Narrow pulse modulation signal generation device and method

Abstract

The invention discloses a narrow pulse modulation signal generation device and method. The device is characterized by comprising a baseband digital signal simulation module, a digital interface control module and a radio frequency waveform generation module which are connected in sequence, wherein the baseband digital signal simulation module is used for outputting I-path and Q-path serial baseband waveform data; the digital interface control module is used for reading baseband waveform data, controlling sampling rate parameters and writing the baseband waveform data into the radio frequency waveform generation module; the radio frequency waveform generation module is used for converting a baseband digital signal into a narrow pulse modulation signal and comprises a controller, a waveform memory, a serial-to-parallel converter, a local clock and a digital-to-analog converter, the controller is responsible for sending a control instruction, and the waveform memory is used for storing baseband waveform data. The system can transmit two paths of information at the same time, has the characteristics of high precision, high stability and flexible control, and meets the complex signal processing requirements in the fields of modern radars, communication and the like.

Description

Technical Field

[0001] The present invention relates to the field of electronic technology, and in particular to a device and method for generating a narrow pulse modulation signal. Background Art

[0002] Narrow pulse signals have extremely short pulse widths. Due to their high time resolution, they can accurately measure the distance, speed, and direction of a target, and are often used in radar systems to detect and track target information. Narrow pulse modulated signals show significant advantages under high frequency and complex channel conditions. Through spectrum expansion technology, narrow pulse modulated signals can expand the original signal to a wider frequency band to transmit information, effectively improving the signal's anti-interference ability and maintaining good communication quality in complex electromagnetic environments. In addition, narrow pulse modulated signals usually have lower power density and are less susceptible to adjacent frequency interference than traditional signals.

[0003] Although narrow pulse signals have demonstrated excellence in many fields, there are still some technical challenges in generating arbitrary narrow pulse modulation signals with pulse widths ranging from nanoseconds to microseconds. In the time domain, since narrow pulse signals usually have very short durations, generating such signals requires very precise timing control and fast response capabilities; in the frequency domain, narrow pulse signals have broadband characteristics, requiring broadband signal processing devices and algorithms to ensure the accuracy and integrity of the signal, involving high-speed analog circuit design and broadband digital signal processing technology; in the process of DAC converting narrow pulse signals, extremely high resolution and output accuracy are required to ensure that the converted analog signal can fully express the subtle characteristics and rapid changes of the narrow pulse. The traditional method of directly generating narrow pulse modulation signals from microwave signal sources, due to the limitations of ADC performance, the maximum sampling rate is insufficient, which limits the pulse width range of the modulated signal that can be generated.

[0004] Chinese patent document 97100054.9 discloses a modulated narrow pulse generating device. The device provides a compensation method for the input signal, delay circuit, interception circuit and modulation circuit, so that the obtained modulated narrow pulse signal meets the bandwidth requirement in the radar altimeter system. Compared with the invention, the present invention provides a baseband digital signal simulation module, which is based on the method for generating narrow pulse modulated signals in the digital domain, and can generate narrow pulse baseband signals by changing the digital waveform, and has higher flexibility and strong scalability.

[0005] Chinese patent application 201010275503.1 proposes a technology for obtaining ultra-wideband narrow pulses by using software radio, and adopts a method of truncating some special functions to generate narrow pulse time domain waveforms that meet the requirements by programmable devices. Compared with the invention, the present invention provides a radio frequency waveform generation module, which is combined with a digital interface control module to simulate the output of digital signals, and has an accurate clock control system, which can realize accurate control of pulse signals and has higher accuracy and stability.

[0006] The Chinese paper "Ultra-Wideband Ultra-Narrow Pulse Design and Generation" discloses a method of using transistor avalanche characteristics, using parallel and simultaneous triggering to design and generate a high repetition rate UWB pulse circuit generator, and analyzes and calculates the characteristic parameters of the pulse from the perspective of the equivalent circuit method. Compared with this technology, the narrow pulse modulation signal generation device provided by the present invention is based on digital IQ modulation technology. Since the I-channel and Q-channel signals are orthogonal in phase, they can transmit information independently without interfering with each other. Therefore, within the same bandwidth, two channels of information can be transmitted simultaneously, which is equivalent to doubling the spectrum utilization while maintaining high transmission quality and stability. Summary of the invention

[0007] To solve the above problems, the present invention provides a high-precision, high-stability, and flexibly controlled narrow pulse modulation signal generation device and method to meet the complex signal processing requirements in modern radar and communication fields, while introducing digital IQ modulation technology to take into account both data generation quality and transmission efficiency, and fully consider factors such as the sampling rate, storage and transmission capabilities, signal processing capabilities, and synchronization and triggering capabilities of hardware equipment.

