Multi-style radar composite interference signal generation method and device based on microwave photons

Abstract

The invention discloses a microwave photon-based multi-style radar composite interference signal generation method and device, and the method comprises the steps: inputting an optical carrier output by a laser light source into a dual-polarization quadrature phase shift keying modulator, and outputting a cross-polarization multiplexing signal according to the dual-polarization quadrature phase shift keying modulator; the cross-polarization multiplexing signals are combined into linearly polarized light through cooperation of a polarization controller and a polarizer; according to the linearly polarized light, performing intensity modulation through an intensity modulator to obtain an intermittent sampling signal; and generating a radar composite interference signal according to the intermittent sampling signal. The device does not need a filter, is compact in structure, is good in real-time performance, is flexible in parameter tuning, can achieve the generation of various radar composite interference signals through changing the interference seed signal pattern under the condition that the hardware structure is not changed, and is suitable for a modern electronic countermeasure system.

Description

Technical Field

[0001] This invention belongs to the field of radar jamming technology, and particularly relates to a method and apparatus for generating multi-mode radar composite jamming signals based on microwave photons. Background Technology

[0002] With the rapid development of modern radar technology, electronic warfare has become a key area determining the outcome of future wars. As a core piece of equipment for battlefield information perception, radar's jamming and countermeasure capabilities have always been a perennial theme in electronic warfare. With the emergence of ultra-wideband, high-resolution radar systems, traditional electronic jamming technologies face challenges such as limited bandwidth and insufficient real-time performance. Microwave photonics technology, with its inherent advantages of large bandwidth, low transmission loss, and resistance to electromagnetic interference, has been widely applied in the field of radar countermeasures. Microwave photonics-based jamming systems can directly modulate intercepted radar signals in the optical domain, bypassing the complex analog-to-digital and digital-to-analog conversion processes. This overcomes the bandwidth limitations of traditional electronic jammers, significantly improving the real-time processing capabilities of radar jamming systems and the performance of electronic countermeasures systems.

[0003] However, existing microwave photonics-based radar jamming signal generation devices still suffer from the following technical shortcomings: Existing solutions typically employ multiple separate modulators cascaded or paralleled structures, resulting in complex system structures and large volumes, which are not conducive to actual battlefield deployment; some solutions require the use of filters for signal processing, introducing additional insertion loss and inflexible tuning, which limits the real-time performance and parameter adjustability of signal generation; in addition, existing technologies mostly adopt a single jamming pattern generation method, making it difficult to flexibly switch between multiple composite jamming signals without changing the hardware structure, thus failing to adapt to the complex and ever-changing electronic warfare environment; at the same time, the power fading problem caused by fiber dispersion also restricts the quality of jamming signals and link linearity. Summary of the Invention

[0004] To address the aforementioned technical problems, this invention provides a method and apparatus for generating multi-mode radar composite jamming signals based on microwave photons.

[0005] One method for generating multi-pattern radar composite jamming signals based on microwave photons includes:

[0006] The optical carrier output from the laser source is input to a dual-polarization quadrature phase shift keying modulator, and the dual-polarization quadrature phase shift keying modulator outputs an orthogonal polarization multiplexed signal.

[0007] The orthogonal polarization multiplexed signal is combined into linearly polarized light by a polarization controller and a polarizer.

[0008] Based on the linearly polarized light, an intermittent sampling signal is obtained by intensity modulation through an intensity modulator;

[0009] A radar composite jamming signal is generated based on the intermittently sampled signal.

[0010] Preferably, the process of inputting the optical carrier wave output from the laser source to the dual-polarization quadrature phase-shift keying modulator includes:

[0011] Based on the optical carrier, the linear frequency modulation signal is subjected to suppressed carrier single-sideband modulation by X-DPMZM in the dual polarization orthogonal phase shift keying modulator to obtain the X polarization state signal;

[0012] Based on the optical carrier, the interference seed signal is phase-modulated by the Y-DPMZM in the dual polarization orthogonal phase shift keying modulator to obtain the Y-polarization state signal.

[0013] Preferably, the process of obtaining the X-polarization state signal includes:

[0014] Based on the linear frequency modulation signal, two radio frequency signals with a 90-degree phase difference are generated through a 90-degree bridge.

[0015] Two radio frequency signals with a 90-degree phase difference are input to the upper and lower arm radio frequency ports of the X-DPMZM respectively. Based on the bias states of the upper and lower arm sub-modulators and the main modulator of the X-DPMZM operating at the minimum point, minimum point and orthogonal point respectively, the suppressed carrier single-sideband modulation is realized.

[0016] Preferably, the process of obtaining the Y-polarization state signal includes:

[0017] The interference seed signal is split into two paths and input to the upper and lower arm RF ports of the Y-DPMZM respectively. Based on the bias states of the upper and lower arm sub-modulators and the main modulator of the Y-DPMZM operating at the maximum point, minimum point and orthogonal point respectively, phase modulation is performed and the phase modulation signal is output.

[0018] The polarization state of the phase modulation signal is rotated by 90 degrees using a 90-degree polarization rotator to obtain the Y-polarized signal.

