Non-cooperative measurement and control signal parameter identification and analysis method and device and related equipment

Abstract

The application provides a non-cooperative measurement and control signal parameter identification and analysis method and device and related equipment, the method comprising: modulating and identifying a non-cooperative measurement and control signal and demodulating to obtain a demodulated bit stream; decoding the demodulated bit stream to obtain a decoded bit stream; analyzing the decoded bit stream according to a frame structure of the CCSDS specification to obtain a plurality of transmission frame identifiers, each transmission frame identifier comprising at least a spacecraft identifier and a virtual channel identifier; and obtaining APID data in the decoded bit stream based on each transmission frame identifier and a packet header structure of the CCSDS specification. The method provided by the application can automatically debug and analyze non-cooperative measurement and control signals, thereby reducing operation and maintenance costs.

Description

Technical Field

[0001] This invention relates to the field of signal processing technology, and in particular to a method, apparatus and related equipment for identifying and analyzing non-cooperative measurement and control signal parameters. Background Technology

[0002] With the rapid development of aerospace technology, the value of telemetry, tracking, and command (TT&C) systems in both military and civilian fields is becoming increasingly prominent. Against this backdrop, signal sensing and protocol parsing technologies for non-cooperative communication scenarios have become a key area of ​​research in the industry. This technology can significantly improve the sensing accuracy and resource utilization of spectrum monitoring and cognitive radio systems. Especially in the military field, the identification and protocol parsing of non-cooperative signals has significant strategic value.

[0003] Existing technologies lack full-process automation capabilities. From signal detection, parameter tuning, demodulation strategy adjustment to data analysis, all processes require manual operation by professional technicians. On the one hand, manual intervention is prone to operational errors and response delays, making it unsuitable for scenarios such as sudden signals and real-time monitoring. On the other hand, in scenarios such as unattended monitoring stations and large-scale spectrum monitoring networks, manual operation and maintenance require significant manpower and are difficult to achieve 24-hour continuous and stable operation, further limiting the application scenarios and large-scale deployment capabilities of existing technologies. Summary of the Invention

[0004] In view of this, the present invention provides a method, apparatus and related equipment for identifying and parsing non-cooperative measurement and control signal parameters. Through this method, the debugging and parsing of non-cooperative measurement and control signals can be automatically realized, reducing operation and maintenance costs.

[0005] A method for identifying and parsing non-cooperative measurement and control signal parameters, comprising:

[0006] Modulation identification and demodulation are performed on non-cooperative measurement and control signals to obtain a demodulated bit stream;

[0007] The demodulated bitstream is decoded to obtain the decoded bitstream;

[0008] The decoded bitstream is parsed according to the frame structure of the CCSDS specification to obtain multiple transmission frame identifiers, each of which includes at least a spacecraft identifier and a virtual channel identifier.

[0009] Based on the identifiers of each transmission frame and the header structure of the CCSDS specification, the APID data in the decoded bitstream is obtained.

[0010] Optionally, the above method may further include:

[0011] Search for carrier frequencies, obtain the main carrier that currently meets the specifications of the measurement and control signal, and lock and track the main carrier. The locked main carrier is a non-cooperative measurement and control signal.

[0012] Optionally, in the above method, the modulation identification and demodulation of the non-cooperative measurement and control signal to obtain the demodulated bit stream includes:

[0013] Obtain the subcarrier in the primary carrier;

[0014] Identify the first modulation scheme of the subcarrier, and demodulate the subcarrier based on the first modulation scheme to obtain a digital signal;

[0015] The digital signal is subjected to multiple power spectrum analysis to obtain the center frequency, symbol rate, and second modulation scheme;

[0016] Based on the center frequency and the symbol rate, the digital signal is sequentially subjected to DDC resampling, timing synchronization and carrier synchronization operations to obtain the processed digital signal;

[0017] The processed digital signal is demodulated based on the second modulation method to obtain a demodulated bit stream.

[0018] Optionally, in the above method, decoding the demodulated bitstream to obtain the decoded bitstream includes:

[0019] Obtain a set of synchronization codes that conform to the CCSDS specification;

[0020] Search for a synchronization code related to the demodulated bitstream in the set of synchronization codes, and determine the encoding type and encoding parameters of the demodulated bitstream based on the search results;

[0021] The demodulated bitstream is decoded according to the encoding type and encoding parameters to obtain the decoded bitstream.

