A multi-functional integrated signal waveform design method

Abstract

The application discloses a multifunctional integrated signal waveform design method, which comprises the following steps: obtaining task target information and current electromagnetic environment information of three types of tasks of radar, communication and active jamming respectively, establishing a waveform design criterion of multifunctional integration, and determining performance indexes of the multifunctional integrated waveform; establishing a waveform design objective function according to the performance indexes of the multifunctional integrated waveform, the task target information and the electromagnetic environment information, solving the waveform design objective function, and obtaining a multifunctional integrated signal waveform; evaluating effects of executing the tasks of radar, communication and active jamming, and re-designing the multifunctional integrated signal waveform according to the evaluation result. The application comprehensively considers the task target information and the electromagnetic environment information of radar, communication and active jamming, utilizes a waveform to realize bearing of the three types of functions, and realizes the waveform design of multifunctional integration in a specific scene.

Description

Technical Field

[0001] This invention relates to the fields of communications, radar, and active jamming, and in particular to a multifunctional integrated signal waveform design method. Background Technology

[0002] Currently, with the continuous development of broadband radio frequency devices and ultra-wideband signal processing technology, radar systems, communication systems, and active jamming systems are showing a trend of hardware integration. For radar systems, the detection bandwidth is becoming increasingly wider, and some radars even possess passive detection and signal identification and sorting capabilities. Therefore, future radars are expected to achieve more active jamming functions. For active jamming systems, they are constantly advancing with radar technology, and the technologies used in signal waveform generation, signal transmission, and beamforming are becoming increasingly similar to those of radar systems. Deep integration of the two systems and the use of a single hardware to implement both functions is a future technological trend. Furthermore, the radio frequency front-end architectures of radar and wireless communication technologies are becoming increasingly similar, and there are already general-purpose hardware platforms capable of implementing both radar and communication functions. Therefore, radar, communication, and active jamming systems are expected to be designed using a unified hardware architecture, achieving hardware platform integration. However, for systems that integrate radar, communication, and jamming, how to design waveforms that can simultaneously support radar, communication, and active jamming functions is a pressing issue that needs to be addressed. Summary of the Invention

[0003] To address the problem of designing an integrated waveform capable of simultaneously carrying radar, communication, and active jamming functions, this invention discloses a multi-functional integrated signal waveform design method, comprising:

[0004] The system acquires mission target information and current electromagnetic environment information for three types of tasks: radar, communication, and active jamming.

[0005] Based on the acquired mission objective information and electromagnetic environment information, a multi-functional integrated waveform design standard is established;

[0006] Based on the established waveform design criteria, the performance indicators of the multi-functional integrated waveform are determined.

[0007] Based on the performance indicators, mission objective information, and electromagnetic environment information of the multi-functional integrated waveform, a waveform design objective function is established.

[0008] Based on the established waveform design objective function, the corresponding solution method is used to solve the waveform design objective function to obtain a multi-functional integrated signal waveform;

[0009] The effectiveness of a multi-functional integrated system using a multi-functional integrated signal waveform in performing radar, communication, and active jamming tasks is evaluated, and evaluation results are obtained. When the evaluation results exceed the preset range, the task target information and electromagnetic environment information for the three tasks of radar, communication, and active jamming are modified according to the evaluation results. Based on the modified task target information and electromagnetic environment information, the multi-functional integrated signal waveform is redesigned.

[0010] The radar's mission target information includes radar mission type, target type, target electromagnetic characteristics information, target motion characteristics information, etc.

[0011] The target types include subsonic targets, supersonic targets, and hypersonic targets;

[0012] The communication task objective information includes communication channel information, communication reliability requirements information, and communication effectiveness requirements information, etc.

[0013] The active jamming target information includes the jamming target's technical system, the jamming target platform's motion characteristics, the jamming target's operating status, the jamming target's signal parameter information, and the active jamming mode.

[0014] The current electromagnetic environment information is obtained by characterizing the current electromagnetic environment using a hierarchical cognitive model.

[0015] The aforementioned hierarchical cognitive model for representing the current electromagnetic environment involves using a basic attribute layer, a physical space layer, a waveform morphology layer, a signal waveform layer, a fingerprint feature layer, a basic data layer, and an information application layer to represent the current electromagnetic environment data, thereby obtaining the representation parameter information for each layer. The representation parameter information of all layers constitutes the current electromagnetic environment information.

[0016] The basic attribute layer is characterized by parameter information including signal bandwidth, average power spectral density, and maximum power spectral density.

[0017] The physical space layer is characterized by parameters including spatial spectral density, spatial beam density, and minimum spatial spectral spacing.

