Multi-system signal generation method and device

Abstract

The invention provides a multi-system signal generation method and device, and the method comprises the steps: obtaining a signal system type and a signal parameter of a target signal according to a signal generation instruction; generating a control instruction sequence and a modulation parameter according to the system type and the signal parameter, and generating a configuration parameter of a target according to the signal modulation parameter; modulating an original signal according to the control instruction and the configuration parameters to obtain a modulated signal, the modulation model being an intermediate baseband signal; filtering and shaping the modulation signal to obtain a target signal; and acquiring a first analog signal input from the outside, converting the target signal into a second analog signal, and collecting, playing back and storing the first analog signal and the second analog signal as sample signals. The method has the beneficial effects that the generation of the multi-system signal is realized, and the compatibility and switching efficiency of the generation of the multi-system signal are improved.

Description

Technical Field

[0001] The present invention relates to the field of signal processing technology, and in particular to a multi-system signal generation method and device. Background Art

[0002] With the advancement of technology and the rapid development of the times, the demand for diverse, high-performance, and highly adaptable signal systems across various industries has skyrocketed. In the communications sector, the challenges and diverse demands faced by electronic warfare, a critical application fraught with both competition and challenges, have become increasingly prominent. In today's complex electromagnetic environment, the use of communication frequency bands faces numerous challenges. On the one hand, various communication methods are subject to various interference factors, raising concerns about signal transmission stability. On the other hand, different communication platforms and mission scenarios place complex and diverse demands on comprehensive communications.

[0003] Radar systems also face challenges, including increasingly complex target characteristics. For example, stealth targets utilize specialized design and absorbing coatings to reduce their radar cross-section, making them difficult to detect. Furthermore, small, low-flying, slow-moving targets, with their low altitude, slow speed, and small reflection cross-section, are difficult for conventional radar to detect. Furthermore, the ever-changing detection environment includes electromagnetic interference, including natural lightning electromagnetic pulse interference, as well as man-made electronic interference and high-intensity electromagnetic interference.

[0004] The field of electronic countermeasures is like a fierce electromagnetic competition training ground, requiring equipment to be able to quickly generate interference or reconnaissance signal systems that can accurately counter the opponent's dynamically changing signals. Among them, interference signals include targeted interference, which is a high-intensity interference against a specific frequency signal; blocking interference, which transmits strong interference signals in a wider frequency band, covering multiple communication or radar frequencies; and smart interference, which analyzes the real-time frames of the received signal parameters and quickly generates targeted interference signals, thereby controlling electromagnetic power.

[0005] Most existing signal generation technologies have problems such as single function, poor compatibility, and delayed signal system switching. Summary of the Invention

[0006] The main purpose of the embodiments of the present invention is to provide a multi-system signal generation method and device, which realizes the generation of multi-system signals and improves the compatibility and switching efficiency of the multi-system signal generation.

[0007] One aspect of the present invention provides a multi-system signal generation method, characterized by comprising:

[0008] According to the signal generation instruction, the signal system type and signal parameters of the target signal are obtained;

[0009] generating a control instruction sequence and modulation parameters according to the system type and the signal parameters, and generating target configuration parameters according to the signal modulation parameters;

[0010] Modulating the original signal according to the control instruction and configuration parameters to obtain a modulated signal, wherein the modulation model is an intermediate baseband signal;

[0011] Performing filtering and shaping processing on the modulated signal to obtain a target signal;

[0012] A first analog signal input from the outside is obtained, and the target signal is converted into a second analog signal. The first analog signal and the second analog signal are collected, played back, and stored as sample signals.

[0013] According to the multi-system signal generation method, obtaining the signal system type and signal parameters of the target signal according to the signal generation instruction includes:

[0014] According to the signal generation instruction, an analytical algorithm is used to obtain the signal system type and signal parameters of the target signal, where the signal system type includes communication signals, radar signals and interference signals; the signal parameters include frequency range, bandwidth, modulation mode and coding type.

[0015] According to the multi-system signal generation method, generating a control instruction sequence and modulation parameters according to the system type and the signal parameters includes:

[0016] generating a control instruction sequence using an analytical algorithm according to the signal system type, querying an instruction library to obtain the control instruction sequence, and generating the modulation parameters according to the control instruction sequence;

[0017] The control instruction sequence generated by the analytical algorithm is stored, and the analytical algorithm is optimized using the stored control instruction sequence.

