Radar communication integrated radiation source simulation system and method

Abstract

The invention discloses a radar communication integrated radiation source simulation system and method. The system comprises an upper computer control unit, a signal processing unit, an up-conversion unit and an antenna unit. An unknown radar or communication signal is analyzed by adopting a signal characteristic analysis method based on phase difference, whether the signal is a complex signal is judged, the waveform of the signal is stored and generated by adopting a DDWS technology aiming at the unknown complex signal, the waveform of the signal is directly generated by adopting a modulation module of a signal processing unit aiming at a conventional signal, and the waveform of the signal is directly generated by adopting a modulation module of a signal processing unit aiming at a known complex signal. The waveform of a fixed part in a signal is synthesized by adopting a DDWS technology, a modulation module of the signal processing unit is used for generating a non-fixed part, and the fixed part and the non-fixed part are combined according to a signal message format time sequence, so that the simulation of a complex signal is realized, and the requirement of current electronic countermeasure training on radar communication integrated radiation source simulation is met.

Description

TECHNICAL FIELD

[0001] The present application relates to a radiation source simulation system and method, in particular to a radar communication integrated radiation source simulation system and method, and belongs to the technical field of electronic countermeasure training environment simulation. BACKGROUND

[0002] In recent years, the demand for electronic countermeasure training environment simulation is increasing, and the importance of electronic countermeasure training equipment is also increasing. Radar simulator and communication simulator are devices that can simulate real radar and communication signals, and can provide real training environment and experimental research environment for electronic countermeasure for the army and electronic countermeasure researchers.

[0003] In order to simulate a real electronic countermeasure environment, the current electronic countermeasure simulation training usually adopts a radar signal simulator and a communication signal simulator at the same time, and each of them separately completes the simulation of the radar signal and the communication signal. The problems existing in this electromagnetic environment construction mode mainly include: 1. The deployment difficulty of the electronic countermeasure training system is increased; 2. The difficulty of adjusting the electronic countermeasure training scene is increased, which is not convenient for experimental research; 3. It is difficult to ensure the mutual synchronization between different devices, so the difficulty of complex electromagnetic environment simulation is greatly increased. In the prior art, the radar communication integration method and system based on subcarrier multiplexing OFDM disclosed in CN115051901B can solve the allocation problem of time, frequency and energy resources under the moving platform, but the waveform structure is still relatively fixed, which is difficult to adapt to the demand of complex electromagnetic environment, especially in the electronic countermeasure training scene which needs to simulate multiple system radars and communication signals, the flexibility is insufficient; for example, the radar communication integration system based on CE-OFDM disclosed in CN106249231B converts the communication data into a CE-OFDM symbol frame through QAM modulation and IFFT transformation, and is used to replace a single pulse in the pulse repetition period, so as to improve the data transmission rate and reduce the signal peak-to-average ratio. However, this scheme has limitations when processing complex radar signals (such as linear frequency modulation signal phase encoding signals), especially for signals with frequent waveform changes and severe phase jumps. In addition, although this system improves the data transmission efficiency, it does not fully consider the optimization of hardware resources, especially in terms of FPGA logic resource and memory resource consumption, which is still a large overhead, and is not conducive to the miniaturization and integration of the system. In addition, most of the existing communication simulation devices can only simulate typical digital modulation signals, and lack the ability to simulate complex data link communication signals. Moreover, the existing data link simulation method based on FPGA constructs each functional module according to the processing steps of the data link signal one by one and combines them into the simulation transmitting end of the data link. Different data links use different functional modules, which are difficult to reuse, and occupy a large amount of FPGA logic resources. Therefore, the traditional radiation source simulation method and device cannot meet the needs of the current electronic countermeasure training task. SUMMARY

[0004] The purpose of the present application is to provide a radar communication integrated radiation source simulation system and method to solve at least one of the above technical problems. Based on the software radio platform of DSP+FPGA+DAC, the radar communication integrated design concept is adopted, which has the function of simulating multiple system target signals, can realize the switching between multiple target signal systems, and can complete the simulation of multiple complex radar and communication signal radiation sources.

