Reconfigurable waveform generation method and device based on light injection semiconductor laser

Abstract

The invention discloses a reconfigurable waveform generation method based on a light injection semiconductor laser. Injecting a first path of optical signal output by the master laser into the semiconductor slave laser to enable the semiconductor slave laser to be in a single-period oscillation state, controlling the injection intensity to change periodically and linearly, and performing frequency shift processing on a second path of optical signal output by the master laser; and finally, performing frequency beating on the optical signal after frequency shift and the optical signal output by the semiconductor from the laser after the spurious signal is filtered out to obtain a broadband linear frequency modulation signal of which the frequency band is adjustable along with the frequency shift amount. The invention further discloses a reconfigurable waveform generation device based on the light injection semiconductor laser. Compared with the prior art, the frequency band tuning range of the generated signal can be effectively expanded.

Description

Technical Field

[0001] The present invention relates to a reconfigurable waveform generation method, and in particular to a reconfigurable waveform generation method and device based on light injection semiconductor laser. Background Art

[0002] With the increasing complexity of battlefield electromagnetic environments, the increase in stealth aircraft, and the intensification of ultra-low-altitude weapon threats, traditional radars are facing huge challenges. In 2006, Simon Haykin et al. from Canada first proposed the concept of cognitive radar (CR). (See [S. Haykin. Cognitive radar [J]. IEEE Signal Processing Magazine. 23 (1): 30-40, 2006.]) The core idea of cognitive radar is to enable the radar to dynamically adjust its operating mode according to target characteristics and environmental changes by combining intelligent decision-making and real-time perception. The most widely used broadband waveform signal in cognitive radar systems is the linear frequency modulation signal. Traditional electronic technology methods for generating linear frequency modulation signals mainly include analog and digital methods. The analog method usually uses a sawtooth voltage to drive a voltage-controlled oscillator to generate a linear frequency modulation signal. Due to the unstable starting RF phase of the voltage-controlled oscillator, the poor stability of the oscillator, and the large harmonic components in the signal, it is often necessary to rely on a complex phase-locked loop for frequency control. Digital methods include direct digital synthesis and waveform storage direct reading. The direct digital synthesis method uses a phase accumulator to obtain the quadratic phase of the linear frequency modulation signal. This phase value is then used to query a trigonometric table stored in memory, and the linear frequency modulation signal is obtained through digital-to-analog conversion. Due to phase truncation during the table lookup process, the signal contains high spurious levels, affecting the quality of the generated broadband waveform. The waveform storage direct reading method calculates the sampling values based on the target signal's bandwidth, time width, and other parameters using the mathematical expression of the linear frequency modulation signal. These values are then written sequentially into high-speed memory, and the waveform is directly generated through high-speed digital-to-analog conversion. This method consumes a lot of hardware circuit resources. Currently, the bandwidth and center frequency of broadband waveform signals based on electronic technology are relatively limited, making it difficult to meet the increasing bandwidth and center frequency requirements of high-performance microwave systems.

