol is 0, clear the S-path instruction time slot power of the symbol, and when the S-path peak value count of the symbol is not 0, accumulate the current symbol power of the symbol to the S-path instruction time slot power of the symbol.

[0127] Specifically, the link measurement module 40 updates the instruction time slot power in symbol units and transmits the measurement value and power value of the current symbol to the subsequent module for processing. It includes: updating the M-path instruction time slot power according to the M-path peak value count Peak_m.cnt, updating the S-path instruction time slot power according to the S-path peak value count Peak_s.cnt, outputting the M-path instruction time slot power WdPm, the S-path instruction time slot power WdPs, the current symbol M-path measurement value CurCm, the current symbol S-path measurement value CurCs, and the current symbol power CurP, and outputting the relevant processing results to the code word decision and confirmation module 50. As shown in Figure 10 The specific process can include:

[0128] D1, initialization: initializing the M-path instruction time slot power WdPm and the S-path instruction time slot power WdPs to zero;

[0129] D2, input: inputting the current symbol M-path measurement value Cm(k), the current symbol S-path measurement value Cs(k), and the symbol power P(k), as well as the M-path peak value count Peak_m.cnt and the S-path peak value count Peak_s.cnt;

[0130] D3, instruction time slot power update: if the M-path peak value count is 0, the M-path instruction time slot power is cleared, otherwise the current symbol power is accumulated to the M-path instruction time slot power, and the specific process is shown in formula (10); if the S-path peak value count is 0, the S-path instruction time slot power is cleared, otherwise the current symbol power is accumulated to the S-path instruction time slot power, and the specific process is shown in formula (11);

[0131]

[0132] D4, current symbol information update: updating the current symbol M-path measurement value CurCm, the current symbol S-path measurement value CurCs, and the current symbol power CurP with Cm(k), Cs(k), and P(k) respectively;

[0133] D5, output: outputting the current symbol WdPm, WdPs, CurCm, CurCs, CurP and other information for use by the subsequent module;

[0134] Wherein, when the code word decision is completed, WdPm and WdPs correspond to the power of the instruction time slot, and CurCm, CurCs, and CurP correspond to the measurement value and symbol power of one symbol of the mute time slot;

[0135] D6, symbol count k is incremented by 1 and jumps to step D2 for processing of the next symbol until the signal detection is completed.

[0136] In some embodiments of the present application, as Figure 11As shown, the code word decision and confirmation module 50 comprises a code word search completion decision unit 51, a code word decision unit 52, a co-frequency interference decision unit 53 and a decision result confirmation output unit 54.

[0137] The code word search completion decision unit 51 is configured to determine whether the code word search of the two paths is completed according to the peak value count in the M-path peak value information of the symbol, the next correlation peak state and the peak value count in the S-path peak value information, the next correlation peak state, and to synchronize the code word search processes of the two paths. The code word decision unit 52 is configured to make code word decision for the path whose code word search is completed according to the peak value polarity in the corresponding peak value list. The co-frequency interference decision unit 53 is configured to make co-frequency interference decision for the M path and the S path according to the M-path metric value, the S-path metric value, the symbol power, the M-path instruction time slot power and the S-path instruction time slot power of each symbol when the M-path code word decision result and the S-path code word decision result are both valid and different, to determine the path with co-frequency interference, and to set the code word decision result of the path with co-frequency interference as invalid. The decision result confirmation output unit 54 is configured to obtain the target instruction according to the validity of the code word decision results of the two paths.

[0138] In some examples, the code word search completion decision unit 51 is specifically configured to: when the peak value count of one of the M path and the S path of a symbol reaches a preset threshold, the peak value count of the other reaches the preset threshold minus 1, and the next correlation peak state of the other is 1, add 1 to the peak value count of the other and clear the next correlation peak state of the other; and when the M-path peak value count of a symbol reaches the preset threshold, determine that the M-path code word search of the symbol is completed; when the S-path peak value count of a symbol reaches the preset threshold, determine that the S-path code word search of the symbol is completed.

[0139] Specifically, when the M-path peak value count of a symbol reaches a preset threshold, the S-path peak value count reaches the preset threshold minus 1, and the S-path next correlation peak state is 1, add 1 to the S-path peak value count and clear the S-path next correlation peak state. At this time, the M-path peak value count and the S-path peak value count of the symbol both reach the preset threshold, and it can be determined that the M-path and S-path code word searches of the symbol are completed synchronously. Similarly, when the S-path peak value count of a symbol reaches a preset threshold, the M-path peak value count reaches the preset threshold minus 1, and the M-path next correlation peak state is 1, add 1 to the M-path peak value count and clear the M-path next correlation peak state. At this time, it can also be determined that the M-path and S-path code word searches of the symbol are completed synchronously. Through the synchronization of the M-path and S-path code word search processes, the reliability of subsequent processing can be improved.

[0140] In some examples, the code word search completion determination unit 51 is specifically further configured to: when the peak value counts of the M paths and the S paths of a symbol all reach the preset threshold, directly determine that the code word search of the M paths and the S paths of the symbol has been completed, and perform subsequent processing of the symbol based on the determination result, so as to ensure the reliability of signal detection; meanwhile, the code word search completion determination is continued for the next symbol.

[0141] In some examples, the code word search completion determination unit 51 is specifically further configured to: when the peak value count of one of the M paths and the S paths of a symbol reaches the preset threshold, and the difference between the peak value count of the other path and the preset threshold is greater than 1, determine that the code word search of the one path of the symbol has been completed, perform subsequent processing of the symbol based on the determination result, and perform code word search completion determination for the next symbol. In this way, the timeliness of signal detection can be improved.

[0142] In some examples, the code word determination unit 52 is specifically configured to: when the code word search of the M paths of a symbol is completed, determine that the M path code word determination result is valid, determine the M code word corresponding to the peak with positive polarity in the M path peak value list of the symbol as logical code word 1, determine the M code word corresponding to the peak with negative polarity in the M path peak value list of the symbol as logical code word 0, and convert all the obtained M code words into an M path instruction message; when the code word search of the S paths of a symbol is completed, determine that the S path code word determination result is valid, determine the S code word corresponding to the peak with positive polarity in the S path peak value list of the symbol as logical code word 0, determine the S code word corresponding to the peak with negative polarity in the S path peak value list of the symbol as logical code word 1, and convert all the obtained S code words into an S path instruction message.

[0143] In some examples, the co-frequency interference determination unit 53 is specifically configured to: when the M path instruction message and the S path instruction message of a symbol are equal, or one of the M path code word determination result and the S path code word determination result of the symbol is valid, determine that co-frequency interference determination is not needed; when the M path code word determination result and the S path code word determination result of a symbol are both valid, and the M path instruction message and the S path instruction message of the symbol are not equal, respectively convert the M path instruction message and the S path instruction message of the symbol into average power of 1 symbol according to the number of symbols corresponding to the instruction time slot duration, to obtain M path average power and S path average power; if the symbol power of the symbol is greater than the product of the M path average power and an interference power threshold, and the symbol power of the symbol is greater than the product of the S path average power and the interference power threshold, determine that there is interference, and when the product of the M path metric value of the symbol and an interference path threshold is greater than the S path metric value, determine that the M path is interfered, set the M path code word determination result as invalid, and when the product of the S path metric value of the symbol and the interference path threshold is greater than the M path metric value, determine that the S path is interfered, and set the S path code word determination result as invalid, wherein the interference power threshold and the interference path threshold are both less than 1.

[0144] The method updates the average power of the instruction time slot while searching the code word, calculates the metric value and average power of the idle time slot after the decision is finished, and performs interference detection based on the metric value and average power if necessary, and uses the interference detection result to exclude the decision result of the unreliable path, so that the method achieves the purpose of same-frequency interference detection with low complexity, and effectively improves the detection reliability in the presence of same-frequency interference.

[0145] In some examples, the decision result confirmation output unit 54 is specifically configured to: when both of the two-path code word decision results are valid and the instruction messages are equal, take any one of the two-path instruction messages as the target instruction; when one of the two-path code word decision results is valid, take the instruction message in the valid code word decision result as the target instruction; and when both of the two-path code word decision results are invalid, determine that the decision is wrong, and trigger re-detection of the signal.

