Signal processing method and system based on microwave photon technology, and electronic equipment

Abstract

The invention discloses a signal processing method and system based on a microwave photon technology, and electronic equipment, relates to the technical field of microwave photons, and can improve the response speed of a radar system for detecting a target. The signal processing method based on the microwave photon technology is characterized by comprising the following steps: acquiring an optical carrier wave; modulating a radio frequency signal to be processed on an 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 electric signal; performing matched filtering processing on the first electric signal to generate a target electric signal; and performing analog-to-digital conversion on the target electric signal to obtain a digital signal.

Description

Technical Field

[0001] The present application relates to the field of microwave photonic technology, and in particular to a signal processing method, system and electronic equipment based on microwave photonic technology. Background Art

[0002] Microwave photonics technology lies at the intersection of microwave and optoelectronics technologies. By combining the strengths of both, it has demonstrated transformative potential in information technology fields such as radar, communications, and electronic warfare. With the advancement of information technology, radar systems are evolving towards higher resolution, wider bandwidth, and larger arrays. The rapidly increasing volume of data presents significant challenges for 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 high-bandwidth signals at high speed, potentially impacting the radar system's response time in detecting targets. Summary of the Invention

[0003] The embodiments of the present application provide a signal processing method, system, and electronic device based on microwave photonic technology, which can improve the response speed of a radar system in detecting targets.

[0004] A first aspect of the embodiments of the present application provides a signal processing method based on microwave photonic technology, comprising:

[0005] Obtaining an optical carrier;

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

[0007] adjusting the phase of the first optical signal to obtain a second optical signal;

[0008] Performing photoelectric conversion on the second optical signal to obtain a first electrical signal;

[0009] performing matched filtering on the first electrical signal to generate a target electrical signal;

[0010] The target electrical signal is subjected to analog-to-digital conversion 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 adjusting the dispersion amount of the optical waveguide, wherein the first optical signal is transmitted in 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 on the second optical signal, the method further includes:

[0015] performing frequency conversion processing on the second optical signal; and / or,

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

[0017] Perform frequency conversion processing on the first electrical signal.

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

[0019] After the second optical signal is subjected to photoelectric conversion, the first electrical signal is subjected to electrical power amplification.

[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 a display terminal.

[0022] A second aspect of the embodiments of the present application provides a signal processing system based on microwave photonic technology, comprising:

[0023] an optical signal source, the optical signal source being used to output an optical carrier;

[0024] an electrical radio frequency signal source, the electrical radio frequency signal source being configured to output a radio frequency signal;

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

[0026] a dispersion control module, wherein the output of the electro-optical 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, 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 a target electrical signal;

[0029] An analog-to-digital conversion module, wherein the output of the matched filter is connected to the input of the analog-to-digital conversion module, and the analog-to-digital conversion 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 filter, the bandwidth of the surface acoustic wave filter is the same as the bandwidth of the radio frequency signal; and / or the pulse width of the surface acoustic wave filter is the same as the pulse width of the radio frequency signal.

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

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

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

[0034] a mixer, the mixer being arranged between the dispersion control module and the optical amplifier; and / or,

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

[0036] According to a third aspect of the present application, an electronic device is provided, including:

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

[0038] The signal processing method based on microwave photonic technology provided in the embodiments of the present application utilizes microwave photonic technology to implement analog domain windowing processing of broadband RF signals by regulating the dispersion of a dispersion control module in the optical domain, and utilizes a matched filter to implement analog domain matched filtering processing of the broadband signal. This method can realize the integrated implementation of analog domain windowing and matched filtering, which can significantly reduce the back-end signal processing pressure of the radar system and improve the response speed of the radar system in detecting targets and the resolution of the radar system. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] Figure 1 A schematic flow chart of a signal processing method based on microwave photonic technology provided in an embodiment of the application;

[0040] Figure 2 A simulation diagram of a matched filter output provided in an embodiment of the present application;

[0041] Figure 3 A schematic structural diagram of a signal processing system based on microwave photonic technology provided in an embodiment of the present application;

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

[0043] Figure 5 Another signal waveform diagram provided in an embodiment of the present application;

[0044] Figure 6 Another signal waveform diagram provided in an embodiment of the present application;

[0045] Figure 7 Another signal waveform diagram provided in an embodiment of the present application;