[0003] Photonic technology offers advantages such as high-speed processing, immunity to electromagnetic interference, and large instantaneous bandwidth, effectively overcoming the challenges faced by electronic methods. In recent years, numerous photonic-based approaches have been proposed to generate high-frequency, broadband microwave waveforms. Current methods can be broadly categorized into eight categories: frequency-time mapping, photonic phase modulation, optical heterodyning, optical frequency sweeping, photonic frequency doubling, photonic time-frequency splicing, photonic digital-to-analog conversion, and optical injection into semiconductor lasers. In frequency-time mapping, the broadband spectrum generated by a pulsed laser is first processed by a spectrum shaper. The shaped optical signal then passes through a dispersive element to achieve frequency-to-time domain mapping. However, the spectral response of the spectrum shaper is typically fixed, limiting the generated microwave signal parameters to fixed values or only slight adjustments. Photonic phase modulation generates linear frequency modulation signals by beating two coherent optical signals with a quadratic phase difference. In such systems, the time-bandwidth product of the generated signal typically does not exceed 10 due to the limited modulation coefficient of the electro-optical modulator. The optical heterodyne method generates a linear frequency modulated signal by beating a linearly chirped optical pulse signal with a continuous wave optical signal, or by beating two linearly chirped optical signals with different chirp rates. A disadvantage of this approach is the short duration of the generated waveform, typically a few nanoseconds to tens of nanoseconds, which limits its time-bandwidth product. The optical frequency sweeping method typically relies on two light beams of different wavelengths, one with a linearly varying frequency while the other maintains a constant frequency. By using the beat effect of a photodetector, a linear frequency modulated microwave signal can be generated. While this method can generate a signal with a large time-bandwidth product, its spectral purity is poor. The basic principle of the photonic frequency doubling method is to generate a high-frequency signal by processing a low-frequency baseband linear frequency modulated signal in the optical domain. Due to the limited extinction ratio of the modulator, the frequency doubling process generates spurious optical sidebands, which reduce the signal-to-noise ratio of the output RF signal. The photonic time-frequency splicing method leverages the rich spectrum resources of the optical domain and the flexibility of electrical signal generation. It generates baseband linear frequency modulation signals using electrical methods and combines them with optical techniques for time-frequency manipulation, enabling the synthesis of wide-bandwidth, long-duration radar waveforms from narrowband signals. When used to splice wide-bandwidth signals, phase discontinuities at the splicing point can impact subsequent applications and require further optimization. The photonic digital-to-analog conversion method generates arbitrary waveforms by designing different digital signal sequences and performing digital-to-analog conversion. The key lies in the implementation of a photonic digital-to-analog converter. However, since it is difficult to significantly increase the number of effective bits, it is difficult to achieve high-precision waveform generation with a wide dynamic range.

[0004] In the optical injection semiconductor laser scheme, the optical signal emitted by the master laser is injected into the semiconductor slave laser via an optical circulator. Under different perturbation conditions, the semiconductor laser output exhibits a variety of nonlinear dynamic states, including stable locking, period-one oscillation (P1), period-two oscillation (P2), and chaos oscillation. By setting appropriate injection parameters (injection frequency and intensity), the slave laser operates in the single-cycle oscillation state. After photodetection, the optical signal in the single-cycle oscillation state can be generated into a single-frequency microwave signal. By controlling the injection intensity using a control signal and an intensity modulator, the frequency of the redshifted wavelength component can be swept, thereby manipulating the instantaneous frequency of the generated microwave signal to produce the desired signal. However, the frequency adjustment of the linear frequency modulation signal generated by this scheme is limited by the injection parameters, which limits its flexibility. Furthermore, due to the influence of the laser's spontaneous emission noise, the microwave signal generated by the optical injection semiconductor laser structure also suffers from poor signal purity. Summary of the Invention

[0005] The technical problem to be solved by the present invention is to overcome the deficiency of the existing waveform generation technology based on light injection semiconductor lasers in that the frequency range of the generated signal is limited, and to provide a reconfigurable waveform generation method based on light injection semiconductor lasers, which can effectively expand the frequency band tuning range of the generated signal.

[0006] The present invention specifically adopts the following technical solutions to solve the above technical problems:

[0007] A reconfigurable waveform generation method based on light injection into a semiconductor laser involves injecting a first optical signal output by a master laser into a semiconductor slave laser, causing the semiconductor slave laser to be in a single-cycle oscillation state. The injection intensity is controlled to vary linearly and periodically, while frequency shifting is performed on a second optical signal output by the master laser. Finally, the frequency-shifted optical signal is beat with the optical signal output by the semiconductor slave laser after filtering out stray signals, resulting in a broadband linear frequency modulation signal whose frequency band is adjustable according to the frequency shift amount.

[0008] Furthermore, the reconfigurable waveform generation method based on light injection semiconductor laser further comprises: performing pre-distortion compensation on the injection intensity control signal according to the linearity deviation of the output broadband linear frequency modulation signal.