[0022] Optionally, in the above method, obtaining the set of synchronization codes conforming to the CCSDS specification includes:

[0023] Verify whether the demodulated bitstream contains convolutional codes related to the CCSDS specification;

[0024] If the demodulated bitstream contains the convolutional code, obtain a set of synchronization codes that conform to the CCSDS specification and are associated with the convolutional code;

[0025] If the demodulated bitstream does not contain the convolutional code, obtain the set of all synchronization codes conforming to the CCSDS specification.

[0026] Optionally, in the above method, the step of checking whether the demodulated bitstream contains convolutional codes related to the CCSDS specification includes:

[0027] Generate multiple code rate parity-check matrices corresponding to the convolutional code;

[0028] The demodulated bitstream is verified by applying the parity check matrix of each bit rate to obtain the pass rate of each bit rate;

[0029] Check whether the maximum pass rate exceeds the preset verification threshold;

[0030] If the maximum pass rate exceeds the verification threshold, it is determined that the demodulated bitstream contains the convolutional code;

[0031] If the maximum pass rate does not exceed the verification threshold, it is determined that the demodulated bitstream does not contain the convolutional code.

[0032] Optionally, in the above method, obtaining the APID data in the decoded bitstream based on each of the transmission frame identifiers and the packet header structure of the CCSDS specification includes:

[0033] Based on the identifiers of each transmission frame, determine the header position in the decoded bitstream that is related to the header structure;

[0034] Based on the packet header position, obtain the APID information of each bit in the decoded bit stream and the packet header length;

[0035] The APID information is concatenated based on the header length to obtain APID data.

[0036] A non-cooperative measurement and control signal parameter identification and analysis device includes:

[0037] The demodulation unit is used to perform modulation identification and demodulation on non-cooperative measurement and control signals to obtain a demodulated bit stream.

[0038] The decoding unit is used to decode the demodulated bitstream to obtain a decoded bitstream;

[0039] The parsing unit is used to parse the decoded bit stream according to the frame structure of the CCSDS specification to obtain multiple transmission frame identifiers, each of which includes at least a spacecraft identifier and a virtual channel identifier.

[0040] A data processing unit is used to obtain APID data in the decoded bitstream based on the identifiers of each transmission frame and the header structure of the CCSDS specification. A storage medium includes stored instructions, wherein, when the instructions are executed, the device containing the storage medium is controlled to perform the aforementioned non-cooperative measurement and control signal parameter identification and parsing method.

[0041] A storage medium comprising stored instructions, wherein, when the instructions are executed, the device containing the storage medium is controlled to perform the aforementioned non-cooperative measurement and control signal parameter identification and parsing method.

[0042] An electronic device includes a memory and one or more instructions, wherein one or more instructions are stored in the memory and configured to be executed by one or more processors. The method for identifying and parsing non-cooperative measurement and control signal parameters described above.

[0043] Compared with the prior art, the present invention has the following advantages:

[0044] This invention provides a method for identifying and parsing parameters of non-cooperative telemetry and control signals, comprising: modulating and demodulating the non-cooperative telemetry and control signals to obtain a demodulated bitstream; decoding the demodulated bitstream to obtain a decoded bitstream; parsing the decoded bitstream according to the frame structure of the CCSDS specification to obtain multiple transmission frame identifiers, each transmission frame identifier including at least a spacecraft identifier and a virtual channel identifier; and obtaining APID data in the decoded bitstream based on each transmission frame identifier and the packet header structure of the CCSDS specification. Applying the method provided by this invention can achieve automatic debugging and parsing of non-cooperative telemetry and control signals, reducing operation and maintenance costs. Attached Figure Description

[0045] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the provided drawings without creative effort.

[0046] Figure 1 A flowchart illustrating a method for identifying and parsing non-cooperative measurement and control signal parameters provided in an embodiment of the present invention;

[0047] Figure 2 This is another flowchart of a non-cooperative measurement and control signal parameter identification and parsing method provided in an embodiment of the present invention;

[0048] Figure 3 This is a schematic diagram of synchronization code search and decoding provided in an embodiment of the present invention;

[0049] Figure 4 This is a schematic diagram of convolutional code recognition provided in an embodiment of the present invention;

[0050] Figure 5This is a schematic diagram of the frame structure of the measurement and control signal provided in an embodiment of the present invention;

[0051] Figure 6 This is a schematic diagram of the header structure of the measurement and control signal provided in an embodiment of the present invention;

[0052] Figure 7 This is a structural diagram of a non-cooperative measurement and control signal parameter identification and analysis device provided in an embodiment of the present invention;

[0053] Figure 8 This is a schematic diagram of an electronic device structure provided in an embodiment of the present invention. Detailed Implementation

[0054] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0055] In this application, relational terms such as "first" and "second" are used merely to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. The terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0056] This invention can be used in a wide variety of general-purpose or special-purpose computing environments or configurations. For example: personal computers, server computers, handheld or portable devices, tablet devices, multiprocessor devices, distributed computing environments including any of the above devices, etc.

