A signal processing method, system and electronic device based on microwave photon technology

Abstract

This application discloses a signal processing method, system, and electronic device based on microwave photonics technology, relating to the field of microwave photonics technology, which can improve the response speed of radar systems in detecting targets. The signal processing method based on microwave photonics technology is characterized by comprising: acquiring an optical carrier; modulating a radio frequency signal to be processed onto the optical carrier to obtain a first optical signal; adjusting the phase of the first optical signal to obtain a second optical signal; performing photoelectric conversion processing on the second optical signal to obtain a first electrical signal; performing matched filtering processing on the first electrical signal to generate a target electrical signal; and performing analog-to-digital conversion on the target electrical signal to obtain a digital signal.

Description

Technical Field

[0001] This application relates to the field of microwave photonics technology, and in particular to a signal processing method, system and electronic device based on microwave photonics technology. Background Technology

[0002] Microwave photonics technology is an interdisciplinary field combining microwave and optoelectronic technologies, organically integrating their advantages and demonstrating transformative capabilities in information domains such as radar, communications, and electronic warfare. With the rapid growth of information technology, radar systems are evolving towards higher resolution, wider bandwidth, and larger arrays. This dramatic increase in data volume presents a severe challenge to radar signal processing. However, existing signal processing methods, limited by the bandwidth, power consumption, and information processing speed of traditional electronic circuits, struggle to process large-bandwidth signals at high speeds, potentially slowing down the radar system's target detection response. Summary of the Invention

[0003] This application provides a signal processing method, system, and electronic device based on microwave photonics technology, which can improve the response speed of radar systems in detecting targets.

[0004] A first aspect of this application provides a signal processing method based on microwave photonics technology, comprising:

[0005] Acquire optical carrier;

[0006] The radio frequency signal to be processed is modulated onto the optical carrier to obtain a first optical signal;

[0007] The phase of the first optical signal is adjusted to obtain the second optical signal;

[0008] The second optical signal is subjected to photoelectric conversion processing to obtain the first electrical signal;

[0009] The first electrical signal is subjected to matched filtering to generate the target electrical signal;

[0010] The target electrical signal is converted from analog to digital to obtain a digital signal.

[0011] In some embodiments, adjusting the phase of the first optical signal includes:

[0012] The phase of the first optical signal is adjusted by regulating the dispersion of the optical waveguide, wherein the first optical signal is transmitted within the optical waveguide structure.

[0013] In some embodiments, the dispersion of the optical waveguide ranges from 0 to 4000 ps / nm.

[0014] In some embodiments, before performing photoelectric conversion processing on the second optical signal, the method further includes:

[0015] The second optical signal is frequency-converted; and / or,

[0016] After performing photoelectric conversion processing on the second optical signal, the method further includes:

[0017] The first electrical signal is subjected to frequency conversion processing.

[0018] In some embodiments, before performing photoelectric conversion processing on the second optical signal, the second optical signal is subjected to optical power amplification processing; and / or,

[0019] After the second optical signal undergoes photoelectric conversion processing, the first electrical signal undergoes electrical power amplification processing.

[0020] In some embodiments, after performing analog-to-digital conversion on the target electrical signal, the method further includes:

[0021] The target electrical signal is transmitted to the display terminal.

[0022] A second aspect of this application provides a signal processing system based on microwave photonics technology, comprising:

[0023] An optical signal source, wherein the optical signal source is used to output an optical carrier;

[0024] An electrical radio frequency signal source, wherein the electrical radio frequency signal source is used to output radio frequency signals;

[0025] An electro-optic modulator, wherein the optical input terminal of the electro-optic modulator is connected to the output terminal of an optical signal source, and the radio frequency input interface of the electro-optic modulator is connected to the output terminal of the electro-radio frequency signal source, and the electro-optic modulator is used to modulate the radio frequency signal onto an optical carrier to obtain a first optical signal;

[0026] A dispersion control module is provided, wherein the output of the electro-optic modulator is connected to the input of the dispersion control module, and the dispersion control module is used to adjust the phase of the first optical signal to obtain a second optical signal;

[0027] A photodetector, wherein the output of the dispersion control module is connected to the input of the photodetector, and the photodetector is used to convert the second optical signal into a first electrical signal;

[0028] A matched filter is provided, wherein the output of the photodetector is connected to the input of the matched filter, and the matched filter is used to perform matched filtering processing on the first electrical signal to obtain the target electrical signal;

[0029] An analog-to-digital converter module is provided, wherein the output of the matched filter is connected to the input of the analog-to-digital converter module, and the analog-to-digital converter module is used to convert the target electrical signal into an analog signal.

