A microwave energy beam pointing control method for space solar power station

Abstract

The present invention relates to a microwave energy beam pointing control method for a space solar power station, in which a microwave energy receiving end emits a guided beam, and a guided beam receiving antenna is arranged at the center of each antenna subarray of the microwave energy transmitting end. The control circuit automatically calculates the conjugate phase corresponding to the phase of the received signal according to the received guided beam, and the conjugate phase is used as the reference phase of the antenna subarray; an angle measuring device is arranged around each antenna subarray, and the attitude deviation of the antenna subarray relative to the reference position is calculated by receiving the guided beam. On the basis of ensuring that the center is the reference phase, the phase of each radiation unit inside the antenna subarray is adjusted, so that the transmitting beam direction of the antenna subarray automatically corrects the beam direction change caused by the attitude deviation of the antenna subarray. The present invention realizes the conjugation of the antenna subarray reference phase and the simultaneous correction of the antenna subarray beam direction based on the guided beam, making the long-distance microwave wireless energy transmission of the space solar power station feasible.

Description

Technical Field

[0001] The invention relates to a microwave energy beam pointing control method for a space solar power station, belonging to the field of space technology. Background Art

[0002] Microwave beam control and adjustment mainly include methods such as antenna mechanical pointing, closed-loop active beam pointing control based on phased array antenna array, and reverse beam control based on direction tracking array.

[0003] Due to the huge size and weight of microwave energy transmitting antennas, it is not practical in engineering to achieve a pointing accuracy higher than 0.0005° by mechanical control.

[0004] As for the active beam pointing control of phased array antenna array, it is a method based on communication and radar technology. It mainly transmits the received power intensity value to the power station through the ground receiving station. Then the power station needs to adjust the feeding phase of each subarray of the entire microwave energy transmitting antenna separately to maximize the power received on the ground. It is essentially a closed-loop control system. The implementation of this solution depends on the real-time analysis and processing of a large amount of data. At the same time, multiple combinations of phase adjustments must be made for tens of thousands of phased subarrays. The complexity and operating costs of the system are extremely high, and the response time will be greatly increased. It is difficult to achieve fast and efficient beam control in engineering, and the beam control effect is not ideal.

[0005] The reverse beam control based on the directional backtracking array is a beam control method commonly used in space solar power stations. Each antenna subarray using the reverse beam control system automatically generates microwaves that are phase-conjugated with the guided beam by receiving the guided beam, and then transmits them after amplification. In this way, the microwaves emitted by the entire microwave energy transmitting antenna will automatically return to the position where the guided beam is emitted, greatly improving the technical feasibility. However, this method can only better compensate for the change in the overall antenna beam direction caused by the position change between the antenna structure modules. If the posture of each antenna structure module changes, the beam will be transmitted along the normal direction of the antenna subarray, which will cause the beam direction deviation and the decrease in energy transmission efficiency. Summary of the invention

[0006] The technical problem solved by the present invention is: in view of the long-distance high-precision microwave wireless energy transmission needs of space solar power stations, and in view of the shortcomings of existing beam pointing control technology, a comprehensive beam control method based on antenna subarray reference phase conjugation and simultaneous correction of antenna subarray beam direction is proposed, which makes long-distance microwave wireless energy transmission of space solar power stations feasible.

[0007] The technical solution of the present invention is:

[0008] A microwave energy beam pointing control method for a space solar power station, comprising:

[0009] A steered beam is emitted by a microwave energy receiving end. A steered beam receiving antenna is arranged at the center of each antenna subarray of the microwave energy transmitting end. The control circuit automatically calculates the conjugate phase corresponding to the phase of the received signal according to the received steered beam, and the conjugate phase is used as the reference phase of the antenna subarray.

[0010] Angle measuring devices are arranged around each antenna subarray. The attitude deviation of the antenna subarray relative to the reference position is calculated by receiving the guidance beam. On the basis of ensuring that the center is the reference phase, the phase of each radiating unit inside the antenna subarray is adjusted so that the transmitting beam direction of the antenna subarray is automatically corrected due to the change in beam direction caused by the attitude deviation of the antenna subarray.

[0011] Furthermore, the microwave energy emission uses a single-frequency electromagnetic wave of 5.8 GHz, and the guided beam uses a single-frequency electromagnetic wave of 2.9 GHz.