[0019] Preferably, the process of combining the orthogonally polarized multiplexed signals into linearly polarized light using a polarization controller and a polarizer includes:

[0020] Based on the X-polarization state signal and the Y-polarization state signal, an orthogonal polarization multiplexed signal is formed by a polarization beam combiner;

[0021] Based on the orthogonal polarization multiplexed signal, the polarization controller is used to make one of the polarization state principal axes form a 45-degree angle with the polarizer principal axis.

[0022] Based on the 45-degree polarization state configuration, the polarizer combines the orthogonal polarization multiplexed signals into linearly polarized light.

[0023] Preferably, the process of obtaining an intermittent sampling signal by intensity modulation using an intensity modulator based on the linearly polarized light includes:

[0024] The linearly polarized light input intensity modulator is used as the optical carrier. The optical carrier is intensity modulated according to the periodic rectangular pulse signal loaded at the radio frequency port of the intensity modulator. The intermittent sampling signal is obtained according to the high and low level configuration of the periodic rectangular pulse signal.

[0025] Preferably, the process of generating a radar composite interference signal based on the intermittently sampled signal includes:

[0026] Based on the intermittent sampling signal, the power is amplified by an erbium-doped fiber amplifier to obtain the amplified intermittent sampling signal;

[0027] The intermittently sampled signal after power amplification is transmitted through a single-mode optical fiber to obtain the transmitted intermittently sampled signal.

[0028] Based on the intermittently sampled signal after transmission, a photoelectric conversion is performed by a photodetector to obtain the photoelectric converted signal;

[0029] The radar composite jamming signal is generated based on the signal after photoelectric conversion.

[0030] The present invention also provides a multi-pattern radar composite jamming signal generation device based on microwave photons, comprising:

[0031] Laser source, dual polarization quadrature phase shift keying modulator, arbitrary waveform generator, 90-degree bridge, arbitrary signal generator, polarization controller, polarizer, arbitrary function generator, intensity modulator, erbium-doped fiber amplifier, single-mode fiber, photodetector, signal generation module;

[0032] The dual-polarization orthogonal phase-shift keying modulator is used to receive the optical carrier output from the laser source and modulate the optical carrier to obtain an orthogonal polarization multiplexed signal.

[0033] The polarization controller and polarizer are used to combine the orthogonal polarization multiplexed signal into linearly polarized light according to the orthogonal polarization multiplexed signal;

[0034] The intensity modulator is used to perform intensity modulation based on the linearly polarized light to obtain an intermittent sampling signal;

[0035] The signal generation module is used to generate a radar composite interference signal based on the intermittently sampled signal.

[0036] Preferably, the dual-polarization quadrature phase shift keying modulator includes X-DPMZM and Y-DPMZM;

[0037] The X-DPMZM is used to perform suppressed carrier single-sideband modulation on the linear frequency modulation signal according to the optical carrier to obtain the X polarization state signal.

[0038] The Y-DPMZM is used to perform phase modulation on the interference seed signal according to the optical carrier to obtain the Y-polarization state signal.

[0039] Preferably, the signal generation module includes an erbium-doped fiber amplifier, a single-mode fiber, and a photodetector;

[0040] The erbium-doped fiber amplifier is used to amplify the power based on the intermittently sampled signal to obtain a power amplified signal.

[0041] The single-mode optical fiber is used to transmit the power amplified signal to obtain the transmitted signal.

[0042] The photodetector is used to perform photoelectric conversion based on the transmitted signal to obtain the radar composite interference signal.

[0043] Compared with the prior art, the present invention has the following advantages and technical effects:

[0044] This invention employs a cascaded structure of a dual-polarization quadrature phase-shift keying modulator and an intensity modulator, enabling the generation of various radar composite jamming signals without the need for filters. The system boasts a simple and compact structure, excellent real-time performance, flexible parameter tuning, and high coherence of the generated signals. By suppressing carrier single-sideband modulation, it effectively avoids power fading caused by fiber dispersion, resulting in high link linearity. The equivalent phase modulation method avoids the use of a separate modulator, making the overall structure more compact. By changing only the jamming seed signal pattern without altering the overall modulator structure, it is possible to flexibly generate various radar composite jamming signals such as cosine phase modulation and frequency shifting, significantly improving the system's adaptability and combat effectiveness. Attached Figure Description

[0045] The accompanying drawings, which form part of this application, are used to provide a further understanding of this application. The illustrative embodiments and descriptions of this application are used to explain this application and do not constitute an undue limitation of this application. In the drawings:

[0046] Figure 1 This is a schematic diagram of the device structure according to an embodiment of the present invention;

[0047] Figure 2In this embodiment of the invention, the interference seed signal uses a 4MHz cosine signal, and the intermittent sampling uses a periodic rectangular pulse signal with a 50% duty cycle and a frequency of 1MHz to generate a cosine phase modulation + intermittent sampling composite interference signal. Among them, (a) is the electrical spectrum of the cosine phase modulation + intermittent sampling composite interference signal; (b) is the waveform of the cosine phase modulation + intermittent sampling composite interference signal; (c) is the time-frequency diagram of the cosine phase modulation + intermittent sampling composite interference signal; and (d) is the time domain diagram of the cosine phase modulation + intermittent sampling composite interference signal after pulse compression.