[0018] The waveform morphology layer is characterized by parameters including horizontal and vertical polarization ratio and joint polarization space spectrum information.

[0019] The signal waveform layer, whose characterization parameter information includes signal waveform parameter information, etc.

[0020] The fingerprint feature layer includes modulation parameter information, etc.

[0021] The basic data layer's representation parameter information includes symbol parameter information, etc.

[0022] The information application layer's characterization parameter information includes interference pattern information, etc.

[0023] The waveform design principles for the multi-functional integrated system include: waveform design principles for radar functions, waveform design principles for communication functions, and waveform design principles for active jamming functions.

[0024] The establishment of a multi-functional integrated waveform design criterion based on the acquired mission objective information and electromagnetic environment information includes:

[0025] The detection environment signal-to-noise ratio is evaluated based on the radar's mission target information and electromagnetic environment information to obtain the detection environment signal-to-noise ratio evaluation value; if the detection environment signal-to-noise ratio evaluation value is lower than the preset value, the target echo signal-to-noise ratio criterion is adopted as the waveform design criterion for radar function.

[0026] The target electromagnetic characteristics information in the radar's mission target information is obtained. If the target electromagnetic characteristics are extended target characteristics where electromagnetic scattering intensity changes with frequency, then the target estimation accuracy criterion is used as the waveform design criterion for radar functions.

[0027] The electromagnetic characteristics of the target are obtained from the radar's mission target information. If the electromagnetic characteristics of the target are random target characteristics that change randomly, the target classification criteria are used as the waveform design criteria for the radar function.

[0028] If the radar mission type in the radar's mission target information is target detection and search, then the target echo signal-to-noise ratio criterion is used as the waveform design criterion for radar functions.

[0029] If the radar mission type in the radar's mission target information is target tracking, then the target estimation accuracy criterion is used as the waveform design criterion for radar functions.

[0030] If the radar mission type in the radar's mission target information is target identification, then the target classification criterion is used as the waveform design criterion for the radar function.

[0031] If the communication channel information in the communication task objective information provides a lower limit for the channel capacity, then the channel capacity criterion shall be used as the waveform design criterion for the communication function.

[0032] Based on the communication mission objective information, if the communication channel information does not constrain the channel capacity, and the communication reliability requirement is higher than the communication effectiveness requirement, then the communication reliability criterion is used as the waveform design criterion for the communication function; if the communication channel information does not constrain the channel capacity, and the communication effectiveness requirement is higher than the communication reliability requirement, then the communication effectiveness criterion is used as the waveform design criterion for the communication function.

[0033] If the active interference mode of the target information of the active interference is suppression interference, then the suppression interference effectiveness criterion shall be used as the waveform design criterion for the active interference function.

[0034] If the active interference mode of the target information of the active interference is deception interference, then the deception interference effectiveness criterion shall be used as the waveform design criterion for the active interference function.

[0035] The step of determining the performance indicators of the multi-functional integrated waveform according to the established waveform design criteria includes: selecting the corresponding waveform performance indicators according to the waveform design criteria.

[0036] The performance indicators of the waveform corresponding to the target estimation accuracy criterion include range CRB, velocity CRB, and target scattering coefficient CRB.

[0037] The waveform performance indicators corresponding to the target echo signal-to-noise ratio criterion include the ambiguity function and the coherent accumulation characteristic;

[0038] The performance indicators of the waveform corresponding to the target classification criteria include the conditional mutual information between the radar received signal and the random target;

[0039] The performance indicators of the waveform corresponding to the channel capacity criterion include channel capacity.

[0040] The performance indicators of the waveform corresponding to the communication effectiveness criteria include data transmission rate;

[0041] The performance indicators of the waveform corresponding to the communication reliability criteria include the communication bit error rate;

[0042] The performance indicators of the waveform corresponding to the interference suppression effectiveness criterion include the interference waveform entropy value;

[0043] The performance indicators of the waveform corresponding to the deception interference effectiveness criterion include the similarity between the interference waveform and the interference target waveform.

[0044] The step of establishing a waveform design objective function based on the performance indicators, mission objective information, and electromagnetic environment information of the multi-functional integrated waveform includes:

[0045] Based on the determined waveform performance indicators for each task, a waveform design objective function containing multiple indicators is established. Based on the acquired task objective information and electromagnetic environment information, the constraints of the waveform design objective function are determined. The expression of the waveform design objective function containing multiple indicators is as follows:

[0046]

[0047] Where x is the parameter vector of the multi-functional integrated waveform, x = [x1, x2, x3], x1, x2, and x3 are the parameter vectors affecting the performance indicators of radar mission, communication mission, and active jamming mission, respectively. f1(x1), f2(x2), and f3(x3) are the performance indicator functions of radar mission, communication mission, and active jamming mission, respectively. w1, w2, and w3 are the weights corresponding to the above three performance indicator functions. p1(x1), p2(x2), and p3(x3) are the constraint inequalities of radar mission, communication mission, and active jamming mission, respectively.

