Array reconfigurable YIG magneto-static wave excitation system

Abstract

The application discloses an array reconfigurable YIG static magnetic wave excitation system, and belongs to the field of microwave devices and magnetism. The static magnetic wave excitation system comprises a YIG film, an input array transducer, an input adjustable phase shifter group, a power distribution network, an input control unit, an output array transducer, an output adjustable phase shifter group, a power synthesis network, an output control unit, a mixer, an analog-to-digital conversion and an FPGA. The application can accurately excite the static magnetic wave according to a preset target frequency and a target wave number, and realizes open-loop control. Compared with a traditional bias magnetic field adjusting method, the application can directly complete excitation of a corresponding frequency static magnetic wave through system setting, instead of matching a target excitation frequency through multiple bias magnetic field parameter adjustments, so that the operation process is obviously simplified and the excitation accuracy is improved.

Description

Technical Field

[0001] This invention belongs to the field of microwave devices and magnetism, specifically relating to an array-reconfigurable YIG static magnetic wave excitation system. Background Technology

[0002] Yttrium iron garnet (YIG), a typical microwave gyromagnetic material, can generate magnetostatic waves within its surface by generating an alternating magnetic field through its surface transducer. Since the propagation speed of magnetostatic waves is much lower than that of electromagnetic waves, this characteristic makes YIG naturally suitable for radio frequency (RF) delay lines, enabling signal time delay. Furthermore, since magnetostatic waves only propagate effectively within a limited frequency band, YIG-based devices can also be used as bandpass filters. When the magnetic field strength in YIG exceeds a certain critical threshold, it triggers unstable growth of the half-frequency spin wave, causing the energy of the uniform precession to transfer to the half-frequency spin wave, thereby effectively limiting the uniform precession amplitude and achieving a limiting protection function. Therefore, a single YIG device, in principle, possesses multiple RF processing capabilities, including delay, filtering, and limiting.

[0003] The actual operating frequency band of the aforementioned functions depends on the intensity and spectral distribution of the excited magnetostatic wave, both of which are determined by the radiation resistance of the device. Currently, the radiation resistance mainly relies on the geometry of the surface transducer and is adjusted by changing the intensity of the applied magnetic field. By changing the coil current to adjust the magnetic field, frequency tuning can be achieved over a wide range, making multi-band applications of YIG devices possible. However, this control method has two inherent limitations: first, the magnetic field is generated by a energized coil, and tuning requires changing the current; however, the coil inductance causes the current change to be slow, resulting in an extremely slow magnetic field response, making it difficult to meet the requirements of rapid frequency hopping or real-time dynamic tuning; second, limited by the transducer's excitation mechanism, this type of device can only excite low-wavenumber magnetostatic waves, and cannot achieve flexible excitation of arbitrary wavenumbers, severely restricting the design freedom and application scope of the device. These shortcomings make it difficult for existing YIG magnetostatic wave devices to be widely promoted and applied in practical radio frequency systems. Summary of the Invention

[0004] The purpose of this invention is to address the problems existing in the background technology by proposing an array-reconfigurable YIG static magnetic wave excitation system.

[0005] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0006] An array-reconfigurable YIG magnetostatic wave excitation system includes a YIG thin film, an input array transducer, an input adjustable phase shifter group, a power distribution network, an input control unit, an output array transducer, an output adjustable phase shifter group, a power combining network, an output control unit, a mixer, an analog-to-digital converter, and an FPGA;

[0007] The input array transducer is disposed on the surface of the YIG thin film and includes N parallel input unit transducers, where N is a positive integer ≥ 2; the output array transducer is disposed on the surface of the YIG thin film and includes M parallel output unit transducers, where M is a positive integer ≥ 2; the input adjustable phase shifter group includes N input unit adjustable phase shifters, and the output adjustable phase shifter group includes M output unit adjustable phase shifters;

[0008] One end of each of the N input unit transducers is grounded, and the other end is connected to the output of each of the N input unit adjustable phase shifters. The inputs of the N input unit adjustable phase shifters are connected to the same power distribution network, and the input of the power distribution network serves as the input of the excitation system. The input control unit is connected to the N input unit adjustable phase shifters and is used to control the additional phase value of each input unit adjustable phase shifter.