[0057] This invention provides a method for identifying and parsing non-cooperative measurement and control signal parameters. The method is applied to a processor, and its flowchart is shown below. Figure 1 As shown, it specifically includes:

[0058] S1: Modulate, identify, and demodulate non-cooperative measurement and control signals to obtain a demodulated bit stream;

[0059] S2: Decode the demodulated bitstream to obtain the decoded bitstream;

[0060] S3: Parse and decode the bit stream according to the frame structure of the CCSDS specification to obtain multiple transmission frame identifiers. Each transmission frame identifier includes at least the spacecraft identifier and the virtual channel identifier.

[0061] S4: Based on the identifiers of each transmission frame and the header structure of the CCSDS specification, obtain the APID data in the decoded bitstream.

[0062] Based on the steps S1-S5 above, the following specific explanations are provided.

[0063] S1: Modulate, identify, and demodulate non-cooperative measurement and control signals to obtain a demodulated bit stream.

[0064] In this invention, non-cooperative telemetry and control signals are captured by signal tracking, and then modulated, identified, and demodulated. During the capture of non-cooperative telemetry and control signals, a carrier frequency is searched within a preset frequency search range to obtain the main carrier that currently conforms to the telemetry and control signal specifications, and the non-cooperative telemetry and control signals are obtained from the main carrier.

[0065] Specifically, the method for obtaining non-cooperative telemetry and control (TT&C) signals on the main carrier is as follows: search for the carrier frequency, obtain the main carrier that currently conforms to the TT&C signal specifications, and lock and track the main carrier. The locked main carrier is the currently captured non-cooperative TT&C signal. During the carrier frequency search, the CCSDS (the consultative committee for space data system) specifications can be used as the TT&C signal specifications for signal search to avoid the searched signal being a broadcast signal, noise, or other interference signal. In addition, to avoid the loss of the searched main carrier signal, a phase-locked loop (PLL) can be used to track the signal and achieve frequency synchronization with the searched signal, thereby converting the signal from radio frequency to a fixed intermediate frequency (IF) or baseband signal.

[0066] After the primary carrier is located and locked onto, since it is a non-cooperative telemetry and control signal, it needs to be modulated, identified, and demodulated to obtain the corresponding bitstream data. In this invention, the specific process of modulating, identifying, and demodulating the non-cooperative telemetry and control signal to obtain the demodulated bitstream is as follows: Figure 2 As shown, it specifically includes:

[0067] S11: Obtain the subcarrier in the primary carrier.

[0068] Step S11 involves stripping the outer modulation of the main carrier, identifying the subcarrier position on the locked main carrier, and stripping the subcarrier from the main carrier.

[0069] S12: Identify the first modulation scheme of the subcarrier, and demodulate the subcarrier based on the first modulation scheme to obtain a digital signal.

[0070] During the generation of the primary carrier, the original data is modulated into a subcarrier as a digital signal, and then modulated back onto the primary carrier. To recover the data carried in the subcarrier, the first modulation scheme of the subcarrier is first identified, and then demodulated according to the first modulation scheme to obtain the digital signal.

[0071] The first modulation scheme of the subcarrier is one of AM (Amplitude Modulation), FM (Frequency Modulation), and PM (Phase Modulation). During the identification process, various modulation schemes are tried in turn to determine the first modulation scheme, and demodulation processing is performed according to the first modulation scheme to output a digital signal with the outer modulation pattern demodulated.

[0072] Since the detected signal is an unknown non-cooperative signal, the subcarrier can be demodulated using AM, FM, and PM methods through "blind demodulation" to determine the modulation scheme of the subcarrier.

[0073] It should be noted that the demodulation process of the subcarrier according to the first modulation method in S12 of the present invention is not the final modulation identification and demodulation of the non-cooperative measurement and control signal, but only an intermediate process for processing the residual carrier in the subcarrier. Through the demodulation process in S12, a clean digital signal can be obtained, so as to facilitate further processing of the signal in subsequent S13-S15.

[0074] S13: Perform multiple spectrum analysis on the digital signal to obtain the center frequency, symbol rate, and second modulation scheme.