[0146] Specifically, the code word decision and confirmation module 50 performs code word search completion determination in symbol units, and after the code word search is completed, performs code word decision and confirmation and outputs the final instruction message (i.e., the target instruction). As shown in FIG. 2, the code word decision and confirmation module 50 includes a code word search completion determination unit 51, a code word decision unit 52, a same-frequency interference determination unit 53, and a decision result confirmation output unit 54. The code word search completion determination unit 51 determines whether the code word search of the two paths is completed according to the M-path peak value information (Peak_m.cnt, Peak_m.lastReady) and the S-path peak value information (Peak_s.cnt, Peak_s.lastReady), and synchronizes the code word search processes of the two paths; the code word decision unit 52 performs code word decision according to the peak polarity in the peak value list (Peak_m.ValList, Peak_s.ValList) for the paths for which the code word search is completed; when the code word decision results of the M-path and S-path output by the code word decision unit 52 are both valid but not equal, the same-frequency interference determination unit 53 is further used to find the path for which the same-frequency interference exists and set the code word decision result of the path to be invalid; and finally, the decision result confirmation output unit 54 confirms the final code word decision result (i.e., the target instruction) according to the validity of the two-path code word decision results and outputs the final code word decision result. Figure 11 Figure 12 As shown in FIG. 3, the specific process is as follows:

[0147] The code word search completion determination unit 51 determines whether the M-path code word search is completed according to Peak_m.cnt and Peak_m.lastReady in the M-path peak value information, and determines whether the S-path code word search is completed according to Peak_s.cnt and Peak_s.lastReady in the S-path peak value information.

[0148] ​The cnt field in the peak information indicates the peak count searched by the corresponding path currently, and the lastReady field indicates the next relevant peak state (0 indicates that the next relevant peak is not searched, 1 indicates that the next relevant peak is searched and waits for a decision). Since each instruction time slot contains NWord code words, when cnt == NWord, it indicates that the code word search of the corresponding path is completed; when cnt == NWord-1 and lastReady == 1, it indicates that the code word search of the current path is about to be completed (all peaks are found, but it is not the last peak decision time), if the code word search of another path is completed at this time, it can be considered that the code word search of the current path is also completed. Here, the combination of cnt and lastReady is used to determine the completion of the code word search, which can conveniently synchronize the search progress of two paths, and can use the decision results of two paths as much as possible when there is a time difference in the decision progress of two paths, thereby improving the decision reliability. The code word search completion determination logic can be referred to the following code snippet:

[0149] if Peak_m.cnt == NWord && Peak_s.cnt == NWord-1 && Peak_s.lastReady == 1

[0150] Peak_s.cnt = Peak_s.cnt + 1;

[0151] Peak_s.lastReady = 0;

[0152] end % The code word search of the m path is completed, and the s path is about to be completed, so the s path is determined to be completed.

[0153] if Peak_s.cnt == NWord && Peak_m.cnt == NWord-1 && Peak_m.lastReady == 1

[0154] Peak_m.cnt = Peak_m.cnt + 1;

[0155] Peak_m.lastReady = 0;

[0156] end % The code word search of the s path is completed, and the m path is about to be completed, so the m path is determined to be completed.

[0157] if Peak_m.cnt == NWord || Peak_s.cnt == NWord

[0158] The code word search is completed, and subsequent decisions are performed;

[0159] else

[0160] The code word search is not completed, and the next symbol code word search is continued;

[0161] end

[0162] The code word decision unit 52 makes a code word decision on the path with the peak count of Nword after determining that the code word search is complete. The code word decision is made by the peak polarity in the peak list (Peak_m.ValList or Peak_s.ValList): for the M path, the code word corresponding to the peak with a positive peak polarity (≥0) is determined as the logic code word 1, and the code word corresponding to the peak with a negative peak polarity (<0) is determined as the logic code word 0, as shown in equation (12); for the S path, the code word corresponding to the peak with a positive peak polarity (≥0) is determined as the logic code word 0, and the code word corresponding to the peak with a negative peak polarity (<0) is determined as the logic code word 1, as shown in equation (13). The path with the peak count of Nword can determine Nword code words, which are converted into the instruction message (0 / 1 sequence is converted into a decimal number); the path with the peak count not being Nword is considered to have an unsuccessful code word search, and the instruction message thereof is set to -1 (invalid). The conversion of the code word into the instruction message is shown in equations (14) and (15).

[0163]

[0164] The co-channel interference determination unit 53 preliminarily determines the validity of msgM and msgS. If msgM and msgS are equal, or only one of msgM and msgS is valid, the co-channel interference determination is not needed, and the determination result confirmation output unit 54 is directly processed; if msgM and msgS are both valid but not equal, it is indicated that co-channel interference exists in one of the M path and the S path, and the co-channel interference signal and the signal of the path are just opposite to each other and offset, resulting in a wrong result being determined, at which time the co-channel interference determination is needed for the two paths, the path affected by the co-channel interference is screened out, and the result thereof is set to invalid (the instruction message is set to -1), and then the determination result confirmation output unit 54 is processed. The co-channel interference is determined based on the link measurement information (WdPm, WdPs, CurCm, CurCs, CurP) output by the link measurement module 40 at the moment when the code word search is complete. Since a plurality of symbols are additionally received after the moment when the code word search is complete, CurCm, CurCs, and CurP at the moment when the code word search is complete reflect the state of the quiet time slot, and WdPm and WdPs reflect the state of the instruction time slot. The path affected by the co-channel interference can be screened out by the difference between the states of the quiet time slot and the instruction time slot and the comparison between the two paths.

[0165] The co-channel interference decision step includes: (1) converting WdPm and WdPs into average power of 1 symbol, ActPm and ActPs, according to the number of symbols corresponding to the instruction time slot duration; (2) if CurP> ActPm*jamPwrThr and CurP> ActPs*jamPwrThr, it is considered that there is interference, and the path of the interference needs to be further determined, wherein jamPwrThr is an interference power threshold, and jamPwrThr is a number less than 1; (3) if CurCm*jamPathThr> CurCs, the M path is interfered, and msgM is set to -1; if CurCs*jamPathThr> CurCm, the S path is interfered, and msgS is set to -1, wherein jamPathThr is an interference path threshold, and jamPathThr is a number less than 1. The interference decision logic can be seen from the following code snippet:

[0166]

[0167] The decision result confirmation output unit 54 performs decision result confirmation on the validity of msgM and msgS processed by the co-channel interference determination unit 53, and outputs the final decision result (i.e. the target instruction). If msgM and msgS are both valid and equal, msgM is taken as the final decision result; if msgM is valid and msgS is invalid, msgM is taken as the final decision result; if msgS is valid and msgM is invalid, msgS is taken as the final decision result; if msgM and msgS are both invalid, an error is determined, and receiving and decision are performed again. The decision result confirmation and output logic can be seen from the following code snippet:

[0168]

[0169]

[0170] In some embodiments of the present application, as shown in Figure 13 The signal detection device 100 further includes an analog front-end processing module 60. The analog front-end processing module 60 is connected before the demodulation and symbol decision module 10, and is used to perform at least analog-to-digital conversion processing on the received signal to obtain a digital signal.

[0171] Optionally, the analog front-end processing module 60 can also perform filtering processing and power amplification processing on the received signal.

[0172] Specifically, referring to Figure 13The signal received by the signal detection device 100 can be an analog signal, such as a fast-off signal of a switch. The received signal A(t) in analog form can be filtered, power-amplified, and analog-to-digital converted by the analog front-end processing module 60 to obtain a digital signal D(i), which can be the target digital signal X(i) described above.

[0173] In some examples, as shown in FIG. 6, the analog front-end processing module 60 includes an analog filtering unit 61, a power amplification unit 62, and an analog-to-digital conversion unit 63. Figure 14

[0174] The analog filtering unit 61 is configured to filter the received signal; the power amplification unit 62 is configured to power-amplify the filtered signal; and the analog-to-digital conversion unit 63 is configured to analog-to-digital convert the power-amplified signal at a preset sampling rate to obtain a digital signal.

[0175] Specifically, as shown in FIG. 6, the analog filtering unit 61 performs anti-aliasing filtering on the received signal A(t) and preliminarily filters out out-of-band interference signals, and the power amplification unit 62 power-amplifies the analog-filtered signal at a preset gain. The analog-to-digital conversion unit 63 performs analog-to-digital conversion at a preset sampling rate to obtain a digitized signal waveform D(i). Figure 14 In some examples, as shown in FIG. 7, the analog front-end processing module 60 further includes a gain control unit 64.

[0176] Figure 15 The gain control unit 64 is configured to adjust the gain of the power amplification unit 62 according to the power of the target digital signal.