[0048] Figure 3 The interference seed signal used in this embodiment of the invention is a 4MHz sawtooth wave signal. Intermittent sampling uses a periodic rectangular pulse signal with a duty cycle of 50% and a frequency of 1MHz to generate a cosine phase-modulated + intermittent sampling composite interference signal. (a) is the electrical spectrum of the frequency-shift + intermittent sampling composite interference signal; (b) is the waveform of the frequency-shift + intermittent sampling composite interference signal; (c) is the time-frequency diagram of the frequency-shift + intermittent sampling composite interference signal; (d) is the time-domain diagram of the frequency-shift + intermittent sampling composite interference signal after pulse compression. Detailed Implementation

[0049] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other. This application will now be described in detail with reference to the accompanying drawings and embodiments.

[0050] It should be noted that the steps shown in the flowchart in the accompanying drawings can be executed in a computer system such as a set of computer-executable instructions, and although a logical order is shown in the flowchart, in some cases the steps shown or described may be executed in a different order than that shown here.

[0051] Example 1

[0052] This embodiment provides a method for generating multi-mode radar composite jamming signals based on microwave photons, including:

[0053] The optical carrier output from the laser source is input to the dual-polarization quadrature phase shift keying modulator, and the quadrature polarization multiplexed signal is output from the dual-polarization quadrature phase shift keying modulator.

[0054] The orthogonally polarized multiplexed signals are combined into linearly polarized light by using a polarization controller and a polarizer.

[0055] Based on linearly polarized light, an intermittent sampling signal is obtained by intensity modulation using an intensity modulator;

[0056] A radar composite jamming signal is generated based on the intermittently sampled signal.

[0057] Furthermore, the process of inputting the optical carrier wave output from the laser source into the dual-polarization quadrature phase-shift keying modulator includes:

[0058] Based on the optical carrier, the linear frequency modulation signal is subjected to suppressed carrier single-sideband modulation by X-DPMZM in the dual polarization quadrature phase shift keying modulator to obtain the X polarization state signal;

[0059] Based on the optical carrier, the interference seed signal is phase-modulated by the Y-DPMZM in the dual polarization quadrature phase shift keying modulator to obtain the Y-polarized state signal.

[0060] Furthermore, the process of obtaining the X-polarization state signal includes:

[0061] Based on the linear frequency modulation signal, two radio frequency signals with a 90-degree phase difference are generated through a 90-degree bridge.

[0062] Two RF signals with a 90-degree phase difference are input to the upper and lower arm RF ports of the X-DPMZM respectively. Based on the bias states of the upper and lower arm sub-modulators and the main modulator of the X-DPMZM operating at the minimum point, minimum point and quadrature point respectively, the carrier single-sideband modulation is suppressed.

[0063] Furthermore, the process of obtaining the Y-polarization state signal includes:

[0064] The interference seed signal is split into two paths and input to the upper and lower arm RF ports of the Y-DPMZM respectively. Based on the bias states of the upper and lower arm sub-modulators and the main modulator of the Y-DPMZM working at the maximum point, minimum point and quadrature point respectively, phase modulation is performed and the phase modulation signal is output.

[0065] The polarization state of the phase-modulated signal is rotated by 90 degrees using a 90-degree polarization rotator to obtain a Y-polarized signal.

[0066] Furthermore, the process of combining orthogonally polarized multiplexed signals into linearly polarized light using a polarization controller and a polarizer includes:

[0067] Based on the X-polarization state signal and the Y-polarization state signal, an orthogonal polarization multiplexed signal is formed by a polarization beam combiner;

[0068] Based on the orthogonal polarization multiplexing signal, the polarization controller is rotated to make one of the polarization state principal axes form a 45-degree angle with the polarizer principal axis.

[0069] Based on the 45-degree polarization configuration, the orthogonal polarization multiplexed signals are combined into linearly polarized light by a polarizer.

[0070] Furthermore, the process of obtaining an intermittent sampling signal by intensity modulation using an intensity modulator based on linearly polarized light includes:

[0071] Linearly polarized light is input to an intensity modulator as an optical carrier. The optical carrier is intensity modulated according to a periodic rectangular pulse signal loaded at the RF port of the intensity modulator. An intermittent sampling signal is obtained by configuring the high and low levels of the periodic rectangular pulse signal.

[0072] Furthermore, the process of generating radar composite interference signals based on intermittently sampled signals includes:

[0073] Based on the intermittent sampling signal, the power is amplified by an erbium-doped fiber amplifier to obtain the amplified intermittent sampling signal;

[0074] The intermittently sampled signal after power amplification is transmitted through a single-mode optical fiber to obtain the transmitted intermittently sampled signal.

[0075] Based on the intermittently sampled signal after transmission, a photoelectric conversion is performed by a photodetector to obtain the photoelectric converted signal;

[0076] A radar composite jamming signal is generated based on the signal after photoelectric conversion.