[0018] According to the multi-system signal generation method, the original signal is modulated according to the control instruction and configuration parameters to obtain a modulated signal, including:

[0019] According to the signal system type, the corresponding modulation algorithm is used to perform modulation processing. When the signal system type is a communication signal, modulation mapping and shaping filtering processing are performed; when the signal system type is a radar signal, time domain modulation and frequency domain modulation processing are performed; when the signal system type is an interference signal, the interference strategy is dynamically modulated according to the characteristics of the interference signal.

[0020] According to the multi-system signal generation method, filtering and shaping the modulated signal to obtain the target signal includes:

[0021] performing a spurious frequency removal process on the intermediate baseband signal according to the signal parameters, and then performing waveform optimization, wherein the waveform optimization includes aligning the spectral purity and waveform regularity of the intermediate baseband signal with those of the target signal to obtain an intermediate frequency signal;

[0022] The intermediate frequency signal is converted to obtain the target signal.

[0023] According to the multi-system signal generation method, obtaining a first analog signal input from an external source, converting the target signal into a second analog signal, and collecting, replaying, and storing the first analog signal and the second analog signal as sample signals include:

[0024] After the target signal is converted by DAC and sampled, a second analog signal is obtained, and the time-frequency spectrum and time-frequency parameters of the second analog signal are played back;

[0025] The coupled signal input from the outside is sampled to obtain the first analog signal, the first analog signal and the second analog signal are subjected to signal detection and signal parameter estimation, and sample data is generated and stored.

[0026] Another aspect of an embodiment of the present invention provides a multi-system signal generating device, including:

[0027] A signal control module is configured to obtain the signal system type and signal parameters of the target signal according to the signal generation instruction; to generate a control instruction sequence and modulation parameters according to the system type and the signal parameters, and to generate target configuration parameters according to the signal modulation parameters;

[0028] A signal modulation generation module is used to modulate the original signal according to the control instruction and configuration parameters to obtain a modulated signal, wherein the modulation model is an intermediate baseband signal;

[0029] A signal shaping conversion module, configured to filter and shape the modulated signal to obtain a target signal;

[0030] The signal shaping and conversion module is further used to obtain a first analog signal input from an external source, and convert the target signal into a second analog signal;

[0031] The signal shaping and conversion module is used to perform signal detection processing and signal parameter estimation on the first analog signal and the second analog signal in sequence to obtain sample data;

[0032] The signal control module is used to play back the sample data;

[0033] The data storage module is used to store sample data, baseband data and signal library.

[0034] According to the multi-system signal generating device, the signal control module adopts Feiteng D2000 CPU.

[0035] According to the multi-system signal generating device, the signal modulation generating module adopts the Fudan Micro JFM9VU13P chip.

[0036] According to the multi-system signal generating device, the signal shaping and conversion module adopts the Fudan Micro JFM9RFVU3P5G chip.

[0037] The beneficial effects of the present invention are: realizing the generation of multi-system signals and improving the compatibility and switching efficiency of the multi-system signal generation. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] The above and / or additional aspects and advantages of the present invention will become apparent and readily understood from the following description of the embodiments with reference to the accompanying drawings, in which:

[0039] Figure 1 It is a flowchart of a multi-system signal generation method according to an embodiment of the present invention.

[0040] Figure 2 Schematic diagram of a device for generating signals of various systems according to an embodiment of the present invention.

[0041] Figure 3 This is a flow chart of communication signal generation according to an embodiment of the present invention.

[0042] Figure 4 4 is a flow chart of radar signal generation according to an embodiment of the present invention.

[0043] Figure 5 This is a flow chart of interference signal generation according to an embodiment of the present invention.

[0044] Figure 6 This is a complete multi-system signal generation flow chart of an embodiment of the present invention.

[0045] Figure 7 It is a schematic diagram of the orthogonal modulation generation principle of the communication signal generator according to an embodiment of the present invention.

[0046] Figure 8 This is a flowchart of implementing serial signal noise addition in an embodiment of the present invention.

[0047] Figure 9 4 is a block diagram of a sampling rate conversion design according to an embodiment of the present invention.

[0048] Figure 10 This is a block diagram of a digital direct synthesis radar signal design according to an embodiment of the present invention.