[0075] Digital signals undergo nonlinear transformation through multiple-stage spectral analysis (e.g., quadratic or quartic spectral analysis), resulting in discrete spectral lines on the signal spectrum. The positions of these lines directly correspond to the symbol rate and modulation type characteristics (e.g., the quadratic spectrum of BPSK will show lines at twice the carrier frequency). After multiple-stage spectral analysis, three core parameters of the signal are identified: center frequency, symbol rate, and second modulation scheme. The center frequency determines the carrier frequency of the symbols, the symbol rate determines the transmission rate of symbols per second, and the second modulation scheme, which differs from the first modulation scheme, determines the signal's modulation pattern. Corresponding modulation schemes include BPSK (Binary Phase Shift Keying) and QPSK (Quadrature Phase Shift Keying).

[0076] S14: Based on the center frequency and symbol rate, perform DDC resampling, timing synchronization and carrier synchronization operations on the digital signal in sequence to obtain the processed digital signal.

[0077] For the DDC resampling process, the digital signal is converted to baseband based on the center frequency and symbol rate, and the sampling rate is adjusted to match the symbol rate in order to remove redundant sampling points, so that the signal retains only the key information of each symbol, further reducing the burden of subsequent calculations.

[0078] For the timing synchronization process, after DDC resampling, the optimal sampling time for each symbol is found (e.g., at the highest point or center point of the symbol waveform) to eliminate clock skew and obtain a stable waveform.

[0079] For the carrier synchronization process, even if the signal has been resampled by DDC, there may still be a tiny frequency offset (frequency deviation) and phase jitter remaining in the signal. Therefore, it is necessary to further eliminate the residual carrier frequency offset and phase shift in the signal to make the signal phase completely locked.

[0080] S15: Demodulate the processed digital signal based on the second modulation method to obtain a demodulated bit stream.

[0081] Based on the second modulation scheme obtained from step S13 above, the digital signal that has been resampled by DDC, synchronized by timing and carrier is demodulated, that is, the symbols in the signal are converted into corresponding bit values ​​to obtain the demodulated bit stream.

[0082] In the method provided by the embodiments of the present invention, non-cooperative measurement and control signals are captured by searching the carrier frequency, and the signals are modulated, identified and demodulated. During the modulation, identification and demodulation process, the signals are resampled, timed and synchronized and carrier synchronized to obtain more stable waveform signals, ensuring that the demodulation obtains accurate bit stream data.

[0083] S2: Decode the demodulated bitstream to obtain the decoded bitstream.

[0084] Specifically, the demodulated bitstream is decoded according to the encoding rules of the CCSDS specification to obtain the decoded bitstream.

[0085] It should be noted that after the non-cooperative telemetry and control signal undergoes the process described in S1, the output demodulated bit stream is a stream of data consisting of 0s and 1s. Since the CCSDS specification is a standard encoding recommended by the International Space Data System Advisory Committee, the demodulated bit stream must be decoded according to this specification to ensure that the output stream conforms to the CCSDS specification.

[0086] During the decoding of the demodulated bitstream, a set of synchronization codes conforming to the CCSDS specification is obtained. The synchronization codes related to the demodulated bitstream are searched in the set of synchronization codes, and the encoding type and encoding parameters of the demodulated bitstream are determined according to the search results. The demodulated bitstream is then decoded according to the encoding type and encoding parameters to obtain the decoded bitstream.

[0087] The synchronization code set contains various synchronization codes, including BCH code (Bose-Chaudhuri-Hocquenghem code), RS code (Reed-Solomon code), Turbo code, and LDPC code (Low-Density Parity-Check code).

[0088] For example, the RS code is 0x1ACFFC1D, the BCH code is 0xEB90, the Turbo code with a code rate of 1 / 2, 2 / 3, or 4 / 5 is 0x034776C7272895B0, the Turbo code with a code rate of 1 / 3 is 0x25D5C0CE8990F6C9461BF79C, the Turbo code with a code rate of 1 / 4 is 0x034776C7272895B0FCB88938D8D76A4F, the Turbo code with a code rate of 1 / 6 is 0x25D5C0CE8990F6C9461BF79CDA2A3F31766F0936B9E40863, and the LDPC code is 0x25D5C0CE8990F6C9461BF79C.

[0089] The process of searching for a synchronization code associated with the demodulated bitstream involves detecting whether the demodulated bitstream contains a bit sequence identical to any given synchronization code. A "window length" can be set, equal to the length of the longest synchronization code in the set (e.g., CCSDS synchronization codes are mostly 32 bits, so the window length is set to 32 bits). This window is then moved bit-by-bit across the demodulated bitstream, truncating one bit at a time. The truncated bit sequence is compared with each synchronization code. If the bit sequence contains any synchronization code, a synchronization code associated with the demodulated bitstream has been successfully found, and the search result is obtained. This search result is the successfully found synchronization code associated with the demodulated bitstream. Based on the found synchronization code, the encoding type and encoding parameters are determined. A decoder associated with this encoding type and parameters can then be called to decode the demodulated bitstream, obtaining the decoded bitstream.