[0008] The present invention provides a narrow pulse modulation signal generating device, characterized in that it comprises a baseband digital signal simulation module, a digital interface control module, and a radio frequency waveform generating module which are connected in sequence.

[0009] The baseband digital signal simulation module is used to generate and adjust the baseband digital signal, thereby generating a narrow pulse signal with the required specific frequency, pulse width and waveform characteristics, and outputting I-channel and Q-channel serial baseband waveform data;

[0010] The digital interface control module is used to manage digital signals and control the RF waveform generation module, read baseband waveform data, control sampling rate parameters, and write baseband waveform data into the RF waveform generation module;

[0011] The RF waveform generation module is used to convert the baseband digital signal generated by the baseband digital signal simulation module into a narrow pulse modulation signal, and includes a controller, a waveform memory, a serial-to-parallel converter, a local clock, and a digital-to-analog converter. The controller is responsible for issuing control instructions, and the waveform memory is used to store the baseband waveform data; the serial-to-parallel converter is used to convert serial I-channel and Q-channel baseband waveform data into parallel baseband waveform data; the DAC converts the calculated baseband waveform data into an analog signal; and the local clock is used to provide the synchronization clock and sampling clock signals required to generate the waveform.

[0012] Furthermore, the baseband digital signal simulation module includes a module installed with Matlab software, and the baseband digital signal is generated and adjusted by using Matlab software.

[0013] Furthermore, the baseband digital signal simulation module generates a .txt or .mat data file through simulation, the digital interface control module provides a digital input of a narrow pulse signal, and imports the .txt or .mat data file generated by the baseband digital signal simulation module into the RF waveform generation module to ensure the consistency of the simulation data with the actual generated signal in terms of timing and frequency.

[0014] Furthermore, the digital interface control module includes a module installed with dedicated signal control software, which is connected to the RF waveform generation module based on the LAN bus, reads the baseband pulse waveform data, and monitors the time domain and frequency domain characteristics of the waveform, ensures that the read waveform data is correct, controls the sampling rate parameters, and writes the waveform data into the RF waveform generation module.

[0015] Furthermore, the radio frequency waveform generation module is composed of a radio frequency signal recording and playback device.

[0016] Furthermore, one end of the waveform memory is connected to the digital interface control module, and the other end is connected to the serial-to-parallel converter; one end of the serial-to-parallel converter is connected to the waveform memory, and the other end outputs two parallel baseband pulse waveform data, one is the in-phase component signal I(n), and the other is the orthogonal component signal Q(n); the in-phase component signal and the orthogonal component signal are modulated by the local clock IQ respectively and then added, and then the added digital signal is input into the digital-to-analog converter; the digital-to-analog converter outputs a radio frequency pulse modulation signal; and the controller is implemented by a dedicated digital signal processor (DSP).

[0017] The present invention also provides a method for generating a narrow pulse modulation signal, characterized in that it uses the above-mentioned narrow pulse modulation signal generating device and comprises the following steps:

[0018] S1. Generate a baseband pulse signal through a baseband digital signal simulation module, output I-channel and Q-channel serial baseband waveform data, the two-channel signals are orthogonal, and the simulation modeling of the baseband pulse signal is completed;

[0019] S2, reading the baseband waveform data through the digital interface control module, and monitoring the time domain and frequency domain characteristics of the waveform, ensuring the read waveform data, controlling the sampling rate parameters, and writing the baseband waveform data into the RF waveform generation module;

[0020] S3, generating a continuous pulse modulation waveform through a radio frequency waveform generation module, including:

[0021] The baseband pulse waveform data outputted by the waveform memory is outputted as parallel in-phase component I(n) and quadrature component Q(n) after being converted by a serial-to-parallel converter;

[0022] The local clock performs phase control on the in-phase component I(n) and the quadrature component Q(n) respectively, and the phase-controlled results are added to obtain the digital signal S(n);

[0023] The digital signal S(n) is converted into a narrow pulse modulated analog signal S(t) by the digital-to-analog converter DAC.