[0048] The step of solving the waveform design objective function using a corresponding solution method includes:

[0049] If the objective function of waveform design is a convex optimization problem, then the optimization method should be used to solve it;

[0050] If the waveform design objective function is not a convex optimization problem, machine learning methods are used to solve it. In machine learning methods, a loss function or gain function is constructed using the waveform design objective function.

[0051] When using machine learning methods to solve the problem, the statistical quantity of the acquired electromagnetic environment information is evaluated. If this statistical quantity exhibits time-varying characteristics, then reinforcement learning methods are used to solve the waveform design objective function. Reinforcement learning is a type of machine learning method.

[0052] The optimization methods include the Lagrange multiplier method, the Pareto method, and genetic algorithms.

[0053] The beneficial effects of this invention are as follows:

[0054] (I) This application comprehensively considers the target mission information of radar, communication and active jamming and the electromagnetic environment information. It extracts the requirements of three different missions from the above information and then constructs the waveform design objective function. This ensures that the designed waveform function can simultaneously meet the requirements of radar, communication and active jamming. It uses a single waveform to carry the above three functions and realizes the multi-functional integrated waveform design in a specific scenario.

[0055] (ii) After completing the multi-functional integrated waveform design, this application evaluates the waveform's performance and modifies the waveform design requirements based on changes in the electromagnetic environment, thereby enabling the designed waveform to be updated and iterated according to changes in functional requirements. Attached Figure Description

[0056] Figure 1 This is a flowchart illustrating the implementation of the method of the present invention. Detailed Implementation

[0057] To better understand the content of this invention, two embodiments are given here.

[0058] Figure 1 This is a flowchart illustrating the implementation of the method of the present invention.

[0059] Example 1:

[0060] This embodiment discloses a multifunctional integrated signal waveform design method, including:

[0061] The system acquires mission target information and current electromagnetic environment information for three types of tasks: radar, communication, and active jamming.

[0062] Based on the acquired mission objective information and electromagnetic environment information, a multi-functional integrated waveform design standard is established;

[0063] Based on the established waveform design criteria, the performance indicators of the multi-functional integrated waveform are determined.

[0064] Based on the performance indicators, mission objective information, and electromagnetic environment information of the multi-functional integrated waveform, a waveform design objective function is established.

[0065] Based on the established waveform design objective function, the corresponding solution method is used to solve the waveform design objective function to obtain a multi-functional integrated signal waveform;

[0066] The effectiveness of a multi-functional integrated system using multi-functional integrated signal waveforms in performing radar, communication, and active jamming tasks is evaluated, and evaluation results are obtained. When the evaluation results exceed the preset range, the task target information and electromagnetic environment information for the three types of tasks (radar, communication, and active jamming) are modified based on the evaluation results.

[0067] If the mission target information and electromagnetic environment information for radar, communication, and active jamming are modified, then the multi-functional integrated signal waveform design must be carried out again based on the modified mission target information and electromagnetic environment information.

[0068] The radar's mission target information includes radar mission type, target type, target electromagnetic characteristics information, target motion characteristics information, etc.

[0069] The target types include subsonic targets, supersonic targets, and hypersonic targets;

[0070] The communication task objective information includes communication channel information, communication reliability requirements information, and communication effectiveness requirements information, etc.

[0071] The active jamming target information includes the jamming target's technical system, platform motion characteristics, operational status, signal parameters, and active jamming mode. This active jamming target information can be obtained through the active jamming reconnaissance channel of a multi-functional integrated system.

[0072] The current electromagnetic environment information is obtained by characterizing the current electromagnetic environment using a hierarchical cognitive model.

[0073] The aforementioned hierarchical cognitive model for representing the current electromagnetic environment involves using a basic attribute layer, a physical space layer, a waveform morphology layer, a signal waveform layer, a fingerprint feature layer, a basic data layer, and an information application layer to represent the current electromagnetic environment data, thereby obtaining the representation parameter information for each layer. The representation parameter information of all layers constitutes the current electromagnetic environment information.

[0074] The basic attribute layer is characterized by parameter information including signal bandwidth, average power spectral density, and maximum power spectral density.

[0075] The physical space layer is characterized by parameters including spatial spectral density, spatial beam density, and minimum spatial spectral spacing.

[0076] The waveform morphology layer is characterized by parameters including horizontal and vertical polarization ratio and joint polarization space spectrum information.