[0005] The present application achieves the above-mentioned purpose through the following technical solutions: a radar communication integrated radiation source simulation system, the radiation source simulation system comprising:

[0006] The host computer control unit is responsible for sending control instructions to the signal processing unit and receiving its response information;

[0007] The signal processing unit adopts the architecture of a DSP module, a FPGA module and a DA module;

[0008] The up-conversion unit can generate a frequency hopping carrier signal according to the frequency hopping enable and frequency hopping parameters in the control instructions or generate a conventional carrier signal according to the waveform parameters, and modulate the baseband analog signal into a radio frequency signal through a quadrature modulation module

[0009] The antenna unit amplifies the power of the radio frequency signal and radiates it outward to simulate the emission process of real radar or communication signals.

[0010] As a further technical solution of the application: the DSP module is responsible for analyzing the host computer control instructions and generating waveform control words and control enables, and has channel coding, spread spectrum coding and signal feature analysis capabilities;

[0011] The FPGA module serves as a baseband signal generation module and has typical radar and communication signal modulation functions as well as DDWS capabilities, and is responsible for generating baseband modulation signals according to the control words and control enables;

[0012] The DA module is responsible for converting the baseband digital signal into an analog signal and has a low-pass filtering function to process the image frequency.

[0013] As a further technical solution of the application: the baseband signal generation module includes a data or control read-write sub-module, a memory read-write sub-module, a data processing sub-module, a large-capacity memory, a modulation sub-module and a data transmission sub-module;

[0014] The data or control read-write sub-module communicates with the DSP module according to the protocol, receives waveform data and control instructions;

[0015] The memory read-write sub-module completes the data exchange of the FPGA and the large-capacity memory according to the decoded read-write control instructions, realizes the address generation of the address generator in the DDWS and the storage and reading of the waveform data of the waveform lookup table;

[0016] The data processing sub-module decodes the received control instructions to control the operation of each sub-module, and buffers, converts the sampling rate and converts the bit width of the waveform data;

[0017] The large-capacity memory adopts DDR4 SDRAM and is used to store the waveform data of complex signals, and realizes the reading and synthesis of the waveform data through the DDWS technology to support the integration of complex radar communication signals;

[0018] The modulation submodule has typical radar or communication signal modulation capability, and can modulate waveform and symbol data into various typical radar or communication baseband signals.

[0019] The data sending submodule is responsible for processing waveform data according to control instructions and sending the processed waveform data to the DA module.

[0020] A radar communication integrated radiation source simulation method, the radiation source simulation method comprising:

[0021] S1, a user sets a simulated signal type and parameters in the host computer control unit;

[0022] S2, the host computer control unit sends a control instruction to the signal processing unit according to the signal type and parameters set by the user;

[0023] S3, the DSP module of the signal processing unit parses the control instruction sent by the host computer control unit into corresponding waveform control words and control enables;

[0024] S4, the DSP module determines whether the original symbol needs to be encoded according to the set signal type, and if so, performs source, channel and spread spectrum encoding required by the non-fixed part of the signal;

[0025] S5, the DSP module sends the waveform control word and the control enable to the baseband signal generation module;

[0026] S6, the baseband signal generation module determines whether it is a typical radar or communication signal according to the received waveform control word and control enable:

[0027] If it is a typical radar or communication signal, the data processing submodule thereof generates the required original modulation signal according to the parsed control instruction, the modulation submodule thereof selects the corresponding modulation method according to the received control word to modulate the original signal, and sends the modulated signal to the data sending submodule thereof;

[0028] If it is not a typical radar or communication signal, i.e. a complex signal, the data processing submodule thereof reads the fixed part of the corresponding complex signal waveform data from the waveform lookup table of its large-capacity storage and performs sampling rate conversion according to the parsed control instruction, and sends it to the data sending submodule, and then sends the encoded symbol data and other parameters in the parsed control instruction to the modulation submodule for corresponding digital modulation, and obtains the non-fixed part of the complex signal after data rate conversion and sends it to the data sending submodule;

[0029] S7, for a typical radar or communication signal, the data sending sub-module sends the baseband digital signal to the DA module, and for a complex signal, the data sending sub-module combines the fixed part and the non-fixed part according to the signal message format timing, and then sends the combined signal to the DA module;

[0030] S8, the DA module converts the baseband digital signal into an analog signal, filters out the image frequency component through a low-pass filter, and then sends the baseband analog signal to the up-conversion unit;

[0031] S9, the up-conversion unit determines whether the type of the analog signal is a frequency hopping signal according to the frequency hopping enable in the control instruction:

[0032] If it is a frequency hopping signal, a frequency hopping carrier signal is generated according to the frequency hopping parameters in the control instruction;

[0033] If it is not a frequency hopping signal, a conventional carrier signal is generated according to the waveform parameters in the control instruction;

[0034] S10, the quadrature modulation module of the up-conversion unit performs quadrature modulation on the carrier signal and the baseband analog signal to obtain a radio frequency signal and send the radio frequency signal to the antenna unit;

[0035] S11, the antenna unit amplifies and transmits the received radio frequency signal.