[0077] This method uses a cascaded dual-polarization quadrature phase shift keying modulator (DP-QPSK) and an IM modulator, eliminating the need for filters. It features a simple structure, good real-time performance, flexible parameter tuning, and high coherence of the generated signal. The DP-QPSK upper path employs suppressed-carrier single-sideband modulation, ensuring the signal is unaffected by power fading caused by fiber dispersion and exhibiting high link linearity. The DP-QPSK lower path uses equivalent phase modulation, avoiding the use of separate modulators and resulting in a compact overall structure. This invention can generate various radar composite jamming signals without altering the overall modulator structure, only changing the pattern of the jamming seed signal.

[0078] As a preferred implementation method, the method of this embodiment specifically includes the following steps:

[0079] Construct a photon-based multi-pattern radar jamming signal generation device;

[0080] The optical carrier emitted by the laser source is input into the X-DPMZM modulator and Y-DPMZM modulator in the DP-QPSK modulator respectively via an optical fiber beam splitter;

[0081] The linear frequency modulation signal generated by the arbitrary waveform generator (AWG) is input into the X-DPMZM modulator and split into two paths. One path is input into Xa, and the other path is input into Xb after passing through a 90-degree bridge. The X-DPMZM modulator performs suppressed carrier single-sideband modulation.

[0082] The interference seed signal ASG is input into the Y-DPMZM modulator, split into two paths, and input into Ya and Yb respectively, where phase modulation is performed in the Y-DPMZM modulator;

[0083] Furthermore, the X-DPMZM modulated linear frequency-modulated signal is in the X-polarization state. The Y-DPMZM signal is then biased to the Y-polarization state by a 90-degree polarization rotator. The X-DPMZM and Y-DPMZM signals are then combined into an orthogonal polarization multiplexed signal by a polarization combiner (PBC). By rotating the polarization controller, one of the polarization states of the multiplexed signal is aligned with the principal axis of the polarizer at a 45-degree angle, and the orthogonal polarization multiplexed optical signal is combined into linearly polarized light.

[0084] Furthermore, the linearly polarized light is used as an optical carrier input to the intensity modulator IM for intensity modulation. An arbitrary function generator AFG is loaded onto the radio frequency port of the intensity modulator to perform intensity modulation on the input optical carrier.

[0085] Furthermore, the arbitrary function generator (AFG) can generate periodic rectangular pulse signals. Based on the time-frequency characteristics of periodic rectangular pulses, the input optical carrier signal changes with the period of the rectangular pulse. By appropriately setting the high and low levels of the rectangular pulse (high level = 1, low level = 0), it can be equivalent to intermittent sampling. The sampled signal from the rectangular pulse is amplified by an erbium-doped fiber amplifier, transmitted through a single-mode fiber, and then sent to a photodetector for photoelectric conversion, thereby generating a radar composite interference signal.

[0086] The Arbitrary Signal Generator (ASG) can generate different types of interference seed signals, such as cosine signals and sawtooth wave signals.

[0087] Furthermore, both the dual polarization quadrature phase shift keying modulator DP-QPSK and the intensity modulator IM are connected to a DC bias source.

[0088] Furthermore, it also includes an erbium-doped fiber amplifier device, which is transmitted via single-mode fiber and then connected to a photodetector to enhance the power of radar composite interference signals.

[0089] Furthermore, it also includes a signal analyzer, which is connected to a photodetector to observe the characteristics of radar interference signals.

[0090] Furthermore, the laser source generates a carrier wave with an operating wavelength of 1553.5 nm.

[0091] Furthermore, the arbitrary function generator AFG is a periodic rectangular pulse signal.

[0092] Furthermore, the arbitrary waveform generator (AWG) generates a linear frequency modulated signal.

[0093] In the above embodiments, the specific implementation steps of the method in this embodiment are as follows:

[0094] Step 1: The laser source generates a continuous light wave with a working wavelength of 1553.50nm and a power of 15dBm. This continuous light wave is used as an optical carrier input to the dual polarization quadrature phase shift keying modulator DP-QPSK.

[0095] Step 2: Use a vector signal source to output an LFM radar signal with a center frequency of 8GHz, a bandwidth of 1GHz, and a duration of 10μs. Split the LFM radar signal into two paths using a power divider, and input them to the RF ports of the upper and lower arms of the X-DPMZM, respectively. The phase difference between the upper and lower arm signals is 90 degrees. The bias voltages of the three MZM modulators of the X-DPMZM are set at the minimum point, minimum point, and quadrature point, respectively. Use an arbitrary signal generator (ASG) to output a cosine phase-modulated signal with a frequency of 4MHz, and input it to the RF ports of the upper and lower arms of the Y-DPMZM, respectively. The bias voltages of the three MZM modulators of the Y-DPMZM are set at the maximum point, minimum point, and quadrature point, respectively.

[0096] Step 3: The output signal of the DP-QPSK modulator is combined into linearly polarized light by passing it through a rotating polarization controller and a polarizer.

[0097] Step 4: Linearly polarized light is used as an optical carrier and input to an intensity modulator for intensity modulation. A periodic rectangular pulse signal is loaded onto the radio frequency port of the intensity modulator to achieve intermittent sampling.