[0049] Figure 11 This is a block diagram of interference signal generation according to an embodiment of the present invention.

[0050] Figure 12 This is a block diagram of an interference signal generation based on DDS according to an embodiment of the present invention.

[0051] Figure 13 This is a block diagram of interference signal generation based on DRFM according to an embodiment of the present invention. DETAILED DESCRIPTION

[0052] The following describes embodiments of the present invention in detail. Examples of the embodiments are shown in the accompanying drawings, where the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. In the subsequent description, suffixes such as "module," "component," or "unit" used to represent elements are used solely to facilitate the description of the present invention and have no specific meaning in themselves. Therefore, "module," "component," or "unit" may be used interchangeably. "First," "second," and the like are used solely to distinguish technical features and should not be construed as indicating or implying relative importance or implicitly indicating the number of the indicated technical features or implicitly indicating the order of the indicated technical features. In this subsequent description, the consecutive numbering of method steps is for ease of review and understanding. In conjunction with the overall technical solution of the present invention and the logical relationship between the various steps, adjusting the order of implementation of the steps does not affect the technical effects achieved by the technical solution of the present invention. The embodiments described below with reference to the accompanying drawings are exemplary and are intended only to explain the present invention and should not be construed as limiting the present invention.

[0053] Figure 1 A flow chart of a multi-system signal generation method, including but not limited to steps S100 to S500:

[0054] S100, acquiring a signal system type and signal parameters of a target signal according to a signal generation instruction;

[0055] S200, generating a control instruction sequence and modulation parameters according to the system type and signal parameters, and generating target configuration parameters according to the signal modulation parameters;

[0056] S300, modulating the original signal according to the control instruction and the configuration parameters to obtain a modulated signal, wherein the modulation model is an intermediate baseband signal;

[0057] S400, filtering and shaping the modulated signal to obtain a target signal;

[0058] S500 , obtaining a first analog signal input from an external source, converting a target signal into a second analog signal, and collecting, replaying, and storing the first analog signal and the second analog signal as sample signals.

[0059] refer to Figure 2 ,in Figure 2This is a schematic diagram of a multi-system signal generation device, which includes:

[0060] Based on the signal requirements input from the application software interface and the system's pre-set signal instruction library, the signal control module receives signal generation instructions from the D2000 CPU and calculates a signal generation instruction sequence. This signal generation instruction sequence includes key information such as signal type, frequency range, modulation method, and pulse parameters.

[0061] The signal control module can generate original source data for the communication signal according to the signal generation instruction sequence, and perform channel coding, baseband code conversion and other processing to obtain the original bit stream data after channel processing, providing rich and flexible configuration means for the source data processing of the communication signal.

[0062] The signal control module can call the existing local sample data from the data storage module and send the data to the signal modulation generation module through the high-speed bus according to the needs of sample signal playback. It can directly convert the sample data into a sampling rate and then perform analog waveform playback to meet the flexible adaptation needs of special application scenarios.

[0063] In some embodiments, the signal control module can process signal generation instructions through a built-in parsing algorithm, and the algorithm can sort historical instruction data according to instruction response time, push instructions with fast response to the front, achieve the effect of self-learning optimization, and improve the accuracy and efficiency of instruction parsing.

[0064] After receiving the command, the signal modulation generation module relies on the excellent performance and massive logic resources of the Fudan Micro JFM9VU13P chip to quickly select the corresponding internal signal modulation algorithm unit, and perform meticulous phase and amplitude signal modulation processing on the original signal generated by the internal reference source or the bit stream data generated by the receiving signal control module, and introduce noise under different signal-to-noise ratios. It simultaneously integrates the frequency hopping and spread spectrum algorithm logic to quickly convert the original signal into preliminary characteristics that meet the signal requirements or an intermediate baseband signal with hopping and spreading characteristics, and quickly transmits it to the signal shaping and conversion module.

[0065] In some embodiments, the internal signal modulation algorithm unit of the signal modulation generation module covers a variety of modulation methods in the fields of communication, radar, electronic countermeasures, etc., and supports the import and integration of user-defined modulation algorithms to expand the flexibility of signal modulation.