[0090] Specifically, each synchronization code can be saved to a preset database, and the demodulated bitstream can be input into this database to search for the synchronization code, such as... Figure 3 As shown, the code searches for whether it conforms to BCH code, RS code, Turbo code, and LDPC code. If it conforms to BCH code, it is decoded according to the encoding type and parameters of BCH code; if it conforms to RS code, it is decoded according to the encoding type and parameters of RS code; if it conforms to Turbo code, it is decoded according to the encoding type and parameters of Turbo code; and if it conforms to LDPC code, it is decoded according to the encoding type and parameters of LDPC code.

[0091] Since (2, 1, 6) convolutional codes are typically used in the CCSDS specification, after obtaining the demodulated bitstream, it is necessary to identify whether it contains convolutional codes related to the CCSDS specification; that is, to identify whether the demodulated bitstream contains (2, 1, 6) convolutional codes. If the demodulated bitstream contains convolutional codes, obtain the set of synchronization codes that conform to the CCSDS specification and are associated with the convolutional codes; if the demodulated bitstream does not contain convolutional codes, obtain the set of all synchronization codes that conform to the CCSDS specification.

[0092] Specifically, the process of identifying whether the demodulated bitstream contains convolutional codes is as follows: generate parity check matrices for multiple code rates corresponding to the convolutional codes related to the CCSDS specification; apply the parity check matrices for each code rate to check the demodulated bitstream and obtain the pass rate for each code rate; check whether the maximum pass rate exceeds a preset parity threshold; if the maximum pass rate exceeds the parity threshold, determine that the demodulated bitstream contains convolutional codes, otherwise the demodulated bitstream does not contain convolutional codes.

[0093] like Figure 4 As shown, for a (2, 1, 6) convolutional code, there are multiple code rate parity check matrices (such as...). Figure 4The 1 / 2 rate parity check (CD-MS) matrix, 2 / 3 rate CD-MS, ..., 7 / 8 rate CD-MS matrix are used to calculate the pass rate of each CD-MS matrix. The maximum pass rate is selected and compared with the parity threshold. If the maximum pass rate exceeds the parity threshold, it indicates that the demodulated bitstream contains the convolutional code. The demodulated bitstream is then decoded based on the convolutional code to obtain the decoded bitstream.

[0094] When the demodulated bitstream contains convolutional codes, a set of synchronization codes conforming to the CCSDS specification and associated with the convolutional codes is obtained. Based on the synchronization code set, a synchronization code search is performed on the demodulated bitstream. The encoding type and encoding parameters of the demodulated bitstream are determined according to the search results. The demodulated bitstream is then decoded according to the encoding type and encoding parameters to obtain the decoded bitstream. When the demodulated bitstream does not contain convolutional codes, a set of all synchronization codes conforming to the CCSDS specification is obtained. Based on the synchronization code set, a synchronization code search is performed on the demodulated bitstream. The encoding type and encoding parameters of the demodulated bitstream are determined according to the search results. The demodulated bitstream is then decoded according to the encoding type and encoding parameters to obtain the decoded bitstream.

[0095] In an optional embodiment, if the demodulated bitstream does not contain convolutional codes, decoding of the demodulated bitstream is not required; the subsequent processing steps S3-S4 described above can be performed directly based on the demodulated bitstream. Alternatively, if the demodulated bitstream does not contain convolutional codes, it can still be decoded to obtain a decoded bitstream, and the aforementioned steps S3-S4 can continue to be executed.

[0096] In this invention, the encoding parameters can be directly associated by matching synchronization codes, avoiding blindly using multiple decoding methods, thereby reducing computational complexity. When the demodulated bitstream contains convolutional codes, the matching range of synchronization codes can be further narrowed, improving decoding efficiency.

[0097] S3: Parse and decode the bitstream according to the frame structure of the CCSDS specification to obtain multiple transmission frame identifiers. Each transmission frame identifier includes at least a spacecraft identifier and a virtual channel identifier.

[0098] refer to Figure 5 , Figure 5 This is a schematic diagram of the measurement and control signal frame structure according to the CCSDS specification, including the main header and subheading of the transmission frame. Based on the frame structure, the transmission frame identifier (e.g., ...) is obtained. Figure 5 (The spacecraft identifier, virtual channel identifier, and operation control field flag are included). Based on the transmission frame identifier, each transmission frame in the decoded bit stream can be identified, and the start and end positions of each transmission frame can be determined.