[0098] Step 5: Transmit the output signal of the IM modulator through a single-mode fiber and input it into an erbium-doped fiber amplifier for power amplification.

[0099] Step 6: Control the cosine phase modulation + intermittent sampling composite interference signal output by the photodetector after frequency capture.

[0100] Step 7: In order to explore different interference seed signals and generate composite interference signals with different interference patterns, the output of the arbitrary signal generator ASG in Step 2 is a sawtooth wave signal with a frequency of 4MHz. Repeat Steps 2 to 5.

[0101] Step 8: Control the frequency shift + intermittent sampling composite interference signal output by the photodetector after frequency capture.

[0102] like Figure 2 The diagram shows the interference seed signal using a 4MHz cosine signal, and the intermittent sampling using a 1MHz periodic rectangular pulse signal with a 50% duty cycle to generate a cosine phase-modulated + intermittent sampling composite interference signal. The diagram also shows the effect after pulse compression processing of the interference signal. As can be seen from the pulse compression processing diagram, the primary false target appears 40ns from zero, which matches the set cosine signal frequency of 4MHz. The primary false target is spaced 10ns from its nearest secondary false target, which matches the set intermittent sampling signal frequency of 1MHz.

[0103] like Figure 3 The diagram shows the interference seed signal using a 4MHz sawtooth wave signal, and the intermittent sampling using a 1MHz periodic rectangular pulse signal with a 50% duty cycle to generate a cosine phase-modulated + intermittent sampling composite interference signal. The diagram also shows the effect after pulse compression processing of the interference signal. As can be seen from the pulse compression processing diagram, a primary false target appears 0.04µs from the zero point, which matches the 4MHz frequency of the sawtooth wave signal. The primary false target is spaced 0.01µs from its nearest secondary false target, which matches the 1MHz frequency of the intermittent sampling signal.

[0104] In summary, this embodiment can generate various styles of composite jamming signals using a DP-QPSK and an IM cascade. It has a simple structure, good real-time performance, flexible parameter tuning, and the generated jamming signals have high frequency bands, large instantaneous bandwidth, and wide operating range, which is suitable for the current radar electronic warfare needs and development trends.

[0105] Example 2

[0106] Based on the same inventive concept, this embodiment also provides a multi-mode radar composite jamming signal generation device based on microwave photons, including:

[0107] Laser source, dual polarization quadrature phase shift keying modulator, arbitrary waveform generator, 90-degree bridge, arbitrary signal generator, polarization controller, polarizer, arbitrary function generator, intensity modulator, erbium-doped fiber amplifier, single-mode fiber, photodetector, signal generation module;

[0108] Among them, the dual-polarization orthogonal phase-shift keying modulator is used to receive the optical carrier output from the laser source and modulate the optical carrier to obtain an orthogonal polarization multiplexed signal;

[0109] The polarization controller and polarizer are used to combine orthogonal polarization multiplexed signals into linearly polarized light based on the orthogonal polarization multiplexed signals.

[0110] An intensity modulator is used to modulate the intensity of linearly polarized light to obtain an intermittently sampled signal.

[0111] The signal generation module is used to generate radar composite interference signals based on intermittently sampled signals.

[0112] The device provided in this embodiment does not require a filter, has a simple structure, and offers the advantage of high-frequency tunability. It features a simple structure, good real-time performance, flexible parameter tuning, and good coherence of the generated signal. Using suppressed carrier single-sideband modulation, the signal is unaffected by power fading caused by fiber dispersion, resulting in high link linearity. The use of equivalent phase modulation avoids the need for a separate modulator, making the overall structure compact.

[0113] This embodiment can generate various styles of radar composite jamming signals without changing the overall structure of the modulator, only by changing the style of the jamming seed signal. It is suitable for electronic countermeasures systems and has good application prospects.

[0114] Furthermore, the dual-polarization quadrature phase shift keying modulator includes X-DPMZM and Y-DPMZM;

[0115] X-DPMZM is used to suppress carrier single-sideband modulation of linear frequency modulated signals based on optical carriers to obtain X-polarized state signals.

[0116] Y-DPMZM is used to phase modulate the interference seed signal according to the optical carrier to obtain the Y-polarized state signal.

[0117] The dual-polarization quadrature phase shift keying modulator obtains an orthogonal polarization multiplexed signal based on the X-polarization state signal and the Y-polarization state signal.

[0118] Furthermore, the X-DPMZM includes upper and lower arm sub-modulators and a main modulator;

[0119] The upper and lower arm RF ports of the X-DPMZM are used to receive two RF signals with a 90-degree phase difference, generated by a 90-degree bridge based on a linear frequency modulation signal.

[0120] The upper and lower arm sub-modulators and the main modulator of the X-DPMZM are used to operate in the bias states of minimum point, minimum point and orthogonal point respectively, so as to achieve single-sideband modulation of the suppressed carrier of the linear frequency modulated signal and obtain the X polarization state signal.

[0121] Furthermore, the Y-DPMZM includes upper and lower arm sub-modulators, a main modulator, and a 90-degree polarization rotator;

[0122] The upper and lower arm RF ports of the Y-DPMZM are used to receive the two signals split from the interference seed signal.