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

[0047] Figure 9 A schematic structural diagram of an electronic device provided in an embodiment of the present application. DETAILED DESCRIPTION

[0048] In order to better understand the technical solutions provided by the embodiments of this specification, the technical solutions of the embodiments of this specification are described in detail below through 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 article, relational terms such as first and second are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply the existence of any such actual relationship or order between these entities or operations. Moreover, the terms "comprise", "include" or any other variants thereof are intended to cover non-exclusive inclusion, so that the process, method, article or equipment comprising a series of elements includes not only those elements, but also other elements not explicitly listed, or also include elements inherent to such process, method, article or equipment. In the absence of further restrictions, the elements defined by the statement "comprising a ..." do not exclude the presence of other identical elements in the process, method, article or equipment comprising the elements. The term "two or more" includes two or more than two cases.

[0050] Microwave photonics technology lies at the intersection of microwave and optoelectronics technologies. By combining the strengths of both, it has demonstrated transformative potential in information technology fields such as radar, communications, and electronic warfare. With the advancement of information technology, radar systems are evolving towards higher resolution, wider bandwidth, and larger arrays. The rapidly increasing volume of data presents significant challenges for 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 high-bandwidth signals at high speed, potentially impacting the radar system's response time in detecting targets.

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

[0052] In a first aspect, the present application provides a signal processing method based on microwave photonic technology. Figure 1 The following is a schematic flow chart of a signal processing method based on microwave photonic technology provided in the embodiment of the application. Figure 1 As shown, the detection method includes:

[0053] S101: Acquire an optical carrier.

[0054] Exemplarily, the optical carrier is obtained through an optical signal source, which may 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 an optical carrier to obtain a first optical signal.

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

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

[0058] Exemplarily, the first optical signal can be a periodic continuous wave. After the first optical signal is transmitted through the dispersion control module, the phase of the first optical signal changes to obtain a second optical signal. The second optical signal is subjected to beat frequency through a photodetector, and the optical sideband with phase change is subjected to difference frequency processing with the optical carrier. The difference in phase difference will cause the amplitude of the output electrical signal to attenuate, causing the amplitude of the first electrical signal output after the beat frequency through the photodetector to change, and further the power of the first electrical signal to change. The greater the phase difference between the first optical signal and the second optical signal, the smaller the amplitude of the first electrical signal output through the first photodetector, the lower the power of the first electrical signal, and the more obvious the attenuation of the first electrical signal.

[0059] Exemplarily, the dispersion amount can cause phase differences in first optical signals of different frequencies. During the photoelectric conversion process, the phase differences in the first optical signals of different frequencies are beat by the photodetector, and the power differences of the first electrical signals of different frequencies are obtained, thereby achieving attenuation of the power of electrical signals of different frequencies. The greater the dispersion amount of the dispersion control module, the greater the difference in phase change of the second optical signals of different frequencies, and the greater the power difference in the first electrical signals of different frequencies output by the photodetector. By adjusting the dispersion amount of the dispersion control module, the second optical signals of different frequencies are caused to produce phase differences, and the photodetector beats the second optical signals of different phase differences, thereby achieving different attenuation effects on the first electrical signal.

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

[0061] Exemplarily, the second optical signal is a periodic continuous wave, and the second optical signal is transmitted to a photodetector. By adjusting the dispersion amount of the dispersion control module, the second optical signal with a changed phase is subjected to photoelectric conversion processing 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 a target electrical signal.

[0063] Exemplarily, the first electrical signal is transmitted to a matched filter, and the matched filter performs matched filtering on the first electrical signal, thereby enhancing the signal-to-noise ratio of the first electrical signal and compressing the pulse width of the first electrical signal to obtain a target electrical signal with a narrow pulse width and a large signal-to-noise ratio. The target electrical signal can be a continuous wave having a main lobe and side lobes. By adjusting the dispersion amount of the dispersion control module, the suppression effect of the side lobes of the target electrical signal can be enhanced. The greater the dispersion amount of the dispersion control module, the lower the power of the first electrical signal after the photoelectric conversion processing, and the stronger the suppression effect of the side lobe amplitude of the target electrical signal after the matched filter pulse compression. The dispersion control module can suppress the side lobe amplitude of the target electrical signal for first optical signals of different frequencies, causing the power of the side lobes to decay rapidly, reducing the interference of the side lobes of the target electrical signal after pulse compression on the main lobe, and improving the resolution and measurement accuracy of the radar.