[0099] S4: Based on the identifiers of each transmission frame and the header structure of the CCSDS specification, obtain the APID data in the decoded bitstream.

[0100] refer to Figure 6 , Figure 6 To conform to the CCSDS specification for the header structure of measurement and control signals, based on the transmission frame identifier obtained in S3 above, the start and end positions of the transmission frames in the decoded bitstream are determined to establish the header structure. Then, APID (Application Process Identifier) ​​information and packet data length are extracted according to the header indication. Since data may be split into multiple packets during transmission, after extracting multiple APID information from the header, the APID information of the same APID is concatenated according to the packet data length and the APIDs contained in each APID information to obtain multiple APID data.

[0101] Furthermore, after obtaining the APID data, the data can be distributed to different upper-layer application devices for processing based on the ID indicated in each APID data.

[0102] The method provided in this invention can automatically identify the modulation and encoding methods of non-cooperative measurement and control signals, perform demodulation and decoding, and automatically parse the subsequent protocols to finally obtain the APID data. The method provided by this invention has important strategic value for the analysis of non-cooperative measurement and control signals. Through automatic modulation and parsing, it can automatically analyze non-cooperative measurement and control signals without manual intervention, which can not only avoid operational errors but also reduce operation and maintenance costs.

[0103] and Figure 1 Corresponding to the method described above, this embodiment of the invention also provides a non-cooperative measurement and control signal parameter identification and analysis device, used for... Figure 1 In the specific implementation of the method, the non-cooperative measurement and control signal parameter identification and parsing device provided in this embodiment of the invention is applied to the processor, and its structural schematic diagram is shown below. Figure 7 As shown, it specifically includes:

[0104] The demodulation unit 701 is used to perform modulation identification and demodulation on non-cooperative measurement and control signals to obtain a demodulated bit stream.

[0105] Decoding unit 702 is used to decode the demodulated bit stream to obtain a decoded bit stream;

[0106] The parsing unit 703 is used to parse the decoded bit stream according to the frame structure of the CCSDS specification to obtain multiple transmission frame identifiers, each of which includes at least a spacecraft identifier and a virtual channel identifier.

[0107] The data processing unit 704 is used to obtain APID data in the decoded bitstream based on the identifiers of each transmission frame and the header structure of the CCSDS specification.

[0108] The apparatus provided in this embodiment of the invention further includes:

[0109] The signal search unit is used to search for carrier frequencies, obtain the main carrier that currently conforms to the specifications of the measurement and control signal, and lock and track the main carrier. The locked main carrier is a non-cooperative measurement and control signal.

[0110] In the apparatus provided in this embodiment of the invention, the demodulation unit 701 performs modulation identification and demodulation on non-cooperative measurement and control signals to obtain a demodulated bit stream, specifically used for:

[0111] Obtain the subcarrier in the primary carrier;

[0112] Identify the first modulation scheme of the subcarrier, and demodulate the subcarrier based on the first modulation scheme to obtain a digital signal;

[0113] The digital signal is subjected to multiple power spectrum analysis to obtain the center frequency, symbol rate, and second modulation scheme;

[0114] Based on the center frequency and the symbol rate, the digital signal is sequentially subjected to DDC resampling, timing synchronization and carrier synchronization operations to obtain the processed digital signal;

[0115] The processed digital signal is demodulated based on the second modulation method to obtain a demodulated bit stream.

[0116] In the apparatus provided in this embodiment of the invention, the decoding unit 702 decodes the demodulated bitstream to obtain a decoded bitstream, specifically for:

[0117] Obtain a set of synchronization codes that conform to the CCSDS specification;

[0118] Search for a synchronization code related to the demodulated bitstream in the set of synchronization codes, and determine the encoding type and encoding parameters of the demodulated bitstream based on the search results;

[0119] The demodulated bitstream is decoded according to the encoding type and encoding parameters to obtain the decoded bitstream.

[0120] In the apparatus provided in this embodiment of the invention, the decoding unit 702 acquires a set of synchronization codes conforming to the CCSDS specification, specifically for:

[0121] Verify whether the demodulated bitstream contains convolutional codes related to the CCSDS specification;

[0122] If the demodulated bitstream contains the convolutional code, obtain a set of synchronization codes that conform to the CCSDS specification and are associated with the convolutional code;

[0123] If the demodulated bitstream does not contain the convolutional code, obtain the set of all synchronization codes conforming to the CCSDS specification.