[0012] Furthermore, the microwave energy receiving end includes a ground microwave energy receiving antenna, a guided beam transmitting antenna is arranged at the center of the ground microwave energy receiving antenna, and the guided beam transmitting antenna transmits a guided beam with a frequency of 2.9 GHz to the location of the space solar power station.

[0013] Furthermore, the space solar power station includes a microwave energy transmitting end, and a guided beam receiving antenna is arranged at the center of each antenna subarray of the microwave energy transmitting end.

[0014] Furthermore, the control circuit automatically calculates the conjugate phase corresponding to the received signal phase according to the received steering beam, and the conjugate phase is used as the reference phase of the antenna subarray, specifically:

[0015] The steered beam receiving antenna converts the received steered beam into a steered signal and outputs it to the receiving channel. The receiving channel at the center of each antenna subarray down-converts the steered signal into a baseband signal, and samples the baseband signal and converts it into a digital steered signal. After digital signal processing, the phase of the digital steered signal is calculated, and the phase of the digital steered signal is conjugated and multiplied by 2 to obtain the reference phase of the antenna subarray microwave energy transmission channel.

[0016] Furthermore, a synchronization reference signal generator is set at the microwave energy transmitting end, and the synchronization reference signals used by the guidance signal receiving channels and microwave energy beam transmitting channels of all antenna subarrays are derived from the synchronization reference signal generator, so that the down-converted local oscillator signals and sampling clock signals of the guidance signal receiving channels of all antenna subarrays are phase-synchronized.

[0017] Furthermore, the output signal of the synchronization reference signal generator is converted into multiple synchronization reference signals with the same frequency through a power divider, and is provided to the frequency synthesizer of each antenna subarray receiving channel respectively.

[0018] Furthermore, the signal generated by the synchronization reference signal generator is converted into an optical signal through an electro-optical converter, and then formed into a multi-path synchronization optical signal through an optical splitter, which is transmitted to each antenna subarray through optical fiber, and then converted into a synchronization reference signal through an optoelectronic converter and provided to the frequency synthesizer.

[0019] Furthermore, the signal generated by the synchronization reference signal generator is radiated by the antenna to form a synchronization signal electromagnetic wave. Each antenna subarray is provided with a synchronization reference signal receiving antenna. The synchronization reference signal receiving antenna converts the synchronization signal electromagnetic wave into a synchronization reference signal, which is provided to the frequency synthesizer after filtering and amplification.

[0020] Furthermore, the angle measuring device includes: a DOA measurement processing module, a beam control processing module, an integrated control module and a subarray phase shifter;

[0021] The DOA measurement processing module obtains the direction of arrival of the guidance signal by performing phase interference processing on the multi-channel signal, and inputs the direction of arrival information into the beam control processing module. The direction of arrival is the direction in which the energy beam should point.

[0022] The beam control processing module generates the phase of each radiating unit in the microwave energy emitting subarray according to the processing result of the DOA measurement processing module, and inputs the obtained information into the integrated control module; the integrated control module compensates the reference phase to the phase of the radiating unit, thereby generating a control code sequence of the subarray phase shifter; the integrated control module transmits the control code sequence to the subarray phase shifter, and the subarray phase shifter executes the above control code sequence to adjust the signal phase of the radiating unit in the subarray, so that the energy beam points to the direction of the incident guidance signal, thereby realizing the reverse beam control of the microwave energy emitting array.

[0023] The beneficial effects of the present invention compared with the prior art are:

[0024] 1. The present invention adopts an antenna subarray reference phase conjugation method based on a guided beam, which can well adapt to the beam pointing deviation caused by the relative position change between the microwave energy transmitting end and the energy receiving end, such as the overall orbital position change of the space solar power station, and realize automatic compensation.

[0025] 2. The present invention adopts an antenna subarray reference phase conjugation method based on a guided beam, which can well adapt to the overall beam direction changes caused by position changes (including front and back, left and right, and up and down) between antenna structure modules caused by spatial forces, thermal environment, etc., and realize automatic compensation.

[0026] 3. The present invention obtains the attitude information of the antenna subarray through the guided beam angle measurement method, so that on the basis of the reference phase of each antenna subarray, the beam direction of the antenna subarray is controlled by adjusting the phase of the antenna unit inside the antenna subarray, and the changes of the antenna subarray are corrected simultaneously.