[0066] After receiving the intermediate baseband signal, the signal shaping conversion module uses the programmable filter of the Fudan Microelectronics JFM9RFVU3P5G chip to fine-tune the filter characteristics and further eliminate spurious frequencies, following the filtering and shaping parameters specifically set by the signal control module for that specific signal. The signal shaping circuit then deeply optimizes the waveform, ensuring that the signal meets the prototype signal standards in terms of spectral purity and waveform regularity. This generates a high-quality intermediate frequency signal, which is then converted to an analog signal via a high-performance DAC and played back on demand. The sampled signal is then collected and stored in the data storage module through loopback coupling as new sample signal data. During real-time acquisition, this also serves as a reference for adjusting signal output characteristics, optimizing signal output quality in a timely manner.

[0067] In some embodiments, the device as a whole has a signal quality self-diagnosis function. By receiving the generated analog signal amplitude, carrier frequency, bandwidth and other quality parameters in real time, it can quickly locate and prompt the fault point, thereby improving the reliability and maintenance convenience of the device.

[0068] Figure 3 This is a flow chart for communication signal generation in an embodiment of the present invention. When generating a communication signal, an instruction sequence containing parameters such as the modulation method (e.g., QAM, PSK digital modulation), symbol rate, and PCM framing method is generated based on the input remote sensing satellite signal generation requirements. The specific process involves parsing and converting user requirements, translating high-level application requirements into low-level executable signal parameter instructions. The algorithm employed includes a state machine-based instruction generation algorithm, which determines the next signal generation instruction based on the current system state and input conditions.

[0069] Similarly, if Figure 4 Radar signal generation flow chart and Figure 5 Interference signal generation flow chart. When radar signals need to be generated, such as complex radar signals with linear frequency modulation (positive slope) and phase coding (four-phase code), or deceptive interference signals in the field of electronic countermeasures, the equipment follows a similar operating process. Only in the instruction parsing of the signal control module and the algorithm and parameter adaptation of each module are targetedly adjusted according to different system requirements, the required multi-system signals can be generated efficiently and accurately, fully meeting the complex and changeable application demands in different fields.

[0070] The supported signal system types are detailed as follows:

[0071] 1) Communication signal:

[0072] The source of information data can be fixed code, random number, function value, file data, etc., which can meet the simulation of different information content in different test scenarios.

[0073] Coding method: Comprehensive support for cutting-edge coding technologies such as Turbo, LDPC, RS, concatenated code (RS + convolutional code), BCH, convolutional code, TPC, TCC, and TCM, laying a solid foundation for communication reliability and transmission efficiency.

[0074] Baseband code type: fully supports multiple code types such as NRZ-L, NRZ-M, NRZ-S, Biφ-L, Biφ-M, Biφ-S, RNRZ-L, etc., fully meeting the code type conversion processing of different application scenarios.

[0075] Signal types: Widely covers CW, AM, FM, DSB, SSB (USB, LSB), FMFM, BPSK, QPSK, UQPSK, OQPSK, FQPSK, π / 4DQPSK, 2FSK, 4FSK, 8FSK, MSK, 8PSK, 16PSK, 8QAM, 16QAM, 32QAM, 64QAM, 128QAM, 256QAM, 16APSK, 32APSK, GMSK, PCM-CDMA-BPSK, PCM-CDMA-QPSK, PCM-CDMA-OQPSK and other rich and diverse communication signal forms to meet different communication scenarios and needs.

[0076] Frequency Hopping: The system supports frequency hopping of passing signals, achieving an ultra-high hopping speed of up to 40,000 hops / s, effectively avoiding interference and improving communication confidentiality and stability. Furthermore, the system can adjust the hopping sequence in real time according to the channel environment during the frequency hopping process to optimize communication performance.

[0077] 2) Radar Signals: Deeply supports the generation of multiple and complex radar signal systems such as conventional pulses, linear frequency modulation (positive slope, negative slope, variable slope), nonlinear frequency modulation (sine wave, sawtooth wave, triangle wave), phase coding (binary code, four-phase code, multi-phase code), frequency agility, frequency diversity, repetition jitter, repetition difference, secondary radar, TACAN, etc., empowering radar detection accuracy, resolution and anti-interference capabilities. At the same time, it has the ability to automatically optimize radar signal parameters according to the target echo characteristics, thereby improving detection efficiency.