[0036] As a further technical solution of the application: in S6, the baseband signal generation module uses a signal feature analysis method based on phase difference to analyze the signal to determine whether it is a complex signal, and updates the waveform lookup table according to the determination result to expand the types of radar or communication signals that can be simulated.

[0037] As a further technical solution of the application: the complex signal includes a data link communication signal, and the waveform of the complex signal is composed of a fixed part and a non-fixed part;

[0038] The fixed part is read from a large-capacity memory and synthesized through DDWS technology, and the non-fixed part is generated in real time through a modulation module; and the two parts are combined according to the signal message format timing to generate a complete complex signal waveform.

[0039] As a further technical solution of the application: the radar or communication signal includes a linear frequency modulation signal and a phase shift keying signal, and the waveform of the radar or communication signal is generated by the modulation sub-module according to the control instruction and the modulation parameters, without accessing a large-capacity memory, and the modulation and synthesis of the signal are completed through the internal logic resources of the FPGA.

[0040] As a further technical solution of the present application: the signal feature analysis method based on phase difference receives signal time domain sampling data and calculates first order phase difference and second order phase difference by calculating phase; the range of the two phase differences is used to preliminarily judge the frequency variation characteristic: the first order phase difference is linearly fitted and the fitting error is calculated to judge whether the frequency varies linearly with time; the second order phase difference is subjected to mutation detection and clustering analysis to judge the phase jump characteristic; finally, the signal is judged as a regular signal or a complex signal according to the threshold value.

[0041] As a further technical solution of the present application: the signal feature analysis method based on phase difference specifically includes the following steps:

[0042] 1) receiving signal time domain sampling data s(n), n = 1, 2, …, N+1, calculating phase and de-wrapping to obtain phase According to Calculate the first order phase difference According to Calculate the second order phase difference

[0043] 2) Calculate the difference between the maximum and minimum of the absolute value of the two phase differences

[0044] 3) Δ is used to preliminarily judge whether the signal frequency varies linearly with time, if Δ is less than the set threshold value, go to 4), otherwise go to 6);

[0045] 4) Linear fitting is performed on the first order phase difference, and the least square method is used to obtain the fitting slope k1 and intercept b1:

[0046]

[0047] After obtaining the fitting slope k1 and intercept b1, the fitting error e1 is calculated:

[0048]

[0049] 5) e1 is used to finally judge whether the signal frequency varies linearly with time, if e1 is less than the set threshold value, the signal is judged as a regular signal, otherwise it is judged as a complex signal;

[0050] 6) Mutation detection is performed on the second order phase difference The number of points greater than the set mutation value threshold is counted, and adjacent points are merged to obtain the number of mutation points N m ;

[0051] 7) k-means clustering is performed on the second order phase difference mutation points, and the final number of clusters N is countedcluster Sort the cluster center values ​​from smallest to largest to obtain Δφ′ cluster (n), n = 1, 2, ..., N cluster ;

[0052] 8)N m Used to determine whether the signal phase has undergone a large number of abrupt changes, if N m If the signal exceeds the set threshold, it is classified as a complex signal; otherwise, proceed to step 9.

[0053] 9) For Δφ′ cluster (n) Perform linear fitting using the least squares method, and obtain the linear fitting error e2 in the same step 4).

[0054] 10) e2 is mainly used to determine whether the signal phase changes regularly. If e2 is greater than the set threshold, the signal is determined to be a normal signal; otherwise, it is determined to be a complex signal.

[0055] The beneficial effects of this invention are:

[0056] 1) By adopting a system architecture consisting of a host computer control unit, a signal processing unit, an up-conversion unit, and an antenna unit, the integrated simulation of radar and communication signals is realized, which significantly improves the realism and flexibility of electronic countermeasures training.