[0123] The upper and lower arm sub-modulators and the main modulator of the Y-DPMZM are used to operate in bias states at the maximum point, minimum point and orthogonal point respectively to achieve phase modulation of the interference seed signal and obtain the phase modulated signal.

[0124] A 90-degree polarization rotator is used to rotate the polarization state of a phase modulation signal by 90 degrees to obtain a Y-polarized signal.

[0125] Furthermore, it also includes a polarization beam combiner for forming an orthogonal polarization multiplexed signal based on the X-polarization state signal and the Y-polarization state signal;

[0126] A polarization controller is used to adjust one of the polarization state principal axes to form a 45-degree angle with the polarizer principal axis by rotation based on the orthogonal polarization multiplexing signal.

[0127] A polarizer is used to combine orthogonally polarized multiplexed signals into linearly polarized light according to a 45-degree polarization state configuration.

[0128] Furthermore, the intensity modulator includes an RF input port for receiving a periodic rectangular pulse signal output from an arbitrary function generator;

[0129] An intensity modulator is used to modulate the intensity of linearly polarized light, which serves as an optical carrier, based on a periodic rectangular pulse signal. By configuring the high and low levels of the periodic rectangular pulse signal, an intermittent sampling signal is obtained.

[0130] Furthermore, it also includes an arbitrary signal generator for generating cosine or sawtooth wave signals as interference seed signals;

[0131] Y-DPMZM generates a cosine phase-modulated signal based on a cosine signal, or a frequency-shifted signal based on a sawtooth wave signal.

[0132] Furthermore, it also includes an arbitrary function generator for generating periodic rectangular pulse signals, which adjusts the number of false targets generated by the intermittent sampling signal by changing the duty cycle and period parameter of the periodic rectangular pulse signal.

[0133] An arbitrary signal generator is used to adjust the number and location of false targets generated by radar composite jamming signals by changing the frequency, amplitude, or modulation index of the jamming seed signal.

[0134] The interference seed signal includes a cosine signal or a sawtooth wave signal; based on the cosine signal, a cosine phase-modulated composite interference signal is generated; based on the sawtooth wave signal, a frequency-shifted composite interference signal is generated.

[0135] In this embodiment, the number of false targets generated by the intermittent sampling signal is adjusted by changing the duty cycle and period parameter of the periodic rectangular pulse signal.

[0136] This embodiment adjusts the number and location of false targets formed by the radar composite jamming signal based on changes in the frequency, amplitude, or modulation index of the jamming seed signal.

[0137] Furthermore, the signal generation module includes an erbium-doped fiber amplifier, a single-mode fiber, and a photodetector;

[0138] Erbium-doped fiber amplifiers are used to amplify power based on intermittently sampled signals to obtain amplified power signals.

[0139] Single-mode fiber is used to transmit power-amplified signals to obtain the transmitted signal.

[0140] A photodetector is used to perform photoelectric conversion on the transmitted signal to obtain radar composite interference signals.

[0141] Furthermore, in this embodiment, the optical carrier output from the laser source is directly input into a dual-polarization orthogonal phase-shift keying modulator (DP-QPSK). The DP-QPSK modulator includes two parallel Mach-Zehnder modulators, X-DPMZM and Y-DPMZM. The linear frequency modulated radar signal is loaded into the X-DPMZM for suppressed carrier single-sideband modulation; the interference seed signal ASG is loaded into the Y-DPMZM for phase modulation. The Y-DPMZM signal then passes through a 90-degree polarization rotator to rotate its polarization state by 90 degrees. The X-DPMZM modulated LFM signal and the Y-DPMZM modulated signal are orthogonal to each other. The upper and lower signals are then combined by a polarization combiner (PBC) to form an orthogonal polarization multiplexed signal. By rotating the polarization controller, one of the polarization states of the multiplexed signal is aligned at a 45-degree angle with the principal axis of the polarizer, and the orthogonal polarization multiplexed optical signal is combined into linearly polarized light.

[0142] Next, this linearly polarized light is used as an optical carrier input to the intensity modulator IM for intensity modulation. The RF port of the intensity modulator IM is loaded with a periodic rectangular pulse signal AFG. Based on the time-frequency characteristics of periodic rectangular pulses, the input optical carrier signal changes with the period of the rectangular pulse. By appropriately setting the high and low levels of the rectangular pulse (high level = 1, low level = 0), it can be equivalent to intermittent sampling. The signal sampled by the rectangular pulse is amplified by the EDFA, transmitted through optical fiber, and then sent to the photodetector PD for photoelectric conversion, thereby generating a radar composite interference signal.

[0143] More specifically, the linear frequency modulated signal generated by the arbitrary waveform generator (AWG) is split into two paths: one path is connected to the Xa RF port of the X-DPMZM, and the other path is connected to the Xb RF port of the X-DPMZM after passing through a 90-degree bridge. The upper and lower sub-modulators and the main modulator of the X-DPMZM operate at the minimum point, minimum point, and quadrature point, respectively, to achieve suppression of carrier unilateral modulation.