[0009] Preferably, the predistortion compensation method is as follows: by performing short-time Fourier transform on the output broadband linear frequency modulation signal, a frequency-time mapping relationship f of a certain single slope is extracted. actual (t); Use polynomial fitting to f actual (t) Perform nonlinear modeling and obtain f actual(t); substitute the ideal linear frequency function of the output broadband linear frequency modulation signal into the nonlinear model for reverse mapping compensation to obtain a corresponding distorted time function; map the distorted time function into a new injection intensity control signal, and use it to control the injection intensity.

[0010] Preferably, the frequency shift processing is achieved by performing carrier suppressed single sideband modulation on the second optical signal.

[0011] Preferably, the first optical signal is connected to the semiconductor slave laser via an intensity modulator, and the injection intensity is controlled by controlling the bias voltage of the intensity modulator.

[0012] Based on the same inventive concept, the following technical solutions can also be obtained:

[0013] A reconfigurable waveform generating device based on light injection semiconductor laser, comprising:

[0014] Light injection semiconductor laser, including a master laser and a semiconductor slave laser;

[0015] An intensity control module is used to inject the first optical signal output by the master laser into the semiconductor slave laser so that the semiconductor slave laser is in a single-cycle oscillation state, and control the injection intensity to change periodically and linearly;

[0016] A frequency shift module is used to perform frequency shift processing on the second optical signal output by the main laser;

[0017] An optical filter module, used to filter out stray signals from the output optical signal of the semiconductor laser;

[0018] The photoelectric detection module is used to beat the frequency of the frequency-shifted optical signal with the output optical signal of the semiconductor laser after filtering out stray signals, so as to obtain a broadband linear frequency modulation signal whose frequency band is adjustable according to the frequency shift amount.

[0019] Furthermore, the reconfigurable waveform generating device based on light injection semiconductor laser further includes:

[0020] The solution module is used to perform pre-distortion compensation on the injection intensity control signal according to the linearity deviation of the output broadband linear frequency modulation signal.

[0021] Preferably, the predistortion compensation method is as follows: by performing short-time Fourier transform on the output broadband linear frequency modulation signal, a frequency-time mapping relationship f of a certain single slope is extracted. actual (t); Use polynomial fitting to f actual (t) Perform nonlinear modeling and obtain f actual(t); substitute the ideal linear frequency function of the output broadband linear frequency modulation signal into the nonlinear model for reverse mapping compensation to obtain a corresponding distorted time function; map the distorted time function into a new injection intensity control signal, and use it to control the injection intensity.

[0022] Preferably, the frequency shift processing is achieved by performing carrier suppressed single sideband modulation on the second optical signal.

[0023] Preferably, the intensity control module includes:

[0024] an intensity modulator, configured to perform intensity modulation on the first optical signal;

[0025] The control signal generating module is used to generate an injection intensity control signal and input the injection intensity control signal into the bias voltage input port of the intensity modulator.

[0026] Compared with the prior art, the technical solution of the present invention and its further improved technical solution have the following beneficial effects:

[0027] The present invention improves the existing reconfigurable waveform generation technology based on light injection semiconductor lasers, performs frequency shift processing on the split signal of the injected light signal, and beats the frequency-shifted light signal with the output light signal of the semiconductor slave laser, thereby generating a broadband linear frequency modulation signal whose frequency band is adjustable according to the frequency shift amount, effectively expanding the frequency tuning range of the generated signal;

[0028] The present invention further performs pre-distortion compensation on the injection intensity control signal, thereby effectively eliminating the distortion of the generated signal and improving the linearity of the generated broadband linear frequency modulation signal. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 This is a block diagram of the structural principle of the reconfigurable waveform generating device based on light injection semiconductor laser of the present invention;

[0030] Figure 2 This is a schematic structural diagram of a specific embodiment of a reconfigurable waveform generating device based on light injection semiconductor lasers of the present invention;

[0031] Figures 3 to 5 is the result of the effect verification experiment, Figure 3 is the time-frequency diagram of the signal generated without predistortion compensation, Figure 4 Time-frequency diagram of the signal generated for predistortion compensation, Figure 5 This is the time-frequency diagram of the signal generated by shifting the local oscillator by 15 GHz. DETAILED DESCRIPTION