[0024] Furthermore, in step S1, the baseband pulse signal is composed of a high level and a low level, which is used to represent binary information. The baseband pulse signal has a very clear rising edge and falling edge, and a stable level duration.

[0025] The baseband pulse signal a(t) is defined as follows:

[0026]

[0027] Among them, T1 is the pulse signal width, T2 is the interval between pulses, that is, the pulse period, and t is the time parameter; T1 / T2 is called the duty cycle of the pulse signal. The duty cycle of a narrow pulse signal is less than 50%. The narrower the pulse signal width T1, the wider the corresponding frequency band; the wider the pulse signal width T1, the narrower the corresponding frequency band.

[0028] Furthermore, in step S3, assuming that the real part of the pulse signal is a, the imaginary part is b, ω c is the carrier angular frequency, t is the time parameter, then the process of up-conversion of the baseband pulse signal is:

[0029]

[0030] Taking the real part of the up-converted signal gives the IQ modulated signal, as shown in formula (3):

[0031]

[0032] The two channels of orthogonal data obtained by simulation are represented by I(n) and Q(n) respectively. According to formula (3), the IQ modulated digital signal is:

[0033]

[0034] Among them, ω c is the carrier angular frequency, ω s is the sampling angular frequency, f c is the carrier frequency, f s is the sampling rate, n is the number of sampling points;

[0035] Assume 2πf c / f=Δω, then formula (4) can be expressed as:

[0036] S(n)=I(n)×cos(Δωn)-Q(n)×sin(Δωn)(5)

[0037] After passing through DAC, it becomes analog signal output.

[0038] S(t)=I(t)×cos(ω c t)-Q(n)×sin(ω c t)(6).

[0039] Furthermore, the baseband pulse signal in step S1 satisfies the Nyquist sampling theorem, and the sampling frequency is greater than twice the highest frequency of the signal.

[0040] The invention provides a narrow pulse modulation signal generating device and method based on digital IQ modulation technology, which can transmit two channels of information at the same time, has the characteristics of high precision, high stability and flexible control, and meets the complex signal processing requirements in modern radar, communication and other fields.

[0041] Compared with the prior art, the present invention has the following beneficial effects:

[0042] (1) Accurate pulse control: The RF waveform generation module provided by the present invention provides a synchronous clock and a sampling clock signal, which can ensure stable waveform frequency and phase control, and realize accurate control of the pulse width, amplitude and repetition frequency.

[0043] (2) High temporal resolution: The narrow pulse modulation signal generation device and verification provided by the present invention has a very wide bandwidth and can generate and analyze short-duration pulses with extremely high temporal resolution, which is particularly important for signal scenarios that require rapid response or simulation of rapidly changing signals.

[0044] (3) Adjustable output characteristics: The baseband digital signal simulation module provided by the present invention has high flexibility. Users can adjust the signal parameter output characteristics of the narrow pulse generation module as needed to simulate signal conditions under different conditions.

[0045] (4) Stability and reliability: The present invention is designed with long-term stability and reliability in mind. The DAC has very high DA conversion accuracy. Moreover, based on digital IQ modulation technology, it can ensure the accuracy and consistency of the output signal during long-term operation.

[0046] (5) Wide range of applications: The narrow pulse modulation signal generation module provided by the present invention can be applied to a variety of application fields, including timing and synchronization in communication systems. It can also be used to measure characteristics such as the delay of communication channels. In signal simulation, equipment testing, radar system evaluation, and communication system performance verification, it can not only ensure that each device maintains an accurate time reference during data transmission and processing; it is also very important for optimizing channel design and adjustment. BRIEF DESCRIPTION OF THE DRAWINGS

[0047] In order to more clearly illustrate the technical solutions disclosed in the present invention, the following briefly introduces the drawings required to be used in some embodiments disclosed in the present invention. Obviously, the drawings described below are only drawings of some embodiments disclosed in the present invention. For ordinary technicians in this field, other drawings can also be obtained based on these drawings. In addition, the drawings described below can be regarded as schematic diagrams, and are not limitations on the actual size of the products involved in the embodiments disclosed in the present invention, the actual process of the method, etc.

[0048] Figure 1 It is a schematic diagram of the hardware for generating the narrow pulse modulation signal provided by the present invention.

[0049] Figure 2 It is a schematic diagram of the hardware composition of the narrow pulse modulation signal generating device provided by the present invention.

[0050] Figure 3 It is a schematic diagram of the working principle of the radio frequency waveform generation module provided by the present invention.