[0030] In some embodiments, the matched filter is a surface acoustic wave (SAW) filter, the bandwidth of which is the same as the bandwidth of the radio frequency (RF) signal; and / or, the pulse width of the SAW filter is the same as the pulse width of the RF signal.

[0031] In some embodiments, the signal processing system based on microwave photonics technology further includes:

[0032] A signal amplifier, comprising an optical signal amplifier and an electrical signal amplifier, wherein the optical signal amplifier is disposed between the dispersion control module and the photodetector; and / or,

[0033] The electrical signal amplifier is disposed between the photodetector and the filter;

[0034] A mixer, wherein the mixer is disposed between the dispersion control module and the optical signal amplifier; and / or,

[0035] The mixer is positioned between the dispersion control module and the electrical signal amplifier.

[0036] A third aspect of this application provides an electronic device, comprising:

[0037] The signal processing system based on microwave photonics technology as described in the second aspect.

[0038] The signal processing method based on microwave photonics technology provided in this application utilizes microwave photonics technology to achieve analog domain windowing processing of broadband radio frequency signals in the optical domain by controlling the dispersion of the dispersion control module, and uses a matched filter to achieve analog domain matched filtering processing of the broadband signals. This method can realize the integrated implementation of analog domain windowing and matched filtering, which can significantly reduce the signal processing pressure of the radar system's back-end, improve the radar system's target detection response speed and radar system resolution. Attached Figure Description

[0039] Figure 1 A schematic flowchart illustrating a signal processing method based on microwave photonics technology provided for the embodiments of the application;

[0040] Figure 2 A simulation diagram of a matched filter output provided for an embodiment of this application;

[0041] Figure 3 A schematic structural diagram of a signal processing system based on microwave photonics technology provided in this application embodiment;

[0042] Figure 4 A signal waveform diagram provided in an embodiment of this application;

[0043] Figure 5 Another signal waveform diagram provided in this application embodiment;

[0044] Figure 6 This application provides another signal waveform diagram.

[0045] Figure 7 Another signal waveform diagram provided in the embodiments of this application;

[0046] Figure 8 A simulation diagram of another matched filter output provided in an embodiment of this application;

[0047] Figure 9 This is a schematic structural diagram of an electronic device provided in an embodiment of this application. Detailed Implementation

[0048] To better understand the technical solutions provided in the embodiments of this specification, the technical solutions of the embodiments of this specification will be described in detail below with reference to the accompanying drawings and specific embodiments. It should be understood that the embodiments of this specification and the specific features in the embodiments are detailed descriptions of the technical solutions of the embodiments of this specification, rather than limitations on the technical solutions of this specification. In the absence of conflict, the embodiments of this specification and the technical features in the embodiments can be combined with each other.

[0049] In this document, relational terms such as "first" and "second" are used merely to distinguish one entity or operation from another, without necessarily requiring or implying any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element. The term "two or more" includes two or more cases.

[0050] Microwave photonics technology is an interdisciplinary field combining microwave and optoelectronic technologies, organically integrating their advantages and demonstrating transformative capabilities in information domains such as radar, communications, and electronic warfare. With the rapid growth of information technology, radar systems are evolving towards higher resolution, wider bandwidth, and larger arrays. This dramatic increase in data volume presents a severe challenge to radar signal processing. However, existing signal processing methods, limited by the bandwidth, power consumption, and information processing speed of traditional electronic circuits, struggle to process large-bandwidth signals at high speeds, potentially slowing down the radar system's target detection response.

[0051] In view of this, embodiments of this application provide a signal processing method, system, and electronic device based on microwave photonics technology, which can improve the response speed of radar systems in detecting targets.

[0052] In a first aspect, this application provides a signal processing method based on microwave photonics technology. Figure 1 This is a schematic flowchart illustrating a signal processing method based on microwave photonics technology, provided as an embodiment of the application. Figure 1 As shown, the detection methods include:

[0053] S101: Acquire optical carrier.

[0054] For example, an optical carrier is obtained through an optical signal source, which can be a single-frequency continuous laser, a quasi-continuous laser, or other laser that can output a continuous wave.

[0055] S102: Modulate the radio frequency signal to be processed onto the optical carrier to obtain the first optical signal.

[0056] For example, the radio frequency signal to be processed can be a linear frequency modulated signal output from an electro-RF signal source, or a broadband echo signal from a microwave photonic radar. Both the optical carrier and the radio frequency signal are transmitted to an electro-optic modulator, which modulates the radio frequency signal onto the optical carrier to obtain a first optical signal, which is an optical carrier radio frequency signal.

[0057] S103: Adjust the phase of the first optical signal to obtain the second optical signal.