[0144] More specifically, the arbitrary signal generator (ASG) is split into two paths, which are connected to the RF ports of Ya and Yb of the Y-DPMZM respectively; the up modulator, down modulator and main modulator of the Y-DPMZM operate at the maximum point, minimum point and quadrature point respectively to achieve phase modulation.

[0145] More specifically, when the arbitrary signal generator ASG outputs a cosine signal and the AFG outputs a periodic rectangular pulse signal, a cosine phase-modulated + intermittent sampling composite interference signal can be generated. When the arbitrary signal generator ASG outputs a sawtooth wave signal and the AFG outputs a periodic rectangular pulse signal, a frequency-shifted + intermittent sampling composite interference signal can be generated.

[0146] More specifically, by changing the duty cycle and period of the periodic rectangular pulse signal output by the AFG, intermittent sampling interference signals with different numbers of false targets can be generated.

[0147] More specifically, when the frequency, amplitude, modulation index, etc. of the interference seed signal output by the arbitrary signal generator ASG are changed, the number and location of the false targets formed by the generated interference signal will change accordingly.

[0148] More specifically, multi-dimensional parameter joint optimization can be achieved by simultaneously changing the duty cycle and period of the periodic rectangular pulse signal output by the AFG and the frequency, amplitude, and modulation index of the interference seed signal output by the arbitrary signal generator ASG.

[0149] The multi-pattern radar composite jamming signal generation device based on microwave photons provided in this embodiment has all the advantages of the multi-pattern radar composite jamming signal generation method based on microwave photons provided in Embodiment 1.

[0150] As a preferred implementation method, such as Figure 1 As shown, the device in this embodiment includes a laser source, a dual polarization quadrature phase shift keying modulator (DP-QPSK), an arbitrary waveform generator (AWG), a 90-degree bridge, an arbitrary signal generator (ASG), a polarization controller, a polarizer, an arbitrary function generator (AFG), an intensity modulator (IM), an erbium-doped fiber amplifier, a single-mode fiber, and a photodetector.

[0151] The DP-QPSK dual-polarization quadrature phase-shift keying modulator integrates two dual-parallel Mach-Zehnder modulators, located in its upper and lower arms respectively. The lower arm also integrates a 90° polarization rotator. Each dual-parallel Mach-Zehnder modulator integrates three MZMs: two sub-MZMs in the upper and lower arms and one main MZM. Finally, the polarization combiner (PBC) multiplexes the polarization of the light waves from both arms before outputting the final signal. The optical carrier output from the laser source is split into two paths and enters the DP-QPSK. The linear frequency modulated signal generated by the arbitrary waveform generator (AWG) is input to the X-DPMZM modulator, which is split into two paths: one path is input to Xa, and the other path is input to Xb after passing through a 90-degree bridge. In the X-DPMZM modulator, the suppressed carrier single-sideband modulation is performed. The bias voltages of the two sub-MZMs in the upper and lower arms of the X-DPMZM are set at the minimum point, and the bias voltage of the main MZM is set at the quadrature point. The interference seed signal (ASG) is input to the Y-DPMZM modulator, which is split into two paths and input to Ya and Yb respectively. In the Y-DPMZM modulator, phase modulation is performed. The bias voltages of the two sub-MZMs in the upper and lower arms of the Y-DPMZM are set at the maximum and minimum points respectively, and the bias voltage of the main MZM is set at the quadrature point. The optical signal output from the DP-QPSK is processed by a rotating polarization controller, which aligns one of the polarization states of the polarization multiplexed signal at a 45-degree angle to the principal axis of the polarizer. The orthogonally polarized multiplexed optical signal is then bundled into linearly polarized light. This linearly polarized light serves as the optical carrier and is input to an intensity modulator (IM) for intensity modulation. An arbitrary function generator (AFG) is loaded onto the RF port of the IM. The AFG generates periodic rectangular pulse signals, enabling intermittent sampling. The signal, after periodic rectangular pulse sampling, is amplified by an erbium-doped fiber amplifier, transmitted through a single-mode fiber, and then sent to a photodetector for photoelectric conversion, ultimately generating a radar composite interference signal.

[0152] Example 3

[0153] This embodiment also discloses a computer device, including a memory, a processor, and a computer program stored in the memory, wherein the processor executes the computer program to implement the steps of the method described in Embodiment 1.

[0154] Example 4

[0155] This embodiment also discloses a computer-readable storage medium storing a computer program thereon, which, when executed by a processor, implements the steps of the method described in Embodiment 1.

[0156] Example 5

[0157] This embodiment also discloses a computer program product, including a computer program that, when executed by a processor, implements the steps of the method described in Embodiment 1.

[0158] The above are merely preferred embodiments of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A method for generating multi-pattern radar composite jamming signals based on microwave photons, characterized in that, include: The optical carrier output from the laser source is input to a dual-polarization quadrature phase shift keying modulator, and the dual-polarization quadrature phase shift keying modulator outputs an orthogonal polarization multiplexed signal. The orthogonal polarization multiplexed signal is combined into linearly polarized light by a polarization controller and a polarizer. Based on the linearly polarized light, an intermittent sampling signal is obtained by intensity modulation through an intensity modulator; A radar composite jamming signal is generated based on the intermittently sampled signal.

