CN110265854B - Light guide self-adaptive narrow-spectrum microwave generation method based on high-energy pulse cluster laser - Google Patents

Abstract

The invention discloses a light-guide adaptive narrow-spectrum microwave generating method based on high-energy pulse cluster laser, and aims to solve the problems of large volume, single frequency point and difficult frequency adjustment of the microwave generating device of the existing microwave generating method. The technical solution is to first construct a light-guide adaptive narrow-spectrum microwave generator composed of a high-energy pulse cluster laser, a voltage source, a wide-bandgap semiconductor device and a radiation output component; , envelope waveform, high-energy pulse cluster laser with adjustable GHz high-frequency pulse repetition frequency; the voltage source is a solid-state pulse forming line, which generates a pulse voltage and acts on the wide-bandgap semiconductor device; the wide-bandgap semiconductor device acts at the same time as the laser and the voltage The high-frequency electrical signal is generated under the radiation output component; the high-frequency electrical signal is radiated by the radiation output component, and the microwave signal is output. The invention can solve the problems of large volume, single frequency point and difficult frequency adjustment of the microwave generating device.

Description

A lightguide adaptive narrow-spectrum microwave generation method based on high-energy pulsed cluster laser

technical field

The invention relates to a high-power microwave generating method-a narrow-spectrum microwave generating method based on high repetition frequency pulsed laser light and wide band gap optical semiconductor.

Background technique

High-power microwaves interfere, disrupt, and damage the electronic information systems of equipment through strong electromagnetic radiation, degrade or fail their functions, and can effectively improve information confrontation capabilities.

In order to cope with the increasingly complex electromagnetic environment of threat targets in the field of information technology and the continuous emergence of new waveforms and new spectrums, it is urgent to develop a new adaptive directed energy microwave generation method with flexible and adjustable parameters. Traditional high-power microwave generation methods are based on pulsed power devices and relativistic electric vacuum devices, which have been developed for 40-50 years. The output microwave parameters are usually fixed, and the frequency point is single or difficult to adjust. This is because relativistic vacuum devices usually have a narrow operating frequency range and are mechanical structures that are difficult to adjust. Moreover, the electric vacuum device needs to operate in a vacuum environment, resulting in the large size of the microwave generating device designed by this method.

The use of photoconductive semiconductors to generate microwaves is a new direction that has been studied more in recent years. At present, domestic and foreign public reports are all using photoconductive semiconductors as fast cut-off switches, that is, using the fast turn-on properties of photoconductive semiconductor switches to generate a steep frontier pulse voltage , and then radiate to produce broadband or ultra-broadband signals, and the photoconductive semiconductors in these reports act like switching oscillators. For example, the document "Photoconductive Switch-Based HPM for Airborne Counter-IED Applications (photoconductive switch-based high-power microwave generator for airborne counter-improvised explosive devices), IEEE Transactions on Plasma Science (IEEE Transactions on Plasma Science), 2014, 42, Vol. 5, pp. 1285-1294" is a method of making a broadband microwave signal generator using the conduction characteristics of photoconductive switches. The electrical signal with a steep rising edge is then radiated by a broadband antenna to generate a broad-spectrum signal; since the energy of the broad-spectrum is dispersed in frequency, and the low-frequency component is limited by the size of the antenna, directional radiation is relatively difficult, so the generated microwave power "equivalent radiation power" Therefore, the microwave power generated by this solution is low, and the microwave signal output by this solution is in the order of one hundred watts.

SUMMARY OF THE INVENTION

The technical problem to be solved by the present invention is that, in view of the problems that the microwave generating device used in the existing method for generating microwaves by using an electric vacuum device is large in volume, single frequency point and difficult to adjust the frequency, a new method based on high repetition frequency pulsed laser is proposed. Light guide adaptive narrow-spectrum microwave generation method. Utilize the linear working mode of wide-bandgap photoconductive semiconductor devices at high voltage and high current level (in the linear working mode, a photon is incident into the device, and a pair of hole-electron pairs is generated in the device, and the electrons are in the electric field generated by the applied voltage. The current generated by this mode has the same waveform and frequency as the incident laser. Under the applied bias voltage, the high-frequency laser irradiates the wide-bandgap photoconductive semiconductor device to generate high-frequency electrical signals. , and radiate the output to generate a microwave signal.

The specific technical scheme of the present invention includes the following steps:

The first step is to build a light-guide adaptive narrow-spectrum microwave generator. The microwave generator consists of a circuit modulation module and an optical path modulation module. The optical path modulation module is a high-energy pulsed cluster laser that can be used as a signal source for light-guiding devices in microwave systems. , referred to as high-energy pulse cluster laser, the circuit modulation module consists of three parts: voltage source, wide band gap semiconductor device and radiation output component. High-energy pulsed cluster lasers are connected with wide-bandgap semiconductor devices using optical fibers or optical waveguides.

High-energy pulse cluster lasers generate lasers with adjustable pulse cluster repetition frequency, pulse width, envelope waveform, and GHz high-frequency pulse repetition frequency, which are input into wide-bandgap semiconductor devices through optical fibers or optical waveguides.

The high-energy pulse cluster laser consists of a laser seed source, a fiber preamplifier, an optical modulation module, a high-frequency signal source, a synchronous control circuit, a fiber amplifier, and 2 editable waveform signal boards (namely, the first editable waveform signal board and the second editable waveform signal board). waveform signal board). The optical modulation module is composed of an acousto-optic modulator and an electro-optical intensity modulator, and the acousto-optical modulator and the electro-optical intensity modulator are connected by means of a fiber splicing device pigtail. The output end of the laser seed source and the input end of the fiber pre-amplifier, the output end of the fiber pre-amplifier and the fiber input end of the optical modulation module (ie the fiber input end of the acousto-optic modulator), the output end of the optical modulation module (ie the electro-optical intensity The optical fiber output end of the modulator) and the input end of the optical fiber amplifier are connected by optical fiber fusion, and the output end of the optical fiber amplifier is fused with an end cap or an isolator. And the signal input end of the laser seed source is connected with the signal output end of the first editable waveform signal board through a coaxial signal line; the external trigger signal input end of the first editable waveform signal board and the first output end of the synchronous control circuit pass through The coaxial signal line is connected; the external trigger signal input end of the second editable waveform signal board is connected with the second output end of the synchronization control circuit through the coaxial signal line, and the signal output end of the second editable waveform signal board is connected with the acousto-optic modulation The signal input end of the device is connected by a coaxial signal line. The radio frequency signal input end of the electro-optical intensity modulator is connected with the signal output end of the high frequency signal source by a coaxial signal line.

The synchronization control circuit provides synchronization timing signals for the first editable waveform signal board and the second editable waveform signal board. The first synchronization timing signal output from the first output terminal of the synchronization control circuit is used to trigger the first editable waveform signal board, and the second synchronization timing signal output from the second output terminal is used to trigger the second editable waveform signal board. It is required that the 2-way synchronous timing signal is a standard digital trigger signal with adjustable pulse width, adjustable repetition frequency, and an amplitude of 2.5V to 5V, and the time jitter between the first and second synchronous timing signal pulses is less than 5ns.

The first editable waveform signal board is an external trigger working mode. When the first synchronization timing signal is received from the synchronization control circuit, the electric pulse width is edited according to the requirements of the microwave system light guide device for the signal source pulse width, and the laser seed source is sent to the laser seed source. Send a rectangular signal with adjustable repetition frequency and pulse width.

The laser seed source adopts a semiconductor pulse laser seed source, which can generate a laser with flexible and adjustable pulse repetition frequency, pulse width, amplitude and time domain waveform according to the rectangular signal output by the editable waveform signal board. Seed pulse. It is required that the center wavelength range of the semiconductor pulse laser seed source is 1030nm～1065nm, the pulse width range is 10ns～200ns, and the repetition frequency range is 10Hz～200kHz.

The fiber pre-amplifier enhances the power of the laser seed pulse generated from the laser seed source, and improves the signal-to-noise ratio of the high-energy pulse cluster laser. The fiber pre-amplifier is composed of M (M≥1) grade fiber amplifier. The average power and peak power of the output laser pulse of the fiber preamplifier are required to be less than or equal to the maximum withstand power of the electro-optic intensity modulator.

The second editable waveform signal board is in an external trigger working mode, and sends a preset waveform electrical signal to the acousto-optic modulator when receiving the second synchronization timing signal from the synchronization control circuit.