[0058] For example, the first optical signal can be a periodic continuous wave. After being transmitted via the dispersion control module, the phase of the first optical signal changes, resulting in a second optical signal. The second optical signal is then beat-frequency transmitted via a photodetector. The phase-changed optical sidebands and the optical carrier undergo difference frequency processing. This phase difference leads to amplitude attenuation of the output electrical signal, causing a change in the amplitude of the first electrical signal output after beating by the photodetector, and further, a change in the power of the first electrical signal. The greater the phase difference between the first and second optical signals, the smaller the amplitude of the first electrical signal output by the first photodetector, the lower the power of the first electrical signal, and the more significant the attenuation of the first electrical signal.

[0059] For example, dispersion can cause phase differences in first optical signals of different frequencies. During photoelectric conversion, the photodetector beats the first optical signals with different phase differences, resulting in power differences in the first electrical signals of different frequencies, thus attenuating the power of the electrical signals at different frequencies. The greater the dispersion of the dispersion control module, the greater the phase difference of the second optical signals of different frequencies, and the greater the power difference of the first electrical signals of different frequencies output by the photodetector. By adjusting the dispersion of the dispersion control module, phase differences are caused in the second optical signals of different frequencies, and the photodetector beats the second optical signals with different phase differences, achieving different attenuation effects on the first electrical signals.

[0060] S104: Perform photoelectric conversion processing on the second optical signal to obtain the first electrical signal.

[0061] For example, the second optical signal is a periodic continuous wave. The second optical signal is transmitted to the photodetector. By adjusting the dispersion amount of the dispersion control module, the second optical signal with a changed phase is photoelectrically converted by the photodetector to form a first electrical signal with periodic power attenuation, thereby realizing windowing processing of the first electrical signal.

[0062] S105: Perform matched filtering on the first electrical signal to generate the target electrical signal.

[0063] For example, the first electrical signal is transmitted to a matched filter. Matched filtering of the first electrical signal enhances its signal-to-noise ratio (SNR) and compresses its pulse width, resulting in a target electrical signal with a narrower pulse width and a higher SNR. The target electrical signal can be a continuous wave with main lobes and side lobes. By adjusting the dispersion level of the dispersion control module, the suppression effect of side lobes on the target electrical signal can be enhanced. The greater the dispersion level of the dispersion control module, the lower the power of the first electrical signal after photoelectric conversion, and the stronger the suppression effect of side lobe amplitude after pulse compression by the matched filter. The dispersion control module can suppress the side lobe amplitude of the target electrical signal by applying first optical signals of different frequencies, causing the side lobe power to decay rapidly, reducing the interference of side lobes on the main lobe after pulse compression, and improving radar resolution, measurement accuracy, and speed.

[0064] S106: Perform analog-to-digital conversion on the target electrical signal to obtain a digital signal.

[0065] For example, the target electrical signal is an analog signal. After the target signal is transmitted to the analog-to-digital converter, the analog signal is converted into a digital signal by the analog-to-digital converter. By setting up windowing and matched filtering in the analog domain, the signal processing pressure in the radar digital domain can be reduced and the response speed of the radar system to detect targets can be improved.

[0066] Typically, microwave photonic radar echo signal processing methods involve the following steps: At the receiver, the echo signal received by the antenna is modulated onto an optical carrier via electro-optic conversion. The optical signal is then subjected to conventional microwave photonic superheterodyne / zero-IF reception. After spurious signals are filtered out by an optical filter, the demodulated electrical signal is recovered using a photoelectric conversion module. Subsequently, an intermediate frequency analog-to-digital converter (ADC) is performed for further analysis and processing in the digital domain. While this method is simple and intuitive in principle, its signal processing performance depends heavily on the performance of the microwave signal processing hardware used, and it suffers from slow processing speeds for large-bandwidth signals.

[0067] The signal processing method based on microwave photonics technology provided in this application utilizes microwave photonics technology to achieve analog domain windowing processing of broadband radio frequency signals in the optical domain by controlling the dispersion of the dispersion control module, and uses a matched filter to achieve analog domain matched filtering processing of the broadband signals. This method can realize the integrated implementation of analog domain windowing and matched filtering, which can significantly reduce the signal processing pressure of the radar system's back-end, improve the radar system's target detection response speed and radar system resolution.

[0068] In some implementations, step S103 further includes:

[0069] The phase of the first signal is adjusted by regulating the dispersion of the optical waveguide, wherein the first optical signal is transmitted within the optical waveguide structure.