[0124] In the apparatus provided in this embodiment of the invention, the decoding unit 702 verifies whether the demodulated bitstream contains convolutional codes related to the CCSDS specification, specifically for:

[0125] Generate multiple code rate parity-check matrices corresponding to the convolutional code;

[0126] The demodulated bitstream is verified by applying the parity check matrix of each bit rate to obtain the pass rate of each bit rate;

[0127] Check whether the maximum pass rate exceeds the preset verification threshold;

[0128] If the maximum pass rate exceeds the verification threshold, it is determined that the demodulated bitstream contains the convolutional code;

[0129] If the maximum pass rate does not exceed the verification threshold, it is determined that the demodulated bitstream does not contain the convolutional code.

[0130] In the apparatus provided in this embodiment of the invention, the data processing unit 704 obtains APID data in the decoded bitstream based on each of the transmission frame identifiers and the packet header structure of the CCSDS specification, specifically for:

[0131] Based on the identifiers of each transmission frame, determine the header position in the decoded bitstream that is related to the header structure;

[0132] Based on the packet header position, obtain the APID information of each bit in the decoded bit stream and the packet header length;

[0133] The APID information is concatenated based on the header length to obtain APID data.

[0134] The specific working process of each unit and subunit in the non-cooperative measurement and control signal parameter identification and parsing device disclosed in the above embodiments of the present invention can be found in the corresponding content of the non-cooperative measurement and control signal parameter identification and parsing method disclosed in the above embodiments of the present invention, and will not be repeated here.

[0135] This invention also provides a storage medium, which includes stored instructions, wherein when the instructions are executed, the device containing the storage medium is controlled to perform the above-described non-cooperative measurement and control signal parameter identification and parsing method.

[0136] This invention also provides an electronic device, the structural schematic of which is shown below. Figure 8 As shown, it specifically includes a memory 801 and one or more instructions 802, wherein one or more instructions 802 are stored in the memory 801 and configured to be executed by one or more processors 803 to perform the following operations:

[0137] Modulation identification and demodulation are performed on non-cooperative measurement and control signals to obtain a demodulated bit stream;

[0138] The demodulated bitstream is decoded to obtain the decoded bitstream;

[0139] The decoded bitstream is parsed according to the frame structure of the CCSDS specification to obtain multiple transmission frame identifiers, each of which includes at least a spacecraft identifier and a virtual channel identifier.

[0140] Based on the identifiers of each transmission frame and the header structure of the CCSDS specification, the APID data in the decoded bitstream is obtained.

[0141] The various embodiments in this specification are described in a progressive manner. Similar or identical parts between embodiments can be referred to mutually. Each embodiment focuses on describing the differences from other embodiments. In particular, for system or system embodiments, since they are basically similar to method embodiments, the description is relatively simple, and relevant parts can be referred to the descriptions in the method embodiments. The systems and system embodiments described above are merely illustrative. The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the modules can be selected to achieve the purpose of this embodiment according to actual needs. Those skilled in the art can understand and implement this without creative effort.

[0142] Those skilled in the art will further recognize that the units and algorithm steps of the various examples described in connection with the embodiments disclosed herein can be implemented in electronic hardware, computer software, or a combination of both.

[0143] To clearly illustrate the interchangeability of hardware and software, the components and steps of each example have been generally described in terms of functionality above. Whether these functions are implemented in hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementations should not be considered beyond the scope of this invention.

[0144] The above description of the disclosed embodiments enables those skilled in the art to make or use the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A method for identifying and parsing non-cooperative measurement and control signal parameters, characterized in that, include: Modulation identification and demodulation are performed on non-cooperative measurement and control signals to obtain a demodulated bit stream; The non-cooperative telemetry and control signal is a signal of the main carrier locked through carrier frequency search; The demodulated bitstream is decoded to obtain the decoded bitstream; The decoded bitstream is parsed according to the frame structure of the CCSDS specification to obtain multiple transmission frame identifiers, each of which includes at least a spacecraft identifier and a virtual channel identifier. Based on the respective transmission frame identifiers and the packet header structure of the CCSDS specification, the APID data in the decoded bitstream is obtained; The modulation identification and demodulation of the non-cooperative measurement and control signal to obtain a demodulated bitstream includes: obtaining a subcarrier in the main carrier; identifying a first modulation scheme of the subcarrier and demodulating the subcarrier based on the first modulation scheme to obtain a digital signal; performing multiple power spectrum analysis on the digital signal to obtain a center frequency, symbol rate, and a second modulation scheme; performing DDC resampling, timing synchronization, and carrier synchronization operations on the digital signal sequentially based on the center frequency and the symbol rate to obtain a processed digital signal; and demodulating the processed digital signal based on the second modulation scheme to obtain a demodulated bitstream. Decoding the demodulated bitstream to obtain a decoded bitstream includes: acquiring a set of synchronization codes conforming to the CCSDS specification; searching the set of synchronization codes for a bit sequence related to the demodulated bitstream, and determining the encoding type and encoding parameters of the demodulated bitstream based on the search results; and calling a decoder related to the encoding type and encoding parameters to decode the demodulated bitstream to obtain a decoded bitstream.