[0057] 2) This method innovatively introduces a phase difference-based signal feature analysis method to analyze unknown radar or communication signals. It can intelligently identify the type of unknown signals, distinguish between conventional and complex signals, and select the optimal waveform generation strategy accordingly. For unknown complex signals, DDWS technology is used to store and generate the waveform. For conventional signals, the modulation module of the signal processing unit directly generates the waveform. For known complex signals, such as data link communication signals, DDWS technology is used to pre-store the fixed part of the waveform. The non-fixed part is generated in real time by combining the FPGA modulation module. The waveform is then combined and output according to the timing of the signal message format, thereby realizing the simulation of complex signals. This meets the current electronic countermeasures training requirements for the integrated radar and communication radiation source simulation. Furthermore, it significantly reduces the occupation of FPGA logic resources and the storage requirements of waveform data, thereby effectively reducing the number of external hardware modules and promoting the miniaturization and lightweight design of the system.

[0058] 3) This method supports the simulation of frequency-hopping signals, has strong frequency domain flexibility, and can adapt to the simulation needs of complex and ever-changing electromagnetic environments. In addition, this method also has good scalability, and can continuously expand the types of signals that can be simulated by updating the waveform lookup table, so as to meet the simulation requirements of future new radar and communication signals. It has strong engineering applicability and military application value. Attached Figure Description

[0059] Figure 1 The system block diagram of the present application is shown in the figure;

[0060] Figure 2 The structure block diagram of the baseband signal generation module of the present application is shown in the figure;

[0061] Figure 3 The flow chart of the signal feature analysis method based on phase difference of the present application is shown in the figure;

[0062] Figure 4 The flow chart of the radar communication integrated radiation source signal simulation of the present application is shown in the figure. DETAILED DESCRIPTION

[0063] The technical solutions in the embodiments of the present application will be clearly and completely described below with the accompanying drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, but not all the embodiments. Based on the embodiments in the present application, all the other embodiments obtained by those skilled in the art without creative labor fall within the protection scope of the present application.

[0064] Embodiment one, as shown in the figure, provides a radar communication integrated radiation source simulation system, which comprises a host computer control unit, a signal processing unit, an up-conversion unit and an antenna unit. Figure 1

[0065] (I) The host computer control unit is responsible for sending control instructions to the signal processing unit and receiving its response information.

[0066] (II) The signal processing unit adopts the architecture of DSP module+FPGA module+DA module.

[0067] (1) The DSP module is responsible for analyzing the host computer control instructions and generating waveform control words and control enables, and has the channel coding, spread spectrum coding and signal feature analysis capabilities;

[0068] (2) The FPGA module serves as a baseband signal generation module, has the typical radar, communication signal modulation functions and DDWS capabilities, and is responsible for generating baseband modulation signals according to the control words and control enables.

[0069] As shown in the figure, the baseband signal generation module comprises a data or control read-write submodule, a memory read-write submodule, a data processing submodule, a large-capacity memory, a modulation submodule and a data sending submodule. Figure 2 The data or control read-write submodule realizes the communication between the DSP module according to the protocol, receives the waveform data and control instructions;

[0070]

[0071] ​​The memory read-write submodule completes data exchange between the FPGA and the mass storage according to the decoded read-write control instruction, and realizes address generation of the address generator in the DDWS and waveform data storage and reading of the waveform lookup table.

[0072] The data processing submodule decodes the received control instruction to control the work of each submodule in the FPGA, and buffers, converts the sampling rate and converts the bit width of the waveform data, so as to meet the sampling rate and bit width requirements of the mass storage (DDR4 SDRAM) and the data sending submodule, thereby meeting the needs of integrated simulation of complex radar communication signals.

[0073] The mass storage is DDR4 SDRAM, which is used to store waveform data of complex signals and realize reading and synthesis of the waveform data through the DDWS technology, so as to support integrated simulation of complex radar communication signals.

[0074] The modulation submodule has typical radar or communication signal modulation capability, and can modulate waveform and symbol data into various typical radar or communication baseband signals.

[0075] The data sending submodule is responsible for processing the waveform data sent by the data processing module and the waveform data completed by the modulation submodule (such as combining the fixed part and the non-fixed part of the data link communication signal according to the message format timing), and sending the processed waveform data to the DA module.