[0070] For example, the dispersion control module is composed of an optical waveguide structure, which can be a dispersion control instrument, a dispersion fiber, or a combination of both. The dispersion control module can achieve the required dispersion level for the first optical signal. The greater the dispersion level of the dispersion control module, the stronger the sidelobe suppression effect of the target electrical signal generated by the subsequent matched filter. The dispersion level can be adjusted according to the radar system resolution and sidelobe suppression ratio required for the detection scenario. By setting the dispersion control module, the dispersion level can be precisely controlled, achieving precise control of the first signal power, thereby improving the radar system's resolution and detection accuracy.

[0071] In some implementations, the dispersion of the optical waveguide ranges from 0 to 4000 ps / nm.

[0072] For example, the dispersion control module is a dispersion-controlled optical fiber. The longer the dispersion-controlled optical fiber, the greater the dispersion of the dispersion control module, and the stronger the sidelobe suppression effect of the target electrical signal output through the matched filter. By adjusting the length of the optical fiber, the dispersion of the optical waveguide can be precisely controlled, so that the radar system can accurately detect the target object, thereby improving the radar detection resolution and accuracy.

[0073] Figure 2This is a simulation diagram of a matched filter output provided for an embodiment of this application. For example, as shown... Figure 2 As shown, the optical waveguide is a dispersive fiber. The dispersion of the optical waveguide is equal to the length of the dispersive fiber multiplied by the dispersion coefficient of the light. The dispersion can be adjusted by increasing the length of the fiber or by increasing the dispersion coefficient of the dispersive fiber. Figure 2 Curve S3 represents the waveform of the target electrical signal output through the matched filter when the optical waveguide dispersion coefficient is 100 ps / nm and the fiber length is 0 km. Curve S4 represents the waveform of the target electrical signal output through the matched filter when the optical waveguide dispersion coefficient is 100 ps / nm and the fiber length is 13.2 km. Curve S5 represents the waveform of the target electrical signal output through the matched filter when the optical waveguide dispersion coefficient is 100 ps / nm and the fiber length is 26 km. Curve S6 represents the waveform of the target electrical signal output through the matched filter when the optical waveguide dispersion coefficient is 100 ps / nm and the fiber length is 32.5 km. It can be seen that, for the same dispersion coefficient, the longer the fiber, the greater the dispersion of the dispersion control module, and the more obvious the sidelobe printing effect of the target electrical signal output through the matched filter. By controlling the length of the dispersion fiber, the dispersion of the optical waveguide can be precisely controlled, thereby improving the diversity of targets detected by the radar detection system.

[0074] For example, the dispersion control module can be a dispersion control instrument, which controls the dispersion of the optical waveguide by adjusting the dispersion parameters in the dispersion control instrument. By configuring the dispersion control instrument, the space occupied by the dispersion control module can be reduced, thereby improving the space utilization of the radar equipment.

[0075] In some embodiments, before step S104, the method further includes: performing frequency conversion processing on the second optical signal. After step S104, the method further includes: performing frequency conversion processing on the first electrical signal.

[0076] For example, frequency conversion processing of the second optical signal can be performed by transmitting the second optical signal to a mixer, where the mixer reduces the frequency of the second optical signal so that its frequency matches the frequency of the matched filter. Frequency conversion processing of the first electrical signal can also be performed by reducing the frequency of the first electrical signal so that its frequency matches the frequency of the matched filter. By performing frequency conversion processing before the photoelectric conversion processing of the second optical signal, or after the photoelectric conversion processing of the first electrical signal, the frequency of either the first optical signal or the first electrical signal can be reduced so that its frequency matches the frequency of the matched filter. This avoids signal mismatch during the matched filtering process, which could affect pulse compression and lead to radar detection errors.

[0077] In some embodiments, before step S104, the method further includes: performing optical power amplification on the second optical signal. After step S104, the method further includes: performing electrical power amplification on the first electrical signal.

[0078] For example, power amplification of the second optical signal can be performed by transmitting the frequency-converted second optical signal to an optical signal amplifier after frequency conversion processing to amplify its power, or by directly amplifying the optical power of the second optical signal output from the dispersion control module. Similarly, power amplification of the first electrical signal can be performed by transmitting the frequency-converted first electrical signal to an electrical signal amplifier after frequency conversion processing to amplify its power, or by directly amplifying the power of the first electrical signal output from the photodetector. By amplifying the optical power before photoelectric conversion processing of the frequency-converted second optical signal, or by amplifying the electrical power after photoelectric conversion processing of the frequency-converted first electrical signal, the losses incurred during frequency conversion processing of both the second optical signal and the first electrical signal can be mitigated, preventing excessively low signal-to-noise ratios that could cause the radar detection system to fail to detect the target.

[0079] In some implementations, after step S105, the method further includes: transmitting the target electrical signal to the display terminal.