[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 through the analog-to-digital converter. By integrating 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 in detecting targets can be improved.

[0066] Typically, microwave photon radar echo signal processing methods involve modulating the echo signal received by the antenna onto an optical carrier through electro-optical conversion at the receiving end. Conventional microwave photon superheterodyne / zero-IF reception is then performed on the optical signal. After an optical filter filters out spurious signals, the demodulated electrical signal is restored using an optoelectronic conversion module. IF analog-to-digital conversion (ADC) is then performed for further analysis and processing in the digital domain. While this method is straightforward in principle, its signal processing performance depends on the performance of the microwave signal processing hardware used, leading to slow processing speeds for wide-bandwidth signals.

[0067] The signal processing method based on microwave photonic technology provided in the embodiments of the present application utilizes microwave photonic technology to implement analog domain windowing processing of broadband RF signals by regulating the dispersion of a dispersion control module in the optical domain, and utilizes a matched filter to implement analog domain matched filtering processing of the broadband signal. This method can realize the integrated implementation of analog domain windowing and matched filtering, which can significantly reduce the back-end signal processing pressure of the radar system and improve the response speed of the radar system in detecting targets and the resolution of the radar system.

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

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

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

[0071] In some embodiments, the optical waveguide has a dispersion amount ranging from 0 to 4000 ps / nm.

[0072] Exemplarily, the dispersion control module is a dispersive optical fiber. The longer the dispersive optical fiber, the greater the dispersion of the dispersion control module, and the stronger the sidelobe suppression effect of the target electrical signal output by the matched filter. By adjusting the length of the optical fiber, the dispersion of the optical waveguide can be precisely controlled, allowing the radar system to accurately detect target objects and improving radar detection resolution and accuracy.

[0073] Figure 2This is a simulation diagram of a matched filter output provided in an embodiment of the present application. For example, Figure 2 As shown, the optical waveguide is a dispersive optical fiber. The dispersion of the optical waveguide is equal to the length of the dispersive optical fiber multiplied by the light dispersion coefficient. The dispersion can be adjusted by increasing the length of the optical fiber or by increasing the dispersion coefficient of the dispersive optical fiber. Figure 2 Curve S3 in the middle 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. This shows that, for the same optical fiber dispersion coefficient, the longer the fiber length, the greater the dispersion of the dispersion control module, and the more pronounced the sidelobe printing effect of the target electrical signal output through the matched filter. By controlling the length of the dispersive fiber, the dispersion of the optical waveguide can be precisely controlled, thereby improving the diversity of target detection by the radar detection system.

[0074] For example, the dispersion control module can be a dispersion control instrument. The dispersion of the optical waveguide is controlled 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 implementations, 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] Exemplarily, frequency conversion processing of the second optical signal may include transmitting the second optical signal to a mixer, and reducing the frequency of the second optical signal through the mixer so that the frequency of the second optical signal is the same as the frequency of the matched filter. Frequency conversion processing of the first electrical signal may include reducing the frequency of the first electrical signal so that the frequency of the first electrical signal is the same as the frequency of the matched filter. By performing frequency conversion processing before performing photoelectric conversion processing on the second optical signal, or performing frequency conversion processing on the first electrical signal after photoelectric conversion processing, the frequency of the first optical signal or the first electrical signal can be reduced so that the frequency of the first electrical signal is the same as the frequency of the matched filter, thereby avoiding signal mismatch during the matched filtering process, affecting the implementation of pulse compression, and causing radar detection errors.

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

[0078] Exemplarily, power amplification of the second optical signal may be performed by, after frequency conversion of the second optical signal, transmitting the frequency-converted second optical signal to an optical signal amplifier and amplifying the power of the frequency-converted second optical signal, or by directly performing optical power amplification on the second optical signal output by the dispersion control module. Electrical power amplification of the first electrical signal may be performed by, after frequency conversion of the first electrical signal, transmitting the frequency-converted first electrical signal to an electrical amplifier and amplifying the power of the frequency-converted first electrical signal, or by directly performing electrical power amplification on the first electrical signal output by the photodetector. By performing optical power amplification before performing photoelectric conversion on the frequency-converted second optical signal, or by performing electrical power amplification after performing photoelectric conversion on the frequency-converted first electrical signal, the loss of the second optical signal and the first electrical signal during the frequency conversion process can be reduced, thereby avoiding a low signal-to-noise ratio that causes 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 a display terminal.