[0177] Specifically, as shown in FIG. 7, the analog filtering unit 61 performs anti-aliasing filtering on the received signal A(t) and preliminarily filters out out-of-band interference signals, and the power amplification unit 62 power-amplifies the analog-filtered signal at a gain given by the gain control unit 64. The analog-to-digital conversion unit 63 performs analog-to-digital conversion at a preset sampling rate to obtain a digitized signal waveform D(i). The gain control unit 64 tracks the deviation of the power of the digital signal D(i) from a reference power and adjusts the gain of the power amplification unit 62 accordingly.

[0178] Figure 15 In the example shown in FIG. 6, the preset gain of the power amplification unit 62 can be a fixed gain, and the gain value can be determined in advance according to the reception sensitivity and the maximum reception level and the circuit characteristics. Compared with the example shown in FIG. 7,

[0179] Figure 14 In the example shown in FIG. 6, the preset gain of the power amplification unit 62 can be a fixed gain, and the gain value can be determined in advance according to the reception sensitivity and the maximum reception level and the circuit characteristics. Compared with the example shown in FIG. 7, Figure 15 Figure 14 ​​​​In the shown example, the gain control unit 64 is omitted, which can simplify the design of the analog front-end circuit while ensuring that the receiver performance (sensitivity and maximum input level) still meets the requirements of the test specification. Figure 14 In the shown example, Figure 15 The shown example can automatically adjust the gain according to the signal power, which can make the receiver applicable to a larger range of received signals.

[0180] In some embodiments of the present application, as shown, Figure 16 The signal detection device 100 further includes a digital front-end processing module 70.

[0181] The digital front-end processing module 70 is connected between the analog front-end processing module 60 and the demodulation and symbol decision module 10, and is configured to filter and down-sample the digital signal, and transmit the processed digital signal to the demodulation and symbol decision module 10. The sampling rate after down-sampling is an integer multiple of the base frequency of the modulation frequency used by the received signal.

[0182] Specifically, before the digital signal D(i) output by the analog front-end processing module 60 is input to the demodulation and symbol decision module 10, the digital signal D(i) can be processed by digital filtering, sampling rate conversion, down-sampling, digital gain compensation, etc. to obtain a low sampling rate digital signal filtered from out-of-band interference.

[0183] For the selection of the sampling rate after down-sampling in the sampling rate conversion, the sampling rate (1 / Ts) after down-sampling can be set to satisfy the Nyquist baseband sampling theorem or the Nyquist bandpass sampling theorem, and the sampling rate can be set to be an integer multiple of the base frequency of Fm and Fs. If the present application is used for sunspec quick shutdown signal detection, the base frequency of Fm and Fs is 6.25 kHz, and the sampling rate is set to 400 kHz to satisfy the Nyquist baseband sampling theorem, or is set to 200 kHz or 100 kHz to satisfy the Nyquist bandpass sampling theorem. When the sampling rate is set to 400 kHz, Fm = 131.25 kHz and Fs = 143.75 kHz in subsequent processing; when the sampling rate is set to 200 kHz, Fm and Fs need to be converted to mirror frequencies, i.e., Fm = 68.75 kHz and Fs = 56.25 kHz in subsequent processing; and when the sampling rate is set to 100 kHz, Fm and Fs need to be converted to mirror frequencies, i.e., Fm = 31.25 kHz and Fs = 43.75 kHz in subsequent processing. It should be noted that the present application is not limited to the detection of sunspec signals, but can also be used for the detection of other similar signals modulated by sfsk; when used for the detection of other similar schemes, a suitable sampling rate can be selected according to the frequencies of Fm and Fs according to the above principles. It should be noted again that the sampling rates listed in the present embodiment are only for the convenience of subsequent description, and other sampling rates that satisfy the above principles are also applicable to the present application.

[0184] For digital filtering and down-sampling processing, the digital filtering and down-sampling can be one-time "filtering + down-sampling" processing or a cascade of multiple "filtering + down-sampling" processing, and the filter can adopt any form, including but not limited to CIC (Cascade Integrator Comb), FIR (Finite Impulse Response), etc. The design of the digital filter and the down-sampling scheme can be reasonably selected according to the sampling rate relationship before and after input and output and the range of the passband frequency band according to the general theory of signal processing, and the present application does not limit the specific implementation manner.

[0185] It should be noted that the sampling rate of the analog-to-digital conversion unit 63 in the analog front-end processing module 60 is low and meets the sampling rate requirement of the input signal of the demodulation and symbol decision module 10, and therefore the digital front-end processing module 70 can be omitted, i.e., the embodiment shown in FIG. 6 is implemented. Figure 13

[0186] The signal detection device of the present embodiment can achieve the following effects:

[0187] ​1) The code word decision is based on the good autocorrelation of the symbol sequence constituting the code word and the periodicity between code words, which reduces the requirement for symbol decision reliability, avoids the complex adaptive update of symbol decision threshold, and reduces the complexity;

[0188] 2) The symbol and code word decisions are independently performed on two frequency paths of the signal, which effectively improves the detection performance when one path is interfered, avoids the complex path optimization algorithm or two-path joint decision algorithm, and reduces the implementation complexity;

[0189] 3) The periodicity of adjacent code word correlation peaks is used to set peak deviation threshold and peak position deviation threshold to reduce the false alarm of code word correlation peak decision and improve the reliability of code word decision;

[0190] 4) The peak detection state is set in advance and the peak counting update is performed with a lag, and based on this, the coordination and synchronization of the two-path code word search process are performed, so that the decision results of the two paths can be used as much as possible when the final decision result is determined, and the decision reliability is improved;

[0191] 5) The instruction time slot average power is updated while the code word search is performed, the metric value and average power of the idle time slot are calculated after the decision is completed, and if necessary, the interference detection is performed based on this, and the decision result of the unreliable path is excluded using the interference detection result, which achieves the purpose of same frequency interference detection with low complexity and effectively improves the detection reliability in the presence of same frequency interference;

[0192] 6) The simplified coherent demodulation is used for symbol demodulation and decision, which only needs to input frequency coherent signal as the demodulation reference signal, without requiring phase coherent reference signal, effectively reducing the implementation complexity; compared with envelope detection and zero-crossing detection, the decision reliability is effectively improved;

[0193] 7) Each symbol is divided into several symbols for decision in the symbol demodulation and decision stage, which can avoid complex symbol timing synchronization processing, and in the code word decision stage, the multiple symbols of the same symbol are used for sliding correlation, avoiding performance loss;

[0194] 8) The out-of-band interference signal is filtered out by frequency selection filtering, which effectively improves the detection performance in the presence of in-band interference, and the double frequency selection filtering is used to realize the simultaneous filtering of the two paths, which can reduce the computational load by half while ensuring the anti-interference performance;

[0195] 9) In the symbol decision stage, two frequency channels are used to make validity decision respectively, instead of directly determining which frequency is currently transmitted in the symbol. In combination with the false alarm processing of the subsequent code word decision algorithm, a certain false alarm probability can be allowed in the symbol validity decision, which is lower in the threshold requirement of symbol decision, and the same symbol decision threshold can be conveniently used in different interference scenarios, reducing the implementation complexity.

[0196] 10) Real-time metric value and power information are used for symbol decision, and then code word decision, without the need to maintain complex historical information and the need to maintain the periodic timing of the entire communication frame, reducing the implementation difficulty.

[0197] In summary, on the basis of frequency selection filtering, the two-step method of symbol validity decision and code word peak value detection in each channel (M channel, S channel) is used to realize the preliminary decision of the code word. After the code word decision is completed, the two-channel decision progress is synchronized, and simple co-frequency interference detection is used to remove unreliable results, so that reliable decision results can be obtained. The whole process has low implementation complexity and high reliability.

[0198] Figure 17 is a structural block diagram of a receiver of an embodiment of the present application.

[0199] As shown in Figure 17 , the receiver 1000 includes the signal detection device 100 of the above embodiment.

[0200] Figure 18 is a flowchart of a signal detection method of an embodiment of the present application.

[0201] As shown in Figure 18 , the signal detection method includes:

[0202] S1, grouping the target digital signal to obtain a plurality of symbols, coherently demodulating and symbol deciding the plurality of symbols respectively to obtain the M channel metric value, the S channel metric value, the symbol power, the M channel symbol decision result and the S channel symbol decision result of each symbol.

[0203] S2, correlating the code word reference sequence with the M channel symbol decision result of each symbol respectively, and performing correlation peak detection on each correlation result respectively to obtain the M channel peak value information of each symbol, and correlating the code word reference sequence with the S channel symbol decision result of each symbol respectively, and performing correlation peak detection on each correlation result respectively to obtain the S channel peak value information of each symbol.