[0009] One end of each of the M output unit transducers is grounded, and the other end is connected to the input of each of the M output unit adjustable phase shifters. The outputs of the M output unit adjustable phase shifters are connected to the same power combining network, and the output of the power combining network serves as the output of the excitation system. The output control unit is connected to the M output unit adjustable phase shifters and is used to control the additional phase value of each output unit adjustable phase shifter.

[0010] The two inputs of the mixer are connected to the power distribution network and the power combining network, respectively. The output of the mixer is connected to the analog-to-digital converter, and the output of the analog-to-digital converter is connected to the FPGA. The FPGA is connected to the input control unit and the output control unit.

[0011] Furthermore, the N input unit transducers in the input array transducer have equal widths and the spacing between adjacent input unit transducers is equal; the M output unit transducers in the output array transducer have equal widths and the spacing between adjacent output unit transducers is equal.

[0012] Preferably, the input unit transducer is parallel to the output unit transducer.

[0013] Furthermore, the phase difference value of the phase shifter between two adjacent input units is adjustable. Constant. That is, assuming the additional phase of the adjustable phase shifter of the first input unit is 0, then the additional phase of the adjustable phase shifter of the second input unit is... The additional phase of the adjustable phase shifter in the third input unit is The additional phase of the adjustable phase shifter of the Nth input unit is... Assume the additional phase of the adjustable phase shifter in the first input unit is... The additional phase of the adjustable phase shifter in the second input unit is The additional phase of the adjustable phase shifter in the third input unit is The additional phase of the adjustable phase shifter of the Nth input unit is... .

[0014] Furthermore, the phase difference value of the adjustable phase shifter between two adjacent output units Constant. That is, assuming the additional phase of the adjustable phase shifter of the first output unit is 0, then the additional phase of the adjustable phase shifter of the second output unit is... The additional phase of the adjustable phase shifter in the third output unit is The additional phase of the adjustable phase shifter of the Mth output unit is... Assume the additional phase of the adjustable phase shifter in the first output unit is... The additional phase of the adjustable phase shifter in the second output unit is The additional phase of the adjustable phase shifter in the third output unit is The additional phase of the adjustable phase shifter of the Mth output unit is... .

[0015] Furthermore, the phase difference value of the adjustable phase shifter between two adjacent output units Phase difference between the adjustable phase shifters of the two adjacent input units They can be the same or different.

[0016] Furthermore, the magnetostatic wave excitation system is in a bias magnetic field environment, and the direction of the magnetic field is consistent with the direction of the input unit transducer or the output unit transducer, or perpendicular to the direction of the input unit transducer or the output unit transducer in the YIG thin film plane, or perpendicular to the YIG thin film surface, so as to excite magnetostatic surface waves, magnetostatic backward body waves and magnetostatic forward body waves.

[0017] Furthermore, the two inputs of the mixer are connected to the power distribution network and the power combining network, respectively. The mixer mixes the two signals to an intermediate frequency (IF), which is then converted from analog to digital by the analog-to-digital converter (ADC) unit before being connected to the input of the FPGA. The output of the FPGA is connected to the input control unit and the output control unit. The FPGA can receive the output of the ADC for closed-loop control, or it can operate without receiving the ADC output for open-loop control.