[0077] The signal waveform layer, whose characterization parameter information includes signal waveform parameter information, etc.

[0078] The fingerprint feature layer includes modulation parameter information, etc.

[0079] The basic data layer's representation parameter information includes symbol parameter information, etc.

[0080] The information application layer's characterization parameter information includes interference pattern information, etc.

[0081] The waveform design principles for the multi-functional integrated system include: waveform design principles for radar functions, waveform design principles for communication functions, and waveform design principles for active jamming functions.

[0082] The establishment of a multi-functional integrated waveform design criterion based on the acquired mission objective information and electromagnetic environment information includes:

[0083] The detection environment signal-to-noise ratio is evaluated based on the radar's mission target information and electromagnetic environment information to obtain the detection environment signal-to-noise ratio evaluation value; if the detection environment signal-to-noise ratio evaluation value is lower than the preset value, the target echo signal-to-noise ratio criterion is adopted as the waveform design criterion for radar function.

[0084] The step of evaluating the signal-to-noise ratio (SNR) of the detection environment based on the radar's mission target information and electromagnetic environment information to obtain an evaluation value for the detection environment SNR includes:

[0085] The target electromagnetic scattering intensity value is obtained by using the target electromagnetic characteristic information in the radar mission target information. The environmental power value is obtained by using the average power spectral density of the basic attribute layer in the current electromagnetic environment information. The result of dividing the target electromagnetic scattering intensity value by the environmental power value is used as the signal-to-noise ratio evaluation value of the detection environment.

[0086] The target electromagnetic characteristics information in the radar's mission target information is obtained. If the target electromagnetic characteristics are extended target characteristics where electromagnetic scattering intensity changes with frequency, then the target estimation accuracy criterion is used as the waveform design criterion for radar functions.

[0087] The electromagnetic characteristics of the target are obtained from the radar's mission target information. If the electromagnetic characteristics of the target are random target characteristics that change randomly, the target classification criteria are used as the waveform design criteria for the radar function.

[0088] If the radar mission type in the radar's mission target information is target detection and search, then the target echo signal-to-noise ratio criterion is used as the waveform design criterion for radar functions.

[0089] If the radar mission type in the radar's mission target information is target tracking, then the target estimation accuracy criterion is used as the waveform design criterion for radar functions.

[0090] If the radar mission type in the radar's mission target information is target identification, then the target classification criterion is used as the waveform design criterion for the radar function.

[0091] Based on the characterization parameters of the information application layer of the current electromagnetic environment information, the waveform design criteria for radar and communication functions are determined. If the characterization parameters of the information application layer of the current electromagnetic environment information indicate that the radar is suppressing interference, the communication reliability criterion is used as the waveform design criterion for the communication function, and the target echo signal-to-noise ratio criterion is used as the waveform design criterion for the radar function.

[0092] If the communication channel information in the communication task objective information provides a lower limit for the channel capacity, then the channel capacity criterion shall be used as the waveform design criterion for the communication function.

[0093] Based on the communication mission objective information, if the communication channel information does not constrain the channel capacity, and the communication reliability requirement is higher than the communication effectiveness requirement, then the communication reliability criterion is used as the waveform design criterion for the communication function; if the communication channel information does not constrain the channel capacity, and the communication effectiveness requirement is higher than the communication reliability requirement, then the communication effectiveness criterion is used as the waveform design criterion for the communication function.

[0094] If the active interference mode of the target information of the active interference is suppression interference, then the suppression interference effectiveness criterion shall be used as the waveform design criterion for the active interference function.

[0095] If the active interference mode of the target information of the active interference is deception interference, then the deception interference effectiveness criterion shall be used as the waveform design criterion for the active interference function.

[0096] In practical applications, priorities can be set for the various types of information contained in the task objective information. The waveform design criteria for the task are determined first using the information with the highest priority. If the waveform design criteria for the task cannot be determined using the information with the highest priority, then the waveform design criteria for the task are determined using the information with the next lower priority, until the waveform design criteria for the task are determined.

[0097] The step of determining the performance indicators of the multi-functional integrated waveform according to the established waveform design criteria includes: selecting the corresponding waveform performance indicators according to the waveform design criteria.

[0098] The performance indices of the waveform corresponding to the target estimation accuracy criterion include range CRB, velocity CRB, and target scattering coefficient CRB. CRB refers to the lower bound of the unbiased estimation variance.

[0099] The waveform performance indicators corresponding to the target echo signal-to-noise ratio criterion include the ambiguity function and the coherent accumulation characteristic;

[0100] The performance indicators of the waveform corresponding to the target classification criteria include the conditional mutual information between the radar received signal and the random target;

[0101] The performance indicators of the waveform corresponding to the channel capacity criterion include channel capacity.