[0027] 4. Providing an open interface in the generation of the control code for the phase shifter of the beam control device can not only compensate for the pointing control deviation caused by the sub-array attitude deviation, but also provide a control method for the system wireless calibration and soft-transferred electric field vector (REV) calibration. By compensating for the sub-array attitude deviation and recalibrating the energy emission array to a phase plane, high-precision beam pointing control can be quickly achieved under the working conditions of large-scale arrays in a space environment. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 is an overall flow chart of the method of the present invention;

[0029] Figure 2 The schematic diagram of the antenna subarray center steering beam reception, phase detection and conjugation circuit;

[0030] Figure 3 A schematic diagram of a synchronous reference signal transmission scheme based on a power divider;

[0031] Figure 4 It is a schematic diagram of a synchronous reference signal transmission scheme based on an optical splitter and an optical fiber;

[0032] Figure 5 A schematic diagram of a synchronization reference signal transmission scheme based on wireless allocation;

[0033] Figure 6 A schematic diagram of the antenna array structure for measuring the direction of the guided signal wave;

[0034] Figure 7 The block diagram of the subarray beam pointing control device. DETAILED DESCRIPTION

[0035] The specific embodiments of the present invention are further described in detail below with reference to the accompanying drawings.

[0036] The world is facing serious energy and environmental problems. The various renewable energy and new energy sources currently under development, including ground solar energy, wind energy, hydropower, nuclear energy, ocean energy, geothermal energy and bioenergy, all have problems such as unstable energy, limited total energy or safety, and it is difficult to replace the status of traditional fossil energy on a large scale. Solar energy is the most abundant and cleanest energy, but due to the influence of day and night, atmosphere and weather, the fluctuation of energy density is very large. Ground solar energy must rely on large-scale power storage devices to ensure stable power supply. In space, solar energy is not affected by seasons, day and night changes, etc., and the received energy density is high, about 1353 watts per square meter. At the same time, energy transmission is carried out through microwaves that are not affected by the atmosphere and are suitable for the frequency band, and the atmospheric loss is very small, which is very suitable for the large-scale development and utilization of solar energy. Especially in the geosynchronous orbit, it can stably receive solar radiation for 99% of the time, and can stably transmit energy to the ground fixed receiving station. Therefore, from a long-term perspective, space solar power stations (SPS-Space Power Satellite or SSPS-Space SolarPower Station) may become an important way to provide large-scale energy and solve environmental problems in the future. At present, relevant research work in this field has been carried out around the world for more than 50 years.

[0037] Space solar power stations are mainly composed of three parts: solar power generation devices, energy conversion and transmission devices, and ground energy receiving and conversion devices. Solar power generation devices convert solar energy into electrical energy; energy conversion and transmission devices convert electrical energy into microwave or laser form, and use microwave antennas or optical systems to send beams to the ground; the ground energy receiving system uses receiving antennas or battery arrays to receive beams transmitted from space, and converts them into electrical energy for use on the ground through conversion devices.

[0038] Space solar power stations focus on two transmission methods: microwave wireless energy transmission and laser wireless energy transmission. Microwave wireless energy transmission is similar to laser wireless energy transmission. Both methods first use solar cell arrays in space to convert solar energy into electrical energy, then convert electrical energy into electromagnetic waves, and then use a transmitter to transmit the electromagnetic waves to the ground, and then convert the electromagnetic waves back into electrical energy. The main difference between the microwave method and the laser method is the huge difference in wavelength (up to tens of thousands of times). According to the principle of electromagnetic wave transmission, the product of the transmitting aperture and the receiving aperture is proportional to the wavelength, so the corresponding device scale is also very different. In addition to the device scale, microwave and laser wireless energy transmission also focus on the loss of passing through the atmosphere. In order to make microwave energy more efficiently transmitted in the atmosphere, the industrial, scientific and medical (ISM) frequency band that is basically not affected by meteorological conditions such as clouds and rain is generally used, and the microwave frequency of 2.45GHz or 5.8GHz is mainly used. Laser energy transmission mainly uses the visible light or near-infrared spectrum atmospheric transparent window, but it is greatly affected by meteorological conditions such as clouds and rain. Therefore, among the dozens of space solar power station concepts proposed internationally, most of them adopt microwave wireless energy transmission, which is more suitable for future GW-level space solar power stations from the perspective of power density.

[0039] According to the current typical design, the space solar power station operates in the geostationary orbit, and the energy transmission distance exceeds 36,000 km. The size of the microwave energy transmitting antenna is on the order of 1 km, and the diameter of the ground energy receiving antenna is about 5 km. In order to achieve high-efficiency energy reception and consider the safety of energy transmission, the microwave beam accuracy is very high. If the microwave beam center deviation does not exceed 5% of the receiving antenna diameter, the beam pointing accuracy of the space solar power station to the ground is higher than 0.0005°.