[0018] Furthermore, when the FPGA does not receive the output of the analog-to-digital converter, i.e., when the magnetostatic wave excitation system is used in open loop, the FPGA controls the phase difference between the adjustable phase shifters of two adjacent input units. Phase difference between the adjustable phase shifters of the two adjacent output units All To stimulate the wave number specified by the user , For the specified wave number, This refers to the spacing between two adjacent transducer units in the input or output array transducer. Alternatively, it can be minimized first using a gradient descent algorithm. Obtain the user-specified desired frequency. The corresponding wave number Then set the phase difference value between the adjustable phase shifters of two adjacent input units. Phase difference between the adjustable phase shifters of the two adjacent output units All To stimulate the desired frequency. Among them Represents the L2 norm, The dispersion relation in YIG thin films varies with different YIG film configurations; however, this invention does not impose a specific limitation on it. For the specified desired frequency, The interval between two adjacent unit transducers of the input or output array transducer.

[0019] Furthermore, when the FPGA receives the output of the analog-to-digital conversion, i.e., when the magnetostatic wave excitation system is used in a closed loop, the following steps are performed to adjust... and .

[0020] Step 1: Randomly assign the phase difference value between two adjacent adjustable phase shifters in the FPGA. Phase difference between the adjustable phase shifters of the two adjacent output units Record the output power value of the mixer at this time. ;

[0021] Step 2: Adjust the phase difference between the adjustable phase shifters of two adjacent input units. Increase to The FPGA-controlled input control unit changes the phase difference between two adjacent adjustable phase shifters to... Collect the intermediate frequency data output by the mixer at this time, calculate the output power value, and obtain the output power value compared with the output power value in step 1. The difference ;

[0022] Step 3: Adjust the phase difference between the adjustable phase shifters of two adjacent output units. Increase to The FPGA-controlled output control unit changes the phase difference between two adjacent adjustable phase shifters to... Collect the intermediate frequency data output by the mixer at this time, calculate the output power value, and obtain the output power value compared with the output power value in step 1. The difference ;

[0023] Step 4: Calculate the power change gradient ;

[0024] Step 5: Update = ,in The step size specified by the user; update = The FPGA will be updated The updated version was sent to the input control unit. The control unit sends the updated phase difference value between the adjustable phase shifter of the control input unit and the adjustable phase shifter of the control output unit. and The FPGA records the mixer's output power value at this time. ;

[0025] Step 6: If Then let = ,right Update the value and repeat steps 2-5; if If the iteration stops, then stop.

[0026] This invention provides an array-reconfigurable YIG magnetostatic wave excitation system. Its working principle is as follows: the frequency and intensity of the magnetostatic waves excited and received by the input and output array transducers are determined by the radiation resistance. The analytical relationship between the radiation resistance and the magnetostatic wave number is expressed as: .in, Radiation resistance; The wavenumber of the magnetostatic wave; The intrinsic radiation resistance is related to the thickness, width, saturation magnetization of the YIG thin film, and the magnitude and direction of the applied bias magnetic field. In this invention, it is controlled. The unit factor is related to the width of the unit transducer of the array transducer. In this invention, once the width of the unit transducer of the input or output array transducer is determined, this value can no longer be adjusted. The array factor of the input or output array transducer is related to the radio frequency current transmitted on each unit transducer in the input or output array transducer, and is expressed as:

[0027]

[0028] in, This refers to the number of unit transducers in the input or output array transducer, i.e., at the input end... At the output end . This is the additional phase difference between two adjacent adjustable phase shifters at the input or output terminals; specifically, at the input terminal, it is as described above. The output is as described above. . It represents the wavenumber of the static magnetic wave. The interval between two adjacent transducer units of the input or output array transducer. Based on the mathematical expression for the array factor, the additional phase difference value is determined by an adjustable phase shifter. By altering the phase of the current in each unit transducer of the input or output array transducer, the wavenumber position corresponding to the peak radiation resistance can be adjusted, thus achieving wavenumber excitation at the peak radiation resistance. The frequency of magnetostatic wave excitation is affected by dispersion relations; by changing the position of the excitation wavenumber, the frequency of the magnetostatic wave corresponding to that wavenumber position can be further excited, thereby achieving frequency control of the magnetostatic wave.