[0102] The performance indicators of the waveform corresponding to the communication effectiveness criteria include data transmission rate;

[0103] The performance indicators of the waveform corresponding to the communication reliability criteria include the communication bit error rate;

[0104] The performance indicators of the waveform corresponding to the interference suppression effectiveness criterion include the interference waveform entropy value;

[0105] The performance indicators of the waveform corresponding to the deception interference effectiveness criterion include the similarity between the interference waveform and the interference target waveform.

[0106] The step of establishing a waveform design objective function based on the performance indicators, mission objective information, and electromagnetic environment information of the multi-functional integrated waveform includes:

[0107] Based on the determined waveform performance indicators for each task, a waveform design objective function containing multiple indicators is established. Based on the acquired task objective information and electromagnetic environment information, the constraints of the waveform design objective function are determined. The expression of the waveform design objective function containing multiple indicators is as follows:

[0108]

[0109] Where x is the parameter vector of the multi-functional integrated waveform, x = [x1, x2, x3], x1, x2, and x3 are the parameter vectors affecting the performance indicators of radar mission, communication mission, and active jamming mission, respectively. f1(x1), f2(x2), and f3(x3) are the performance indicator functions of radar mission, communication mission, and active jamming mission, respectively. w1, w2, and w3 are the weights corresponding to the above three performance indicator functions. p1(x1), p2(x2), and p3(x3) are the constraint inequalities of radar mission, communication mission, and active jamming mission, respectively.

[0110] The step of solving the waveform design objective function using a corresponding solution method includes:

[0111] If the objective function of waveform design is a convex optimization problem, the optimization method should be used to solve it;

[0112] If the waveform design objective function is not a convex optimization problem, machine learning methods can be used to solve it. In machine learning methods, the waveform design objective function is used to construct a loss function or a gain function.

[0113] When using machine learning methods to solve the problem, the statistical quantity of the acquired electromagnetic environment information is judged. If the statistical quantity exhibits time-varying characteristics, then reinforcement learning methods are used to solve the waveform design objective function.

[0114] The optimization methods include the Lagrange multiplier method, the Pareto method, and genetic algorithms.

[0115] This embodiment uses OFDM signals as the basic signal for multi-functional integrated signal design. By modifying its parameters or adding new modulation dimensions independent of OFDM amplitude and phase modulation, multi-functional integrated signal design is achieved. Assuming x(t) represents the OFDM baseband signal transmitted by the multi-functional integrated system, and y(t) represents the corresponding far-field received baseband signal, then the expression for x(t) is:

[0116]

[0117] The OFDM signal has a time length of N. symT+T cp The modulated pulse is transmitted, N sym b represents the time length of an OFDM symbol. η The weighting coefficients are obtained by solving the waveform design objective function during the pulse design process. All weighting coefficients constitute a weighting coefficient vector b, where b = [b1, b2, ..., b...]. N The weighted coefficient vector b is also part of the parameter vector of the multi-functional integrated waveform, T cp Indicates the duration of the loop prefix. Let T represent a rectangular window function with period T, μ represent the index of the OFDM symbol within a modulation pulse, η represent the index of the OFDM subcarrier within a modulation pulse, and a (μ,η) f represents the amplitude of the ηth subcarrier of the μth symbol. η Let represent the ηth OFDM subcarrier, t represent time, and N represent the number of OFDM subcarriers. Let d Tx (μ,η) represents the modulation information at the transmitting end, the distance between the target and the multi-functional integrated signal transmitter is R, and the Doppler frequency shift caused by the relative velocity between the target and the multi-functional integrated signal transmitter is f. D Then the expression for y(t) is:

[0118]

[0119] Where c0 represents the speed of light. The received modulation information d Rx (μN+η) is represented in matrix form to obtain the receiving matrix. Prime division is performed on the receiving matrix to obtain the target matrix, which contains target range and Doppler frequency offset information and is independent of modulation information. Windowing operations are performed on the row and column vectors of the matrix to obtain the windowed matrix. DFT operation is performed on each row of the windowed matrix to obtain the DFT result. The target velocity corresponding to the row with the maximum value of the DFT result is the estimated value of the target relative velocity. IDFT operation is performed on each column of the windowed matrix to obtain the IDFT result. The target range corresponding to the column with the maximum value of the IDFT result is the estimated value of the target range.