[0032] In response to the deficiency of the existing waveform generation technology based on light injection semiconductor lasers in that the frequency range of the generated signal is limited, the solution of the present invention is to improve the existing reconfigurable waveform generation technology based on light injection semiconductor lasers, perform frequency shift processing on the beam splitting signal of the injected light signal, and beat the frequency of the frequency-shifted light signal with the output light signal of the semiconductor slave laser, thereby generating a broadband linear frequency modulation signal whose frequency band is adjustable with the frequency shift amount, thereby effectively expanding the frequency band tuning range of the generated signal.

[0033] The present invention proposes a reconfigurable waveform generation method based on light injection into a semiconductor laser, specifically as follows:

[0034] The first optical signal output by the master laser is injected into the semiconductor slave laser to put the semiconductor slave laser into a single-cycle oscillation state, and the injection intensity is controlled to change linearly and periodically. At the same time, the second optical signal output by the master laser is frequency-shifted. Finally, the frequency-shifted optical signal is beat with the output optical signal of the semiconductor slave laser after filtering out stray signals to obtain a broadband linear frequency modulation signal with an adjustable frequency band according to the frequency shift amount.

[0035] The reconfigurable waveform generation device based on light injection semiconductor laser proposed in the present invention includes:

[0036] Light injection semiconductor laser, including a master laser and a semiconductor slave laser;

[0037] An intensity control module is used to inject the first optical signal output by the master laser into the semiconductor slave laser so that the semiconductor slave laser is in a single-cycle oscillation state, and control the injection intensity to change periodically and linearly;

[0038] A frequency shift module is used to perform frequency shift processing on the second optical signal output by the main laser;

[0039] An optical filter module, used to filter out stray signals from the output optical signal of the semiconductor laser;

[0040] The photoelectric detection module is used to beat the frequency of the frequency-shifted optical signal with the output optical signal of the semiconductor laser after filtering out stray signals, so as to obtain a broadband linear frequency modulation signal whose frequency band is adjustable according to the frequency shift amount.

[0041] On this basis, in order to improve the linearity of the generated linear frequency modulation signal, the present invention also proposes the following further improvement scheme: pre-distortion compensation is performed on the injection intensity control signal according to the linearity deviation of the output broadband linear frequency modulation signal.

[0042] To facilitate public understanding, the technical solution of the present invention is described in detail below through a specific embodiment with reference to the accompanying drawings:

[0043] The basic structural principle of the reconfigurable waveform generating device based on light injection semiconductor laser in this embodiment is as follows: Figure 1 As shown, a frequency shift module and a solution module are added to the traditional reconfigurable waveform generation device based on light injection semiconductor laser; wherein, the frequency shift module is used to perform frequency shift processing on a beam splitting signal of the main laser output optical signal, and then beat the frequency-shifted optical signal with the output optical signal of the semiconductor slave laser after filtering out the stray signal, so as to obtain a broadband linear frequency modulation signal whose frequency band is adjustable with the frequency shift amount; the solution module is used to perform feedback correction on the injection intensity control signal according to the linearity deviation of the output broadband linear frequency modulation signal to achieve pre-distortion compensation.

[0044] Figure 2 A specific implementation structure of the device is shown, such as Figure 2 As shown, it includes 1 master laser, 1 slave laser, 1 arbitrary waveform generator, 2 Mach-Zehnder modulators, 2 optical filters, 2 optical amplifiers, 1 polarization controller, a circulator, a microwave source, a balanced photodetector, a spectrum analyzer and an oscilloscope.