[0204] S3, obtaining the M channel instruction time slot power of each symbol according to the symbol power of each symbol and the M channel peak value count in the M channel peak value information, and obtaining the S channel instruction time slot power of each symbol according to the symbol power of each symbol and the S channel peak value count in the S channel peak value information.

[0205] S4, respectively according to the M-path peak value information and the S-path peak value information of each symbol, M-path code word decision results and S-path code word decision results are obtained, and according to the M-path metric value and the S-path metric value of each symbol, the symbol power, the M-path instruction time slot power and the S-path instruction time slot power, co-channel interference determination is performed on the M-path and the S-path, and according to the co-channel interference determination result of each symbol, the M-path code word decision result and the S-path code word decision result, target instructions are obtained.

[0206] In some embodiments of the present application, step S1 can include:

[0207] Points in the target digital signal are assigned symbols, and one symbol is assigned for every preset number of points, and a plurality of symbols are obtained; the M-path waveform in each symbol is coherently demodulated respectively, and the M-path metric value of each symbol is obtained; the S-path waveform in each symbol is coherently demodulated respectively, and the S-path metric value of each symbol is obtained; the symbol power of each symbol is obtained by performing average power solving on each symbol respectively; the M-path symbol decision result of each symbol is obtained according to the M-path metric value and the symbol power of each symbol; and the S-path symbol decision result of each symbol is obtained according to the S-path metric value and the symbol power of each symbol.

[0208] In some embodiments of the present application, before the target digital signal is grouped, the target digital signal is also subjected to double selective frequency filtering.

[0209] In some embodiments of the present application, before the target digital signal is grouped, the target digital signal is also subjected to M-path selective frequency filtering and S-path selective frequency filtering. Before the average power solving is performed, the grouping results of the M-path selective frequency filtered signal and the grouping results of the S-path selective frequency filtered signal are also summed.

[0210] In some embodiments of the present application, the M-path metric value, the S-path metric value, the symbol power, the M-path symbol decision result and the S-path symbol decision result of each symbol are obtained by the following formulas respectively:

[0211]

[0212] Wherein, Cm(k), Cs(k), P(k), Bm(k), Bs(k) represent the M-path metric value, the S-path metric value, the symbol power, the M-path symbol decision result and the S-path symbol decision result of the kth symbol respectively, Lsym represents the preset value, Y(k, l) represents the signal of the lth sampling point of the kth symbol, e 2πi*Fm*l*Ts represents a complex signal with a frequency of Fm, e 2πi*Fs*l*Ts represents a complex signal with a frequency of Fs, i represents an imaginary unit, Ts represents a sampling period, and bitThr represents a bit decision threshold.

[0213] In some embodiments of the present application, step S2 comprises:

[0214] performing sliding correlation according to the code word reference sequence and the M-path symbol decision results of the plurality of symbols to obtain M-path code word correlation results of each symbol; performing correlation peak detection on the M-path code word correlation results of each symbol respectively to obtain M-path peak value information of each symbol; and

[0215] performing sliding correlation according to the code word reference sequence and the S-path symbol decision results of the plurality of symbols to obtain S-path code word correlation results of each symbol; performing correlation peak detection on the S-path code word correlation results of each symbol respectively to obtain S-path peak value information of each symbol.

[0216] In some embodiments of the present application, the M-path code word correlation results and the S-path code word correlation results of the symbol are respectively represented by the following formula:

[0217]

[0218] wherein Qm(k), Qs(k) represent the M-path code word correlation results and the S-path code word correlation results of the kth symbol respectively, Bm(k-n), Bs(k-n) represent the M-path symbol decision results and the S-path symbol decision results of the k-nth symbol respectively, N is an integer greater than 1, and Seq(N-1-n) represents the (N-1-n)th value in the code word reference sequence.

[0219] In some embodiments of the present application, the peak value information further comprises a peak value list and a next correlation peak state; and the procedure of the correlation peak detection for the kth symbol comprises: comparing the amplitude of the correlation result of the kth symbol with a correlation peak amplitude; if the amplitude of the correlation result is greater than the correlation peak amplitude, updating the correlation peak amplitude to the amplitude of the correlation result, clearing the next correlation peak state, and then performing the correlation peak detection according to the peak value count, otherwise directly performing the correlation peak detection according to the peak value count.

[0220] wherein the performing the correlation peak detection according to the peak value count comprises: when the peak value count is 0, performing a first peak detection, updating the peak value count and the peak value list, clearing the next correlation peak state, and setting a correlation peak confirmation window after detecting the first correlation peak; when the peak value count is greater than 0, confirming the effectiveness of the next correlation peak within the correlation peak confirmation window, and updating the peak value count, the peak value list and the next correlation peak state; and when the peak value count reaches a preset value, confirming that the correlation peak detection for the kth symbol is completed.

[0221] In some embodiments of the present application, the performing the first peak detection comprises: judging whether the correlation peak amplitude exceeds a correlation peak threshold and whether the correlation result appears a local downward trend; if yes, it is determined that the first correlation peak is detected.

[0222] The updating of the peak value count and the peak value list includes: adding 1 to the peak value count and recording the current correlation peak at the first position of the peak value list.

[0223] By setting the first peak detection condition as the correlation peak amplitude exceeding the correlation peak threshold and the correlation result having a local downward trend, it is ensured that the detected correlation peak is a local correlation peak.

[0224] In some embodiments of the present application, the correlation peak confirmation window is set by setting an initial value of a correlation peak confirmation window counter to a sum of the code word length and the correlation peak index allowable deviation.

[0225] In some embodiments of the present application, after detecting the first correlation peak, the last valid correlation peak index is updated with the current correlation peak index, and the correlation peak expected index is updated according to the last valid correlation peak index and the code word length; the validity of the next correlation peak is confirmed within the correlation peak confirmation window, and the peak value count, the peak value list and the next correlation peak state are updated, including: obtaining the current correlation peak index deviation according to the correlation peak expected index and the current correlation peak index; judging whether the current correlation peak amplitude exceeds the correlation peak threshold, whether the correlation result has a local downward trend, and whether the current correlation peak index deviation is not greater than the adjacent correlation peak position deviation tolerance threshold; if yes, it is determined that the next correlation peak is ready, the next correlation peak state is updated from 0 to 1, and the current correlation peak value is recorded at the corresponding position of the peak value list; judging whether the count value of the correlation peak confirmation window counter is reduced to 0; if yes, judging whether the next correlation peak state is 1, otherwise reducing the count value of the correlation peak confirmation window counter by 1; if yes, it is determined that the next correlation peak is valid within the correlation peak confirmation window, and the peak value count is added by 1, otherwise the peak value count is cleared.

[0226] In some embodiments of the present application, after detecting the first correlation peak, the last correlation peak value is updated with the current correlation peak value; the validity of the next correlation peak is confirmed within the correlation peak confirmation window, and the current correlation peak deviation is obtained according to the current correlation peak value and the last correlation peak value; it is judged whether the current correlation peak deviation is not greater than the adjacent correlation peak deviation tolerance threshold; wherein, before determining that the next correlation peak is ready, it is also determined that the current correlation peak deviation is not greater than the adjacent correlation peak deviation tolerance threshold.

[0227] In some embodiments of the present application, step S3 comprises:

[0228] when the M-path peak value count of the symbol is 0, clearing the M-path instruction slot power of the symbol, and when the M-path peak value count of the symbol is not 0, accumulating the current symbol power of the symbol to the M-path instruction slot power of the symbol; when the S-path peak value count of the symbol is 0, clearing the S-path instruction slot power of the symbol, and when the S-path peak value count of the symbol is not 0, accumulating the current symbol power of the symbol to the S-path instruction slot power of the symbol.

[0229] In some embodiments of the present application, step S4 comprises:

[0230] According to the peak count in the M-path peak value information of the symbol, the next relevant peak state and the peak count in the S-path peak value information of the symbol, the next relevant peak state, it is judged whether the two-path code word search is completed, and the code word search processes of the two paths are synchronized; according to the peak polarity in the corresponding peak value list, the code word decision of the path whose code word search is completed is performed; when the M-path code word decision result and the S-path code word decision result are both valid and different, according to the M-path metric value, the S-path metric value, the symbol power, the M-path instruction slot power and the S-path instruction slot power of each symbol, the co-frequency interference of the M-path and the S-path is determined, so as to determine the path with co-frequency interference, and the code word decision result of the path with co-frequency interference is set to be invalid; according to the validity of the two-path code word decision results, the target instruction is obtained.