[0078] 3) Interference signal: It can strongly support the generation of multiple types of interference patterns, including noise interference, single-tone interference, multi-tone interference, swept frequency interference, comb spectrum interference, clutter interference, deceptive interference, and smart interference. It provides protection for building a solid electromagnetic defense line in the field of electronic countermeasures, and can adjust the interference strategy in real time according to the characteristics of the opponent's electromagnetic signal to enhance the interference effect.

[0079] Figure 6This is a complete multi-system signal generation flow chart. This embodiment of the present invention utilizes a vector signal generation method to control I / Q signal parameters to ultimately generate the target signal. Signal generation considers four scenarios: communication signals, radar signals, interference signals, and data playback. The device integrates functional modules that simultaneously generate multiple signal types, meeting the needs of signal simulation applications in diverse fields.

[0080] Depend on Figure 6 It can be seen that there are two main ways to generate modulated signals. One is that the host computer generates them directly, and the FPGA logic is only responsible for changing the sampling rate and frequency. The other way is that the host computer is responsible for generating the baseband bit stream data, and the FPGA logic is responsible for subsequent functions such as constellation mapping, shaping filtering, and changing the sampling rate.

[0081] Constellation mapping is processed according to different signal patterns. For example, BPSK is binary phase shift keying, where the 0° phase of the carrier represents data 0 and the 180° phase represents data 1. Suppose the input binary bit data stream is {b n}∈{0,1}, the output signal of BPSK is:

[0082]

[0083] Among them, A0 is the amplitude, ω c is the angular frequency, is the initial phase, t is the time, b n is the nth bit, which takes the value 0 or 1, T b is the bit period.

[0084] The principles of QPSK and 8PSK are similar to BPSK. QPSK uses four carrier phases to represent four two-bit combinations of transmission code elements 00, 01, 10, and 11 respectively; 8PSK uses eight carrier phases to represent eight three-bit combinations of transmission code elements 000, 001, 010, 011, 100, 101, 110, and 111 respectively.

[0085] The quadrature modulation I and Q components of the MPSK modulated signal are (M = 2, 4, 8) respectively:

[0086]

[0087] {b n}∈{0,…,M-1}

[0088] In order to meet the high symbol rate requirement, let the symbol rate be R s , the sampling rate is 8 times oversampling, that is, F s =8·R s, system clock CLK = 300MHz. When Fs ≤ CLK, symbol mapping, oversampling, and shaping filtering can be implemented using a single channel. When Fs > CLK, a parallel multi-channel implementation is required.

[0089] At a 300MHz clock, assuming a symbol rate of 10Msym and a sampling rate of 80Msps, this means that a symbol is bit-mapped once every 30 clock cycles. Because the signal requires 8x oversampling, this symbol sample must be repeated eight times within 30 clock cycles (8 clocks are needed to indicate a valid signal).

[0090] The input DAC sampling rate is 2400 Msps, and the input signal is an IQ baseband signal. When the symbol rate to clock ratio is not an integer, for example, when the symbol rate is 10.24 Msps and the sampling rate is 81.92 Msps, the clock interval between two symbols is 29.296875 clocks, which is not an integer. Therefore, rounding is performed. That is, the first symbol is bit-mapped starting at clock 0, the second symbol is bit-mapped starting at clocks round(29.296875 * 1), and the nth symbol is bit-mapped starting at clocks round(29.296875 * (n-1)). The round operation indicates rounding.

[0091] When the symbol rate to clock ratio is not an integer, the clock to sampling rate ratio should not be too small to ensure signal generation accuracy (CLK / Fs must be greater than or equal to 2). Since the DAC input sampling rate is 2400Msps, the maximum FPGA clock is 2400MHz, which means an 8-channel IQ implementation (8 channels each for IQ signals) is used. Since the maximum symbol rate is 600Msym, a power-of-2 oversampling factor is used for implementation convenience, so the maximum oversampling factor in this case can only be 2. For simplicity, only one multi-channel implementation is used, namely 8 channels, with a clock of 2400MHz. When the symbol rate to clock ratio is not an integer multiple, the maximum sampling rate after oversampling is 1200Msps. Therefore, when the symbol rate is greater than 300Msym, the oversampling factor of the shaping filter is 2.