[0080] For example, the display terminal can be a monitor or a digital signal processor for further signal processing. The display terminal can perform further data analysis on the target signal to enable the radar system to detect the target. By setting the windowing and matched filtering processing of the radio frequency signal in the analog domain, when the radio frequency signal enters the optical domain, the processing of the wideband radio frequency signal is performed in real time, reducing the pressure on the digital domain data processing of the display terminal and improving the response speed of the radar system.

[0081] A second aspect of this application provides a signal processing system based on microwave photonics technology. Figure 3 This is a schematic structural diagram of a signal processing system based on microwave photonics technology provided in an embodiment of this application.

[0082] For example, such as Figure 3As shown, the signal processing system for microwave photonics technology includes an optical signal source 100, an electro-RF signal source 200, an electro-optic modulator 300, a dispersion control module 400, a photodetector 500, a matched filter 600, and an analog-to-digital converter 700. The optical input interface of the electro-optic modulator 300 is connected to the output interface of the optical signal source 100, and the RF input interface of the electro-optic modulator 300 is connected to the output interface of the electro-RF signal source 200. The output interface of the electro-optic modulator 300 is connected to the input interface of the dispersion control module 400; the electro-optic modulator 300 can be a quadrature biased electro-optic modulator. The output interface of the dispersion control module 400 is connected to the input interface of the photodetector 500, and the output interface of the photodetector 500 is connected to the input interface of the matched filter 600. The output interface of the matched filter 600 is connected to the input interface of the analog-to-digital converter 700. An optical signal source is used to output an optical carrier, and an electro-RF signal source 200 is used to output an RF signal. An electro-optic modulator 300 modulates the RF signal onto the optical carrier to obtain a first optical signal, which is an optical carrier RF signal. The first optical signal is transmitted to a dispersion compensation module. By adjusting the dispersion amount of the dispersion compensation module, the phase of the first optical signal at different frequencies is changed to obtain a second optical signal. The second optical signal is transmitted to a photodetector 500 for photoelectric conversion, converting the second optical signal into a first electrical signal. The first electrical signal is transmitted to a matched filter 600 for matched filtering. After matched filtering, the pulse of the first electrical signal is compressed to obtain the target electrical signal. The height of the main lobe and side lobes of the target electrical signal output by the matched filter is further suppressed, greatly reducing the influence of the side lobes on the main lobe.

[0083] In some implementations, such as Figure 3 As shown, the output of the analog-to-digital converter (ADC) 700 is connected to the input of the display terminal 800. The ADC 700 can be implemented based on an electrical ADC 700 or a microwave photonic ADC 700. It can convert analog signals to digital signals and vice versa, enabling diverse signal processing capabilities to adapt to different data processing methods of the display terminal.

[0084] To facilitate understanding, the technical solution of the present invention will be further described in detail below from a theoretical perspective.

[0085] The continuous optical signal output by optical signal source 100 is given by equation (1):

[0086] (1)

[0087] in, and These are the amplitude and center frequency of the optical carrier, respectively. This is the expression for a continuous optical signal.

[0088] The radio frequency signal output by the radio frequency signal source 200, taking the linear frequency modulated signal as an example, can be expressed as equation (2):

[0089] (2)

[0090] in, , , These are the amplitude, center frequency, and modulation slope of the linear frequency modulated signal, respectively. Taking an orthogonally biased electro-optic modulator as an example, the first optical signal output by the electro-optic modulator 300 can be expressed as equation (3):

[0091] (3)

[0092] in, Represents a rectangle function. For radio frequency signal pulse width, This is the first-order expansion of the Bessel function. It is the modulation coefficient of MZM (electro-optic modulator). It is the half-wave voltage of the MZM. A rectangular function is used to... Perform multiplication to obtain .

[0093] The first optical signal is affected by the dispersion in the dispersion control module 400. The dispersion control module 400 outputs the second optical signal into the photodetector 500, which generates a first electrical signal with a windowing effect through photoelectric conversion. The spectrum of the first electrical signal can be expressed as Equation (4):

[0094] (4)

[0095] in, The center wavelength of the optical carrier. and These represent the dispersion coefficient and length of the dispersion fiber built into the dispersion control module.

[0096] Taking a surface acoustic wave matched filter as an example, the response function of the matched filter 600 can be expressed as equation (5):

[0097] (5)

[0098] Based on the frequency response function of the surface acoustic wave matched filter, the first electrical signal is subjected to frequency domain matched filtering. The output spectrum after matched filtering can be expressed as Equation (6), and the time domain waveform can be expressed as Equation (7).