[0051] Figure 4 This is a flow chart of generating a narrow pulse modulation signal provided by the present invention.

[0052] Figure 5 It is the time domain waveform of the narrow pulse waveform (50ns pulse width) generated by the baseband digital simulation module.

[0053] Figure 6 It is a frequency domain waveform of a narrow pulse waveform (50ns pulse width) generated by the baseband digital simulation module.

[0054] Figure 7 It is the time domain waveform read by the baseband digital interface control module.

[0055] Figure 8 It is the frequency domain waveform monitored by the baseband digital interface control module after reading the time domain waveform.

[0056] Fig. 9 This is the verification result of the narrow pulse modulation signal generating device provided by the present invention (pulse width 50ns). DETAILED DESCRIPTION

[0057] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0058] In the present application, LAN means local area network; I(n) means in-phase component; Q(n) means quadrature component; S(n) means digital signal; DAC means digital-to-analog converter; S(t) means narrow pulse modulated analog signal.

[0059] Figure 1 Schematic diagram of the hardware for generating the narrow pulse modulation signal provided by the present invention. Figure 1 As shown, a narrow pulse modulation signal generating device provided by the present invention includes a baseband digital signal simulation module, a digital interface control module, and a radio frequency waveform generating module, and the baseband digital signal simulation module, the digital interface control module, and the radio frequency waveform generating module are connected in sequence. The present invention generates baseband pulse waveform data through the baseband digital signal simulation module, uses the radio frequency waveform generating module and the digital interface control module to move the waveform data to radio frequency, combines modern digital signal processing technology to convert the waveform data into an analog signal, and optimizes the design of the system architecture including high-speed clock synchronization and high-speed sampling mechanism, so as to realize the accurate generation of narrow pulse signals.

[0060] Figure 2 Schematic diagram of the hardware composition of the narrow pulse modulation signal generating device provided by the present invention. Figure 2 As shown, the baseband digital signal simulation module includes a computer and Matlab software, which is the basis of high-quality narrow pulse signals. The digital interface control module includes a computer and dedicated signal control software, which is a bridge for the generation of narrow pulse modulation signals. The RF waveform generation module is composed of an RF signal recording and playback instrument, which is the core component of the narrow pulse modulation signal generation device.

[0061] The baseband digital signal simulation module generates and adjusts the baseband digital signal by using the Matlab software, thereby generating a narrow pulse signal with the required specific frequency, pulse width and waveform characteristics. The baseband digital signal simulation module generates a .txt or .mat data file through simulation. The baseband digital signal simulation module outputs baseband waveform data.

[0062] The digital interface control module is used to manage digital signals and control the RF waveform generation module. The digital interface control module provides digital input of narrow pulse signals, imports the .txt or .mat data files generated by the baseband digital signal simulation module into the RF waveform generation module, and ensures the consistency of the simulation data with the actual generated signal in terms of timing and frequency, thereby ensuring the accuracy and reliability of subsequent experiments or applications.

[0063] The radio frequency waveform generation module is used to convert the baseband digital signal generated by the baseband digital signal simulation module into a narrow pulse modulation signal.

[0064] Figure 3 FIG. 1 is a schematic diagram showing the working principle of the RF waveform generation module provided by the present invention. Figure 3 As shown, the RF waveform generation module includes a controller (not shown), a waveform memory, a serial-to-parallel converter, a local clock, and a digital-to-analog converter (DAC). The controller is responsible for issuing control instructions, which are implemented by a dedicated digital signal processor (DSP).

[0065] One end of the waveform memory is connected to the digital interface control module, and the other end is connected to the serial-to-parallel converter, and is used to store the baseband waveform data generated by the baseband digital signal simulation module.

[0066] One end of the serial-to-parallel converter is connected to the waveform memory, and the other end outputs two parallel baseband pulse waveform data, one is the in-phase component signal I(n), and the other is the orthogonal component signal Q(n), which is used to convert the serial I and Q baseband waveform data into parallel baseband waveform data.

[0067] The local clock is used to provide the synchronization clock and sampling clock signal required for waveform generation, and to provide stable waveform frequency and phase control. The in-phase component signal and the orthogonal component signal are added after being modulated by the local clock IQ, and then the added digital signal is input into the digital-to-analog converter.