[0045] Among them, the master laser, slave laser, arbitrary waveform generator, Mach-Zehnder modulator 2, optical amplifier 2, optical filter 2 and polarization controller are the components required for a traditional reconfigurable waveform generation device based on a light injection semiconductor laser; an optical signal output by the master laser is injected into the slave laser as an injection optical signal after passing through the Mach-Zehnder modulator 2 and the optical amplifier 2, and the injection intensity control signal generated by the arbitrary waveform generator is input into the bias voltage input port of the Mach-Zehnder modulator 2 to control the injection intensity. The injection optical signal passes through the circulator and is injected into the slave laser through the polarization controller, exciting a single-cycle oscillation state in the slave laser; the output optical signal of the slave laser enters the optical filter 2 through the circulator to filter out spurious signals such as the carrier, high-order sidebands and noise.

[0046] like Figure 2 As shown, the frequency shift module of this embodiment consists of a microwave source, a Mach-Zehnder modulator 1, an optical filter 1, and an optical amplifier 1. The single-frequency microwave signal generated by the microwave source is modulated by the Mach-Zehnder modulator 1 on another optical signal output by the main laser. The bias voltage of the Mach-Zehnder modulator 1 is adjusted to make it operate in a carrier suppression mode, thereby generating a carrier-suppressed double-sideband modulated signal. Then, one sideband is filtered out by the optical filter 1, and the remaining carrier-suppressed single-sideband modulated signal is amplified and output by the optical amplifier 1.

[0047] The balanced photodetector constitutes a photodetection module, and the output optical signal of the optical filter 2 is beat by the output optical signal of the optical amplifier 1 to obtain a broadband linear frequency modulation signal whose frequency band is adjustable according to the frequency shift amount of the frequency shift module.

[0048] In this embodiment, an oscilloscope and a spectrum analyzer are used as solution modules to detect the time domain characteristics of the electrical signal after photoelectric conversion. According to the linearity deviation of the output broadband linear frequency modulation signal, the injection intensity control signal is feedback-corrected to achieve pre-distortion compensation.

[0049] In order to generate a linear frequency modulation signal, the control signal V(t) is connected to the bias terminal of the Mach-Zehnder modulator to control the injection intensity control signal ξ. The waveform of V(t) in one cycle can be expressed as

[0050]

[0051] Where V and T are the amplitude and period of the control signal, respectively. The injection intensity ξ can be expressed as

[0052]

[0053] Among them A inj (t) and A SL are the electric field amplitudes of the injected light and the free resonance laser, respectively. H is the amplitude transfer function of the Mach-Zehnder modulator, so the output microwave signal frequency f o It can be expressed as

[0054]

[0055] Where k is a constant. It can be seen that when the light injection semiconductor laser operates in a single cycle oscillation state, when the injection intensity ξ increases linearly with time, the single cycle oscillation frequency f o The frequency of the microwave signal generated by photoelectric detection will also increase linearly with time. Therefore, the instantaneous frequency of the microwave signal generated by photoelectric detection will also increase linearly with time, that is, a linear frequency modulation signal is generated. The frequency range of the linear frequency modulation signal obtained by direct photoelectric conversion according to the traditional method is:

[0056]

[0057] In the frequency shift module, the frequency shift of the optical local oscillator is realized in the form of a cascaded intensity modulator and an optical filter. First, the signal frequency f1 generated by the microwave source is set according to the required broadband waveform frequency band, and the signal is loaded onto the modulator. By adjusting the bias voltage of the Mach-Zehnder modulator 1 to make it work in carrier suppression mode, the carrier component is removed and only the modulated sideband is retained. Subsequently, a specific sideband, such as the +1st or -1st order sideband, is selected through the optical filter 1 to realize the single-sideband modulation function. By adjusting the frequency f1 of the microwave source output signal and the passband of the optical filter, the frequency offset area can be precisely controlled, thereby realizing precise adjustment of the signal spectrum characteristics and ensuring that the output signal meets the predetermined design requirements. The broadband waveform signal and the frequency-shifted signal generated by the two branches are processed by the photodetector beat frequency to obtain a broadband linear frequency modulation signal with adjustable frequency band. After adding the frequency shift module, the frequency range of the linear frequency modulation signal is:

[0058]

[0059] Obviously, the frequency tunable range of the generated broadband linear FM signal is greatly expanded.