The gain saturation effect of the fiber preamplifier and fiber amplifier will cause the amplified laser pulse waveform to be different from the input laser pulse waveform they receive, that is, the amplified laser pulse waveform will be distorted. In order to be used as the signal source of the photoconductive device of the microwave system, the present invention needs to output a rectangular envelope pulse cluster laser (that is, the fiber amplifier of the present invention must output a rectangular envelope pulse cluster laser), so it is necessary to preset the waveform of the input signal of the fiber amplifier, This is achieved by sending a preset waveform electrical signal to the acousto-optic modulator through an editable waveform signal board.

The acousto-optic modulator is a fiber-coupled acousto-optic modulator with a bandwidth greater than 100 MHz. On the one hand, the acousto-optic modulator receives a preset waveform electrical signal from the second editable waveform signal board, modulates the optical pulse waveform output by the optical fiber preamplifier into a preset time-domain waveform optical pulse, and sends the preset time-domain waveform optical pulse To the electro-optical intensity modulator; on the other hand, the acousto-optical modulator turns off the continuous spontaneous emission noise between the optical pulses output by the fiber preamplifier.

The high-frequency signal source is used to provide the electro-optical intensity modulator with a high-frequency sinusoidal signal of GHz order with flexible and adjustable frequency. The high-frequency signal source can be any one of VCO, frequency synthesizer, arbitrary waveform generator, and function generator, or it can be VCO, frequency synthesizer, arbitrary waveform generator, function generator, etc. Any combination of generator and power amplifier. The voltage output by the high frequency signal source is required to be greater than the half-wave voltage of the electro-optical intensity modulator.

The working bandwidth of the electro-optical intensity modulator is greater than or equal to 10 GHz. According to the high-frequency sinusoidal signal output by the high-frequency signal source, the electro-optic intensity modulator modulates the preset time-domain waveform light pulse received from the acousto-optic modulator into a preset envelope waveform pulse cluster laser, so that the preset envelope waveform pulse cluster The repetition frequency and waveform of the high-frequency pulse in the laser are the same as the high-frequency sinusoidal signal received from the high-frequency signal source, and the modulated pulse cluster laser is sent to the fiber amplifier.

The fiber amplifier amplifies the pulse cluster laser with preset envelope waveform received from the electro-optical intensity modulator, and outputs a rectangular envelope pulse cluster. The fiber amplifier consists of N (N≥2) grade fiber amplifiers. The output end of the fiber amplifier is welded with a fiber end cap or isolator to prevent the damage to the high-energy pulse cluster laser caused by the return light from the end face.

The voltage source is a solid-state pulse forming wire, which is connected with the electrode of the wide-bandgap semiconductor device by conductive silver paste, and generates a pulse voltage which acts on the wide-bandgap semiconductor device.

The wide-bandgap semiconductor device is connected to the high-energy pulse cluster laser through an optical fiber or an optical waveguide, to a voltage source through a conductive silver paste, and to a radiation output component through a coaxial line. Under the simultaneous action of the laser and the voltage, a high-frequency electrical signal is generated. And output the high-frequency electrical signal to the radiation output component.

The wide-bandgap semiconductor device is composed of four parts: a semiconductor wafer (ie, a substrate), 2 electrodes, a filling material and a supporting structure. The combination of the semiconductor wafer 8 and the 2 electrodes is connected, and the patent application No. 201710616299.7 "Opposite positive light type" The "opposite positive light-type high-power photoconductive switching device" described in "High-power photoconductive switching device and its manufacturing method" has the same structure: using a high-resistance semiconductor as a substrate material, a transparent conductive layer is prepared on the high-resistance semiconductor (the front side) , Prepare a high-voltage passivation layer with anti-reflection effect on the transparent conductive layer. There is a metal ring around the high-voltage passivation layer that is close to the transparent conductive layer, and then connected to the hollow metal electrode (that is, the top of the metal ring is close to the hollow Metal electrodes); the back of the high resistance semiconductor is first prepared with a silver-plated layer with high inverse performance, and then connected with the solid metal electrodes. The hollow metal electrode and the solid metal electrode are the two electrodes in the present invention, and the rest (ie, the substrate material, the transparent conductive layer, the high-voltage passivation layer, the metal ring, and the silver-plated layer) are the semiconductors used in the present invention. wafer. The semiconductor wafer can be a square sheet or a circular sheet, with a thickness of 0.01 mm to 10 mm, a side length of 1 mm to 50 mm when it is a square sheet, and a diameter of 1 mm to 50 mm when it is a circular sheet. The semiconductor wafer substrate material, that is, a high-resistance semiconductor, selects a wide-bandgap SiC material, such as 4H-SiC or 6H-SiC material, with a withstand voltage requirement of 3-4MV/cm, and the recombination time of SiC crystal carriers is less than 1ns. The material of the hollow metal electrode and the solid metal electrode can be stainless steel or brass; the ratio of the diameter of the hollow metal electrode and the solid metal electrode to the side length or diameter of the semiconductor wafer is kept between 1 and 1.5; The connection of semiconductor wafers is bonded by conductive silver glue, and the silver glue is cured after baking. The support structure is a rectangular box without a cover made of PTFE material, the hollow metal electrode passes through the first side of the support structure, one end is bonded to the first surface of the semiconductor wafer, and the other end is connected to the voltage source; the solid metal electrode One end is bonded to the second side of the semiconductor wafer (a side opposite to the first side), and the other end passes through the second side of the support structure and is connected to a voltage source; the semiconductor wafer 8, hollow metal electrodes, solid metal electrodes and There is a filling material between the support structures. The filling material needs to completely cover the semiconductor wafer, hollow metal electrode, and solid metal electrode. The filling material 100 requires an average withstand field strength of ≥40kV/mm. When the light wavelength is 200nm ~ 1200nm, the transmission of light If the ratio is greater than 99%, the filling material is preferably epoxy resin.

The voltage source is a solid state pulse forming wire. The withstand voltage range of the solid-state pulse-forming line should be the same as that of the wide-bandgap semiconductor device, and the impedance of the solid-state pulse-forming line is the same as the minimum on-state resistance of the wide-bandgap semiconductor device under laser irradiation. The solid-state pulse forming line has a structure of three flat plates, which are stacked together according to the structure of metal plate-medium-metal plate-medium-metal plate. The medium is a dielectric material with high energy storage density (>1J/cm ³ ), and the metal plate material is silver. The connection method of the voltage source and the wide band gap semiconductor device is as follows: two electrodes of the wide band gap semiconductor device, the middle metal plate and the upper metal plate of the voltage source can be respectively connected, and the two electrodes can also be connected to the middle metal plate and the lower metal plate of the voltage source.

The radiation output component is a flat-panel broadband radiating horn that matches the impedance of the voltage source. It is connected to the wide-bandgap semiconductor device through the SMA (SubMiniature version A) coaxial line, and radiates the high-frequency electrical signal output by the wide-bandgap semiconductor device to generate microwave signals. output.

In the second step, the high-energy pulse-cluster laser generates high-energy pulse-cluster laser, and outputs the high-energy pulse-cluster laser to the wide-bandgap semiconductor device. The high-energy pulse-cluster laser repetition frequency, pulse width, envelope waveform, and GHz high-frequency pulse repetition frequency can be used. Tuning is done by:

2.1, the synchronous control circuit outputs 2 digital signals with adjustable repetition frequency;

2.2. The first editable waveform signal board is triggered by the first synchronizing signal output by the synchronous control circuit. According to the parameter requirements of the light guide device of the microwave system for the pulse width of the signal source, the electrical pulse width of the first editable waveform signal board is edited and sent to the laser. The seed source sends a rectangular signal with adjustable pulse width;

2.3. The laser seed source receives the rectangular signal with adjustable pulse width output by the first editable waveform signal board, and generates a rectangular optical pulse with adjustable pulse width, and the repetition frequency and pulse width of this optical pulse can be adjusted;

2.4. The fiber pre-amplifier amplifies the energy of the rectangular light pulse output by the laser seed source to a level that does not exceed the maximum acceptable power of the electro-optical intensity modulator to improve the signal-to-noise ratio. The output laser pulse waveform is characterized by the distortion of the waveform due to the gain saturation effect. ;

2.5. The second editable waveform signal board is triggered by the synchronization control circuit outputting the second synchronous signal, and outputs a rectangular electrical signal with the same pulse width as the first editable waveform signal board.