[0231] In some embodiments of the present application, when the peak count of one of the M-path and the S-path of the symbol reaches a preset threshold, the peak count of the other one reaches the preset threshold minus 1, and the next relevant peak state of the other one is 1, the peak count of the other one is increased by 1, and the next relevant peak state of the other one is cleared; when the M-path peak count of the symbol reaches the preset threshold, it is determined that the M-path code word search of the symbol is completed; when the S-path peak count of the symbol reaches the preset threshold, it is determined that the S-path code word search of the symbol is completed.

[0232] In some embodiments of the present application, when the M-path code word search of the symbol is completed, it is determined that the M-path code word decision result is valid, the M code word corresponding to the peak with positive peak polarity in the M-path peak value list of the symbol is determined as the logic code 1, the M code word corresponding to the peak with negative peak polarity is determined as the logic code 0, and all the obtained M code words are converted into the M-path instruction message; when the S-path code word search of the symbol is completed, it is determined that the S-path code word decision result is valid, the S code word corresponding to the peak with positive peak polarity in the S-path peak value list of the symbol is determined as the logic code 0, the S code word corresponding to the peak with negative peak polarity is determined as the logic code 1, and all the obtained S code words are converted into the S-path instruction message.

[0233] In some embodiments of the present application, when the M-way instruction message and the S-way instruction message of a symbol are equal, or when one of the M-way code word decision result and the S-way code word decision result of a symbol is valid, it is determined that the co-frequency interference judgment is not needed; when the M-way code word decision result and the S-way code word decision result of a symbol are both valid, and the M-way instruction message and the S-way instruction message of a symbol are not equal, the M-way instruction message and the S-way instruction message of a symbol are converted into the average power of one symbol according to the number of symbols corresponding to the instruction time slot duration, respectively, to obtain the M-way average power and the S-way average power; if the symbol power of a symbol is greater than the product of the M-way average power and the interference power threshold, and the symbol power of a symbol is greater than the product of the S-way average power and the interference power threshold, it is determined that there is interference, and when the product of the M-way metric value of a symbol and the interference path threshold is greater than the S-way metric value, it is determined that the M way is interfered, and the M-way code word decision result is set to be invalid, and when the product of the S-way metric value of a symbol and the interference path threshold is greater than the M-way metric value, it is determined that the S way is interfered, and the S-way code word decision result is set to be invalid, wherein the interference power threshold and the interference path threshold are both less than 1.

[0234] In some embodiments of the present application, when the two-way code word decision results are both valid, and the instruction messages are equal, any one of the two-way instruction messages is taken as the target instruction; when one of the two-way code word decision results is valid, the instruction message in the valid code word decision result is taken as the target instruction; when the two-way code word decision results are both invalid, it is determined that the judgment is wrong, and the signal detection is triggered to be performed again.

[0235] The code word reference sequence is obtained by repeating each element in a preset symbol sequence for a preset value times.

[0236] In some embodiments of the present application, the signal detection method further comprises: performing at least analog-to-digital conversion processing on the received signal to obtain a digital signal, and taking the digital signal as the target digital signal.

[0237] In some embodiments of the present application, the received signal is further processed by filtering, and the signal processed by filtering is processed by power amplification, and then the signal processed by power amplification is converted into a digital signal by analog-to-digital conversion at a preset sampling rate.

[0238] In this embodiment, the gain of the power amplification unit can also be adjusted according to the power of the target digital signal.

[0239] In some embodiments of the present application, the digital signal is further processed by filtering and down-sampling, and the processed digital signal is taken as the target digital signal, wherein the sampling rate after down-sampling is an integer multiple of the base frequency of the modulation frequency used by the received signal.

[0240] It should be noted that other specific embodiments of the signal detection method of the embodiments of the present application can refer to the specific embodiments of the signal detection device of the embodiments of the present application described above.

[0241] Figure 19 is a structural block diagram of a chip of the embodiments of the present application.

[0242] As shown in Figure 19 , the chip 500 includes a processor 501 and a memory 503. The processor 501 and the memory 503 are connected, for example, through a bus 502. Optionally, the chip 500 can also include a transceiver 504. It should be noted that the transceiver 504 is not limited to one in actual application, and the structure of the chip 500 does not constitute a limitation on the embodiments of the present application.

[0243] The processor 501 can be a CPU (Central Processing Unit, central processor), a general-purpose processor, a DSP (Digital Signal Processor, digital signal processor), an ASIC (Application Specific Integrated Circuit, application specific integrated circuit), an FPGA (Field Programmable Gate Array, field programmable gate array) or other programmable logic devices, transistor logic devices, hardware components or any combination thereof. It can implement or execute various exemplary logical blocks, modules and circuits described in combination with the disclosure content of the present application. The processor 501 can also be a combination of computing functions, such as one or more microprocessor combinations, combinations of DSP and microprocessor, etc.

[0244] The bus 502 can include a channel for transmitting information between the above-mentioned components. The bus 502 can be a PCI (Peripheral Component Interconnect, peripheral component interconnect) bus or an EISA (Extended Industry Standard Architecture, extended industry standard architecture) bus, etc. The bus 502 can be divided into an address bus, a data bus, a control bus, etc. For the sake of convenience, Figure 19 only one thick line is used in the figure, but it does not mean that there is only one bus or only one type of bus.

[0245] The memory 503 is used to store a computer program corresponding to the signal detection method of the embodiments of the present application described above, which is controlled and executed by the processor 501. The processor 501 is used to execute the computer program stored in the memory 503 to realize the content shown in the foregoing method embodiments.

[0246] The chip 500 includes, but is not limited to, a mobile terminal of a mobile phone, a notebook computer, a digital broadcast receiver, a PDA (Personal Digital Assistant), a PAD (a tablet computer), a PMP (a Portable Multimedia Player), a car terminal (for example, a car navigation terminal), and the like, and a stationary terminal such as a digital TV, a desktop computer, and the like. Figure 19 The illustrated chip 500 is merely an example and should not impose any limitation on the functions and use range of the embodiments of the present application.

[0247] It is noted that the logic and / or steps represented in the flowcharts or otherwise described herein, for example, can be considered as a list of executable instructions for implementing logic functions, and can be embodied in any computer-readable medium for use by or in connection with an instruction execution system, apparatus, or device, such as a computer-based system, processor- based system, or other system that can fetch the instructions from the instruction execution system, apparatus, or device and execute the instructions, or a combination of the instruction execution system, apparatus, or device. For the purposes of this specification, a "computer-readable medium" can be any signal-bearing medium that can contain, store, communicate, propagate, or transport the program for use by or in connection with the instruction execution system, apparatus, or device. More specific examples (a non-exhaustive list) of the computer-readable medium include the following: an electrical connection having one or more wires (electrical devices), a portable computer diskette (magnetic devices), a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or Flash memory), an optical fiber (optical devices), and a portable compact disc read-only memory (CDROM). In addition, the computer-readable medium can even be paper or another suitable medium upon which the program is printed, as the program can be electronically captured, for example, via the optical scanning of the paper or other medium, then compiled, interpreted, or otherwise processed in a suitable manner, if necessary, and stored in a computer memory.

[0248] It is understood that portions of the present application can be implemented in hardware, software, firmware, or a combination thereof. In the above-described embodiments, a plurality of steps or methods can be implemented in software or firmware stored in a memory and executed by a suitable instruction execution system. For example, if implemented in hardware, and as in another embodiment, any of the following technologies known in the art or a combination thereof can be used: discrete logic circuitry having logic gates for implementing logic functions on data signals, application specific integrated circuits having appropriate combinational logic gates, programmable gate arrays (PGA), field programmable gate arrays (FPGA), and the like.

[0249] In the description of the specification, the description of the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" and the like means that the specific features, structures, materials or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present application. In the description of the specification, the illustrative description of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0250] In the description of the present application, it should be understood that the orientation or positional relationship indicated by the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like is based on the orientation or positional relationship shown in the drawings, and is only for the purpose of facilitating the description of the present application and simplifying the description, and does not indicate or imply that the signal detection device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation of the present application.

[0251] In addition, the terms "first", "second" are only for the purpose of description, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features referred to. Therefore, the features defined with "first", "second" can explicitly or implicitly include at least one of the features. In the description of the present application, the meaning of "a plurality of" is at least two, for example, two, three, etc., unless otherwise explicitly specified and limited.