[0068] The digital-to-analog converter outputs a radio frequency pulse modulation signal. The DAC converts the calculated baseband waveform data into an analog signal, and the DA conversion accuracy is high.

[0069] The present invention also provides a method for generating a narrow pulse modulation signal, firstly, generating baseband pulse waveform data through Matlab software simulation; then, through digital interface control, the baseband pulse waveform data output by the Matlab software is imported into a radio frequency waveform generation module, and then a continuous narrow pulse modulation waveform is generated through the radio frequency waveform generation module. The method for generating a narrow pulse modulation signal of the present invention generates baseband pulse waveform data through the baseband digital signal simulation module, and uses the digital interface control module and the radio frequency waveform generation module to move the waveform data to radio frequency, thereby realizing the accurate generation of a narrow pulse signal.

[0070] Figure 4 This is a flow chart of the generation of the narrow pulse modulation signal provided by the present invention. Figure 4 As shown, Figure 4 As shown, the method of the present invention specifically comprises the following steps:

[0071] S1. Simulate and generate baseband pulse signals to complete simulation modeling of baseband pulse signals

[0072] The baseband digital signal simulation module simulates the baseband pulse signal through Matlab software, and outputs the baseband waveform data of I and Q serial channels, the two channels of signals are orthogonal, and the data format is .txt or .mat format;

[0073] The baseband pulse signal is composed of a high level and a low level, and is used to represent binary information. Ideally, the baseband pulse signal has a very clear rising edge and falling edge, and a stable level duration;

[0074] The baseband pulse signal a(t) is defined as follows:

[0075]

[0076] Among them, T1 is the pulse signal width, T2 is the interval between pulses, that is, the pulse period, and t is the time parameter; T1 / T2 is called the duty cycle of the pulse signal, and the duty cycle of a narrow pulse signal is less than 50%.

[0077] The narrower the pulse signal width T1, the wider the corresponding frequency band; the wider the pulse signal width T1, the narrower the corresponding frequency band.

[0078] According to formula (1), the baseband pulse signal is simulated. The simulated signal, i.e., the baseband pulse signal, satisfies the Nyquist sampling theorem. The sampling frequency is greater than twice the highest frequency of the signal, so as to retain the complete information of the signal without distortion. Here, the baseband waveform data of I-channel and Q-channel serial are simulated and generated. The two-channel signals are orthogonal, and the data format is .txt or mat format.

[0079] S2. Read baseband waveform data through the digital interface control module

[0080] The digital interface control module is connected to the RF waveform generation module based on a local area network (LAN) bus, reads baseband waveform data, and monitors the time domain and frequency domain characteristics of the waveform to ensure the read waveform data, control the sampling rate parameters, and write the baseband waveform data into the RF waveform generation module.

[0081] S3. Generate a continuous pulse modulation waveform through the RF waveform generation module

[0082] The radio frequency waveform generation module is composed of a radio frequency signal recording and playback device.

[0083] The baseband pulse waveform data output by the waveform memory is output as a parallel in-phase component I(n) and a quadrature component Q(n) after a serial-to-parallel converter, and the local clock performs phase control on the in-phase component I(n) and the quadrature component Q(n) respectively, and the phase-controlled results are added to obtain an analog signal S(n).

[0084] The digital signal S(n) is converted into a narrow pulse modulated analog signal S(t) by the digital-to-analog converter (DAC). Theoretically, assuming that the real part of the pulse signal is a and the imaginary part is b, ω c is the carrier angular frequency, t is the time parameter, then the process of up-conversion of the baseband pulse signal is:

[0085]

[0086] Taking the real part of the up-converted signal gives the IQ modulated signal, as shown in formula (3):

[0087]

[0088] In the actual circuit, the two channels of orthogonal data obtained by simulation are represented by I(n) and Q(n) respectively. According to formula (3), the IQ modulated digital signal is:

[0089]

[0090] Among them, ω c is the carrier angular frequency, ω s is the sampling angular frequency, f c is the carrier frequency, f s is the sampling rate, and n is the number of sampling points.

[0091] Assume 2πf c / f=Δω, then formula (4) can be expressed as:

[0092] S(n)=I(n)×cos(Δωn)-Q(n)×sin(Δωn)(5)

[0093] After passing through DAC, it becomes analog signal output.