[0080] For example, the display terminal can be a display or a digital signal processor for further signal processing. The display terminal can further analyze the target signal to enable the radar system to detect the target. By performing windowing and matched filtering on the RF signal in the analog domain, the wideband RF signal can be processed in real time when it enters the optical domain, reducing the pressure on the display terminal to process data in the digital domain and improving the response speed of the radar system.

[0081] A second aspect of the embodiments of the present application provides a signal processing system using microwave photonic technology. Figure 3 A schematic structural diagram of a signal processing system based on microwave photonic technology provided in an embodiment of the present application.

[0082] For example, Figure 3As shown, the signal processing system for microwave photonics technology includes an optical signal source 100, an electrical / RF signal source 200, an electro-optical modulator 300, a dispersion control module 400, a photodetector 500, a matched filter 600, and an analog-to-digital conversion module 700. The optical input interface of the electro-optical modulator 300 is connected to the output interface of the optical signal source 100, and the radio frequency input interface of the electro-optical modulator 300 is connected to the output interface of the electrical / RF signal source 200. The output interface of the electro-optical modulator 300 is connected to the input interface of the dispersion control module 400. The electro-optical modulator 300 can be a quadrature-biased electro-optical modulator. The output interface of the dispersion control module 400 is connected to the input interface of the photodetector 500, which 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 conversion module 700. The optical signal source is used to output an optical carrier, and the electrical RF signal source 200 is used to output an RF signal. The electro-optical modulator 300 can modulate the RF signal on the optical carrier to obtain a first optical signal, which is an optically carried RF signal. The first optical signal is transmitted to the dispersion compensation module. By adjusting the dispersion amount of the dispersion compensation module, the phase of the first optical signal of different frequencies is changed to obtain a second optical signal. The second optical signal is transmitted to the photodetector 500 for photoelectric conversion, and the second optical signal is converted into a first electrical signal. The first electrical signal is transmitted to the matched filter 600 for matched filtering processing. After the first electrical signal is processed by 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 impact of the side lobes on the main lobe.

[0083] In some embodiments, as Figure 3 As shown, the output of the analog-to-digital conversion module 700 is connected to the input of the display terminal 800. The analog-to-digital conversion module 700 can be implemented based on an electrical analog-to-digital conversion module 700 or a microwave-photonic analog-to-digital conversion module 700. It can convert analog signals into digital signals and vice versa, thus achieving diverse signal processing capabilities and adapting to data processing methods of different display terminals.

[0084] For ease of understanding, the technical solution of the present invention is further described in detail below from a theoretical perspective.

[0085] The continuous optical signal output by the optical signal source 100 is expressed as formula (1):

[0086]

[0087] Among them, E0 and f c are the amplitude and center frequency of the optical carrier, is the expression of the continuous light signal.

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

[0089] V(t)=V RF cos(2πf0t+πKt 2 ) (2)

[0090] Among them, V RF , f0, and K are the amplitude, center frequency, and frequency modulation slope of the linear frequency modulation signal, respectively. Taking the orthogonal biased electro-optical modulator as an example, the first optical signal output by the electro-optical modulator 300 can be expressed as formula (3):

[0091]

[0092] in, rect() represents the rectangular function, T is the RF signal pulse width, J1 is the first-order expansion of the Bessel function, is the modulation coefficient of the MZM (electro-optic modulator), V π is the half-wave voltage of MZM. Perform multiplication to get E out (t).

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

[0094]

[0095] Where λ is the center wavelength of the optical carrier, D and L are the dispersion coefficient and length of the dispersion fiber built into the dispersion control module, respectively.

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

[0097]

[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 spectrum output after matched filtering can be expressed as formula (6), and the time domain waveform can be expressed as formula (7):

[0099]

[0100]

[0101]

[0102] in, and erf(x) and erfi(x) are the error function and imaginary error function respectively. 1out (t) is given by formula (6) 1out (f) is obtained by inverse Fourier transform. Equation (8) is an approximate formula of (7). In Equation (8), erf(x) is the error function, erfi(x) is the imaginary error function, B is the bandwidth of the first electrical signal, and c is the speed of light. Using the error function and the imaginary error function, we can get S 1out 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 A signal waveform diagram provided in an embodiment of the present application, Figure 5 Another signal waveform diagram provided in an embodiment of the present application is: Figure 6 Another signal waveform diagram provided in an embodiment of the present application is: Figure 7 Another signal waveform diagram provided in an embodiment of the present application is: Figure 8 A simulation diagram of another matched filter output provided in an embodiment of the present application.