2.6. The acousto-optic modulator receives a rectangular electrical signal with the same pulse width as the first editable waveform signal board from the second editable waveform signal board, that is, the laser pulse waveform output by the fiber preamplifier is not changed, and the time domain waveform is not changed. The laser pulses are sent to the electro-optical intensity modulator;

2.7, the high-frequency signal source outputs a high-frequency sinusoidal signal with a flexible and adjustable frequency of the order of GHz;

2.8. The electro-optical intensity modulator modulates the laser pulse with the unchanged time-domain waveform received from the acousto-optic modulator into a pulse-cluster laser with the same envelope waveform according to the high-frequency sinusoidal signal received from the high-frequency signal source, so that the high The repetition frequency and waveform of the high-frequency pulse are the same as the high-frequency sinusoidal signal received from the high-frequency signal source, and the pulse cluster laser is sent to the fiber amplifier;

2.9. Test the input pulse cluster laser envelope waveform, output pulse cluster laser envelope waveform and pulse cluster laser energy of the fiber amplifier. The time-dependent input is calculated from the pulse cluster energy, the input pulse cluster envelope waveform and the output pulse cluster envelope waveform. The instantaneous power of the pulse cluster P _in (t and the instantaneous power of the time-dependent output pulse cluster P _out (t) are imported into the Matlab program (including the stochastic parallel gradient descent algorithm) to extract the envelope waveform, which is used as the initial input and output waveform to calculate The time-dependent gain curve is obtained, and the initial gain G ₀ and the saturated energy flow E _sat parameter of the amplifier are obtained by curve fitting of formula (1). Then the rectangular envelope waveform is set as the target output envelope waveform, and the Matlab program is run to obtain the pre-set value. Set a waveform electrical signal; the preset waveform electrical signal is obtained by the following methods:

2.9.1. Set the output signal of the second editable waveform signal board to a rectangle, that is, the output signal of the second editable waveform signal board makes the acousto-optic modulator not change the laser pulse waveform output by the fiber preamplifier. Under these conditions, the input burst envelope waveform, output burst envelope waveform and burst energy E _out (t) of the fiber amplifier were tested with a high-speed oscilloscope, photodetector and power meter. The time-dependent input pulse cluster instantaneous power P _in (t) and the time-dependent output pulse cluster instantaneous power P _out (t) are obtained by calculating the envelope waveform and the output pulse cluster envelope waveform, where t is time.

2.9.2, import the obtained time-dependent input pulse cluster instantaneous power P _in (t) and time-dependent output pulse cluster instantaneous power P _out (t) into the Matlab program, extract the envelope waveform , as the stochastic parallel gradient descent algorithm to calculate the prediction The initial input and output waveforms when the waveform is compensated.

2.9.3, the time-dependent gain function G(t) is calculated by the formula G(t)=P _out (t)/P _in (t). According to the gain formula (1) in the amplifier FN model,

G(t)=1+(G ₀ -1)exp[-E _out (t)/E _sat ] (1)

Curve fitting obtains the initial gain G ₀ and the saturation energy flow E _sat parameter of the amplifier;

2.9.4, set the rectangular envelope waveform as the target output envelope waveform of the Matlab program, and normalize the target output rectangular envelope waveform;

2.9.5, run the MATLAB program to get the preset waveform.

2.10. Edit the output pulse waveform of the second editable waveform signal board according to the preset waveform electrical signal, so that the second editable waveform signal board outputs the preset waveform electrical signal to the acousto-optic modulator.

2.11, the acousto-optic modulator receives a preset waveform electrical signal from the second editable waveform signal board, and modulates the optical pulse waveform output by the optical fiber preamplifier into a preset time-domain waveform optical pulse, which is characterized in that the waveform is calculated through the above steps. The preset waveform can make the pulse cluster envelope waveform output by the fiber amplifier be rectangular, and the preset time-domain waveform optical pulse can be sent to the electro-optical intensity modulator.

2.12, the electro-optical intensity modulator modulates the preset time-domain waveform light pulse received from the acousto-optical modulator into a preset envelope waveform pulse cluster laser according to the high-frequency sinusoidal signal received from the high-frequency signal source, which is characterized by a pulse cluster form , and the pulse cluster envelope is a preset waveform, so that the repetition frequency and waveform of the high-frequency pulse in the pulse cluster laser with the preset envelope waveform are the same as the high-frequency sinusoidal signal received from the high-frequency signal source, and the modulated pulse cluster is The laser is sent to the fiber amplifier;

2.13, the fiber amplifier amplifies the preset envelope waveform pulse cluster laser received from the electro-optic intensity modulator, and outputs high-energy pulse cluster laser to the wide-bandgap semiconductor device. The pulse cluster laser repetition frequency, pulse width, envelope waveform, GHz high Frequency pulse repetition frequency can be tuned.

In the third step, a voltage source (pulse forming line) generates a pulse voltage, and the high-energy pulse cluster laser and the pulse voltage simultaneously act on the wide-bandgap semiconductor device. That is, the voltage source applies the voltage only when the high-energy pulse cluster laser starts to irradiate the semiconductor, and when the light irradiation ends, the voltage application also ends accordingly.

The high-energy pulsed cluster laser uses an optical waveguide or an optical fiber to irradiate the wide-bandgap semiconductor device from a hollow metal electrode to change the resistance of the wide-bandgap semiconductor device (here, the wide-bandgap photoconductive semiconductor device is essentially equivalent to a variable resistor, and its internal resistance According to the change of laser light intensity), the resistance of the wide-bandgap semiconductor device changes linearly with the light intensity of the high-energy pulsed cluster laser, the light intensity increases, and the resistance decreases.

At the same time, the wide-bandgap semiconductor device modulates the pulse voltage into a high-frequency electrical signal with the same frequency as the high-energy pulse cluster laser modulation frequency (the wide-bandgap semiconductor device works in a linear mode, that is, a photon incident into the device generates a pair of hole-electron pairs, and the electrons are in the It moves under the action of the electric field generated by the applied voltage, and then generates a current; the current generated by this mode has the same waveform and frequency as the incident laser; this working mode is based on Ohm's law "I=U/R", the pulse voltage U during the modulation process The resistance R changes inversely proportional to the light intensity, so the output current I of the wide-bandgap semiconductor device changes in direct proportion to the light intensity, so the periodically changing light intensity (ie, the high-energy pulse cluster laser) produces a periodically changing current, The two have the same frequency), and send the modulated high-frequency electrical signal to the radiation output component.

The fourth step, the radiation output component radiates the high frequency electrical signal: the radiation output component receives the high frequency electrical signal from the wide band gap semiconductor device, radiates the high frequency electrical signal, and generates the microwave signal output.

The light guide adaptive narrow-spectrum microwave generator constructed in the first step of the present invention has the characteristics of modularization, solid state and intelligence.

Compared with the traditional high-power microwave generation method based on pulsed power and relativistic vacuum tubes, the present invention has the following technical features:

1. The output microwave frequency is flexible - the parameters can be adjusted flexibly and flexibly, with the natural advantage of "intelligence". In the linear mode of the wide-bandgap semiconductor device of the present invention, an electron (carrier) is generated when a photon is incident into the SiC crystal, so the current in the SiC crystal is completely controlled by the high-energy pulsed cluster laser. With a recombination time of less than 1 ns, the semiconductor device can respond to an input optical signal of GHz and output an electrical signal of GHz. The electrical signal output by the wide-bandgap semiconductor device is consistent with the modulation frequency of the high-energy pulse cluster laser input to the device. The output frequency mainly depends on the modulation frequency of the high-energy pulse cluster laser, unlike the traditional high-power microwave device that only corresponds to one frequency point. In the present invention, by changing the modulation frequency of the high-energy pulse cluster laser (see step 2.7, the high-frequency signal source outputs a high-frequency sinusoidal signal with a frequency of the order of GHz flexibly adjustable; by adjusting the output frequency of the high-frequency signal source, the modulation frequency of the high-energy pulse cluster laser can be changed. Modulation frequency), which can realize the modulation of 10 times the microwave frequency, that is, adjustable from 0.1GHz to 1GHz, and the recombination time of SiC crystal carriers limits the upper limit of frequency modulation.

2. The microwave generated by the present invention has the capability of high repetition frequency—the repetition frequency of the present invention depends on the repetition frequency of the high-energy pulse cluster laser, and is only limited by the supply power of the equipment (such as armored vehicles, ships, and fighter jets) carrying the present invention . The repetition frequency of the existing electric vacuum scheme is only tens to 100 Hz, and the repetition frequency range of the high-energy pulse cluster laser of the present invention is 10 Hz to 200 kHz, so the present invention can realize a higher repetition frequency.