[0060] Due to the nonlinearity of the amplitude transfer function of the Mach-Zehnder modulator and the nonlinearity of the internal perturbations of the semiconductor laser, the frequency of the output signal is not strictly proportional to the magnitude of the control signal voltage. Therefore, the present invention uses a solver module to perform pre-distortion compensation on the injection intensity control signal to improve the linearity of the linear frequency modulation signal obtained by the optical injection technology, thereby optimizing its performance. The implementation process is as follows:

[0061] The optical injection system is used to generate the initial linear frequency modulation signal, and the output signal at the modulation port is collected by a real-time oscilloscope. The signal is subjected to short-time Fourier transform to extract the frequency-time mapping relationship f of a certain single slope (such as the rising segment). actua l(t).

[0062] The relationship between the measured frequency and time often has nonlinear deviations, which can be expressed as:

[0063] f actual (t)=f0+kt+ε(t)

[0064] Where ε(t) is a nonlinear error term. To analyze its characteristics, a polynomial fit is used to fit f actual (t) Modeling and finding the optimal fitting order N to obtain f actual (t) is a nonlinear model, namely:

[0065]

[0066] The desired ideal linear frequency function is:

[0067] f ideal (t)=f0+kt,t∈[0,T]

[0068] Substitute this function into the inverse function of the nonlinear model t = F -1 (f actual ), implement reverse mapping compensation:

[0069]

[0070] The obtained t pre (t) is a “distorted time” function, which is used to “fold back” the ideal linear frequency function to the original nonlinear response path through the inverse system modeling function, thereby restoring the linear frequency modulation output in the real system.

[0071] The reverse mapped warped time function t pre (t) is mapped to the modulation voltage V'(t) in the following form:

[0072]

[0073] This voltage signal is the predistorted waveform, which is loaded into the Mach-Zehnder modulator 2 through an arbitrary waveform generator to achieve control of the light injection laser.

[0074] In order to verify the technical effect of the technical solution of the present invention, the above specific embodiments were experimentally verified. The key parameters used in the experiment are shown in Table 1:

[0075] Table 1 Key experimental parameters

[0076]

[0077] During the experiment, the DFB laser was heated to a temperature of DFB =24.8°C, bias current I = 85.8mA, its output frequency is f2 = 193.5524THz, and its output power is P2 = 10.56dBm. The output frequency of the tunable laser is f1 = 193.5630THz. The frequency difference between the external laser light injected into the DFB laser and its free-running frequency is Δf = f1-f2 = 10.6GHz. Simultaneously, a triangular wave with a period of T controls the Mach-Zehnder modulator, causing periodic modulation of the injected laser power, which is then amplified by the EDFA. A certain power difference forms between the injected optical power P1 and the DFB laser's output power P2 in its free-running state. When the frequency and power differences are well matched, the DFB laser enters a stimulated oscillation state (P1 oscillation state), generating a -1st-order sideband signal at its output that varies with period T. The carrier and the -1st-order sideband are then subjected to beat frequency processing to produce a double-chirped linear frequency modulation signal. Figure 3The time-frequency diagram of the generated signal shows that the linearity of the directly generated signal is poor. According to the above pre-distortion compensation mechanism, the signal generated by the arbitrary waveform generator is corrected. The corrected signal is shown in Figure 4 As shown in Figure 1, a linear frequency modulation signal with a frequency range of 15.67–25.76 GHz was successfully generated. On this basis, in the frequency shift branch, the microwave source modulated the 15 GHz signal into the optical path, achieving a 15 GHz frequency shift of the local oscillator. The signal generated after the frequency shift is as follows: Figure 5 As shown in the figure, due to the insertion loss caused by the frequency shift, the bandwidth of the signal is slightly narrowed, and finally a linear frequency modulation signal of 1.73-10.61 GHz is generated, thereby verifying the feasibility and effectiveness of the scheme of the present invention in generating broadband reconfigurable waveforms.