[0104] For example, Figure 4 and Figure 6 The horizontal axis Time represents the time, the unit is us (microseconds), and the vertical axis Amplitude represents the amplitude, the unit is V (volt). Figure 4 As shown in FIG, when the dispersion control module is not working, the horizontal coordinate of the waveform of the first electrical signal is -4us to 6us, the pulse width of the first electrical signal in the time domain is 10us, the amplitude of the first electrical signal is 0.15V, and the noise amplitude of the first electrical signal is 0.05V. Figure 6 As shown, when the dispersion control module operates at a dispersion of 2145 ps / nm, the abscissa of the waveform of the first electrical signal ranges from -5 µs to 5 µs, the pulse width of the first electrical signal in the time domain is 10 µs, the amplitude of the first electrical signal is 0.17 V, and the noise amplitude of the first electrical signal is 0.05 V. This shows that after passing through the dispersion control module, the mainlobe peak power of the first electrical signal increases, while the sidelobe peak power decreases, achieving a windowed RF signal after photoelectric conversion.

[0105] For example, Figure 5 and Figure 7 The horizontal axis Frequency represents the frequency, and the unit is GHz (megahertz), and the vertical axis Amplitude represents the amplitude, and the unit is dBmv (decibel millivolt). Figure 8The 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 horizontal axis of the waveform diagram of the first electrical signal is from 1.2 GHz to 2.2 GHz, the bandwidth of the first electrical signal in the frequency domain is 1 GHz, and the spectrum of the first electrical signal is relatively flat. Figure 7 When the characterized dispersion control module is working, the horizontal axis of the waveform diagram of the first electrical signal is 1.2 GHz to 2.2 GHz, the bandwidth of the first electrical signal in the frequency domain is 1 GHz, and the power of the first electrical signal gradually attenuates from the center frequency to both sides due to the influence of the dispersion amount.

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

[0107] For example, Figures 4 to 7 Both are first electrical signals before matched filtering, and the pulse width of the first electrical signals is 10us. Figure 8 The target electrical signal S2 is processed by the surface acoustic wave filter matched filtering. The horizontal coordinate of the target electrical signal S2 is -0.3ns to 0.7ns, and the pulse width of the target electrical signal is 1ns. Through the setting of matched filtering processing, 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 photonic technology provided in the embodiments of the present application utilizes microwave photonic technology to implement analog domain windowing processing of broadband RF signals by regulating the dispersion of a dispersion control module in the optical domain, and utilizes a matched filter to implement analog domain matched filtering processing of the broadband signal. This method can realize the integrated implementation of analog domain windowing and matched filtering, which can significantly reduce the back-end signal processing pressure of the radar system and improve the response speed of the radar system in detecting targets and the resolution of the radar system.

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

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

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

[0112] For example, a mixer can be positioned between the dispersion control module and the optical amplifier. After the first optical signal passes through the dispersion control module, a second optical signal is generated. The second optical signal is first subjected to frequency conversion processing by the mixer, and then optically amplified by the optical amplifier. Alternatively, a mixer can be positioned between a photodetector and a matched filter. After the second optical signal passes through the photodetector, a first electrical signal is generated. The first electrical signal is first subjected to frequency conversion processing by the mixer, and then the converted first electrical signal is subjected to electrical power amplification.

[0113] It should be noted that the mixer can perform frequency conversion processing on optical signals, and the mixer can also perform frequency conversion processing on electrical signals. The signal processing system of microwave photonic 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 matching filter. The number of mixers is not specifically limited in this application.

[0114] In the embodiments of the present application, by performing frequency conversion processing before performing photoelectric conversion processing on the second optical signal, or by performing frequency conversion processing on the first electrical signal after the photoelectric conversion processing, the frequency of the signal can be reduced so that the frequency of the signal can be the same as the frequency of the matched filter, thereby avoiding matching distortion of the signal during the matched filtering process, which affects the implementation of pulse compression and causes radar detection errors.