3. The light-guide adaptive narrow-spectrum microwave generator constructed in the first step of the present invention has high reliability—all units are solid-state, and the system does not require gas spark switches, vacuum electron beams and its ancillary equipment unlike traditional high-power microwave systems Therefore, the space utilization efficiency is high, the structure is compact and the volume is small, the reliability is higher, and the platform adaptability is stronger.

4. Stronger maneuverability - the light guide adaptive narrow-spectrum microwave generator produced in the first step of the present invention has the advantages of lighter weight and smaller volume. When it is mounted on the equipment, it can simultaneously allow the platform to add additional Energy storage system to enhance attack power.

5. The wide-bandgap semiconductor device in the present invention works in a linear mode, that is, a photon incident into the device generates a pair of hole-electron pairs, and the electrons move under the action of the electric field generated by the applied voltage, thereby generating current; The current and the incident laser have the same waveform and frequency. Therefore, the present invention can treat the photoconductive semiconductor as a "photoconductive amplifier" through high-frequency light regulation, and generate a narrow-spectrum microwave signal (when the pulse width of the microwave signal is 100ns, the spectrum width is on the order of 10MHz, or the relative bandwidth is on the order of 1%) , has better directional emission, and produces higher microwave energy.

6. In the present invention, the wide band gap semiconductor device is filled with the filling material, so as to avoid air flashover breakdown along the surface, improve the withstand voltage of the semiconductor device, and also improve the power capacity of the microwave generator.

The invention has broad application prospects in the fields of a new generation of high-power microwave technology, integrated detection and attack radar and cognitive electronic warfare.

Description of drawings

Fig. 1 is the overall flow chart of the present invention;

Fig. 2 is the logical structure diagram of the light guide adaptive narrow-spectrum microwave generator constructed in the first step of the present invention;

FIG. 3 is a schematic diagram of the overall structure of the high-energy pulsed cluster laser in FIG. 2 .

FIG. 4 is a schematic diagram of generating a preset waveform electrical signal. Among them, Fig. 4(a) is the envelope waveform of the input pulse cluster of the fiber amplifier 6, and 4(b) is the envelope waveform of the output pulse cluster of the fiber amplifier 6; Fig. 4(c) is the normalized target output rectangular envelope waveform; Fig. 4(d) is the normalized preset waveform;

5 is a structural diagram of a wide band gap semiconductor device;

FIG. 6 is a schematic diagram of the connection of the wide bandgap semiconductor device, the tripartite pulse forming line and the radiation component.

Detailed ways

Fig. 1 is the overall flow chart of the present invention; as shown in Fig. 1, the present invention comprises the following steps:

The first step is to build a light-guide adaptive narrow-spectrum microwave generator, as shown in Figure 2, the light-guide adaptive narrow-spectrum microwave generator consists of a circuit modulation module and an optical path modulation module. The optical path modulation module is a kind of microwave The high-energy pulse cluster laser of the signal source of the system photoconductive device, referred to as the high-energy pulse cluster laser for short, the circuit modulation module is composed of three parts: a voltage source 200 , a wide band gap semiconductor device 400 and a radiation output component 300 . The high-energy pulsed cluster laser is connected with the wide-bandgap semiconductor device 400 using an optical fiber or an optical waveguide.

High-energy pulse cluster lasers generate lasers with adjustable pulse cluster repetition frequency, pulse width, envelope waveform, and GHz high-frequency pulse repetition frequency, which are input into wide-bandgap semiconductor devices through optical fibers or optical waveguides.

As shown in Figure 3, the high-energy pulse cluster laser consists of a laser seed source 1, a fiber preamplifier 2, an optical modulation module 3, a high-frequency signal source 4, a synchronization control circuit 5, a fiber amplifier 6 and an editable waveform signal board 7. The laser seed source 1 , the fiber preamplifier 2 , the optical modulation module 3 and the fiber amplifier 6 are connected by fiber fusion. The high frequency signal source 4 , the synchronization control circuit 5 , the first editable waveform signal board 71 and the laser seed source 1 , the second editable waveform signal board 72 and the acousto-optic modulator 31 are connected by coaxial cables.

The optical modulation module 3 is composed of an acousto-optic modulator 31 and an electro-optical intensity modulator 32, and the acousto-optical modulator 31 and the electro-optical intensity modulator 32 are connected by means of a fiber splicing device pigtail. The output end of the laser seed source 1 and the input end of the fiber pre-amplifier 2, the output end of the fiber pre-amplifier 2 and the fiber input end of the optical modulation module 3 (that is, the fiber input end of the acousto-optic modulator 31), the output end of the optical modulation module 3 The output end (ie, the fiber output end of the electro-optical intensity modulator 32 ) and the input end of the fiber amplifier 6 are connected by fiber splicing, and the output end of the fiber amplifier 6 is fused with an end cap or isolator. And the signal input end of the laser seed source 6 is connected with the signal output end of the first editable waveform signal board 71 through a coaxial signal line; An output end is connected through a coaxial signal line; the external trigger signal input end of the second editable waveform signal board 71 is connected with the second output end of the synchronization control circuit 5 through a coaxial signal line, and the second editable waveform signal board 72 The signal output end is connected with the signal input end of the acousto-optic modulator 31 through a coaxial signal line. The radio frequency signal input end of the electro-optical intensity modulator 32 is connected with the signal output end of the high frequency signal source 4 by a coaxial signal line.

The synchronization control circuit 5 provides synchronization timing signals for the first editable waveform signal board 71 and the second editable waveform signal board 72 . The first synchronization timing signal output from the first output terminal of the synchronization control circuit 5 is used to trigger the first editable waveform signal board 71 , and the second synchronization timing signal output from the second output terminal is used to trigger the second editable waveform signal board 72 . It is required that the 2-way synchronous timing signal is a standard digital trigger signal with adjustable pulse width, adjustable repetition frequency, and an amplitude of 2.5V to 5V, and the time jitter between the first and second synchronous timing signal pulses is less than 5ns.

The first editable waveform signal board 71 is in the external trigger mode. When the first synchronization timing signal is received from the synchronization control circuit, the electrical pulse width is edited according to the requirements of the microwave system photoconductive device for the signal source pulse width, and the pulse width is sent to the laser seed. Source 1 sends a rectangular signal with adjustable repetition frequency and pulse width.

The laser seed source 1 adopts a semiconductor pulsed laser seed source, which can generate pulse repetition frequency, pulse width, amplitude, and time domain waveform according to the rectangular signal output by the first editable waveform signal board 71 flexibly. Tunable laser seed pulses. It is required that the center wavelength range of the semiconductor pulse laser seed source 1 is 1030nm～1065nm, the pulse width range is 10ns～200ns, and the repetition frequency range is 10Hz～200kHz.

The fiber preamplifier 2 increases the power of the laser seed pulse generated from the laser seed source, and improves the signal-to-noise ratio of the high-energy pulse cluster laser. The fiber preamplifier 2 is composed of M (M≥1) grade fiber amplifiers. It is required that the average power and peak power of the output laser pulse of the fiber pre-amplifier 2 be less than or equal to the maximum withstand power of the electro-optic intensity modulator.

The second editable waveform signal board 72 is in an external trigger operation mode, and sends a preset waveform electrical signal to the acousto-optic modulator when receiving the second synchronization timing signal from the synchronization control circuit 5 .

The acousto-optic modulator 31 is a fiber-coupled acousto-optic modulator with a bandwidth greater than 100MHz. On the one hand, the acousto-optic modulator 31 receives a preset waveform electrical signal from the second editable waveform signal board 72, modulates the optical pulse waveform output by the optical fiber preamplifier 2 into a preset time-domain waveform optical pulse, and modulates the preset time-domain waveform The optical pulses are sent to the electro-optical intensity modulator 32 ; on the other hand, the acousto-optical modulator 31 turns off the continuous spontaneous emission noise between the optical pulses output by the fiber preamplifier 2 .

The high-frequency signal source 4 is used to provide the electro-optical intensity modulator 32 with a high-frequency sinusoidal signal of the order of GHz with a flexible and adjustable frequency. The high-frequency signal source 4 can be any one of a voltage-controlled frequency-dependent oscillator, a frequency synthesizer, an arbitrary waveform generator, and a function generator, or can be a voltage-controlled frequency-dependent oscillator, a frequency synthesizer, an arbitrary waveform generator, Any combination of function generator and power amplifier. The voltage output by the high-frequency signal source 4 is required to be greater than the half-wave voltage of the electro-optical intensity modulator 32 .