[0029] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0030] 1. This invention provides an array-reconfigurable YIG magnetostatic wave excitation system. By adjusting the additional phase of an adjustable phase shifter through an input control unit and an output control unit, the propagation characteristics of the magnetostatic wave are dynamically controlled. Compared with traditional methods that rely on adjusting magnetic field parameters such as the bias magnetic field, the electronic control method for adjusting the propagation speed of the magnetostatic wave has a higher response speed, thus enabling faster tuning.

[0031] 2. This invention provides an array-reconfigurable YIG magnetostatic wave excitation system that can precisely excite magnetostatic waves according to a preset target frequency and target wavenumber, achieving open-loop control. Compared with traditional bias magnetic field adjustment methods, this invention eliminates the need for multiple adjustments of bias magnetic field parameters to match the target excitation frequency. Instead, it directly excites magnetostatic waves of the corresponding frequency through system settings, significantly simplifying the operation process and improving excitation accuracy.

[0032] 3. This invention provides an array-reconfigurable YIG magnetostatic wave excitation system, achieving wavenumber-based excitation of magnetostatic waves, which is difficult to achieve using traditional bias magnetic field adjustment methods. This invention eliminates the need to set separate bias magnetic fields for different magnetostatic wave modes to achieve magnetostatic wave frequency tuning. For magnetostatic surface waves, magnetostatic forward volume waves, and magnetostatic backward volume waves, a unified system structure and control logic are used, eliminating the need to adjust the hardware architecture or control strategy for different modes, thus improving the system's versatility, flexibility, and scalability. Attached Figure Description

[0033] Figure 1 This is a schematic diagram of the array-reconfigurable YIG magnetostatic wave excitation system of the present invention;

[0034] Figure 2 The curve showing the relationship between radiation resistance and frequency and wavenumber when the phase difference is 0 degrees.

[0035] Figure 3The curves showing the relationship between radiation resistance and frequency and wavenumber when the phase difference is 30 degrees.

[0036] Figure 4 The curve shows the relationship between radiation resistance and frequency and wavenumber when the phase difference is 60 degrees. Detailed Implementation

[0037] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments.

[0038] An array-reconfigurable YIG magnetostatic wave excitation system, such as Figure 1 As shown, it includes a YIG thin film, an input array transducer, an input adjustable phase shifter group, a power distribution network, an input control unit, an output array transducer, an output adjustable phase shifter group, a power combining network, an output control unit, a mixer, an analog-to-digital converter, and an FPGA;

[0039] The input array transducer is disposed on the surface of the YIG thin film and includes N parallel input unit transducers, namely the first input unit transducer, the second input unit transducer, ..., the Nth input unit transducer, where N is a positive integer ≥ 2; the output array transducer is disposed on the surface of the YIG thin film and includes M parallel output unit transducers, namely the first output unit transducer, the second output unit transducer, ..., the Mth output unit transducer, where M is a positive integer ≥ 2; the input adjustable phase shifter group includes N input unit adjustable phase shifters, namely the first input adjustable phase shifter, the second input adjustable phase shifter, ..., the Nth input adjustable phase shifter; the output adjustable phase shifter group includes M output unit adjustable phase shifters, namely the first output unit adjustable phase shifter, the second output unit adjustable phase shifter, ..., the Mth output unit adjustable phase shifter.

[0040] One end of each of the N input unit transducers is grounded, and the other end is connected to the output of each of the N input unit adjustable phase shifters. The inputs of the N input unit adjustable phase shifters are connected to the same power distribution network, and the input of the power distribution network serves as the input of the excitation system. The input control unit is connected to the N input unit adjustable phase shifters and is used to control the additional phase value of each input unit adjustable phase shifter.

[0041] One end of each of the M output unit transducers is grounded, and the other end is connected to the input of each of the M output unit adjustable phase shifters. The outputs of the M output unit adjustable phase shifters are connected to the same power combining network, and the output of the power combining network serves as the output of the excitation system. The output control unit is connected to the M output unit adjustable phase shifters and is used to control the additional phase value of each output unit adjustable phase shifter.