2. The method according to claim 1, characterized in that, The process of inputting the optical carrier wave output from the laser source into a dual-polarization quadrature phase-shift keying modulator includes: Based on the optical carrier, the linear frequency modulation signal is subjected to suppressed carrier single-sideband modulation by X-DPMZM in the dual polarization orthogonal phase shift keying modulator to obtain the X polarization state signal; Based on the optical carrier, the interference seed signal is phase-modulated by the Y-DPMZM in the dual polarization orthogonal phase shift keying modulator to obtain the Y-polarization state signal.

3. The method according to claim 2, characterized in that, The process of obtaining the X-polarization state signal includes: Based on the linear frequency modulation signal, two radio frequency signals with a 90-degree phase difference are generated through a 90-degree bridge. Two radio frequency signals with a 90-degree phase difference are input to the upper and lower arm radio frequency ports of the X-DPMZM respectively. Based on the bias states of the upper and lower arm sub-modulators and the main modulator of the X-DPMZM operating at the minimum point, minimum point and orthogonal point respectively, the suppressed carrier single-sideband modulation is realized.

4. The method according to claim 2, characterized in that, The process of obtaining the Y-polarization state signal includes: The interference seed signal is split into two paths and input to the upper and lower arm RF ports of the Y-DPMZM respectively. According to the bias states of the upper and lower arm sub-modulators and the main modulator of the Y-DPMZM working at the maximum point, minimum point and orthogonal point respectively, phase modulation is performed and the phase modulation signal is output. The polarization state of the phase modulation signal is rotated by 90 degrees using a 90-degree polarization rotator to obtain the Y-polarized signal.

5. The method according to claim 1, characterized in that, The process of combining the orthogonally polarized multiplexed signals into linearly polarized light using a polarization controller and a polarizer includes: Based on the X-polarization state signal and the Y-polarization state signal, an orthogonal polarization multiplexed signal is formed by a polarization beam combiner; Based on the orthogonal polarization multiplexed signal, the polarization controller is used to make one of the polarization state principal axes form a 45-degree angle with the polarizer principal axis. Based on the 45-degree polarization state configuration, the polarizer combines the orthogonal polarization multiplexed signals into linearly polarized light.

6. The method according to claim 1, characterized in that, The process of obtaining an intermittent sampling signal by intensity modulation using an intensity modulator based on the linearly polarized light includes: The linearly polarized light input intensity modulator is used as the optical carrier. The optical carrier is intensity modulated according to the periodic rectangular pulse signal loaded at the radio frequency port of the intensity modulator. The intermittent sampling signal is obtained according to the high and low level configuration of the periodic rectangular pulse signal.

7. The method according to claim 1, characterized in that, The process of generating a radar composite jamming signal based on the intermittently sampled signal includes: Based on the intermittent sampling signal, the power is amplified by an erbium-doped fiber amplifier to obtain the amplified intermittent sampling signal; The intermittently sampled signal after power amplification is transmitted through a single-mode optical fiber to obtain the transmitted intermittently sampled signal. Based on the intermittently sampled signal after transmission, a photoelectric conversion is performed by a photodetector to obtain the photoelectric converted signal; The radar composite jamming signal is generated based on the signal after photoelectric conversion.

8. A multi-mode radar composite jamming signal generation device based on microwave photons, characterized in that, include: Laser source, dual polarization quadrature phase shift keying modulator, arbitrary waveform generator, 90-degree bridge, arbitrary signal generator, polarization controller, polarizer, arbitrary function generator, intensity modulator, erbium-doped fiber amplifier, single-mode fiber, photodetector, signal generation module; The dual-polarization orthogonal phase-shift keying modulator is used to receive the optical carrier output from the laser source and modulate the optical carrier to obtain an orthogonal polarization multiplexed signal. The polarization controller and polarizer are used to combine the orthogonal polarization multiplexed signal into linearly polarized light according to the orthogonal polarization multiplexed signal; The intensity modulator is used to perform intensity modulation based on the linearly polarized light to obtain an intermittent sampling signal; The signal generation module is used to generate a radar composite interference signal based on the intermittently sampled signal.

9. The apparatus according to claim 8, characterized in that, The dual polarization orthogonal phase shift keying modulator includes X-DPMZM and Y-DPMZM; The X-DPMZM is used to perform suppressed carrier single-sideband modulation on the linear frequency modulation signal according to the optical carrier to obtain the X polarization state signal. The Y-DPMZM is used to perform phase modulation on the interference seed signal according to the optical carrier to obtain the Y-polarization state signal.

10. The apparatus according to claim 8, characterized in that, The signal generation module includes an erbium-doped fiber amplifier, a single-mode fiber, and a photodetector; The erbium-doped fiber amplifier is used to amplify the power based on the intermittently sampled signal to obtain a power amplified signal. The single-mode optical fiber is used to transmit the power amplified signal to obtain the transmitted signal. The photodetector is used to perform photoelectric conversion based on the transmitted signal to obtain the radar composite interference signal.

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