The working bandwidth of the electro-optical intensity modulator 32 is greater than or equal to 10 GHz. The electro-optical intensity modulator 32 modulates the preset time-domain waveform light pulse received from the acousto-optic modulator 31 into a preset envelope waveform pulse cluster laser according to the high-frequency sinusoidal signal output by the high-frequency signal source, so that the preset envelope waveform The repetition frequency and waveform of the high frequency pulse in the pulse cluster laser are the same as the high frequency sinusoidal signal received from the high frequency signal source 1 , and the modulated pulse cluster laser is sent to the fiber amplifier 6 .

The optical fiber amplifier 6 amplifies the pulse cluster laser with preset envelope waveform received from the electro-optical intensity modulator, and outputs a rectangular envelope pulse cluster. The fiber amplifier 6 is composed of N (N≥2) grade fiber amplifiers. The output end of the fiber amplifier 6 is welded with a fiber end cap or an isolator to prevent damage to the high-energy pulse cluster laser caused by the return light from the end face.

As shown in FIG. 2 , the voltage source 200 is a solid-state pulse forming wire, and is connected to the electrode of the wide band gap semiconductor device 400 by conductive silver paste, so as to generate a pulse voltage and act on the wide band gap semiconductor device 400 .

The wide-bandgap semiconductor device 400 is connected to the high-energy pulsed cluster laser through an optical fiber or an optical waveguide, is connected to a voltage source through a conductive silver paste, and is connected to a radiation output component through a coaxial line. Under the simultaneous action of the laser and the voltage, a high-frequency electrical signal is generated , and output the high-frequency electrical signal to the radiation output component 300 .

As shown in FIG. 5 , the wide band gap semiconductor device 400 is composed of four parts: a semiconductor wafer 8 (ie, a substrate), two electrodes, a filling material 100 and a supporting structure 101. The combination of the semiconductor wafer 8 and the two electrodes is connected by a high-resistance semiconductor As the substrate material, a transparent conductive layer is prepared on the high-resistance semiconductor (the front side), a high-voltage passivation layer with anti-reflection effect is prepared on the transparent conductive layer, and then a metal ring is prepared to connect the transparent conductive layer (ie, high-voltage passivation There is a metal ring around the layer that is close to the transparent conductive layer), and then connected to the hollow metal electrode 91 (that is, the top of the metal ring is close to the hollow metal electrode 91); the back of the substrate is first prepared with a high-reflection silver-plated layer, and then Connected to solid metal electrode 92 . The hollow metal electrode 91 and the solid metal electrode 92 are the two electrodes in the present invention, and the rest (ie, the substrate material, the transparent conductive layer, the high-voltage passivation layer, the metal ring, and the silver-plated layer) are used in the present invention. 8 of the semiconductor wafers. The semiconductor wafer 8 can be a square sheet or a circular sheet, with a thickness of 0.01 mm to 10 mm, a side length of 1 mm to 50 mm when it is a square sheet, and a diameter of 1 mm to 50 mm when it is a circular sheet. The substrate material of the semiconductor wafer 8 is a wide-bandgap SiC material, such as 4H-SiC or 6H-SiC, the withstand voltage is required to be 3-4MV/cm, and the recombination time of SiC crystal carriers is less than 1ns. The material of the hollow metal electrode 91 and the solid metal electrode 92 can be stainless steel or brass; the ratio of the diameter of the hollow metal electrode 91 and the solid metal electrode 92 to the side length or diameter of the semiconductor wafer is maintained between 1 and 1.5; the hollow metal electrode 91 The connection with the solid metal electrode 92 and the semiconductor wafer is bonded by conductive silver glue, and the silver glue is cured after baking. The support structure 101 is a rectangular box without a lid made of PTFE material, the hollow metal electrode 91 passes through the first side 1011 of the support structure 101, one end is bonded to the first surface 81 of the semiconductor wafer 8, and the other end is connected to the voltage. The source is connected; one end of the solid metal electrode 92 is bonded to the second surface 82 of the semiconductor wafer 8 (a surface opposite to the first surface 81), and the other end passes through the second side 1012 of the support structure 101 and is connected to the voltage source; There is a filling material 100 between the semiconductor wafer 8, the hollow metal electrode 91, the solid metal electrode 92 and the support structure 101. The filling material 100 is required to completely cover the semiconductor wafer 8, the hollow metal electrode 91, and the solid metal electrode 92. The filling material 100 requires an average resistance. The field strength is greater than or equal to 40kV/mm, and when the light wavelength is 200nm to 1200nm, the transmittance of the light is greater than 99%, and the filling material is preferably epoxy resin.

As shown in Figure 6, the voltage source 200 is a solid state pulse forming wire. The withstand voltage range of the solid state pulse forming line is the same as that of the wide band gap semiconductor device 400 , and the impedance of the solid state pulse forming line is the same as the minimum on-state resistance of the wide band gap semiconductor device 400 under laser irradiation. The solid-state pulse forming line has a structure of three flat plates, which are stacked together according to the structure of metal plate-medium-metal plate-medium-metal plate. The medium is a dielectric material with high energy storage density (>1J/cm ³ ), and the metal plate material is silver. The connection between the voltage source 200 and the wide band gap semiconductor device 400 is as follows: the hollow metal electrode 91 and the solid metal electrode 92 of the wide band gap semiconductor device 400 are respectively connected to the middle metal plate 202 and the upper metal plate 201 of the voltage source 200, or the two electrodes are connected to the voltage source 200 Intermediate metal plate 202 and lower metal plate 203. (As shown in FIG. 6 , the two electrodes are connected to the middle metal plate 202 and the lower metal plate 203 of the voltage source 200 )

The radiation output component is a flat-panel broadband radiation horn 300 whose impedance is matched with the voltage source 200, and is connected to the wide-bandgap semiconductor device 400 through an SMA (SubMiniature version A) coaxial line, and radiates the high-frequency electrical signal output by the wide-bandgap semiconductor device 400. , produce microwave signal output.

In the second step, the high-energy pulsed cluster laser generates the high-energy pulsed cluster laser, and outputs the high-energy pulsed cluster laser to the wide-bandgap semiconductor device, the method is as follows:

2.1, the synchronous control circuit 5 outputs 2 digital signals with adjustable repetition frequency;

2.2. The first editable waveform signal board 71 is triggered by the first synchronization signal output by the synchronization control circuit 5, and the electrical pulses of the first editable waveform signal board 71 are edited according to the parameter requirements of the wide band gap semiconductor device 400 for the pulse width of the signal source Width, send a rectangular signal with adjustable pulse width to the laser seed source 1;

2.3, the laser seed source 1 receives the rectangular signal with adjustable pulse width output by the first editable waveform signal board 71, and generates a rectangular optical pulse with adjustable pulse width, and the repetition frequency and pulse width of this optical pulse can be adjusted;

2.4. The fiber pre-amplifier 2 amplifies the energy of the rectangular light pulse output by the laser seed source 1 to not exceed the maximum withstand power of the electro-optical intensity modulator 32 to improve the signal-to-noise ratio. The output laser pulse waveform is characterized by the gain saturation effect. distorted;

2.5. The second editable waveform signal board 72 is triggered by the synchronization control circuit outputting the second synchronization signal, and outputs a rectangular electrical signal with the same pulse width as the first editable waveform signal board 71 .

2.6, the acousto-optic modulator 31 receives a rectangular electrical signal with the same pulse width as the first editable waveform signal board 71 from the second editable waveform signal board 72, that is, the laser pulse waveform output by the fiber preamplifier 2 is not changed, and the Sending the laser pulses of changing time-domain waveforms to the electro-optical intensity modulator 32;

2.7, the high-frequency signal source 4 outputs a high-frequency sinusoidal signal with a flexible and adjustable frequency of the order of GHz;

2.8. The electro-optical intensity modulator 32 modulates the laser pulse of the unchanged time-domain waveform received from the acousto-optic modulator 31 into a pulse-cluster laser with the same envelope waveform according to the high-frequency sinusoidal signal received from the high-frequency signal source 4, so that the pulse The repetition frequency and waveform of the high-frequency pulses in the cluster are the same as the high-frequency sinusoidal signals received from the high-frequency signal source 4, and the pulsed cluster laser is sent to the fiber amplifier 6;

2.9, test the input pulse cluster laser envelope waveform, output pulse cluster laser envelope waveform and pulse cluster laser energy of the fiber amplifier 6, and calculate the time duration from the pulse cluster energy, the input pulse cluster envelope waveform, and the output pulse cluster envelope waveform. Input pulse cluster instantaneous power P _in (t and time-dependent output pulse cluster instantaneous power P _out (t), import the Matlab program to extract the envelope waveform, as the initial input and output waveform, calculate the time-dependent gain curve, by the formula (1) The initial gain G ₀ and the saturated energy flow E _sat parameter of the amplifier are obtained by curve fitting. Then the rectangular envelope waveform is set as the target output envelope waveform, and the Matlab program (including the stochastic parallel gradient descent algorithm) is run to obtain the preset waveform electrical signal;

As shown in Figure 4, the preset waveform electrical signal is obtained by the following method:

2.9.1. Set the output signal of the second editable waveform signal board 72 to a rectangle, that is, the output signal of the second editable waveform signal board 72 makes the acousto-optic modulator 31 not change the laser pulse waveform output by the fiber preamplifier 2 . Under this condition, use a high-speed oscilloscope, a photodetector and a power meter to test the input burst envelope waveform, output burst envelope waveform and burst energy of the fiber amplifier 6. The pulse cluster envelope waveform is calculated to obtain the time-dependent input pulse cluster instantaneous power P _in (t) and the time-dependent output pulse cluster instantaneous power P _out (t).