[0092] For example, if the symbol rate is 102.4 Msym, the sampling rate after 4x oversampling is 409.6 Msps. A multichannel implementation is required, so the clock is 2400 MHz. With these parameters, the clock-to-symbol rate ratio is 46.875. This means that, based on the understanding of a single-channel signal, the signal, after repeated 4 clock mappings, is output to the next stage within 23.4375 clocks. However, in the multichannel case, since all eight channels share a signal valid indicator, two symbols must be mapped together: the first four samples of the eight channels are the first symbol, and samples 5 through 8 are the second symbol. When mapping the third and fourth symbols, the required interval is round(2*23.4375) clocks, corresponding to the data valid indicator duration clock of round(2*23.4375 / 8 = 5.8594). Similarly, when the oversampling is 2, four symbols must be mapped simultaneously, and the interval is multiplied by 4.

[0093] The oversampled data is fed into a shaping filter for shaping filtering. Shaping filtering is divided into single-channel filtering and parallel multi-channel filtering. They correspond to single-channel and eight-channel input signals, respectively. It is also divided into two IQ channels. The shaping filter module uses a low-pass filter with a square-root raised cosine roll-off characteristic to complete the shaping process of the baseband signal. Each symbol contains four sampling points, and 8 symbols are selected and truncated. The coefficients of the raised cosine filter are quantized to 16 bits and saved as a coe file. The FIR IP core in the FPGA is then called to implement the root raised cosine filter function. After the constellation-mapped data passes through the shaping filter, the data rate is quadrupled.

[0094] Figure 7 This is the principle behind quadrature modulation generation in communication signal generators. The communication signal generation module uses quadrature modulation to generate signals. Users can select a signal type, customize signal parameters, or import the desired signal based on their needs. By controlling the code source, code source mapping, and I and Q input parameters, the desired complex baseband signal is generated. This signal is then fed into a high-speed DAC for digital quadrature upconversion and D / A conversion, resulting in the desired intermediate frequency analog signal.

[0095] Figure 8 This is a flowchart for implementing serial signal noise addition. For high-speed, parallel noise addition of multiple signals, the time-domain signals are output in parallel, making time-domain accumulation and calculating signal energy computationally complex. Therefore, this design performs noise addition on each signal individually, applying the aforementioned serial signal noise addition steps to complete the noise addition process.

[0096] The steps of serial noise addition based on FPGA are as follows:

[0097] 1. The Gaussian noise with a storage length of M has a noise power spectrum density of n ob ;

[0098] 2. Calculate the energy of N discrete signals in the time domain;

[0099] 3. Calculate the scaling factor k based on the signal energy in the time domain, the signal bandwidth, and the set signal-to-noise ratio. The signal bandwidth and signal-to-noise ratio are sent by the host computer. The calculation formula for the communication signal bandwidth is as follows;

[0100] B w =(1+α)·B s

[0101] Among them B s is the symbol rate of the signal, α is the shaping factor of the shaping filter, and when there is no shaping filter, α = 1. When the signal is other signals, its signal bandwidth should be set by the user.

[0102] 4. Use the level l m sequence as the address to access the noise stored in ROM;

[0103] 5. Multiply the noise output by the ROM by the scaling factor k and add it to the signal to complete the noise addition function.

[0104] Figure 9 Design a block diagram for sampling rate conversion. The sampling rate of the signal after shaping filtering depends solely on the signal's symbol rate, but the DAC input sampling rate is fixed, so sampling rate conversion is required to meet the DAC input requirements. This requires both integer and fractional sampling rate conversions. This design accommodates both playback data sampling rate conversion and modulation generation data sampling rate conversion. Of all the signals requiring 2x interpolation, only the generated modulation signal has eight parallel inputs. Therefore, before entering the interpolation filter, the number of data channels is converted using a FIFO. The selection of the FIFO is controlled by the input signal sampling rate. After the signal is interpolated to between 1200 and 2400 Msps, an eight-channel farrow interpolation filter is applied to convert the signal sampling rate to 2400 Msps. Since the minimum oversampling factor for shaping filtering is 2x, and interpolation filtering is always performed at 2x, a half-band filter is considered for interpolation filtering.