[0042] The two inputs of the mixer are connected to the power distribution network and the power combining network, respectively. The output of the mixer is connected to the analog-to-digital converter, and the output of the analog-to-digital converter is connected to the FPGA. The FPGA is connected to the input control unit and the output control unit.

[0043] Furthermore, the N input unit transducers in the input array transducer have equal widths and the spacing between adjacent input unit transducers is equal; the M output unit transducers in the output array transducer have equal widths and the spacing between adjacent output unit transducers is equal.

[0044] Preferably, the input unit transducer is parallel to the output unit transducer.

[0045] Preferably, the input array transducer and the output array transducer are located at the edge of the YIG thin film.

[0046] Furthermore, the YIG film can be rectangular, trapezoidal, parallelogram, or other shapes.

[0047] Furthermore, the grounding terminals of the input array transducer and the output array transducer can be located on the same side or on opposite sides of the YIG thin film.

[0048] Furthermore, the number of unit transducers in the input array transducer and the output array transducer can be equal or unequal.

[0049] Furthermore, the input array transducers and the output array transducers must not overlap in physical location.

[0050] Furthermore, the phase difference value of the phase shifter between two adjacent input units is adjustable. Constant. That is, assuming the additional phase of the adjustable phase shifter of the first input unit is 0, then the additional phase of the adjustable phase shifter of the second input unit is... The additional phase of the adjustable phase shifter in the third input unit is The additional phase of the adjustable phase shifter of the Nth input unit is... Assume the additional phase of the adjustable phase shifter in the first input unit is... The additional phase of the adjustable phase shifter in the second input unit is The additional phase of the adjustable phase shifter in the third input unit is The additional phase of the adjustable phase shifter of the Nth input unit is... .

[0051] Furthermore, the phase difference value of the adjustable phase shifter between two adjacent output units Constant. That is, assuming the additional phase of the adjustable phase shifter of the first output unit is 0, then the additional phase of the adjustable phase shifter of the second output unit is... The additional phase of the adjustable phase shifter in the third output unit is The additional phase of the adjustable phase shifter of the Mth output unit is... Assume the additional phase of the adjustable phase shifter in the first output unit is... The additional phase of the adjustable phase shifter in the second output unit is The additional phase of the adjustable phase shifter in the third output unit is The additional phase of the adjustable phase shifter of the Mth output unit is... .

[0052] Furthermore, the phase difference value of the adjustable phase shifter between two adjacent output units Phase difference between the adjustable phase shifters of the two adjacent input units They can be the same or different.

[0053] Furthermore, the magnetostatic wave excitation system is in a bias magnetic field environment, and the direction of the magnetic field is in the plane of the YIG thin film and is consistent with the direction of the input unit transducer or the output unit transducer, or perpendicular to the direction of the input unit transducer or the output unit transducer in the plane of the YIG thin film, or perpendicular to the surface of the YIG thin film, so as to excite magnetostatic surface waves, magnetostatic backward body waves and magnetostatic forward body waves.

[0054] Furthermore, the two inputs of the mixer are connected to the power distribution network and the power combining network, respectively. The mixer mixes the two signals to an intermediate frequency (IF), which is then converted from analog to digital by the analog-to-digital converter (ADC) unit before being connected to the input of the FPGA. The output of the FPGA is connected to the input control unit and the output control unit. The FPGA can receive the output of the ADC for closed-loop control, or it can operate without receiving the ADC output for open-loop control.

[0055] Furthermore, when the FPGA does not receive the output of the analog-to-digital converter, i.e., when the magnetostatic wave excitation system is used in open loop, the FPGA controls the phase difference between the adjustable phase shifters of two adjacent input units. Phase difference between the adjustable phase shifters of the two adjacent output units All To stimulate the wave number specified by the user , For the specified wave number, This refers to the spacing between two adjacent transducer units in the input or output array transducer. Alternatively, it can be minimized first using a gradient descent algorithm. Obtain the user-specified desired frequency. The corresponding wave number Then set the phase difference value between the adjustable phase shifters of two adjacent input units. Phase difference between the adjustable phase shifters of the two adjacent output units All To stimulate the desired frequency. Among them Represents the L2 norm, The dispersion relation in YIG thin films varies with different YIG film configurations; however, this invention does not impose a specific limitation on it. For the specified desired frequency, The interval between two adjacent unit transducers of the input or output array transducer.