[0076] The DA module is responsible for converting the baseband digital signal into an analog signal, and has a low-pass filtering function to process the image frequency.

[0077] (Three), the up-conversion unit has frequency hopping signal generation capability, which can generate a frequency hopping carrier signal according to the frequency hopping enable and frequency hopping parameters in the control instruction, or generate a conventional carrier signal according to the waveform parameters, and modulate the baseband analog signal into a radio frequency signal through the quadrature modulation module.

[0078] (Four), the antenna unit is responsible for power amplification of the radio frequency signal and radiation to the outside, so as to simulate the emission process of real radar or communication signals.

[0079] Embodiment two provides a radar communication integrated radiation source simulation method, which is based on the radiation source simulation system of embodiment one, as shown in Figure 4 The radiation source simulation method specifically includes:

[0080] First, the user sets the simulated signal type and parameters in the host computer control unit.

[0081] Second, the host computer control unit sends corresponding control instructions to the signal processing unit according to the signal type and parameters set by the user.

[0082] Third: the DSP module of the signal processing unit parses the control instruction sent by the host computer control unit into corresponding control word and control enable, and if the symbol needs to be encoded (such as data link communication signal), the original data symbol to be encoded is included;

[0083] Fourth: the DSP module determines whether the original symbol needs to be encoded according to the set signal type, and if so, the source, channel and spread spectrum coding required by the non-fixed part of the signal are performed;

[0084] Fifth: the DSP module sends the waveform control word and control enable to the baseband signal generation module;

[0085] Sixth: the baseband signal generation module determines whether it is a typical radar or communication signal (such as LFM, PSK signal) according to the received waveform control word and control enable:

[0086] If it is a typical radar or communication signal, its data processing submodule generates the required original modulation signal according to the parsed control instruction, and its modulation submodule selects the corresponding modulation method to modulate the original signal according to the received waveform control word, and sends the modulated signal to its data sending submodule;

[0087] If it is not a typical radar or communication signal, i.e. a complex signal (such as link11 data link signal), its data processing submodule reads the fixed part (such as synchronization frame) of the corresponding complex signal waveform data from the waveform lookup table of its large capacity storage according to the parsed control instruction and sends it to the data sending submodule after sampling rate conversion, and then sends the encoded symbol data and other parameters in the parsed control instruction to the modulation submodule for corresponding digital modulation, and obtains the non-fixed part (such as data frame) of the complex signal after data rate conversion and sends it to the data sending submodule;

[0088] Seventh: for typical radar or communication signals, the data sending submodule directly sends the baseband digital signal to the DA module, and for complex signals, the data sending submodule combines the fixed part and the non-fixed part according to the signal message format timing and then sends it to the DA module;

[0089] Eighth: the DA module converts the baseband digital signal into an analog signal, and filters out the image frequency component through a low-pass filter, and then sends the baseband analog signal to the up-conversion unit;

[0090] Ninth: the up-conversion unit determines whether the type of the signal to be simulated is a frequency hopping signal according to the frequency hopping enable in the control instruction:

[0091] If it is a frequency hopping signal, a frequency hopping carrier signal is generated according to the frequency hopping parameters in the control instruction;

[0092] If it is not a frequency hopping signal, a conventional carrier signal is generated according to the waveform parameters in the control command;

[0093] Tenth: The quadrature modulation module of the upconversion unit performs quadrature modulation on the carrier signal and the baseband analog signal to obtain the radio frequency signal and send it to the antenna unit;

[0094] Eleventh: The antenna unit amplifies the received radio frequency signals and transmits them outwards.

[0095] In step "six", the baseband signal generation module uses a signal feature analysis method based on phase difference to analyze the signal to determine whether it is a complex signal, and updates the waveform lookup table according to the judgment result to expand the radar or communication signal patterns that can be simulated.

[0096] Complex signals include data link communication signals, whose waveforms consist of fixed and non-fixed parts;

[0097] The fixed part is read from a large-capacity memory and synthesized using DDWS technology, while the non-fixed part is generated in real time by a modulation module. The two parts are then combined according to the signal message format and timing to generate a complete complex signal waveform.