[0105] Figure 10This is a flowchart for the workflow of radar signal generation using digital direct synthesis. Radar signal generation is achieved using digital direct synthesis technology. The waveform generation solution based on digital direct synthesis technology has the advantages of high integration, small size, stable and reliable operation, and very flexible waveform formation, which can meet the requirements of complex radar signal forms. When generating radar signals, DDS can generate any signal waveform based on the accumulator output phase. In other words, DDS technology can directly modulate one, two, or three of the generated signal waveform parameters (such as frequency, phase, and amplitude) simultaneously. Taking frequency modulation as an example, the output frequency of a DDS system is given by the following formula:

[0106]

[0107] Where: k is the frequency control word, f clock is the DDS input clock frequency, and n is the number of bits of the phase accumulator.

[0108] The radar signal generation unit implements the radar signal basic information model based on the received signal parameters, and generates a pulse data stream after calculation. The radar signal basic information model mainly includes the pulse carrier frequency f RF Arrival time t TOA , pulse width τ pW , pulse power P A , intra-pulse modulation information F, etc., the above parameters t TOA , τ pW 、P A , F constitute a pulse data stream.

[0109] Figure 11 This is a block diagram for interference signal generation. Interference signal input and output are accomplished via both ADCs and DACs. Based on the reconnaissance results from the digital reconnaissance unit, the host computer selects either a digital channelized architecture or a parallel architecture based on DRFM to simulate the interference signal. The host computer selects the appropriate interference pattern based on the digital reconnaissance unit, and the final data is output via the DAC. After digital channelization, the signal is converted to a baseband signal. This allows for easy processing of the received signal at a low data rate, generating the baseband interference signal and target analog signal. Using digital inverse channelization, the baseband interference signal and target analog signal are upconverted, filtered, and interpolated before being transmitted via the digital-to-analog converter (DAC). Because digital channelization desamples and downscales the original signal after ADC sampling, the interference simulation architecture based on the channelized architecture generates the interference and target analog signals at low data rates, effectively reducing hardware resource usage.

[0110] Figure 12This is a block diagram for DDS-based interference signal generation. For suppressive interference generation, the signal utilizes a complex baseband signal model. By controlling the timing, complex envelope, and phase value at any given moment, various complex baseband representations of the signal can be generated. Through multiple filtering, interpolation, and digital upconversion, the required digital waveform intermediate frequency signal is generated and sent to the transmitter. Since a sinusoidal modulated signal is required, a DDS can be used to generate a low-frequency sinusoidal signal as the modulating signal. The desired signal frequency is then calculated based on the interference bandwidth and the interference center frequency. This frequency is then input into the DDS's frequency control word to control the output frequency. When generating sweep signals of sawtooth and triangle waves, an accumulation function can be written to generate the sawtooth wave. The frequency of the sawtooth wave is controlled by controlling the accumulation step. The triangle wave is generated by folding the sawtooth wave back. For convenience, and considering that sawtooth and triangle sweeps are often used in conjunction with a sine sweep, the phase signal output by the DDS is used directly as the sawtooth signal source, while the triangle wave is generated using the sawtooth wave. After obtaining the modulated signal, the signal frequency to be generated each time is calculated based on the interference bandwidth and the center frequency of the interference. Finally, the frequency is input into the frequency control word of the DDS to realize the control of the output frequency.

[0111] Figure 13 This is a block diagram of interference signal generation based on DRFM. The DRFM-based interference signal generation process includes storing target signal data, reading target signal data, and processing the target signal data to generate an interference signal or simulate a target echo. Specific tasks within the FPGA include signal detection and parameter measurement, digital down-conversion and up-conversion, signal storage, timing control signal generation, signal modulation, and ADC and DAC interface control.

[0112] Throughout this specification, reference to terms such as "one embodiment," "some embodiments," "examples," "specific examples," or "some examples" means that a specific feature, structure, material, or characteristic described in conjunction with that embodiment or example is included in at least one embodiment or example of the present invention. In this specification, schematic representations of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

[0113] While embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions, and variations may be made to the embodiments without departing from the principles and spirit of the invention, and that the scope of the invention is defined by the claims and their equivalents.

[0114] The above is a specific description of the preferred implementation of the present invention, but the present invention is not limited to the embodiments. Those skilled in the art can make various equivalent modifications or substitutions without violating the spirit of the present invention. These equivalent modifications or substitutions are all included in the scope defined by the claims of this application.