[0056] Furthermore, when the FPGA receives the output of the analog-to-digital converter, i.e., when the magnetostatic wave excitation system is used in a closed loop, it can precisely calibrate temperature drift, magnetic field drift, etc., to obtain accurate excitation frequency and wavenumber. In closed-loop use, it is generally desirable for the magnetostatic wave excitation frequency to be aligned with the input frequency. When the intermediate frequency output received by the FPGA reaches its maximum, the magnetostatic wave excitation frequency and the input frequency become consistent. During closed-loop adjustment, the following steps are used for adjustment. and .

[0057] Step 1: Randomly assign the phase difference value between two adjacent adjustable phase shifters in the FPGA. Phase difference between the adjustable phase shifters of the two adjacent output units Record the output power value of the mixer at this time. ;

[0058] Step 2: Adjust the phase difference between the adjustable phase shifters of two adjacent input units. Increase to The FPGA-controlled input control unit changes the phase difference between two adjacent adjustable phase shifters to... Collect the intermediate frequency data output by the mixer at this time, calculate the output power value, and obtain the output power value compared with the output power value in step 1. The difference ;

[0059] Step 3: Adjust the phase difference between the adjustable phase shifters of two adjacent output units. Increase to The FPGA-controlled output control unit changes the phase difference between two adjacent adjustable phase shifters to... Collect the intermediate frequency data output by the mixer at this time, calculate the output power value, and obtain the output power value compared with the output power value in step 1. The difference ;

[0060] Step 4: Calculate the power change gradient ;

[0061] Step 5: Calculation and will The value is updated to the calculated value, where The step size specified by the user; calculation and will The value is updated to the calculated value. The FPGA will update the value. The updated version was sent to the input control unit. The control unit sends the updated phase difference value between the adjustable phase shifter of the control input unit and the adjustable phase shifter of the control output unit. and The FPGA records the mixer's output power value at this time. ;

[0062] Step 6: If Then let = ,renew The value is Repeat steps 2-5; if If the iteration stops, then stop.

[0063] Figure 2 , 3 Figures 4 and 5 correspond to the radiation resistance as a function of frequency and wavenumber when the phase difference is 0, 30, and 60 degrees, respectively. It can be seen that as the additional phase difference increases, the frequency and wavenumber of the peak radiation resistance also gradually increase. This demonstrates the effectiveness of controlling the excitation frequency and wavenumber of the magnetostatic wave by adjusting the additional phase difference of the adjustable phase shifter in the control unit.

Claims

1. An array-reconfigurable YIG magnetostatic wave excitation system, characterized in that, This includes YIG thin films, input array transducers, input adjustable phase shifter groups, power distribution networks, input control units, output array transducers, output adjustable phase shifter groups, power combining networks, output control units, mixers, analog-to-digital converters, and FPGAs; The input array transducer is disposed on the surface of the YIG thin film and includes N parallel input unit transducers, where N is a positive integer ≥ 2; the output array transducer is disposed on the surface of the YIG thin film and includes M parallel output unit transducers, where M is a positive integer ≥ 2; the input adjustable phase shifter group includes N input unit adjustable phase shifters, and the output adjustable phase shifter group includes M output unit adjustable phase shifters; One end of each of the N input unit transducers is grounded, and the other end is connected to the output of each of the N input unit adjustable phase shifters. The inputs of the N input unit adjustable phase shifters are connected to the same power distribution network, and the input of the power distribution network serves as the input of the excitation system. The input control unit is connected to the N input unit adjustable phase shifters and is used to control the additional phase value of each input unit adjustable phase shifter. One end of each of the M output unit transducers is grounded, and the other end is connected to the input of each of the M output unit adjustable phase shifters. The outputs of the M output unit adjustable phase shifters are connected to the same power combining network, and the output of the power combining network serves as the output of the excitation system. The output control unit is connected to the M output unit adjustable phase shifters and is used to control the additional phase value of each output unit adjustable phase shifter. The two inputs of the mixer are connected to the power distribution network and the power combining network, respectively. The output of the mixer is connected to the analog-to-digital converter, and the output of the analog-to-digital converter is connected to the FPGA. The FPGA is connected to the input control unit and the output control unit.