[0098] Radar or communication signals include linear frequency modulation signals and phase shift keying signals. Their waveforms are generated by the modulation submodule according to control commands and modulation parameters. There is no need to access large-capacity memory, and the modulation and synthesis of signals are completed through the internal logic resources of the FPGA.

[0099] like Figure 3 As shown, the phase difference-based signal feature analysis method used in the DSP module can analyze unknown signal waveform data and determine whether it is a complex signal. For unknown signals determined to be complex, they are stored as new radar / communication signal patterns in the large-capacity memory of the baseband signal generation module for future simulations. For unknown signals determined to be conventional, their frequency or phase changes regularly, indicating a known radar / communication signal pattern that can be synthesized by the modulation submodule of the baseband signal generation module. This method is used in the preparatory stage of the integrated radar and communication radiation source simulation method. Without knowing the waveform synthesis mechanism of the signal to be added to the waveform lookup table, it updates the waveform lookup table, expanding the range of radar / communication signal patterns that can be simulated. This method primarily treats signals with nonlinear frequency-time changes and irregular phase jumps as complex signals.

[0100] The signal feature analysis method based on phase difference receives time domain sampling data of a signal, calculates first order phase difference and second order phase difference by calculating phase, and preliminarily judges frequency variation characteristics by range of the two phase differences; linear fitting is performed on the first order phase difference, and fitting error is calculated to judge whether the frequency varies linearly; mutation detection and clustering analysis are performed on the second order phase difference to judge phase jump characteristics; finally, the signal is judged as a regular signal or a complex signal according to a threshold value.

[0101] The signal feature analysis method based on phase difference specifically comprises the following steps:

[0102] S1, receiving time domain sampling data s(n) of a signal to be analyzed, n=1, 2, …, N+1, calculating phase and de-rolling of the same to obtain phase According to calculating first order phase difference According to calculating second order phase difference

[0103] S2, calculating difference between maximum value and minimum value of absolute values of the two phase differences

[0104] S3, Δ is used for preliminarily judging whether the signal frequency varies linearly with time, if Δ is less than a set threshold value, then S4 is entered, otherwise S6 is entered;

[0105] S4, linear fitting is performed on the first order difference, least square method is adopted to obtain fitting slope k1 and intercept b1:

[0106]

[0107] After obtaining the fitting slope k1 and the intercept b1, fitting error e1 is calculated:

[0108]

[0109] S5, e1 is used for finally judging whether the signal frequency varies linearly with time, if e1 is less than a set threshold value, then the signal is judged as a regular signal (such as a single frequency signal and a linear frequency modulation signal), otherwise it is judged as a complex signal;

[0110] S6, mutation detection is performed on the second order phase difference , the number of points greater than a set mutation value threshold is counted, and adjacent points are merged to obtain the number N of mutation points m ;

[0111] S7, k-means clustering is performed on the second order phase difference mutation points, and the finally obtained cluster number N is countedcluster The cluster center values ​​are sorted from smallest to largest to obtain Δφ′. cluster (n), n = 1, 2, ..., N cluster ;

[0112] S8, N m It is mainly used to determine whether the signal phase has undergone a large number of abrupt changes. If N m If the signal exceeds the set threshold, it is classified as a complex signal; otherwise, proceed to step S9.

[0113] S9, regarding Δφ′ cluster (n) Perform linear fitting using the least squares method, and obtain the linear fitting error e2 in the same step S4.

[0114] S10 and e2 are mainly used to determine whether the phase of the signal changes regularly (such as PSK signal). If e2 is greater than the set threshold, the signal is determined to be a normal signal; otherwise, it is determined to be a complex signal.

[0115] Working Principle: For known complex signals (such as data link communication signals), a fixed portion of the signal message format is pre-stored using high-capacity Double Data Rate Synchronous Dynamic Random Access Memory (DDR SDRAM). Then, DDWS technology is used to generate this waveform. The non-fixed waveform portion is generated using the modulation module in the FPGA. Finally, the two are combined according to the signal message format timing to simulate the known complex signal. This saves FPGA logic resources and the amount of waveform data that needs to be stored, thereby reducing the number of external hardware circuit modules required for the simulation system and contributing to system miniaturization and weight reduction. For unknown signals, a phase difference-based signal feature analysis method is used to analyze them. Based on the analysis results, an appropriate waveform generation method is selected to improve the system's scalability.