[0252] In the present application, unless otherwise explicitly specified and limited, the terms "mounting", "connection", "connection", "fixing" and the like should be understood in a broad sense, for example, it can be fixed connection, or detachable connection, or integral; it can be mechanical connection, or electrical connection; it can be directly connected, or indirectly connected through an intermediate medium; it can be the internal communication of two elements or the interaction relationship between two elements, unless otherwise explicitly limited. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0253] In the present application, unless specifically stated and limited otherwise, a first feature "on" or "under" a second feature can be directly in contact with the second feature, or indirectly in contact with the second feature through an intermediate medium. Also, a first feature "over", "above" and "on top of" a second feature can be directly above or obliquely above the second feature, or simply means that the first feature is horizontally higher than the second feature. A first feature "under", "below" and "underneath" a second feature can be directly below or obliquely below the second feature, or simply means that the first feature is horizontally lower than the second feature.

[0254] Although the embodiments of the present application have been shown and described above, it should be understood by those skilled in the art that the above-described embodiments are exemplary, and cannot be construed as limiting the present application, and those skilled in the art can make changes, modifications, replacements and variations to the above-described embodiments within the scope of the present application.

Claims

1. A signal detection device, characterized in that, include: The demodulation and symbol decision module is used to group the target digital signal into multiple symbols, and to perform coherent demodulation and symbol decision on the multiple symbols respectively, so as to obtain the M-channel metric value, S-channel metric value, symbol power, M-channel symbol decision result and S-channel symbol decision result for each symbol. The M-way codeword correlation and detection module is used to correlate the codeword reference sequence with the M-way symbol decision results of the multiple symbols respectively, and to perform correlation peak detection on each correlation result to obtain the M-way peak information of each symbol. The S-way codeword correlation and detection module is used to correlate the S-way symbol decision results of the codeword reference sequence for the multiple symbols respectively, and to perform correlation peak detection on each correlation result to obtain the S-way peak information of each symbol. The link measurement module is used to obtain the M-path command time slot power of the symbol based on the symbol power of each symbol and the M-path peak count in the M-path peak information, and to obtain the S-path command time slot power of the symbol based on the symbol power of each symbol and the S-path peak count in the S-path peak information; The codeword decision and confirmation module is used to make codeword decisions based on the M-channel peak information and S-channel peak information of each symbol, to obtain M-channel codeword decision results and S-channel codeword decision results, and to perform co-channel interference determination on the M-channel and S-channel based on the M-channel metric value, S-channel metric value, symbol power, M-channel command time slot power and S-channel command time slot power of each symbol, and to obtain the target command based on the co-channel interference determination result, M-channel codeword decision result and S-channel codeword decision result of each symbol.

2. The signal detection device according to claim 1, characterized in that, The demodulation and symbol decision module includes: A grouping unit is used to assign symbols to points in the target digital signal, and assign one symbol to every preset number of points to obtain the plurality of symbols; M-channel waveform correlation unit, used to coherently demodulate the M-channel waveforms in each symbol to obtain the M-channel metric values ​​of each symbol; The S-channel waveform correlation unit is used to coherently demodulate the S-channel waveform in each symbol to obtain the S-channel metric value of each symbol. An average power unit is used to calculate the average power for each symbol to obtain the symbol power of each symbol. The M-way symbol decision unit is used to obtain the M-way symbol decision result of each symbol based on the M-way metric value and symbol power of each symbol. The S-way symbol decision unit is used to obtain the S-way symbol decision result of each symbol based on the S-way metric value and symbol power of each symbol.

3. The signal detection device according to claim 2, characterized in that, The demodulation and symbol decision module also includes: A dual-frequency selective filtering unit is connected before the grouping unit to perform dual-frequency selective filtering on the target digital signal and transmit the dual-frequency selective filtered signal to the grouping unit.

4. The signal detection device according to claim 2, characterized in that, The grouping unit includes a first grouping subunit and a second grouping subunit; the demodulation and symbol decision module further includes: The M-channel frequency selective filtering unit is used to perform M-channel frequency selective filtering on the target digital signal. The first grouping subunit is used to assign symbols to points in the M-channel frequency selective filtered signal, and one symbol is assigned to each preset number of points. The S-channel frequency selective filtering unit is used to perform S-channel frequency selective filtering on the target digital signal. The second grouping subunit is used to assign symbols to points in the S-channel frequency selective filtered signal, and one symbol is assigned to each preset number of points. The summation unit is connected to the first grouping subunit, the second grouping subunit, and the average power unit, respectively, and is used to sum the grouping results of the M-channel frequency-selective filtered signals and the grouping results of the S-channel frequency-selective filtered signals, and output the summation result to the average power unit.

5. The signal detection device according to claim 2, characterized in that, The M-way metric value, S-way metric value, symbol power, M-way symbol decision result, and S-way symbol decision result of the symbol are obtained by the following formulas: in, , , , , Let M-way metric value, S-way metric value, symbol power, M-way symbol decision result, and S-way symbol decision result be represented respectively for the k-th symbol. This represents the preset value. This represents the signal at the l-th sampling point of the k-th symbol. Indicates frequency as Complex signal, Indicates frequency as A complex signal, where i represents the imaginary unit. Indicates the sampling period. This represents the bit decision threshold.

6. The signal detection device according to claim 1, characterized in that, The M-way codeword correlation detection module includes: The M-way codeword sliding correlation unit is used to perform sliding correlation based on the codeword reference sequence and the M-way symbol decision results of the plurality of symbols to obtain the M-way codeword correlation result for each symbol; The M-way codeword correlation peak detection unit is used to perform correlation peak detection on the M-way codeword correlation results of each symbol to obtain the M-way peak information of each symbol.

7. The signal detection device according to claim 1, characterized in that, The S-codeword related detection module includes: The S-way codeword sliding correlation unit is used to perform sliding correlation based on the codeword reference sequence and the S-way symbol decision results of the plurality of symbols to obtain the S-way codeword correlation result for each symbol. The S-way codeword correlation peak detection unit is used to perform correlation peak detection on the S-way codeword correlation results of each symbol to obtain the S-way peak information of each symbol.

8. The signal detection device according to claim 1, characterized in that, The M-way codeword correlation results and S-way codeword correlation results of the symbol are respectively expressed by the following formulas: in, , These represent the M-way codeword correlation results and S-way codeword correlation results for the k-th symbol, respectively. , Let M and S represent the decision results of the M-way and S-way symbols for the kn-th symbol, respectively, where N is an integer greater than 1. Indicates the first codeword in the reference sequence Values.

9. The signal detection device according to claim 1, characterized in that, Peak information also includes a list of peaks and the status of the next relevant peak; For the k-th symbol, the correlation peak detection process includes: Compare the magnitude of the correlation result of the k-th symbol with the magnitude of the correlation peak; If the magnitude of the correlation result is greater than the magnitude of the correlation peak, then the magnitude of the correlation peak is updated to the magnitude of the correlation result, and the state of the next correlation peak is cleared to zero. Then, correlation peak detection is performed based on the peak count. Otherwise, correlation peak detection is performed directly based on the peak count. The step of detecting relevant peaks based on peak counts includes: When the peak count is 0, the first peak is detected, and after the first related peak is detected, the peak count and peak list are updated, the status of the next related peak is cleared, and a related peak confirmation window is set. When the peak count is greater than 0, the validity of the next related peak is confirmed in the related peak confirmation window, and the peak count, peak list and the status of the next related peak are updated. When the peak count reaches the pre-designed value, it is confirmed that the detection of the relevant peak of the k-th symbol is complete.

10. The signal detection device according to claim 9, characterized in that, The first peak detection includes: Determine whether the amplitude of the relevant peak exceeds the relevant peak threshold, and whether the relevant results show a local downward trend; If the amplitude of the correlation peak exceeds the correlation peak threshold and the correlation result shows a local downward trend, then the first correlation peak is detected. The updating of peak counts and peak lists includes: Increment the peak count by 1 and record the current relevant peak in the first position of the peak list.

11. The signal detection device according to claim 10, characterized in that, The setting of the relevant peak confirmation window includes: Set the initial value of the correlation peak confirmation window counter to the sum of the codeword length and the allowable deviation of the correlation peak index.

12. The signal detection device according to claim 10, characterized in that, After determining that the first relevant peak has been detected, the previous valid relevant peak index is updated with the current relevant peak index, and the expected relevant peak index is updated according to the previous valid relevant peak index and the codeword length; the validity confirmation of the next relevant peak within the relevant peak confirmation window, and the updating of the peak count, peak list and next relevant peak status, include: The current correlation peak index deviation is obtained based on the expected correlation peak index and the current correlation peak index. Determine whether the amplitude of the current relevant peak exceeds the relevant peak threshold, whether the relevant results show a local downward trend, and whether the current relevant peak index deviation is not greater than the tolerance threshold for the position deviation of adjacent relevant peaks; If the amplitude of the current related peak exceeds the related peak threshold, the related results show a local downward trend, or the current related peak index deviation is not greater than the tolerance threshold for the position deviation of adjacent related peaks, then the next related peak is determined to be ready, the status of the next related peak is updated from zero to 1, and the current related peak value is recorded in the corresponding position of the peak list. Determine whether the count value of the relevant peak confirmation window counter has decreased to 0; If the count value of the correlation peak confirmation window counter decreases to 0, then it is determined whether the state of the next correlation peak is 1; otherwise, the count value of the correlation peak confirmation window counter is decremented by 1. If the state of the next relevant peak is 1, then the next relevant peak is determined to be valid within the relevant peak confirmation window, and the peak count is incremented by 1; otherwise, the peak count is cleared to zero.