2. The array-reconfigurable YIG magnetostatic wave excitation system according to claim 1, characterized in that, The N input unit transducers in the input array transducer have equal widths and equal spacing between adjacent input unit transducers; the M output unit transducers in the output array transducer have equal widths and equal spacing between adjacent output unit transducers.

3. The array-reconfigurable YIG magnetostatic wave excitation system according to claim 1, characterized in that, The input unit transducer is parallel to the output unit transducer.

4. The array-reconfigurable YIG magnetostatic wave excitation system according to claim 1, characterized in that, Phase difference between two adjacent input units adjustable phase shifters Constant.

5. The array-reconfigurable YIG magnetostatic wave excitation system according to claim 1, characterized in that, Phase difference between two adjacent output units Constant.

6. The array-reconfigurable YIG magnetostatic wave excitation system according to claim 1, characterized in that, When the FPGA does not receive the output of the analog-to-digital converter and the magnetostatic wave excitation system is used in open-loop operation, the FPGA controls the phase difference between the adjustable phase shifters of two adjacent input units. Phase difference between the adjustable phase shifters of the two adjacent output units All ,in For the specified wave number, The interval between two adjacent unit transducers of the input or output array transducer.

7. The array-reconfigurable YIG magnetostatic wave excitation system according to claim 1, characterized in that, When the FPGA does not receive the output of the analog-to-digital converter, and the magnetostatic wave excitation system is used in open-loop operation, the gradient descent algorithm is first used to minimize... To obtain the specified desired frequency The corresponding wave number Then set the phase difference value between the adjustable phase shifters of two adjacent input units. Phase difference between the adjustable phase shifters of the two adjacent output units All ,in Represents the L2 norm, The dispersion relation in YIG thin films, For the specified desired frequency, The interval between two adjacent unit transducers of the input or output array transducer.

8. The array-reconfigurable YIG magnetostatic wave excitation system according to claim 1, characterized in that, When the FPGA receives the output of the analog-to-digital converter and the magnetostatic wave excitation system is used in closed-loop operation, the following steps are adopted for adjustment. and : Step 1: The FPGA randomly assigns the phase difference value between two adjacent adjustable phase shifters in the input unit. Phase difference between the adjustable phase shifters of the two adjacent output units Record the output power value of the mixer at this time. ; Step 2: Increase to The FPGA-controlled input control unit changes the phase difference between two adjacent adjustable phase shifters to... Collect the intermediate frequency data output by the mixer at this time, calculate the output power value, and obtain the output power value compared with the output power value in step 1. The difference ; Step 3: Put Increase to The FPGA-controlled output control unit changes the phase difference between two adjacent adjustable phase shifters to... Collect the intermediate frequency data output by the mixer at this time, calculate the output power value, and obtain the output power value compared with the output power value in step 1. The difference ; Step 4: Calculate the power change gradient ; Step 5: Update = ,in For the specified step size; update = ; FPGA will be updated The updated version was sent to the input control unit. The control unit sends the updated phase difference value between the adjustable phase shifter of the control input unit and the adjustable phase shifter of the control output unit. and Record the output power value of the mixer at this time. ; Step 6: If Then let = Repeat steps 2-5; if If the iteration stops, then stop.

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