[0116] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the invention can be implemented in other specific forms without departing from its spirit or essential characteristics. Therefore, the embodiments should be considered in all respects as exemplary and non-limiting, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, all variations falling within the meaning and scope of equivalents of the claims are intended to be included within the present invention. No reference numerals in the claims should be construed as limiting the scope of the claims.

[0117] Furthermore, it should be understood that although the specification is described in terms of embodiments, not every embodiment includes every feature or implementation described herein. The specification can include implicit combinations of explicitly mentioned features and / or implicit combinations of implicitly mentioned features. Such combinations are also expressly included within the scope of the specification and an embodiment.

Claims

1. A radar-communication integrated radiated source simulation system, characterized in that, The radiation source simulation system comprises: A host computer control unit responsible for sending control instructions to the signal processing unit and receiving its response information; The signal processing unit adopts a DSP module+FPGA module+DA module architecture; The up-conversion unit can generate a frequency hopping carrier signal according to the frequency hopping enable and frequency hopping parameters in the control instruction or a conventional carrier signal according to the waveform parameters, and modulate the baseband analog signal into a radio frequency signal through a quadrature modulation module The antenna unit amplifies the radio frequency signal and radiates it outward to simulate the transmission process of real radar or communication signals.

2. The radiation source simulation system of claim 1, wherein: The DSP module is responsible for analyzing the host computer control instructions and generating waveform control words and control enables, and has channel coding, spread spectrum coding and signal feature analysis capabilities; The FPGA module serves as a baseband signal generation module and has typical radar and communication signal modulation functions and DDWS capabilities, and is responsible for generating baseband modulation signals according to the control words and control enables; The DA module is responsible for converting the baseband digital signal into an analog signal and has a low-pass filtering function to process the image frequency.

3. The radiation source modeling system of claim 2, wherein: The baseband signal generation module includes a data or control read-write sub-module, a memory read-write sub-module, a data processing sub-module, a large-capacity memory, a modulation sub-module, and a data sending sub-module; The data or control read-write sub-module communicates with the DSP module according to the protocol, receives waveform data and control instructions; The memory read-write sub-module completes the data exchange between the FPGA and the large-capacity memory according to the decoded read-write control instructions, realizes the address generation of the address generator in the DDWS, and stores and reads the waveform data of the waveform lookup table; The data processing sub-module decodes the received control instructions to control the operation of each sub-module, and buffers, samples, and converts the bit width of the waveform data; The large-capacity memory adopts DDR4 SDRAM to store the waveform data of complex signals, and realizes the reading and synthesis of waveform data through DDWS technology to support the integrated simulation of complex radar communication signals; The modulation sub-module has typical radar or communication signal modulation capabilities and can modulate waveform and symbol data into various typical radar or communication baseband signals; The data sending sub-module is responsible for processing the waveform data according to the control instructions and sending the processed waveform data to the DA module.

4. A radar-communication integrated emitter simulation method, comprising the emitter simulation system of claim 3, characterized in that, The radiation source simulation method comprises: S1, the user sets the signal type and parameters to be simulated in the host computer control unit; S2, the host computer control unit sends control instructions to the signal processing unit according to the signal type and parameters set by the user; S3, the DSP module of the signal processing unit parses the control instructions sent by the host computer control unit into corresponding waveform control words and control enables; S4, the DSP module determines whether the original symbol needs to be encoded according to the set signal type, and if so, performs source, channel and spread spectrum coding of the non-fixed part of the signal; S5, the DSP module sends the waveform control words and control enables to the baseband signal generation module; S6, the baseband signal generation module determines whether it is a typical radar or communication signal according to the received waveform control word and control enable: If it is a typical radar or communication signal, its data processing submodule generates the required original modulation signal according to the parsed control instruction, its modulation submodule selects the corresponding modulation method to modulate the original signal according to the received control word, and sends the modulated signal to its data sending submodule; If it is not a typical radar or communication signal, i.e. a complex signal, its data processing submodule reads the fixed part of the corresponding complex signal waveform data from the waveform lookup table of its mass storage and performs sampling rate conversion after reading, and then sends it to the data sending submodule, and then sends the encoded symbol data and other parameters in the parsed control instruction to the modulation submodule for corresponding digital modulation, and then performs data rate conversion to obtain the non-fixed part of the complex signal and sends it to the data sending submodule; S7, for typical radar or communication signals, the data sending submodule sends the baseband digital signal to the DA module, and for complex signals, the data sending submodule combines the fixed part and the non-fixed part according to the signal message format timing and then sends it to the DA module; S8, the DA module converts the baseband digital signal into an analog signal, filters out the image frequency component through a low-pass filter, and then sends the baseband analog signal to the up-conversion unit; S9, the up-conversion unit determines whether the type of the analog signal is a frequency hopping signal according to the frequency hopping enable in the control instruction: If it is a frequency hopping signal, generate a frequency hopping carrier signal according to the frequency hopping parameters in the control instruction; If it is not a frequency hopping signal, generate a regular carrier signal according to the waveform parameters in the control instruction; S10, the quadrature modulation module of the up-conversion unit performs quadrature modulation on the carrier signal and the baseband analog signal to obtain the radio frequency signal and send it to the antenna unit; S11, the antenna unit amplifies the received radio frequency signal and transmits it outward.