[0120] The establishment of a multi-functional integrated waveform design criterion based on the acquired mission objective information and electromagnetic environment information includes:

[0121] The target electromagnetic characteristics in the radar mission target information are extended target characteristics where electromagnetic scattering intensity changes with frequency. The target estimation accuracy criterion is used as the waveform design criterion for radar functions. Based on the communication rate constraints and bit error rate constraints given in the communication mission target information, the corresponding lower limit of channel capacity is calculated, and the channel capacity criterion is used as the waveform design criterion for communication functions. The active jamming mode in the active jamming mission target information is suppression jamming, and the suppression jamming effectiveness criterion is used as the waveform design criterion for active jamming functions.

[0122] The process involves establishing a waveform design objective function based on the performance indicators, mission objective information, and electromagnetic environment information of the multi-functional integrated waveform; then, based on the determined waveform design objective function, solving the waveform design objective function using appropriate solution methods to obtain the multi-functional integrated signal waveform, including:

[0123] For an OFDM multi-functional integrated signal x(t), its total channel capacity under frequency-selective fading and Gaussian white noise channel is:

[0124]

[0125] Where Δf is the bandwidth of the OFDM subchannel, b η The weighted coefficients are the weighting coefficients, and all the weighted coefficients form a weighted coefficient vector b, b = [b1, b2, ..., b...]. N ], h η For the frequency response of the ηth OFDM subchannel, Let p be the channel noise power. For OFDM signals, the ηth subcarrier corresponds to the ηth subchannel. Based on the communication mission objective information, determine the constraint condition p on the weighting coefficient vector b. b,c With the goal of maximizing the total channel capacity of the OFDM multi-functional integrated signal x(t), a waveform design sub-function for the communication task is established, the expression of which is:

[0126]

[0127] Solve the waveform design sub-function for the communication task to obtain the optimal value C of the total channel capacity. t_max ;

[0128] Using the OFDM multi-function integrated signal x(t) as the radar signal, the CRB value for target range estimation is calculated. R (b) and the CRB value of the target velocity estimate. v (b) Based on the radar's mission target information, determine the constraint condition p on the weighting coefficient vector b. b,r For target distance estimation, a corresponding waveform design sub-function is established, the expression of which is:

[0129]

[0130] Solving the waveform design subfunction yields the optimal CRB value CR for target distance estimation; for target velocity estimation, a corresponding waveform design subfunction is established, with the following expression:

[0131]

[0132] Solve the waveform design sub-function to obtain the optimal CRB value CV for target velocity estimation;

[0133] Using the OFDM multi-function integrated signal x(t) as the suppression interference signal, the entropy value of its interference waveform is calculated using the following formula:

[0134]

[0135] Where a is the entropy constant; based on the task objective information of the active interference, the constraint condition p on the weighting coefficient vector b is determined. b,j For the entropy value of the interference waveform, a corresponding waveform design sub-function is established, the expression of which is:

[0136]

[0137] Solving the waveform design sub-function yields the optimal entropy value H of the interference waveform. o Taking into account radar, communication, and active jamming requirements, a multi-functional integrated waveform design objective function is established, the expression of which is:

[0138]

[0139] An optimization method is used to solve the objective function of the multi-functional integrated waveform design, and the optimal weight vector b is obtained. o ; the optimal weight vector b o Substituting the waveform expression x(t), the final multifunctional integrated waveform is obtained. The optimization solution method used to solve the objective function of the multifunctional integrated waveform design can be the Pareto method, machine learning method, etc.

[0140] Example 2:

[0141] This embodiment uses the multi-functional integrated signal waveform design method disclosed in Embodiment 1 for waveform design. The step of establishing multi-functional integrated waveform design criteria based on the acquired task objective information and electromagnetic environment information includes:

[0142] The target electromagnetic characteristics in the radar's mission target information are extended target characteristics where electromagnetic scattering intensity varies with frequency. The target estimation accuracy criterion is used as the waveform design criterion for radar functions. Based on the communication rate constraints and bit error rate constraints given in the communication mission target information, the corresponding channel capacity lower limit is calculated, and the channel capacity criterion is used as the waveform design criterion for communication functions. The active jamming mode in the mission target information is deception jamming. The deception jamming effectiveness criterion is used as the waveform design criterion for active jamming functions. The performance index of the waveform corresponding to the deception jamming effectiveness criterion is the similarity between the jamming waveform and the jamming target waveform. The waveform similarity is obtained by calculating the Euclidean distance between the received waveform and the jamming waveform. For deception jamming, the waveform received by the receiving channel is r(t). After passing through the radio frequency storage and transponder, the waveform is deceptively modulated to generate a deception waveform. The pulse portion je(t) of the deception waveform is extracted. The weighting coefficient vector in je(t) is denoted as jv. jv determines the waveform shape of the pulse portion je(t). The formula for calculating the waveform similarity L(jv) is:

[0143] L(jv)=∫[je(t)-r(t)) 2 dt,

[0144] Based on the deception and interference mission objective information, determine the constraint condition p on the weighted coefficient vector jv. b,j1 For waveform similarity, a corresponding waveform design sub-function is established, the expression of which is:

[0145]

[0146] Solve the waveform design sub-function to obtain the optimal waveform similarity L of the interference waveform. o In this scenario, radar and communication functions are implemented using OFDM waveforms, whose expression remains x(t), and whose weighting coefficient vector is also b. The jamming waveform and the OFDM waveform are within the same pulse period, but there is a time interval T0 between them in the time domain. The value of the time interval T0 is determined by the effectiveness of radar target detection and deception jamming, based on the criteria of maximizing radar detection probability and achieving optimal deception jamming effect. In this scenario, the expression for the multi-functional integrated waveform is:

[0147] x1(t) = x(t) + je(t + T0);

[0148] Taking into account the requirements of radar, communication, and active jamming, the objective function for waveform design of this multi-functional integrated system is established, and its expression is:

[0149]

[0150] An optimization method is used to solve the objective function of the multi-functional integrated waveform design, and the optimal weight vector b is obtained. o and jv0; the optimal weight vector b o Substitute the waveform expression x(t) into the waveform expression je(t+T0), and then substitute the optimal weight vector jv0 into the waveform expression je(t+T0) to obtain the corresponding x1(t). Use x1(t) as the final multi-functional integrated waveform.

[0151] The above description is merely an embodiment of this application and is not intended to limit the scope of this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the scope of the claims of this application.

Claims

1. A multifunctional integrated signal waveform design method, characterized in that, The method includes: The system acquires mission target information and current electromagnetic environment information for three types of tasks: radar, communication, and active jamming. Based on the acquired mission objective information and electromagnetic environment information, a multi-functional integrated waveform design standard is established, including: The detection environment signal-to-noise ratio is evaluated based on the radar's mission target information and electromagnetic environment information to obtain the detection environment signal-to-noise ratio evaluation value; if the detection environment signal-to-noise ratio evaluation value is lower than the preset value, the target echo signal-to-noise ratio criterion is adopted as the waveform design criterion for radar function. The target electromagnetic characteristics information in the radar's mission target information is obtained. If the target electromagnetic characteristics are extended target characteristics where electromagnetic scattering intensity changes with frequency, then the target estimation accuracy criterion is used as the waveform design criterion for radar functions. The electromagnetic characteristics of the target are obtained from the radar's mission target information. If the electromagnetic characteristics of the target are random target characteristics that change randomly, the target classification criteria are used as the waveform design criteria for the radar function. If the radar mission type in the radar's mission target information is target detection and search, then the target echo signal-to-noise ratio criterion is used as the waveform design criterion for radar functions. If the radar mission type in the radar's mission target information is target tracking, then the target estimation accuracy criterion is used as the waveform design criterion for radar functions. If the radar mission type in the radar's mission target information is target identification, then the target classification criterion is used as the waveform design criterion for the radar function. If the communication channel information in the communication task objective information provides a lower limit for the channel capacity, then the channel capacity criterion shall be used as the waveform design criterion for the communication function. Based on the communication mission objective information, if the communication channel information does not constrain the channel capacity, and the communication reliability requirement is higher than the communication effectiveness requirement, then the communication reliability criterion is used as the waveform design criterion for the communication function; if the communication channel information does not constrain the channel capacity, and the communication effectiveness requirement is higher than the communication reliability requirement, then the communication effectiveness criterion is used as the waveform design criterion for the communication function. If the active interference mode of the target information of the active interference is suppression interference, then the suppression interference effectiveness criterion shall be used as the waveform design criterion for the active interference function. If the active interference mode of the target information of the active interference is deception interference, then the deception interference effectiveness criterion shall be used as the waveform design criterion for the active interference function. Based on the established waveform design criteria, the performance indicators of the multi-functional integrated waveform are determined. Based on the performance indicators, mission objective information, and electromagnetic environment information of the multi-functional integrated waveform, a waveform design objective function is established. Based on the established waveform design objective function, the corresponding solution method is used to solve the waveform design objective function to obtain a multi-functional integrated signal waveform; The effectiveness of a multi-functional integrated system using multi-functional integrated signal waveforms in performing radar, communication, and active jamming tasks was evaluated, and the evaluation results were obtained. When the evaluation result exceeds the preset range, the mission target information and electromagnetic environment information of the three types of tasks (radar, communication, and active jamming) are modified according to the evaluation result. Based on the modified mission target information and electromagnetic environment information, the multi-functional integrated signal waveform is redesigned.