[0094] S(t)=I(t)×cos(ω c t)-Q(n)×sin(ω c t)(6)

[0095] As mentioned above, according to the Nyquist sampling theorem, the sampling rate is at least twice the highest frequency of the sampled signal. Narrow pulse signals have more high-frequency components. When the rising edge of the pulse signal is very short, it is necessary to select a sufficiently high sampling rate to ensure that the transient changes of the signal can be accurately captured. Therefore, the present invention selects a device with a very high sampling rate, and the device can read and output IQ baseband data, control the carrier frequency of the signal radio frequency through a digital interface control module, and complete up-conversion and digital-to-analog conversion, and perform spectrum shifting of the pulse signal through orthogonal modulation to achieve radio frequency output. The present invention is based on the above principles.

[0096] Measurement verification of narrow pulse waveforms

[0097] The narrow pulse signal is measured using a pulse measuring device to verify the performance of the narrow pulse modulation signal generating device provided by the present invention.

[0098] By using the method provided by the present invention, a radio frequency signal recording and playback device with a higher sampling rate can be selected, so that a pulse signal with a narrower pulse width of ns level can be generated. The following table shows the test results of the embodiment:

[0099] Serial number Nominal pulse width (ns) Pulse width measured value (ns) error 1 50 50.02 0.4‰ 2 100 97.57 -2.5％ 3 200 198.2 -9.0‰ 4 500 499.9 -0.2‰ 5 1000 997.8 -0.22％ 6 2000 1997 -0.15％

[0100] Figure 5 The figure shows the time domain waveform of the narrow pulse waveform generated by the baseband digital simulation module in the embodiment of the present invention, with a pulse width of 50ns; Figure 6 The figure shows the frequency domain waveform of the narrow pulse waveform generated by the baseband digital simulation module in the embodiment of the present invention, with a pulse width of 50ns; Figure 7 Shown is a time domain waveform read by the baseband digital interface control module in an embodiment of the present invention; Figure 8 The figure shows the frequency domain waveform monitored by the baseband digital interface control module after reading the time domain waveform in the embodiment of the present invention; Fig. 9 The figure shows the verification result of the narrow pulse modulation signal generating device provided in the embodiment of the present invention, and the pulse width is 50ns. Figures 5 to 9 As shown, the pulse measurement equipment is used to measure the generated continuous pulse modulation wave. The experimental results show that the device and method provided by the present invention can generate a narrow pulse signal with a pulse width as low as 50ns. The measurement result is 50.02ns, and the measurement error is 0.4‰, which has a high accuracy. Figures 5 to 9 As shown:

[0101] Although the present invention has been disclosed as above in the form of a preferred embodiment, it is not intended to limit the present invention. Any person skilled in the art may make possible changes and modifications to the technical solution of the present invention using the above disclosed contents without departing from the spirit and scope of the present invention. Therefore, any simple modifications, equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention without departing from the contents of the technical solution of the present invention shall fall within the protection scope of the technical solution of the present invention.

Claims

1. A narrow pulse modulation signal generating device, characterized in that: It includes a baseband digital signal simulation module, a digital interface control module, and a radio frequency waveform generation module connected in sequence. The baseband digital signal simulation module is used to generate and adjust the baseband digital signal, thereby generating a narrow pulse signal with the required specific frequency, pulse width and waveform characteristics, and outputting I-channel and Q-channel serial baseband waveform data; The digital interface control module is used to manage digital signals and control the RF waveform generation module, read baseband waveform data, control sampling rate parameters, and write baseband waveform data into the RF waveform generation module; The RF waveform generation module is used to convert the baseband digital signal generated by the baseband digital signal simulation module into a narrow pulse modulation signal, and includes a controller, a waveform memory, a serial-to-parallel converter, a local clock, and a digital-to-analog converter. The controller is responsible for issuing control instructions, and the waveform memory is used to store the baseband waveform data; The serial-to-parallel converter is used to convert the serial I-channel and Q-channel baseband waveform data into parallel baseband waveform data; The DAC converts the calculated baseband waveform data into an analog signal; the local clock is used to provide a synchronization clock and a sampling clock signal required to generate the waveform.

2. A narrow pulse modulation signal generating device according to claim 1, characterized in that: The baseband digital signal simulation module includes a module installed with Matlab software, and generates and adjusts the baseband digital signal by using the Matlab software.

3. The narrow pulse modulation signal generating device according to claim 1, characterized in that: The baseband digital signal simulation module generates a .txt or .mat data file through simulation, and the digital interface control module provides a digital input of a narrow pulse signal. The .txt or .mat data file generated by the baseband digital signal simulation module is imported into the RF waveform generation module to ensure the consistency of the simulation data with the actual generated signal in terms of timing and frequency.