Claims

1. A multi-system signal generation method, characterized in that: include: According to the signal generation instruction, the signal system type and signal parameters of the target signal are obtained; generating a control instruction sequence and modulation parameters according to the system type and the signal parameters, and generating target configuration parameters according to the signal modulation parameters; Modulating the original signal according to the control instruction and configuration parameters to obtain a modulated signal, wherein the modulation model is an intermediate baseband signal; Performing filtering and shaping processing on the modulated signal to obtain a target signal; A first analog signal input from the outside is obtained, and the target signal is converted into a second analog signal. The first analog signal and the second analog signal are collected, played back, and stored as sample signals.

2. The multi-system signal generation method according to claim 1, characterized in that: The step of obtaining the signal system type and signal parameters of the target signal according to the signal generation instruction includes: According to the signal generation instruction, an analytical algorithm is used to obtain the signal system type and signal parameters of the target signal, where the signal system type includes communication signals, radar signals and interference signals; the signal parameters include frequency range, bandwidth, modulation mode and coding type.

3. The multi-system signal generation method according to claim 2, wherein: The generating of the control instruction sequence and the modulation parameters according to the system type and the signal parameters includes: generating a control instruction sequence using an analytical algorithm according to the signal system type, querying an instruction library to obtain the control instruction sequence, and generating the modulation parameters according to the control instruction sequence; The control instruction sequence generated by the analytical algorithm is stored, and the analytical algorithm is optimized using the stored control instruction sequence.

4. The multi-system signal generation method according to claim 2, characterized in that: The step of modulating the original signal according to the control instruction and the configuration parameters to obtain a modulated signal includes: According to the signal system type, the corresponding modulation algorithm is used to perform modulation processing. When the signal system type is a communication signal, modulation mapping and shaping filtering processing are performed; when the signal system type is a radar signal, time domain modulation and frequency domain modulation processing are performed; when the signal system type is an interference signal, the interference strategy is dynamically modulated according to the characteristics of the interference signal.

5. The multi-system signal generation method according to claim 4, characterized in that: The filtering and shaping processing of the modulated signal to obtain a target signal includes: performing a spurious frequency removal process on the intermediate baseband signal according to the signal parameters, and then performing waveform optimization, wherein the waveform optimization includes aligning the spectral purity and waveform regularity of the intermediate baseband signal with those of the target signal to obtain an intermediate frequency signal; The intermediate frequency signal is converted to obtain the target signal.

6. The multi-system signal generation method according to claim 5, characterized in that: The step of acquiring a first analog signal input from an external source, converting the target signal into a second analog signal, and collecting, replaying, and storing the first analog signal and the second analog signal as sample signals includes: After the target signal is converted by DAC and sampled, a second analog signal is obtained, and the time-frequency spectrum and time-frequency parameters of the second analog signal are played back; The coupled signal input from the outside is sampled to obtain the first analog signal, the first analog signal and the second analog signal are subjected to signal detection and signal parameter estimation, and sample data is generated and stored.

7. A multi-system signal generating device for implementing the method according to any one of claims 1 to 6, characterized in that: include: A signal control module is used to obtain the signal system type and signal parameters of the target signal according to the signal generation instruction; Used to generate a control instruction sequence and modulation parameters according to the system type and the signal parameters, and to generate target configuration parameters according to the signal modulation parameters; A signal modulation generation module is used to modulate the original signal according to the control instruction and configuration parameters to obtain a modulated signal, wherein the modulation model is an intermediate baseband signal; A signal shaping conversion module, configured to filter and shape the modulated signal to obtain a target signal; The signal shaping and conversion module is further used to obtain a first analog signal input from an external source, and convert the target signal into a second analog signal; The signal shaping and conversion module is used to perform signal detection processing and signal parameter estimation on the first analog signal and the second analog signal in sequence to obtain sample data; The signal control module is used to play back the sample data; The data storage module is used to store sample data, baseband data and signal library.

8. The multi-system signal generating device according to claim 7, characterized in that: The signal control module adopts Feiteng D2000 CPU.

9. The multi-system signal generating device according to claim 7, characterized in that: The signal modulation generation module adopts Fudan Micro JFM9VU13P chip.

10. The multi-system signal generating device according to claim 7, characterized in that: The signal shaping and conversion module adopts Fudan Micro JFM9RFVU3P5G chip.

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