2. The multifunctional integrated signal waveform design method as described in claim 1, characterized in that, The radar's mission target information includes radar mission type, target type, target electromagnetic characteristics information, and target motion characteristics information; The communication task objective information includes communication channel information, communication reliability requirement information, and communication effectiveness requirement information; The active jamming target information includes the jamming target's technical system, the jamming target's platform motion characteristics, the jamming target's operating status, the jamming target's signal parameter information, and the active jamming mode.

3. The multifunctional integrated signal waveform design method as described in claim 1, characterized in that, The current electromagnetic environment information is obtained by characterizing the current electromagnetic environment using a hierarchical cognitive model.

4. The multifunctional integrated signal waveform design method as described in claim 3, characterized in that, The aforementioned hierarchical cognitive model for characterizing the current electromagnetic environment involves using a basic attribute layer, a physical space layer, a waveform morphology layer, a signal waveform layer, a fingerprint feature layer, a basic data layer, and an information application layer to characterize the current electromagnetic environment data, thereby obtaining the characterization parameter information for each layer. The characterization parameter information of all layers constitutes the current electromagnetic environment information. The basic attribute layer is characterized by parameter information including signal bandwidth, average power spectral density, and maximum power spectral density. The physical space layer is characterized by parameters including spatial spectral density, spatial beam density, and minimum spatial spectral spacing. The waveform morphology layer is characterized by parameters including the horizontal-vertical polarization ratio and the joint polarization space spectrum. The signal waveform layer, whose characterization parameter information includes signal waveform parameter information; The fingerprint feature layer includes modulation parameter information in its characterization parameter information. The basic data layer includes symbol parameter information in its representation parameter information. The information application layer's characterization parameter information includes interference pattern information.

5. The multifunctional integrated signal waveform design method as described in claim 1, characterized in that, The waveform design principles for the multi-functional integrated system include: waveform design principles for radar functions, waveform design principles for communication functions, and waveform design principles for active jamming functions.

6. The multifunctional integrated signal waveform design method as described in claim 1, characterized in that, The step of determining the performance indicators of the multi-functional integrated waveform according to the established waveform design criteria includes: selecting the corresponding waveform performance indicators according to the waveform design criteria. The performance indicators of the waveform corresponding to the target estimation accuracy criterion include range CRB, velocity CRB, and target scattering coefficient CRB; The performance indicators of the waveform corresponding to the target echo signal-to-noise ratio criterion include ambiguity function and coherent accumulation characteristics; The performance indicators of the waveform corresponding to the target classification criteria include the conditional mutual information between the radar received signal and the random target. The performance indicators of the waveform corresponding to the channel capacity criterion include channel capacity; The performance indicators of the waveform corresponding to the communication effectiveness criteria include data transmission rate; The performance indicators of the waveform corresponding to the communication reliability criteria include the communication bit error rate; The performance index of the waveform corresponding to the interference suppression effectiveness criterion includes the interference waveform entropy value. The performance indicators of the waveform corresponding to the deception interference effectiveness criterion include the similarity between the interference waveform and the interference target waveform.

7. The multifunctional integrated signal waveform design method as described in claim 1, characterized in that, The step of establishing a waveform design objective function based on the performance indicators, mission objective information, and electromagnetic environment information of the multi-functional integrated waveform includes: Based on the determined waveform performance indicators for each task, a waveform design objective function containing multiple indicators is established. Based on the acquired task objective information and electromagnetic environment information, the constraints of the waveform design objective function are determined. The expression of the waveform design objective function containing multiple indicators is as follows: ， ， in, The parameter vector of the multi-functional integrated waveform. , , and These are parameter vectors that affect radar mission performance indicators, communication mission performance indicators, and active jamming mission performance indicators, respectively. , and These are the performance index functions for radar missions, communication missions, and active jamming missions, respectively. , and These are the weights corresponding to the three performance index functions mentioned above. , and These are the constraint inequalities for radar missions, communication missions, and active jamming missions, respectively.

8. The multifunctional integrated signal waveform design method as described in claim 1, characterized in that, The step of solving the waveform design objective function using a corresponding solution method includes: If the objective function of waveform design is a convex optimization problem, then the optimization method should be used to solve it; If the objective function for waveform design is not a convex optimization problem, machine learning methods can be used to solve it.

9. The multifunctional integrated signal waveform design method as described in claim 8, characterized in that, The method employs machine learning to solve the problem, and determines the statistical quantity of the acquired electromagnetic environment information. If the statistical quantity exhibits time-varying characteristics, then reinforcement learning is used to solve the waveform design objective function.

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