Claims

1. A reconfigurable waveform generation method based on light injection semiconductor laser, characterized in that: The first optical signal output by the master laser is injected into the semiconductor slave laser to put the semiconductor slave laser into a single-cycle oscillation state, and the injection intensity is controlled to change linearly and periodically. At the same time, the second optical signal output by the master laser is frequency-shifted. Finally, the frequency-shifted optical signal is beat with the output optical signal of the semiconductor slave laser after filtering out stray signals to obtain a broadband linear frequency modulation signal with an adjustable frequency band according to the frequency shift amount.

2. The reconfigurable waveform generation method based on light injection into a semiconductor laser according to claim 1, wherein: Also includes: Predistortion compensation is performed on the injection intensity control signal according to the linearity deviation of the output broadband linear frequency modulation signal.

3. The reconfigurable waveform generation method based on light injection into a semiconductor laser according to claim 1, wherein: The method of predistortion compensation is as follows: by performing short-time Fourier transform on the output broadband linear frequency modulation signal, a frequency-time mapping relationship f of a certain single slope is extracted. actual (t); Use polynomial fitting to f actual (t) Perform nonlinear modeling and obtain f actual (t); substitute the ideal linear frequency function of the output broadband linear frequency modulation signal into the nonlinear model for reverse mapping compensation to obtain a corresponding distorted time function; map the distorted time function into a new injection intensity control signal, and use it to control the injection intensity.

4. The reconfigurable waveform generation method based on light injection semiconductor laser according to any one of claims 1 to 3, characterized in that: The frequency shift processing is achieved by performing carrier suppressed single sideband modulation on the second optical signal.

5. The reconfigurable waveform generation method based on light injection semiconductor laser according to any one of claims 1 to 3, characterized in that: The first optical signal is connected to the semiconductor slave laser via an intensity modulator, and the injection intensity is controlled by controlling the bias voltage of the intensity modulator.

6. A reconfigurable waveform generation device based on light injection semiconductor laser, characterized in that: include: Light injection semiconductor laser, including a master laser and a semiconductor slave laser; An intensity control module is used to inject the first optical signal output by the master laser into the semiconductor slave laser so that the semiconductor slave laser is in a single-cycle oscillation state, and control the injection intensity to change periodically and linearly; A frequency shift module is used to perform frequency shift processing on the second optical signal output by the main laser; An optical filter module, used to filter out stray signals from the output optical signal of the semiconductor laser; The photoelectric detection module is used to beat the frequency of the frequency-shifted optical signal with the output optical signal of the semiconductor laser after filtering out stray signals, so as to obtain a broadband linear frequency modulation signal whose frequency band is adjustable according to the frequency shift amount.

7. The reconfigurable waveform generating device based on light injection semiconductor laser according to claim 6, characterized in that: Also includes: The solution module is used to perform pre-distortion compensation on the injection intensity control signal according to the linearity deviation of the output broadband linear frequency modulation signal.

8. The reconfigurable waveform generating device based on light injection semiconductor laser according to claim 7, characterized in that: The method of predistortion compensation is as follows: by performing short-time Fourier transform on the output broadband linear frequency modulation signal, a frequency-time mapping relationship f of a certain single slope is extracted. actual (t); Use polynomial fitting to f actual (t) Perform nonlinear modeling and obtain f actual (t); substitute the ideal linear frequency function of the output broadband linear frequency modulation signal into the nonlinear model for reverse mapping compensation to obtain a corresponding distorted time function; map the distorted time function into a new injection intensity control signal, and use it to control the injection intensity.

9. The reconfigurable waveform generating device based on light injection semiconductor laser according to any one of claims 6 to 8, characterized in that: The frequency shift processing is achieved by performing carrier suppressed single sideband modulation on the second optical signal.

10. The reconfigurable waveform generating device based on light injection semiconductor laser according to any one of claims 6 to 8, characterized in that: The intensity control module includes: an intensity modulator, configured to perform intensity modulation on the first optical signal; The control signal generating module is used to generate an injection intensity control signal and input the injection intensity control signal into the bias voltage input port of the intensity modulator.

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