[0099] (6)

[0100] (7)

[0101] (8)

[0102] in, and , and These are the error function and the virtual error function, respectively. Equation (7) It is derived from equation (6). Equation (8), obtained through the inverse Fourier transform, is an approximation of (7). In equation (8)... Let be the error function. Let B be the virtual error function, and let B be the bandwidth of the first electrical signal. c The speed of light. This is obtained using the error function and the virtual error function. The approximate solution. According to equation (7), the dispersion-induced power attenuation will be reflected in the height of the sidelobes of the matched filter output waveform.

[0103] Figure 4 This application provides a signal waveform diagram as an embodiment. Figure 5 This is another signal waveform diagram provided in an embodiment of this application. Figure 6 This is yet another signal waveform diagram provided in the embodiments of this application. Figure 7 This is another signal waveform diagram provided in the embodiments of this application. Figure 8 This is a simulation diagram of another matched filter output provided in an embodiment of this application.

[0104] For example, Figure 4 and Figure 6 The horizontal axis "Time" represents time, measured in microseconds (µs), while the vertical axis "Amplitude" represents amplitude, measured in volts (V). For example... Figure 4 As shown, when the dispersion control module is not working, the waveform of the first electrical signal has a horizontal axis ranging from -4µs to 6µs, a pulse width of 10µs in the time domain, an amplitude of 0.15V, and a noise amplitude of 0.05V. Figure 6 As shown, the dispersion control module operates at a dispersion of 2145 ps / nm. The waveform of the first electrical signal has an abscissa of -5 µs to 5 µs, a pulse width of 10 µs in the time domain, an amplitude of 0.17 V, and a noise amplitude of 0.05 V. Therefore, it can be seen that after passing through the dispersion control module, the peak power of the main lobe of the first electrical signal increases, while the peak power of the side lobes decreases, thus achieving the generation of a windowed radio frequency signal after photoelectric conversion.

[0105] For example, Figure 5 and Figure 7 The horizontal axis, Frequency, represents frequency in GHz (megahertz), while the vertical axis, Amplitude, represents amplitude in dBmV (decibels and millivolts). Figure 8 The horizontal axis represents time, in μs (microseconds), and the vertical axis represents amplitude, in dB (decibels). Figure 5 When the dispersion control module is not working, the waveform of the first electrical signal has an abscissa of 1.2 GHz to 2.2 GHz, a bandwidth of 1 GHz in the frequency domain, and a relatively flat spectrum. Figure 7 When the dispersion control module is working, the waveform of the first electrical signal has an abscissa of 1.2 GHz to 2.2 GHz, and the bandwidth of the first electrical signal in the frequency domain is 1 GHz. Due to the influence of dispersion, the power of the first electrical signal gradually decreases from the center frequency to both sides.

[0106] For example, the waveform of formula (7) is as follows: Figure 8 As shown in S2, dispersion-induced power attenuation is reflected in the height of the sidelobes of the matched filter output waveform. Figure 4 As shown, the time-domain waveform of the first electrical signal when the dispersion control module is not working is as follows. Figure 5 The figure shows the frequency domain waveform of the first electrical signal when the dispersion control module is not working. Figure 8 Curve S1 represents the waveform of the target electrical signal output by the surface acoustic wave filter when the dispersion control module is not operating. Figure 6 As shown, the time-domain waveform of the first electrical signal is as follows, with the dispersion control module operating at a dispersion of 2145 ps / nm. Figure 7 The image shows the frequency domain waveform of the first electrical signal when the dispersion control module is operating at a dispersion of 2145 ps / nm. The waveform is shown when the dispersion control module is not operating. Figure 8 S2 is the waveform of the target electrical signal output by the surface acoustic wave filter when the dispersion control module is working. Comparing curves S1 and S2, when the dispersion control module is working, the power attenuation of the side lobes of curve S2 is significantly lower than that of the main lobe. By adjusting the dispersion amount of the dispersion control module, the side lobes of the target electrical signal output by the surface acoustic wave filter are significantly suppressed.

[0107] For example, Figures 4 to 7 All are the first electrical signals before matched filtering, and the pulse width of the first electrical signals is 10µs. Figure 8 The target electrical signal S2 is processed by a surface acoustic wave filter with matched filtering. The horizontal axis of the target electrical signal S2 is from -0.3ns to 0.7ns, and the pulse width of the target electrical signal is 1ns. By setting the matched filtering process, the pulse compression of the target electrical signal can be achieved, thereby improving the resolution of radar detection.

[0108] The signal processing system based on microwave photonics technology provided in this application utilizes microwave photonics technology to achieve analog domain windowing processing of broadband radio frequency signals in the optical domain by controlling the dispersion of the dispersion control module, and uses a matched filter to achieve analog domain matched filtering processing of broadband signals. This method can realize the integrated implementation of analog domain windowing and matched filtering, which can significantly reduce the signal processing pressure of the radar system's back-end, improve the radar system's target detection response speed and radar system resolution.