2.9.2. Import the obtained time-dependent input pulse cluster instantaneous power P _in (t) and time-dependent output pulse cluster instantaneous power P _out (t) into the Matlab program (including stochastic parallel gradient descent optimization algorithm), and extract the envelope waveform , as the initial input and output waveforms when the stochastic parallel gradient descent algorithm calculates the pre-compensated waveform, as shown in Fig. 4(a) Fiber amplifier 6 input pulse cluster envelope waveform, the ordinate is the instantaneous power, the unit is watt, and the abscissa is the time , the unit is nanoseconds, Figure 4(b) is the envelope waveform of the output pulse cluster of the fiber amplifier 6, the ordinate is the instantaneous power, because the power is amplified by the fiber amplifier 6, the unit is kilowatts, the abscissa is the time, the unit is nanoseconds .

2.9.3, the time-dependent gain function G(t) is calculated by the formula G(t)=P _out (t)/P _in (t). According to the gain formula (1) in the amplifier FN model,

G(t)=1+(G ₀ -1)exp[-E _out (t)/E _sat ] (1)

Curve fitting obtains the initial gain G ₀ and the saturation energy flow E _sat parameter of the amplifier;

2.9.4. Set the rectangular envelope waveform as the target output envelope waveform of the Matlab program, and the normalized target output rectangular envelope waveform is shown in Figure 4(c). In Figure 4(c), the ordinate is normalized value, the abscissa is time, the unit is nanosecond;

2.9.5, run the MATLAB program to get the preset waveform. The normalized preset waveform is shown in Figure 4(d). In Figure 4(d), the ordinate is the normalized value, the abscissa is the time, and the unit is nano second.

2.10. Edit the output pulse waveform of the second editable waveform signal board 72 according to the preset waveform electrical signal, so that the second editable waveform signal board 72 outputs the preset waveform electrical signal to the acousto-optic modulator 31 .

2.11, the acousto-optic modulator 31 receives a preset waveform electrical signal from the second editable waveform signal board 27, and modulates the optical pulse waveform output by the optical fiber preamplifier 2 into a preset time-domain waveform optical pulse, which is characterized in that the waveform is after the above The preset waveform calculated in the steps can make the pulse cluster envelope waveform output by the fiber amplifier 6 be rectangular, and send the preset time-domain waveform optical pulse to the electro-optical intensity modulator 32 .

2.12, the electro-optical intensity modulator 32 modulates the preset time-domain waveform light pulse received from the acousto-optic modulator 31 into a preset envelope waveform pulse cluster laser according to the high-frequency sinusoidal signal received from the high-frequency signal source 4, which is characterized by: The pulse cluster is in the form of a pulse cluster, and the pulse cluster envelope is a preset waveform, so that the repetition frequency and waveform of the high-frequency pulse in the pulse cluster laser of the preset envelope waveform are the same as the high-frequency sinusoidal signal received from the high-frequency signal source 4, and the modulation The resulting pulse cluster laser is sent to the fiber amplifier 6;

2.13, the fiber amplifier 6 amplifies the preset envelope waveform pulse cluster laser received from the electro-optical intensity modulator 32, and outputs a high-energy pulse cluster laser to the wide-bandgap semiconductor device. The pulse cluster laser repetition frequency, pulse width, envelope waveform, GHz high frequency, pulse repetition frequency can be tuned.

In the third step, the voltage source 200 (ie, the pulse forming line) generates a pulse voltage, and the high-energy pulse cluster laser and the pulse voltage simultaneously act on the wide-bandgap semiconductor device 400 . That is, the voltage source only applies the voltage when the high-energy pulsed cluster laser starts to irradiate the semiconductor, and when the light finishes irradiating, the voltage application also ends accordingly.

The high-energy pulsed cluster laser uses an optical waveguide or an optical fiber to irradiate the wide-bandgap semiconductor device 400 from the hollow metal electrode 91 to change the resistance of the wide-bandgap semiconductor device 400. The resistance of the wide-bandgap semiconductor device 400 varies with the light intensity of the high-energy pulsed cluster laser. Linear change, the light intensity increases and the resistance decreases.

At the same time, the wide bandgap semiconductor device 400 modulates the pulse voltage into a high-frequency electrical signal with the same modulation frequency as the high-energy pulse cluster laser, and sends the modulated high-frequency electrical signal to the radiation output component.

The fourth step, the radiation output component radiates high-frequency electrical signals: the radiation output component receives high-frequency electrical signals from the wide-bandgap semiconductor, radiates the high-frequency electrical signals, and generates microwave signal output.

Claims (16)