[0115] Exemplarily, an optical amplifier can be arranged between the dispersion control module and the photodetector to directly amplify the optical power of the second optical signal. The optical amplifier can also be arranged between the mixer and the photodetector to amplify the optical power of the second optical signal after frequency conversion. The electrical amplifier can be arranged between the photodetector and the matched filter to directly amplify the power of the first electrical signal, and the electrical signal amplifier can be arranged between the photodetector and the mixer to amplify the electrical power of the first electrical signal after frequency conversion. By amplifying the optical power before performing photoelectric conversion on the second optical signal after frequency conversion, or by amplifying the electrical power after performing photoelectric conversion on the first electrical signal after frequency conversion, the signal loss generated during the frequency conversion process can be improved, and the main lobe and side lobe power of the signal can be avoided from being too low, resulting in the radar detection system failing to detect the target.

[0116] Exemplarily, the signal processing system of microwave photonic technology is implemented based on discrete devices, or can be integrated with a chip or module and a combination of discrete devices to facilitate the integration of the signal processing system of microwave photonic technology.

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

[0118] The electronic device provided in the embodiment of the present application uses microwave photonic technology to implement analog domain windowing processing of broadband RF signals in the optical domain by regulating the dispersion of a dispersion control module, and uses a matched filter to implement analog domain matched filtering processing of the broadband signal. This method can realize the integrated implementation of analog domain windowing and matched filtering, which can significantly reduce the back-end signal processing pressure of the radar system and improve the response speed of the radar detection equipment in detecting targets and the resolution of the radar detection equipment.

[0119] It should be noted that, in the above embodiments, the description of each embodiment has its own focus. For parts that are not described in detail in a certain embodiment, reference can be made to the relevant descriptions of other embodiments.

[0120] The above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them. Although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present application.

[0121] Although the preferred embodiments of this specification have been described, those skilled in the art may make additional changes and modifications to these embodiments once they have learned the basic creative concepts. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications that fall within the scope of this specification.

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

Claims

1. A signal processing method based on microwave photon technology, characterized in that: include: Acquire an optical carrier; modulating the radio frequency signal to be processed on 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 on the second optical signal to obtain a first electrical signal; Performing matched filtering on the first electrical signal to generate a target electrical signal; The target electrical signal is converted into a digital signal to obtain a digital signal.

2. The signal processing method of microwave photon technology according to claim 1, characterized in that: The adjusting the phase of the first optical signal comprises: The phase of the first optical signal is adjusted by adjusting the dispersion amount of the optical waveguide, wherein the first optical signal is transmitted in the optical waveguide structure.

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

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

5. The signal processing method of microwave photon technology according to claim 4, characterized in that: Before performing the photoelectric conversion process on the second optical signal, performing optical power amplification process on the second optical signal; and / or, After the second optical signal is subjected to photoelectric conversion, the first electrical signal is subjected to electrical power amplification.

6. The signal processing method of microwave photon technology according to claim 1, characterized in that: After the target electrical signal is converted into analog-to-digital, the method further includes: The target electrical signal is transmitted to a display terminal.

7. A signal processing system based on microwave photon technology, characterized in that: include: An optical signal source, the optical signal source being used to output an optical carrier; An electrical radio frequency signal source, the electrical radio frequency signal source being used to output a radio frequency signal; an electro-optical modulator, wherein the optical input interface of the electro-optical modulator is connected to the output interface of the optical signal source, the radio frequency input interface of the electro-optical modulator is connected to the output interface of the radio frequency signal source, and the electro-optical modulator is used to modulate the radio frequency signal on an optical carrier to obtain a first optical signal; a dispersion control module, wherein the output interface of the electro-optical 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, 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 a target electrical signal; An analog-to-digital conversion module, wherein the output interface of the matched filter is connected to the input interface of the analog-to-digital conversion module, and the analog-to-digital conversion module is used to convert the target electrical signal into an analog signal.

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

9. The signal processing system based on microwave photonic technology according to claim 7, further comprising: a signal amplifier, the signal amplifier comprising an optical signal amplifier and an electrical signal amplifier, wherein the optical amplifier is arranged between the dispersion control module and the photodetector; and / or, The electrical signal amplifier is arranged between the photodetector and the filter; a mixer, wherein the mixer is arranged between the dispersion control module and the optical amplifier; and / or, The mixer is arranged between the dispersion control module and the electrical amplifier.

10. An electronic device comprising: A signal processing system based on microwave photonic technology as claimed in any one of claims 7 to 9.

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