[0109] In some implementations, the filter is a surface acoustic wave (SAW) filter. The bandwidth of the SAW filter is the same as the bandwidth of the radio frequency (RF) signal, and the pulse width of the SAW filter is the same as the pulse width of the RF signal. By matching the parameters of the SAW filter and the RF signal, the SAW filter can better achieve pulse compression, thereby improving the detection accuracy and response speed of the radar system.

[0110] For example, the surface acoustic wave (SAW) filter has a bandwidth of 1 GHz and a pulse width of 10 μs. The SAW filter's frequency modulation slope is equal to the ratio of bandwidth to pulse width. The SAW filter is matched with the frequency modulation slope of the radio frequency (RF) signal, which has a bandwidth of 1 GHz and a pulse width of 10 μs. By matching the parameters of the SAW filter with the RF signal, the SAW filter can better achieve pulse compression, improving the detection accuracy and response speed of the radar system.

[0111] In some implementations, the signal processing system based on microwave photonics technology further includes a signal amplifier and a mixer. The signal amplifier includes an optical signal amplifier and an electrical signal amplifier; the optical signal amplifier is positioned between the dispersion control module and the photodetector, and the electrical signal amplifier is positioned between the photodetector and the matched filter. The mixer can be positioned between the dispersion control module and the optical signal amplifier, or it can be positioned between the photodetector and the electrical signal amplifier.

[0112] For example, the mixer can be positioned between the dispersion control module and the optical signal amplifier. The first optical signal passes through the dispersion control module to obtain a second optical signal. This second optical signal is first frequency-converted by the mixer, and then amplified by the optical signal amplifier. Alternatively, the mixer can be positioned between the photodetector and the matched filter. The second optical signal passes through the photodetector to obtain a first electrical signal. This first electrical signal is first frequency-converted by the mixer, and then amplified by the power output of the frequency-converted first electrical signal.

[0113] It should be noted that a mixer can perform frequency conversion processing on optical signals, and a mixer can also perform frequency conversion processing on electrical signals. A signal processing system of microwave photonics technology can be equipped with one mixer or multiple mixers. The purpose is to reduce the frequency of the signal to the frequency suppression of the matched filter. This application does not make a specific limit on the number of mixers.

[0114] This application embodiment performs frequency conversion processing on the first electrical signal before photoelectric conversion processing of the second optical signal, or performs frequency conversion processing on the first electrical signal after photoelectric conversion processing. This reduces the signal frequency so that it matches the frequency of the matched filter, thus avoiding matching distortion during the matched filtering process, which could affect pulse compression and lead to radar detection errors.

[0115] For example, an optical signal amplifier can be placed between the dispersion control module and the photodetector to directly amplify the optical power of the second optical signal. Alternatively, the optical signal amplifier can be placed between the mixer and the photodetector to amplify the optical power of the frequency-converted second optical signal. An electrical signal amplifier can be placed between the photodetector and the matched filter to directly amplify the power of the first electrical signal, or between the photodetector and the mixer to amplify the electrical power of the frequency-converted first electrical signal. By amplifying the optical power before the photoelectric conversion of the frequency-converted second optical signal, or by amplifying the electrical power after the photoelectric conversion of the frequency-converted first electrical signal, the signal loss during the frequency conversion process can be mitigated, preventing the main lobe and side lobe power from being too low, which could cause the radar detection system to fail to detect the target.

[0116] For example, a signal processing system for microwave photonics technology can be implemented based on discrete devices, or it can be integrated with chips or modules and discrete devices to facilitate the integration of the signal processing system for microwave photonics technology.

[0117] A third aspect of this application is to provide an electronic device. Figure 9 This is a schematic structural diagram of an electronic device provided in an embodiment of this application, such as... Figure 9 As shown, the electronic device 1000 includes a signal processing system 2000 based on microwave photonics technology as described in the second aspect, forming a radar detection device.

[0118] The electronic device provided in this application uses microwave photonics technology to achieve analog domain windowing processing of broadband radio frequency signals in the optical domain by regulating the dispersion of the dispersion control module, and uses a matched filter to achieve analog domain matched filtering processing of broadband signals. This method can realize the integrated implementation of analog domain windowing and matched filtering, which can significantly reduce the signal processing pressure of the radar system backend, improve the response speed of radar detection equipment to targets, and improve the resolution of radar detection equipment.

[0119] It should be noted that the descriptions of each embodiment in the above embodiments have different focuses. For parts that are not described in detail in a certain embodiment, please refer to the relevant descriptions in other embodiments.

[0120] The above embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this application.