13. The signal detection device according to claim 12, characterized in that, After determining that the first relevant peak has been detected, the previous relevant peak is updated with the current relevant peak value; the step of confirming the validity of the next relevant peak within the relevant peak confirmation window further includes: The current correlation peak deviation is obtained based on the current correlation peak and the previous correlation peak. Determine whether the current correlation peak deviation is not greater than the tolerance threshold for adjacent correlation peak deviations; Before determining that the next relevant peak is ready, it is also determined that the deviation of the current relevant peak is not greater than the tolerance threshold of the deviation of the adjacent relevant peak.

14. The signal detection device according to claim 1, characterized in that, The link measurement module is specifically used for: When the M-channel peak count of the symbol is 0, the M-channel command time slot power of the symbol is cleared to zero; and when the M-channel peak count of the symbol is not 0, the current symbol power of the symbol is added to the M-channel command time slot power of the symbol. When the S-channel peak count of the symbol is 0, the S-channel command time slot power of the symbol is cleared to zero; and when the S-channel peak count of the symbol is not 0, the current symbol power of the symbol is added to the S-channel command time slot power of the symbol.

15. The signal detection device according to claim 9, characterized in that, The code word judgment and confirmation module includes: The codeword search completion determination unit is used to determine whether the codeword search of the two paths has been completed based on the peak count and next correlation peak status in the peak information of the M-path and the peak count and next correlation peak status in the peak information of the S-path of the symbol, and to synchronize the codeword search process of the two paths. The codeword decision unit is used to make codeword decisions for the paths that have completed codeword searches based on the peak polarity in the corresponding peak list; The co-channel interference determination unit is used to determine the co-channel interference of M-channel and S-channel when both M-channel codeword decision results and S-channel codeword decision results are valid and different, based on the M-channel metric value, S-channel metric value, symbol power, M-channel instruction time slot power and S-channel instruction time slot power of each symbol, so as to determine the path with co-channel interference and set the codeword decision result of the path with co-channel interference to invalid. The decision result confirmation output unit is used to obtain the target instruction based on the validity of the decision results of the two codewords.

16. The signal detection device according to claim 15, characterized in that, The codeword search completion determination unit is specifically used for: When the peak count of one of the M-path and S-path of the symbol reaches a preset counting threshold, the peak count of the other reaches the preset counting threshold minus 1, and the next relevant peak state of the other is 1, the peak count of the other is incremented by 1, and the next relevant peak state of the other is cleared to zero; and When the M-way peak count of the symbol reaches the preset count threshold, it is determined that the M-way codeword search of the symbol has been completed; When the S-channel peak count of the symbol reaches the preset counting threshold, it is determined that the S-channel codeword search of the symbol has been completed.

17. The signal detection device according to claim 15, characterized in that, The code word decision unit is specifically used for: When the search for the M-way codewords of the symbol is completed, the decision result of the M-way codewords is determined to be valid. The M-way codewords corresponding to the peaks with positive polarity in the M-way peak list of the symbol are determined to be logical codewords 1, and the M-way codewords corresponding to the peaks with negative polarity are determined to be logical codewords 0. All the obtained M-way codewords are then converted into M-way instruction messages. When the S-way codeword search of the symbol is completed, the S-way codeword decision result is determined to be valid. The S-way codewords corresponding to peaks with positive peak polarity in the S-way peak list of the symbol are determined to be logical codewords 0, and the S-way codewords corresponding to peaks with negative peak polarity are determined to be logical codewords 1. All obtained S-way codewords are then converted into S-way instruction messages.

18. The signal detection device according to claim 17, characterized in that, The co-channel interference determination unit is specifically used for: When the M-channel instruction message and S-channel instruction message of the symbol are equal, or when one of the M-channel codeword decision result and the S-channel codeword decision result of the symbol is valid, it is determined that no co-channel interference determination is required. When both the M-way codeword decision result and the S-way codeword decision result of the symbol are valid, and the M-way instruction message and the S-way instruction message of the symbol are not equal, the M-way instruction message and the S-way instruction message of the symbol are converted into the average power of one symbol according to the number of symbols corresponding to the duration of the instruction time slot, so as to obtain the M-way average power and the S-way average power. If the symbol power of the symbol is greater than the product of the average power of the M channels and the interference power threshold, and the symbol power of the symbol is greater than the product of the average power of the S channels and the interference power threshold, then interference is determined to exist. When the product of the M-channel metric value and the interference path threshold of the symbol is greater than the S-channel metric value, it is determined that the M-channel is interfered with, and the decision result of the M-channel codeword is set to invalid. Similarly, when the product of the S-channel metric value and the interference path threshold of the symbol is greater than the M-channel metric value, it is determined that the S-channel is interfered with, and the decision result of the S-channel codeword is set to invalid. Herein, both the interference power threshold and the interference path threshold are less than 1.

19. The signal detection device according to claim 18, characterized in that, The judgment result confirmation output unit is specifically used for: When both codeword judgment results are valid and the instruction messages are equal, either of the two instruction messages shall be taken as the target instruction. If one of the two codeword decision results is valid, the instruction message in the valid codeword decision result shall be used as the target instruction; If both codeword decisions are invalid, an error is determined and signal detection is triggered again.

20. The signal detection device according to claim 2, characterized in that, The codeword reference sequence is obtained by repeating each element in the preset codeword sequence a preset number of times.

21. The signal detection device according to claim 1, characterized in that, The device further includes: An analog front-end processing module is connected before the demodulation and symbol decision module to perform at least analog-to-digital conversion on the received signal to obtain a digital signal.

22. The signal detection device according to claim 21, characterized in that, The simulated front-end processing module includes: An analog filtering unit is used to filter the received signal; The power amplifier unit is used to amplify the power of the filtered signal. The analog-to-digital conversion unit is used to perform analog-to-digital conversion on the power-amplified signal according to a preset sampling rate to obtain a digital signal.

23. The signal detection device according to claim 22, characterized in that, The simulation front-end processing module also includes: A gain control unit is used to adjust the gain of the power amplifier unit according to the power of the target digital signal.

24. The signal detection device according to claim 21, characterized in that, The device further includes: A digital front-end processing module is connected between the analog front-end processing module and the demodulation and symbol decision module. It is used to filter and downsample the digital signal and transmit the processed digital signal to the demodulation and symbol decision module. The downsampled sampling rate is an integer multiple of the fundamental frequency of the modulation frequency used by the received signal.

25. A receiver, characterized in that, include: The signal detection device according to any one of claims 1-24.

26. A signal detection method, characterized in that, include: The target digital signal is grouped to obtain multiple symbols. Coherent demodulation and symbol decision are performed on the multiple symbols respectively to obtain the M-way metric value, S-way metric value, symbol power, M-way symbol decision result and S-way symbol decision result for each symbol. The codeword reference sequence is correlated with the M-way symbol decision results of the plurality of symbols, and correlation peak detection is performed on each correlation result to obtain the M-way peak information of each symbol. The codeword reference sequence is also correlated with the S-way symbol decision results of the plurality of symbols, and correlation peak detection is performed on each correlation result to obtain the S-way peak information of each symbol. The M-way command time slot power of a symbol is obtained based on the symbol power of each symbol and the M-way peak count in the M-way peak information, and the S-way command time slot power of a symbol is obtained based on the symbol power of each symbol and the S-way peak count in the S-way peak information. Codeword decisions are made based on the M-channel peak information and S-channel peak information of each symbol to obtain M-channel codeword decision results and S-channel codeword decision results. Co-channel interference is determined based on the M-channel metric value, S-channel metric value, symbol power, M-channel command time slot power and S-channel command time slot power of each symbol. Finally, the target command is obtained based on the co-channel interference determination results, M-channel codeword decision results and S-channel codeword decision results of each symbol.

27. The signal detection method according to claim 26, characterized in that, Before grouping the target digital signal into multiple symbols, the method further includes: The target digital signal is subjected to frequency selective filtering.