5. The radiation source simulation method of claim 4, wherein: In S6, the baseband signal generation module uses a signal feature analysis method based on phase difference to analyze the signal to determine whether it is a complex signal, and updates the waveform lookup table according to the determination result to expand the types of radar or communication signals that can be simulated.

6. The radiation source simulation method of claim 5, wherein: The complex signal includes a data link communication signal, and its waveform is composed of a fixed part and a non-fixed part; Wherein, the fixed part is read from the mass storage and synthesized through the DDWS technology, and the non-fixed part is generated in real time through the modulation module; and the two parts are combined according to the signal message format timing to generate the complete complex signal waveform.

7. The radiation source simulation method of claim 5, wherein: The radar or communication signal includes a linear frequency modulation signal and a phase shift keying signal, and its waveform is generated by the modulation submodule according to the control instruction and modulation parameters, without accessing the mass storage, and the modulation and synthesis of the signal are completed through the internal logic resources of the FPGA.

8. The radiation source simulation method of claim 6, wherein: The phase difference-based signal feature analysis method calculates first-order phase difference and second-order phase difference by receiving signal time domain sampling data and calculating phase; preliminarily judges frequency variation characteristics through range of two phase differences; judges whether the frequency varies linearly by linear fitting the first-order phase difference and calculating fitting error; judges phase jump characteristics by mutation detection and clustering analysis of the second-order phase difference; and finally judges the signal as a regular signal or a complex signal according to a threshold value.

9. The radiation source simulation method of claim 8, wherein, The phase difference-based signal feature analysis method specifically comprises the following steps: 1) receive the time domain sample data s(n) of the signal to be analyzed, n = 1, 2, …, N+1, take the phase and unwrap it to get the phase According to Calculate the first-order phase difference According to Calculate the second-order phase difference 2) Calculate the difference between the maximum and minimum of the two phase difference absolute values 3) Δ is used to preliminarily judge whether the signal frequency varies linearly with time, if Δ is less than a preset threshold value, step 4) is entered, otherwise step 6) is entered; 4) linear fitting is performed on the first-order phase difference, and a least square method is used to obtain a fitting slope k1 and an intercept b1: After the fitting slope k1 and the intercept b1 are obtained, a fitting error e1 is calculated: 5) e1 is used to finally judge whether the signal frequency varies linearly with time, if e1 is less than a preset threshold value, the signal is judged as a regular signal, otherwise it is judged as a complex signal; 6) on second order phase difference Mutation detection is performed, the number of points greater than the set mutation value threshold is counted, and adjacent points are merged to obtain the number N of mutation points m ; 7) k-means clustering for second order phase difference differential mutation point, counting the final cluster number N cluster Sort the cluster center value from small to large to get Δφ' cluster (n), n = 1, 2, …, N cluster ; 8) N m If the phase of the signal is determined to have a large number of mutations, if N m is greater than a predetermined threshold, the signal is determined to be a complex signal, otherwise, step 9) is entered. 9) Δφ' = φ' - φ cluster (n) Linear fitting is performed on Δφ' using the least square method, and the linear fitting error e2 is obtained according to step 4); 10) e2 is used to judge whether the signal phase regularly jumps, if e2 is greater than a preset threshold value, the signal is judged as a regular signal, otherwise it is judged as a complex signal.

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