1. a light-guide adaptive narrow-spectrum microwave generation method based on high-energy pulsed cluster laser is characterized in that comprising the following steps: The first step is to build a light-guide adaptive narrow-spectrum microwave generator. The light-guide adaptive narrow-spectrum microwave generator consists of a circuit modulation module and an optical path modulation module. The optical path modulation module is a high-energy pulse cluster laser, and the circuit modulation module is composed of a voltage source. (200), a wide band gap semiconductor device (400) and a radiation output assembly (300) are composed of three parts, the high-energy pulse cluster laser and the wide band gap semiconductor device (400) are connected by an optical fiber or an optical waveguide; The high-energy pulse cluster laser generates laser with adjustable pulse cluster repetition frequency, pulse width, envelope waveform, and GHz high-frequency pulse repetition frequency, and is input into the wide-bandgap semiconductor device (400) through an optical fiber or an optical waveguide; The high-energy pulse cluster laser consists of a laser seed source (1), a fiber preamplifier (2), an optical modulation module (3), a high-frequency signal source (4), a synchronous control circuit (5), a fiber amplifier (6), and two The editing waveform signal board (7) is composed of a first editable waveform signal board (71) and a second editable waveform signal board (72); the optical modulation module (3) is composed of an acousto-optic modulator (31) and an electro-optical intensity modulator (32) composition, the acousto-optic modulator (31) and the electro-optic intensity modulator (32) are connected in the way of fiber splicing device pigtail; the output end of the laser seed source (1) is connected with the input end of the fiber pre-amplifier (2), The output end of the optical fiber preamplifier (2) and the optical fiber input end of the optical modulation module (3) are the optical fiber input end of the acousto-optic modulator (31), and the output end of the optical modulation module (3) is the electro-optical intensity modulator (32) The output end of the optical fiber and the input end of the fiber amplifier (6) are connected by fiber fusion; the signal input end of the laser seed source (1) and the signal output end of the first editable waveform signal board (71) are connected by a coaxial signal the external trigger signal input end of the first editable waveform signal board (71) is connected with the first output end of the synchronization control circuit (5) through a coaxial signal line; the external trigger signal of the second editable waveform signal board (72) The trigger signal input end is connected with the second output end of the synchronization control circuit (5) through a coaxial signal line, and the signal output end of the second editable waveform signal board (72) is connected with the signal input end of the acousto-optic modulator (31) through The coaxial signal line is connected, and the radio frequency signal input end of the electro-optical intensity modulator (32) is connected with the signal output end of the high frequency signal source (4) by a coaxial signal line; The synchronization control circuit (5) provides a synchronization timing signal for the first editable waveform signal board (71) and the second editable waveform signal board (72); the first synchronization timing signal output from the first output end is used to trigger the first editable waveform signal board (72). an editing waveform signal board (71), and the second synchronous timing signal output from the second output terminal is used to trigger the second editable waveform signal board (72); The first editable waveform signal board (71) is in an external trigger operation mode. When receiving the first synchronization timing signal from the synchronization control circuit (5), the electric pulse width is edited according to the requirements of the microwave system photoconductive device for the pulse width of the signal source, Send a rectangular signal with adjustable repetition frequency and pulse width to the laser seed source (1); The laser seed source (1) adopts a semiconductor pulsed laser seed source, and generates laser seed pulses with flexible and adjustable pulse repetition frequency, pulse width, amplitude and time domain waveform according to the rectangular signal output by the first editable waveform signal board (71). ; The fiber preamplifier (2) increases the power of the laser seed pulse generated from the laser seed source (1), and improves the signal-to-noise ratio of the high-energy pulse cluster laser as the signal source of the photoconductive device of the microwave system; the fiber preamplifier (2) is composed of M It is composed of grade fiber amplifier, M≥1; The second editable waveform signal board (72) is in an external trigger operation mode, and sends a preset waveform electrical signal to the acousto-optic modulator (31) when receiving the second synchronization timing signal from the synchronization control circuit (5); The acousto-optic modulator (31) is a fiber-coupled acousto-optic modulator, and the acousto-optic modulator (31) receives a preset waveform electrical signal from the second editable waveform signal board (72) on the one hand, and outputs the fiber preamplifier (2) The optical pulse waveform is modulated into a preset time-domain waveform optical pulse, and the preset time-domain waveform optical pulse is sent to the electro-optical intensity modulator (32); on the other hand, the acousto-optical modulator (31) turns off the fiber preamplifier (2). ) continuous spontaneous emission noise between the output optical pulses; The high-frequency signal source (4) is used to provide the electro-optical intensity modulator (32) with a frequency-adjustable GHz-level high-frequency sinusoidal signal, and the output voltage of the high-frequency signal source (4) is required to be greater than the voltage of the electro-optical intensity modulator (32). half-wave voltage; The electro-optical intensity modulator (32) modulates the preset time-domain waveform light pulse received from the acousto-optical modulator (31) into a preset envelope waveform pulse cluster laser according to the high-frequency sinusoidal signal output by the high-frequency signal source (4) , so that the repetition frequency and waveform of the high-frequency pulses in the pulse-cluster laser with the preset envelope waveform are the same as the high-frequency sinusoidal signal received from the high-frequency signal source (4), and the modulated pulse-cluster laser is sent to the fiber amplifier (6). ); The fiber amplifier (6) amplifies the preset envelope waveform pulse cluster laser light received from the electro-optical intensity modulator (32), and outputs a rectangular envelope pulse cluster, and the fiber amplifier (6) is composed of N-level fiber amplifiers, N≥2; The output end of the optical fiber amplifier (6) is welded with an optical fiber end cap or an isolator; The wide-bandgap semiconductor device (400) is connected to a high-energy pulse cluster laser through an optical fiber or an optical waveguide, is connected to a voltage source (200) through a conductive silver paste, and is connected to a radiation output component through a coaxial line. Under the simultaneous action of the laser and the voltage, A high-frequency electrical signal is generated, and the high-frequency electrical signal is output to the radiation output component; the wide-bandgap semiconductor device (400) is composed of a semiconductor wafer (8), a hollow metal electrode (91), a solid metal electrode (92), and a filling material (100). ) and a supporting structure (101); The voltage source (200) is a solid-state pulse forming wire, and is connected with the electrode of the wide-bandgap semiconductor device (400) by conductive silver paste, so as to generate a pulse voltage and act on the wide-bandgap semiconductor device (400); The radiation output component (300) is a flat-plate broadband radiation horn whose impedance is matched with the voltage source (200), and is connected to the wide-bandgap semiconductor device (400) through an SMA coaxial line; In the second step, the high-energy pulsed cluster laser generates the high-energy pulsed cluster laser, and outputs the high-energy pulsed cluster laser to the wide band gap semiconductor device (400), the method is as follows: 2.1, the synchronous control circuit (5) outputs 2 digital signals with adjustable repetition frequency; 2.2. The first editable waveform signal board (71) is triggered by the first synchronization signal output by the synchronization control circuit (5), and the first editable waveform is edited according to the parameter requirements of the wide band gap semiconductor device (400) for the pulse width of the signal source The electrical pulse width of the signal board (71) sends a rectangular signal with adjustable pulse width to the laser seed source (1); 2.3, the laser seed source (1) receives a rectangular signal with adjustable pulse width output by the first editable waveform signal board (71), and generates a rectangular light pulse with adjustable pulse width; 2.4, the optical fiber pre-amplifier (2) amplifies the energy of the rectangular light pulse output by the laser seed source (1) to not exceed the maximum withstand power of the electro-optical intensity modulator (32), so as to improve the signal-to-noise ratio; 2.5, the second editable waveform signal board (72) is triggered by the synchronization control circuit outputting the second synchronous signal, and outputs a rectangular electrical signal with the same pulse width as the first editable waveform signal board (71); 2.6, the acousto-optic modulator (31) receives a rectangular electrical signal with the same pulse width as the first editable waveform signal board (71) from the second editable waveform signal board (72), that is, the output of the optical fiber preamplifier (2) is not changed The laser pulse waveform is obtained, and the laser pulse without changing the time domain waveform is sent to the electro-optical intensity modulator (32); 2.7. The high-frequency signal source (4) outputs a high-frequency sinusoidal signal with a flexible and adjustable frequency of the order of GHz; 2.8, the electro-optical intensity modulator (32) modulates the laser pulse of the unchanged time-domain waveform received from the acousto-optical modulator (31) into a laser pulse of the same envelope waveform according to the high-frequency sinusoidal signal received from the high-frequency signal source (4). pulse cluster laser, so that the repetition frequency and waveform of the high frequency pulse in the pulse cluster are the same as the high frequency sinusoidal signal received from the high frequency signal source (4), and send the pulse cluster laser to the fiber amplifier (6); 2.9, test the input pulse cluster laser envelope waveform, the output pulse cluster laser envelope waveform and the pulse cluster laser energy E _out (t) of the fiber amplifier (6). The envelope waveform is calculated to obtain the time-dependent input pulse cluster instantaneous power P _in (t) and the time-dependent output pulse cluster instantaneous power P _out (t), t is the time, import the Matlab program containing the stochastic parallel gradient descent algorithm to extract the packet. As the initial input and output waveform, the time-dependent gain curve is calculated, and the initial gain G ₀ and the saturated energy flow E _sat parameter of the amplifier are obtained by curve fitting, and then the rectangular envelope waveform is set as the target output envelope waveform , run the Matlab program to get the preset waveform electrical signal; 2.10. Edit the output pulse waveform of the second editable waveform signal board (72) according to the preset waveform electrical signal, so that the second editable waveform signal board (72) outputs the preset waveform electrical signal to the acousto-optic modulator (31). ; 2.11, the acousto-optic