4. The narrow pulse modulation signal generating device according to claim 1, characterized in that: The digital interface control module includes a module installed with dedicated signal control software, which is connected to the RF waveform generation module based on the LAN bus, reads the baseband pulse waveform data, and monitors the time domain and frequency domain characteristics of the waveform. On the basis of ensuring that the read waveform data is correct, it controls the sampling rate parameters and writes the waveform data into the RF waveform generation module.

5. The narrow pulse modulation signal generating device according to claim 1, characterized in that: The radio frequency waveform generation module is composed of a radio frequency signal recording and playback device.

6. The narrow pulse modulation signal generating device according to claim 1, characterized in that: One end of the waveform memory is connected to the digital interface control module, and the other end is connected to the serial-to-parallel converter; one end of the serial-to-parallel converter is connected to the waveform memory, and the other end outputs two parallel baseband pulse waveform data, one is the in-phase component signal I(n), and the other is the orthogonal component signal Q(n); the in-phase component signal and the orthogonal component signal are modulated by the local clock IQ respectively and then added, and then the added digital signal is input into the digital-to-analog converter; The digital-to-analog converter outputs a radio frequency pulse modulation signal; and the controller is implemented by a dedicated digital signal processor DSP.

7. A method for generating a narrow pulse modulation signal, characterized in that: The narrow pulse modulation signal generating device according to any one of claims 1 to 6 comprises the following steps: S1. Generate a baseband pulse signal through a baseband digital signal simulation module, output I-channel and Q-channel serial baseband waveform data, the two-channel signals are orthogonal, and the simulation modeling of the baseband pulse signal is completed; S2, reading the baseband waveform data through the digital interface control module, and monitoring the time domain and frequency domain characteristics of the waveform, ensuring the read waveform data, controlling the sampling rate parameters, and writing the baseband waveform data into the RF waveform generation module; S3, generating a continuous pulse modulation waveform through a radio frequency waveform generation module, including: The baseband pulse waveform data outputted by the waveform memory is outputted as parallel in-phase component I(n) and quadrature component Q(n) after being converted by a serial-to-parallel converter; The local clock performs phase control on the in-phase component I(n) and the quadrature component Q(n) respectively, and the phase-controlled results are added to obtain the digital signal S(n); The digital signal S(n) is converted into a narrow pulse modulated analog signal S(t) by the digital-to-analog converter DAC.

8. A method for generating a narrow pulse modulation signal according to claim 7, characterized in that: In step S1, the baseband pulse signal is composed of a high level and a low level, and is used to represent binary information. The baseband pulse signal has a very clear rising edge and falling edge, and a stable level duration. The baseband pulse signal a(t) is defined as follows: Among them, T1 is the pulse signal width, T2 is the interval between pulses, that is, the pulse period, and t is the time parameter; T1 / T2 is called the duty cycle of the pulse signal. The duty cycle of a narrow pulse signal is less than 50%. The narrower the pulse signal width T1, the wider the corresponding frequency band; the wider the pulse signal width T1, the narrower the corresponding frequency band.

9. A method for generating a narrow pulse modulation signal according to claim 8, characterized in that: In step S3, it is assumed that the real part of the pulse signal is a, the imaginary part is b, ω c is the carrier angular frequency, t is the time parameter, then the process of up-conversion of the baseband pulse signal is: Taking the real part of the up-converted signal gives the IQ modulated signal, as shown in formula (3): The two channels of orthogonal data obtained by simulation are represented by I(n) and Q(n) respectively. According to formula (3), the IQ modulated digital signal is: Among them, ω c is the carrier angular frequency, ω s is the sampling angular frequency, f c is the carrier frequency, f s is the sampling rate, n is the number of sampling points; Assume 2πf c / f=Δω, then formula (4) can be expressed as: S(n)=I(n)×cos(Δωn)-Q(n)×sin(Δωn) (5) After passing through DAC, it becomes analog signal output. S(t)=I(t)×cos(ω c t)-Q(n)×sin(ω c t) (6)。 10. The method for generating a narrow pulse modulation signal according to claim 7, characterized in that: The baseband pulse signal in step S1 satisfies the Nyquist sampling theorem, and the sampling frequency is greater than twice the highest frequency of the signal.

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