[0121] Although preferred embodiments have been described in this specification, those skilled in the art, upon learning the basic inventive concept, can make other changes and modifications to these embodiments. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments as well as all changes and modifications falling within the scope of this specification.

[0122] Obviously, those skilled in the art can make various modifications and variations to this specification without departing from its spirit and scope. Therefore, if such modifications and variations fall within the scope of the claims and their equivalents, this specification is also intended to include such modifications and variations.

Claims

1. A signal processing method based on microwave photonics technology, characterized in that, include: Acquire optical carrier; The radio frequency signal to be processed is modulated onto the optical carrier to obtain a first optical signal; The phase of the first optical signal is adjusted to obtain the second optical signal; The second optical signal is subjected to photoelectric conversion processing to obtain the first electrical signal; The first electrical signal is subjected to matched filtering to generate the target electrical signal; The target electrical signal is converted from analog to digital to obtain a digital signal; Adjusting the phase of the first optical signal includes: The phase of the first optical signal is adjusted by adjusting the dispersion of the optical waveguide, wherein the first optical signal is transmitted within the optical waveguide structure; By adjusting the dispersion of the optical waveguide, the second optical signal, whose phase changes, is processed by photoelectric conversion through a photodetector to form the first electrical signal with periodic power attenuation, thereby achieving windowing processing of the first electrical signal. The target electrical signal is a continuous wave with a main lobe and side lobes. By adjusting the dispersion, the suppression effect of the side lobes of the target electrical signal is enhanced.

2. The signal processing method of microwave photonics technology according to claim 1, characterized in that, The dispersion of the optical waveguide ranges from 0 to 4000 ps / nm.

3. The signal processing method of microwave photonics technology according to claim 1, characterized in that, Before performing photoelectric conversion processing on the second optical signal, the method further includes: The second optical signal is frequency-converted; and / or, After performing photoelectric conversion processing on the second optical signal, the method further includes: The first electrical signal is subjected to frequency conversion processing.

4. The signal processing method of microwave photonics technology according to claim 3, characterized in that, Before performing photoelectric conversion processing on the second optical signal, the second optical signal undergoes optical power amplification processing; and / or, After the second optical signal undergoes photoelectric conversion processing, the first electrical signal undergoes electrical power amplification processing.

5. The signal processing method of microwave photonics technology according to claim 1, characterized in that, After performing analog-to-digital conversion on the target electrical signal, the method further includes: The target electrical signal is transmitted to the display terminal.

6. A signal processing system based on microwave photonics technology, characterized in that, include: An optical signal source, wherein the optical signal source is used to output an optical carrier; An electrical radio frequency signal source, wherein the electrical radio frequency signal source is used to output radio frequency signals; An electro-optic modulator, wherein the optical input interface of the electro-optic modulator is connected to the output interface of the optical signal source, and the radio frequency input interface of the electro-radio frequency signal source is connected to the output interface of the electro-radio frequency signal source, and the electro-optic modulator is used to modulate the radio frequency signal onto an optical carrier to obtain a first optical signal; A dispersion control module is provided, wherein the output interface of the electro-optic modulator is connected to the input interface of the dispersion control module, and the dispersion control module is used to adjust the phase of the first optical signal to obtain a second optical signal; A photodetector, wherein the output interface of the dispersion control module is connected to the input interface of the photodetector, and the photodetector is used to convert the second optical signal into a first electrical signal; A matched filter is provided, wherein the output interface of the photodetector is connected to the input interface of the matched filter, and the matched filter is used to perform matched filtering processing on the first electrical signal to obtain the target electrical signal; An analog-to-digital converter module is provided, wherein the output interface of the matched filter is connected to the input interface of the analog-to-digital converter module, and the analog-to-digital converter module is used to convert the target electrical signal into an analog signal.

7. The signal processing system based on microwave photonics technology according to claim 6, characterized in that, The matched filter is a surface acoustic wave (SAW) filter, and the bandwidth of the SAW filter is the same as the bandwidth of the radio frequency (RF) signal; and / or, the pulse width of the SAW filter is the same as the pulse width of the RF signal.

8. The signal processing system based on microwave photonics technology according to claim 6, further comprising: A signal amplifier, comprising an optical signal amplifier and an electrical signal amplifier, wherein the optical signal amplifier is disposed between the dispersion control module and the photodetector; and / or, The electrical signal amplifier is disposed between the photodetector and the filter; A mixer, wherein the mixer is disposed between the dispersion control module and the optical signal amplifier; and / or, The mixer is positioned between the dispersion control module and the electrical signal amplifier.

9. An electronic device, comprising: The signal processing system based on microwave photonics technology as described in any one of claims 6 to 8.

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