modulator (31) receives a preset waveform electrical signal from the second editable waveform signal board 27, modulates the optical pulse waveform output by the optical fiber preamplifier (2) into a preset time-domain waveform optical pulse, and modulates the pre- Set the time-domain waveform light pulse to be sent to the electro-optical intensity modulator (32); 2.12, the electro-optical intensity modulator (32) modulates the preset time-domain waveform optical pulse received from the acousto-optical modulator (31) into a preset envelope waveform pulse according to the high-frequency sinusoidal signal received from the high-frequency signal source (4) Cluster laser, preset envelope waveform The pulse cluster laser is in the form of a pulse cluster, and the pulse cluster envelope is a preset waveform, so that the repetition frequency and waveform of the high-frequency pulses in the pulse cluster laser with the preset envelope waveform are the same as those from the high-frequency signal source. (4) The received high-frequency sinusoidal signals are the same, and the modulated pulse cluster laser is sent to the fiber amplifier (6); 2.13, the fiber amplifier (6) amplifies the pulse-cluster laser light with the preset envelope waveform received from the electro-optical intensity modulator (32), and outputs the high-energy pulse-cluster laser light to the wide-bandgap semiconductor device (400). Pulse width, envelope waveform, GHz high frequency, and pulse repetition frequency can be tuned; In the third step, the voltage source (200) generates a pulsed voltage, and the high-energy pulsed cluster laser and the pulsed voltage simultaneously act on the wide-bandgap semiconductor device (400); the high-energy pulsed cluster laser uses an optical waveguide or an optical fiber to irradiate the hollow metal electrode (91) To the wide band gap semiconductor device (400), changing the resistance of the wide band gap semiconductor device (400), the resistance of the wide band gap semiconductor device (400) changes linearly with the light intensity of the high-energy pulse cluster laser, the light intensity increases, and the resistance decreases At the same time, the wide-bandgap semiconductor device (400) modulates the pulse voltage into a high-frequency electrical signal with the same modulation frequency as the high-energy pulse cluster laser, and sends the modulated high-frequency electrical signal to the radiation output component (300); The fourth step, the radiation output component (300) radiates the high frequency electrical signal: the radiation output component (300) receives the high frequency electrical signal from the wide band gap semiconductor device (400), radiates the high frequency electrical signal, and generates a microwave signal output. 2. A kind of light-guide adaptive narrow-spectrum microwave generation method based on high-energy pulse cluster laser as claimed in claim 1, it is characterized in that the first synchronization timing signal and the second synchronization timing signal output by the synchronization control circuit (5) It is a standard digital trigger signal with adjustable pulse width, adjustable repetition frequency and amplitude of 2.5V to 5V, and the time jitter between the pulses of the first synchronization timing signal and the second synchronization timing signal is less than 5ns. 3 . The light-guide adaptive narrow-spectrum microwave generation method based on a high-energy pulse cluster laser according to claim 1 , wherein the central wavelength range of the laser seed source (1) is 1030 nm to 1065 nm, and the pulse width range is 3 . 10ns～200ns, repetition frequency range is 10Hz～200kHz. 4. A kind of light-guide adaptive narrow-spectrum microwave generation method based on high-energy pulse cluster laser as claimed in claim 1, it is characterized in that the average power and peak power of output laser pulse of described fiber pre-amplifier (2) are less than or equal to electro-optical intensity Maximum withstand power of the modulator (32). 5. The light-guide adaptive narrow-spectrum microwave generation method based on high-energy pulse cluster laser according to claim 1, characterized in that the bandwidth of the acousto-optic modulator (31) is greater than 100 MHz, and the electro-optical intensity modulator (32) ) operating bandwidth is greater than or equal to 10GHz. 6. The light-guide adaptive narrow-spectrum microwave generation method based on high-energy pulse cluster laser as claimed in claim 1, wherein the high-frequency signal source (4) is a voltage-controlled frequency-dependent oscillator, a frequency synthesizer, Any one of arbitrary waveform generator and function generator, or a combination of any one of VCO, frequency synthesizer, arbitrary waveform generator, function generator and power amplifier. 7. The light-guide adaptive narrow-spectrum microwave generation method based on high-energy pulse cluster laser as claimed in claim 1, characterized in that the semiconductor wafer (8) of the wide-bandgap semiconductor device (400) is connected to two electrodes, The semiconductor wafer (8) is composed of a substrate material, a transparent conductive layer, a high-voltage resistant passivation layer, a metal ring, and a silver-plated layer; the substrate material is a high-resistance semiconductor, and a transparent conductive layer is prepared on the front of the high-resistance semiconductor, and the transparent conductive layer is formed on the front of the high-resistance semiconductor. A high-voltage resistant passivation layer is prepared on the layer, a metal ring around the high-voltage resistant passivation layer is in close contact with the transparent conductive layer, and the top of the metal ring is in close contact with a hollow metal electrode (91); a silver-plated layer is prepared on the back of the high resistance semiconductor, It is connected with the solid metal electrode (92); the support structure (101) is a rectangular box without a cover which is made of polytetrafluoroethylene material, and the hollow metal electrode (91) passes through the first side surface 1011 of the support structure (101), and one end is connected to the The first surface 81 of the semiconductor wafer (8) is bonded, and the other end is connected to a voltage source (200); one end of the solid metal electrode (92) is bonded to the second surface 82 of the semiconductor wafer (8), and the other end passes through the support Second side 1012 of structure (101), connected to voltage source (200); filling material (100) between semiconductor wafer (8), hollow metal electrode (91), solid metal electrode (92) and support structure (101) ), the filling material (100) is required to completely cover the semiconductor wafer (8), the hollow metal electrode (91), and the solid metal electrode (92). 8. A method for generating light-guided adaptive narrow-spectrum microwaves based on high-energy pulse cluster laser according to claim 7, characterized in that the semiconductor wafer (8) of the wide-bandgap semiconductor device (400) is a square sheet or a circular shape The sheet has a thickness of 0.01 mm to 10 mm, a side length of 1 mm to 50 mm when it is a square sheet, and a diameter of 1 mm to 50 mm when it is a circular sheet. 9. The light-guide adaptive narrow-spectrum microwave generation method based on high-energy pulsed cluster laser according to claim 7, wherein the high-resistance semiconductor of the wide-bandgap semiconductor device (400) selects wide-bandgap SiC material, and has a withstand voltage The requirement is 3～4MV/cm, and the recombination time of SiC crystal carriers is less than 1ns. 10 . The light-guide adaptive narrow-spectrum microwave generation method based on high-energy pulsed cluster laser according to claim 9 , wherein the SiC material refers to 4H-SiC or 6H-SiC material. 11 . 11. The light-guide adaptive narrow-spectrum microwave generation method based on high-energy pulse cluster laser according to claim 7, characterized in that the hollow metal electrode (91) and the solid metal electrode ( 92) The material is stainless steel or brass; the ratio of the diameter of the hollow metal electrode (91) and the solid metal electrode (92) to the side length or diameter of the semiconductor wafer (8) is maintained between 1 and 1.5; the hollow metal electrode (91) ) and the solid metal electrode (92) and the semiconductor wafer (8) are connected by conductive silver paste. 12. The light-guide adaptive narrow-spectrum microwave generation method based on high-energy pulse cluster laser according to claim 7, characterized in that the filling material (100) of the wide-bandgap semiconductor device (400) requires an average withstand voltage≥40kV /mm, when the wavelength of light is 200nm to 1200nm, the transmittance of light is greater than 99%. 13 . The light-guide adaptive narrow-spectrum microwave generation method based on high-energy pulse cluster laser according to claim 12 , wherein the filling material is epoxy resin. 14 . 14. A light-guide adaptive narrow-spectrum microwave generation method based on high-energy pulse cluster laser according to claim 1, characterized in that the withstand voltage range of the solid-state pulse forming line and the withstand voltage of the wide-bandgap semiconductor device (400) The range is the same, and the solid-state pulse-forming line impedance is the same as the on-state minimum resistance of the wide-bandgap semiconductor device (400) under laser irradiation. 15. The light-guide adaptive narrow-spectrum microwave generation method based on high-energy pulse cluster laser as claimed in claim 1, wherein the solid-state pulse forming line is a three-plate structure, according to metal plate-medium-metal plate-medium - The structure of the metal plates is stacked together; the medium is a dielectric material with energy storage density >1J/cm ³ , and the metal plate material is silver; the connection method of the voltage source (200) and the wide-bandgap semiconductor device (400) is: wideband The hollow metal electrode (91) and the solid metal electrode (92) of the gap semiconductor device (400) are respectively connected to the middle metal plate 202 and the upper metal plate 201 of the voltage source (200), or the hollow metal electrode (91) and the solid metal electrode ( 92) Connect the middle metal plate 202 and the lower metal plate 203 of the voltage source (200). 16. The light-guide adaptive narrow-spectrum microwave generation method based on high-energy pulse cluster laser according to claim 1, characterized in that the preset waveform electrical signal of the second editable waveform signal board (72) in step 2.9 adopts the The following method is obtained: 2.9.1, set the output signal of the second editable waveform signal board (72) as a rectangle, and use a high-speed oscilloscope, a photodetector and a power meter to test the input pulse cluster envelope waveform of the fiber amplifier (6) under this condition, The output pulse cluster envelope waveform and pulse cluster energy are calculated from the pulse cluster energy, the input pulse cluster envelope waveform, and the output pulse cluster envelope waveform to obtain the time-dependent input pulse cluster instantaneous power P _in (t) and the time-dependent output pulse cluster instantaneous power P in (t) power P _out (t); 2.9.2, import P _in (t) and P _out (t) into the Matlab program containing the stochastic parallel gradient descent optimization algorithm, extract the envelope waveform, and use it as the initial input and output waveform; 2.9.3, the time-dependent gain function G(t) is calculated by the formula G(t)=P _out (t)/P _in (t). According to the gain formula (1) in the amplifier FN model, G(t)=1+(G ₀ -1)exp[-E _out (t)/E _sat ] (1) Curve fitting obtains the initial gain G ₀ and the saturation energy flow E _sat parameter of the amplifier; 2.9.4, set the rectangular envelope waveform as the target output envelope waveform of the Matlab program; 2.9.5, run the MATLAB program to obtain the preset waveform electrical signal.

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