2. The method according to claim 1, characterized in that, The method further includes: Search for carrier frequencies, obtain the main carrier that currently meets the specifications of the measurement and control signal, and lock and track the main carrier. The locked main carrier is a non-cooperative measurement and control signal.

3. The method according to claim 1, characterized in that, The process of obtaining a set of synchronization codes conforming to the CCSDS specification includes: Verify whether the demodulated bitstream contains convolutional codes related to the CCSDS specification; If the demodulated bitstream contains the convolutional code, obtain a set of synchronization codes that conform to the CCSDS specification and are associated with the convolutional code; If the demodulated bitstream does not contain the convolutional code, obtain the set of all synchronization codes conforming to the CCSDS specification.

4. The method according to claim 3, characterized in that, The step of verifying whether the demodulated bitstream contains convolutional codes related to the CCSDS specification includes: Generate multiple code rate parity-check matrices corresponding to the convolutional code; The demodulated bitstream is verified by applying the parity check matrix of each bit rate to obtain the pass rate of each bit rate; Check whether the maximum pass rate exceeds the preset verification threshold; If the maximum pass rate exceeds the verification threshold, it is determined that the demodulated bitstream contains the convolutional code; If the maximum pass rate does not exceed the verification threshold, it is determined that the demodulated bitstream does not contain the convolutional code.

5. The method according to claim 4, characterized in that, The process of obtaining APID data in the decoded bitstream based on the identifiers of each transmission frame and the header structure of the CCSDS specification includes: Based on the identifiers of each transmission frame, determine the header position in the decoded bitstream that is related to the header structure; Based on the packet header position, obtain the APID information of each bit in the decoded bit stream and the packet header length; The APID information is concatenated based on the header length to obtain APID data.

6. A device for identifying and analyzing non-cooperative measurement and control signal parameters, characterized in that, include: The demodulation unit is used to perform modulation identification and demodulation on non-cooperative measurement and control signals to obtain a demodulated bit stream. The non-cooperative telemetry and control signal is a signal of the main carrier locked through carrier frequency search; The decoding unit is used to decode the demodulated bitstream to obtain a decoded bitstream; The parsing unit is used to parse the decoded bit stream according to the frame structure of the CCSDS specification to obtain multiple transmission frame identifiers, each of which includes at least a spacecraft identifier and a virtual channel identifier. The data processing unit is used to obtain APID data in the decoded bitstream based on the identifier of each transmission frame and the header structure of the CCSDS specification. The parsing unit performs modulation identification and demodulation on the non-cooperative measurement and control signal to obtain a demodulated bitstream. Specifically, this includes: obtaining the subcarrier in the main carrier; identifying the first modulation scheme of the subcarrier and demodulating the subcarrier based on the first modulation scheme to obtain a digital signal; performing multiple power spectrum analysis on the digital signal to obtain the center frequency, symbol rate, and second modulation scheme; performing DDC resampling, timing synchronization, and carrier synchronization operations on the digital signal sequentially based on the center frequency and the symbol rate to obtain a processed digital signal; and demodulating the processed digital signal based on the second modulation scheme to obtain a demodulated bitstream. The decoding unit decodes the demodulated bitstream to obtain a decoded bitstream, specifically including: acquiring a set of synchronization codes conforming to the CCSDS specification; searching the set of synchronization codes for a bit sequence related to the demodulated bitstream, and determining the encoding type and encoding parameters of the demodulated bitstream based on the search results; and calling a decoder related to the encoding type and encoding parameters to decode the demodulated bitstream to obtain a decoded bitstream.

7. A storage medium, characterized in that, The storage medium includes stored instructions, wherein, when the instructions are executed, the device containing the storage medium is controlled to perform the non-cooperative measurement and control signal parameter identification and parsing method as described in any one of claims 1-5.

8. An electronic device, characterized in that, It includes a memory and one or more instructions, wherein one or more instructions are stored in the memory and configured to be executed by one or more processors to perform the non-cooperative measurement and control signal parameter identification and parsing method as described in any one of claims 1-5.

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