28. The signal detection method according to claim 26, characterized in that, Peak information also includes a list of peaks and the status of the next relevant peak; For the k-th symbol, the correlation peak detection process includes: Compare the magnitude of the correlation result of the k-th symbol with the magnitude of the correlation peak; If the magnitude of the correlation result is greater than the magnitude of the correlation peak, then the magnitude of the correlation peak is updated to the magnitude of the correlation result, and the state of the next correlation peak is cleared to zero. Then, correlation peak detection is performed based on the peak count. Otherwise, correlation peak detection is performed directly based on the peak count. The step of detecting relevant peaks based on peak counts includes: When the peak count is 0, the first peak is detected, and after the first related peak is detected, the peak count and peak list are updated, the status of the next related peak is cleared, and a related peak confirmation window is set. When the peak count is greater than 0, the validity of the next related peak is confirmed in the related peak confirmation window, and the peak count, peak list and the status of the next related peak are updated. When the peak count reaches the pre-designed value, it is confirmed that the detection of the relevant peak of the k-th symbol is complete.

29. The signal detection method according to claim 28, characterized in that, The first peak detection includes: Determine whether the amplitude of the relevant peak exceeds the relevant peak threshold, and whether the relevant results show a local downward trend; If the amplitude of the correlation peak exceeds the correlation peak threshold and the correlation result shows a local downward trend, then the first correlation peak is detected. The updating of peak counts and peak lists includes: Increment the peak count by 1 and record the current relevant peak in the first position of the peak list.

30. The signal detection method according to claim 28, characterized in that, The setting of the relevant peak confirmation window includes: Set the initial value of the correlation peak confirmation window counter to the sum of the codeword length and the allowable deviation of the correlation peak index.

31. The signal detection method according to claim 29, characterized in that, After determining that the first relevant peak has been detected, the previous valid relevant peak index is updated with the current relevant peak index, and the expected relevant peak index is updated according to the previous valid relevant peak index and the codeword length; the validity confirmation of the next relevant peak within the relevant peak confirmation window, and the updating of the peak count, peak list and next relevant peak status, include: The current correlation peak index deviation is obtained based on the expected correlation peak index and the current correlation peak index. Determine whether the amplitude of the current relevant peak exceeds the relevant peak threshold, whether the relevant results show a local downward trend, and whether the current relevant peak index deviation is not greater than the tolerance threshold for the position deviation of adjacent relevant peaks; If the amplitude of the current related peak exceeds the related peak threshold, the related results show a local downward trend, or the current related peak index deviation is not greater than the tolerance threshold for the position deviation of adjacent related peaks, then the next related peak is determined to be ready, the status of the next related peak is updated from 0 to 1, and the current related peak value is recorded in the corresponding position of the peak list. Determine whether the count value of the relevant peak confirmation window counter has decreased to 0; If the count value of the correlation peak confirmation window counter decreases to 0, then it is determined whether the state of the next correlation peak is 1; otherwise, the count value of the correlation peak confirmation window counter is decremented by 1. If the state of the next relevant peak is 1, then the next relevant peak is determined to be valid within the relevant peak confirmation window, and the peak count is incremented by 1; otherwise, the peak count is cleared to zero.

32. The signal detection method according to claim 31, characterized in that, After determining that the first relevant peak has been detected, the previous relevant peak is updated with the current relevant peak value; the step of confirming the validity of the next relevant peak within the relevant peak confirmation window further includes: The current correlation peak deviation is obtained based on the current correlation peak and the previous correlation peak. Determine whether the current correlation peak deviation is not greater than the tolerance threshold for adjacent correlation peak deviations; Before determining that the next relevant peak is ready, it is also determined that the deviation of the current relevant peak is not greater than the tolerance threshold of the deviation of the adjacent relevant peak.

33. The signal detection method according to claim 28, characterized in that, The step of performing codeword decision based on the M-channel peak information and S-channel peak information of each symbol to obtain M-channel codeword decision results and S-channel codeword decision results, and performing co-channel interference determination on the M-channel and S-channel based on the M-channel metric value, S-channel metric value, symbol power, M-channel command time slot power, and S-channel command time slot power of each symbol, and obtaining the target command based on the co-channel interference determination result, the M-channel codeword decision result, and the S-channel codeword decision result of each symbol, includes: Based on the peak count and next correlation peak status in the M-path peak information of the symbol and the peak count and next correlation peak status in the S-path peak information, determine whether the two-path codeword search has been completed, and synchronize the codeword search process of the two paths. For paths where codeword search has been completed, codeword determination is performed based on the peak polarity in the corresponding peak list; When the decision results of the M-way codeword and the decision results of the S-way codeword are both valid and different, the M-way and S-way co-channel interference is determined based on the M-way metric value, S-way metric value, symbol power, M-way instruction time slot power and S-way instruction time slot power of each symbol, so as to determine the path with co-channel interference, and set the codeword decision result of the path with co-channel interference to invalid. The target instruction is obtained based on the validity of the two codeword judgment results.

34. The signal detection method according to claim 33, characterized in that, The step of determining whether the codeword search of the two paths has been completed based on the peak count and next correlation peak state in the peak information of the M-path and the peak count and next correlation peak state in the peak information of the S-path, and synchronizing the codeword search process of the two paths, includes: When the peak count of one of the M-path and S-path of the symbol reaches a preset counting threshold, the peak count of the other reaches the preset counting threshold minus 1, and the next relevant peak state of the other is 1, the peak count of the other is incremented by 1, and the next relevant peak state of the other is cleared to zero; and When the M-way peak count of the symbol reaches the preset counting threshold, it is determined that the M-way codeword search of the symbol has been completed; when the S-way peak count of the symbol reaches the preset counting threshold, it is determined that the S-way codeword search of the symbol has been completed.

35. The signal detection method according to claim 33, characterized in that, The step of determining the codewords for the paths for which codeword searches have been completed based on the peak polarity in the corresponding peak list includes: When the search for the M-way codewords of the symbol is completed, the decision result of the M-way codewords is determined to be valid. The M-way codewords corresponding to the peaks with positive polarity in the M-way peak list of the symbol are determined to be logical codewords 1, and the M-way codewords corresponding to the peaks with negative polarity are determined to be logical codewords 0. All the obtained M-way codewords are then converted into M-way instruction messages. When the S-way codeword search of the symbol is completed, the S-way codeword decision result is determined to be valid. The S-way codewords corresponding to peaks with positive peak polarity in the S-way peak list of the symbol are determined to be logical codewords 0, and the S-way codewords corresponding to peaks with negative peak polarity are determined to be logical codewords 1. All obtained S-way codewords are then converted into S-way instruction messages.

36. The signal detection method according to claim 33, characterized in that, The process for determining co-channel interference includes: When the M-channel instruction message and S-channel instruction message of the symbol are equal, or when one of the M-channel codeword decision result and the S-channel codeword decision result of the symbol is valid, it is determined that no co-channel interference determination is required. When both the M-way codeword decision result and the S-way codeword decision result of the symbol are valid, and the M-way instruction message and the S-way instruction message of the symbol are not equal, the M-way instruction message and the S-way instruction message of the symbol are converted into the average power of one symbol according to the number of symbols corresponding to the duration of the instruction time slot, so as to obtain the M-way average power and the S-way average power. If the symbol power of the symbol is greater than the product of the average power of the M channels and the interference power threshold, and the symbol power of the symbol is greater than the product of the average power of the S channels and the interference power threshold, then interference is determined to exist. When the product of the M-channel metric value and the interference path threshold of the symbol is greater than the S-channel metric value, it is determined that the M-channel is interfered with, and the decision result of the M-channel codeword is set to invalid. Similarly, when the product of the S-channel metric value and the interference path threshold of the symbol is greater than the M-channel metric value, it is determined that the S-channel is interfered with, and the decision result of the S-channel codeword is set to invalid. Herein, both the interference power threshold and the interference path threshold are less than 1.

37. The signal detection method according to claim 33, characterized in that, The process of obtaining the target instruction based on the validity of the two codeword decision results includes: When both codeword judgment results are valid and the instruction messages are equal, either of the two instruction messages shall be taken as the target instruction. If one of the two codeword decision results is valid, the instruction message in the valid codeword decision result shall be used as the target instruction; If both codeword decisions are invalid, an error is determined and signal detection is triggered again.

38. A chip comprising a memory, a processor, and a computer program stored in the memory, characterized in that, When the computer program is executed by the processor, it implements the signal detection method according to any one of claims 26-37.

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