[0040] Space solar power stations running in geostationary orbits are affected by various disturbances on the orbit. Space solar power stations cannot be guaranteed to be completely stationary. There is orbital drift, and the attitude of the power station will also change to a certain extent. Any slight disturbance in the relative position and attitude of the microwave energy transmitting antenna to the ground may cause the beam direction error to exceed the upper limit, and corresponding pointing adjustments are required. At the same time, the microwave energy transmitting antenna is huge in size and needs to be assembled on orbit from many antenna structure modules. Considering the influence of various forces, heat and other space environments, various deformations will occur between the antenna structure modules (here it is assumed that an antenna structure module itself does not deform, that is, the required flatness can be guaranteed). Therefore, how to comprehensively consider the attitude changes of each antenna structure module (pitch, roll, deflection around the center) and the position changes between the antenna structure modules (front and back, left and right, up and down directions of the center) caused by the overall beam direction changes also has great technical difficulties.

[0041] In response to the energy transmission needs of space solar power stations, the present invention proposes a method that can simultaneously compensate for the overall beam direction changes caused by the posture changes (pitch, roll, and yaw around the center) of each antenna structure module of the microwave energy transmitting antenna, as well as the position changes between the antenna structure modules (in the three directions of front and back, left and right, and up and down of the center), thereby making long-distance microwave wireless energy transmission of space solar power stations feasible.

[0042] The specific implementation of the present invention will be further described in detail below with reference to the accompanying drawings. Figure 1 As shown, the present invention is a high-precision beam control method based on a steered beam for long-distance microwave wireless energy transmission in a space solar power station. The method involves a steered beam transmitting system and a microwave energy transmitting antenna composed of a plurality of antenna subarrays. Figure 1 The microwave energy transmitting antenna composed of three antenna subarrays is shown, among which antenna subarray B is in the standard position and standard posture; antenna subarray C is in the standard position, but the posture has changed; antenna subarray A has changed both the position and posture. Therefore, for each antenna subarray, a steered beam receiving antenna is arranged at the center of the subarray, and phase detection is performed according to the received beam, and phase conjugation is performed through the circuit to obtain the reference phase of the antenna subarray.

[0043] In addition, each antenna subarray is equipped with a steering beam angle measuring device, which receives the steering beam through multiple steering beam receiving antennas, and obtains the attitude information of the antenna subarray through signal interference measurement, so as to perform phase calculation of each antenna unit inside the antenna subarray based on the reference phase obtained previously, and then output it to the corresponding antenna unit through the phase shifter and power amplifier, so that the antenna subarray can adjust the transmission beam to the ideal transmission direction (i.e., the corresponding transmission beam direction when the antenna subarray is not deformed) based on the reference phase. The specific implementation method is as follows:

[0044] The guidance beam uses a single-frequency electromagnetic wave of 2.9 GHz, and the microwave energy emission uses a single-frequency electromagnetic wave of 5.8 GHz, so as to filter out the mutual interference between the microwave energy emission and the guidance signal reception through the filter. Figure 2 As shown, the steered beam receiving antenna at the center of the i-th antenna subarray converts the received steered beam into a steered signal with a frequency of 2.9 GHz and a phase of The pilot signal is filtered through a 2.9GHz bandpass filter to remove clutter and interference from 5.8GHz microwave energy emission, amplified by a low-noise amplifier, and mixed with a 2.899GHz local oscillator signal. The mixer intermediate frequency output is filtered through a 10MHz bandpass filter, and the high-frequency component is filtered out and then amplified to form a frequency of 10MHz and a phase of The intermediate frequency pilot signal is sampled by the analog-to-digital converter to form a digital baseband pilot signal. After digital signal processing, the phase The final output represents A frequency synthesizer is arranged at the center of each antenna subarray, which generates the local oscillator signal of the mixer, the sampling clock signal of the analog-to-digital converter, and the reference synchronization signal provided to the measurement and control processing module according to the input synchronization reference signal.

[0045] like Figure 3 As shown, a synchronization reference signal generator is set at the microwave energy transmitting end, and the synchronization reference signals of all antenna subarrays come from the synchronization reference signal generator. The output signal of the synchronization reference signal generator is formed into multiple synchronization reference signals of the same frequency through a power divider, and is provided to the frequency synthesizer of each antenna subarray receiving channel respectively. The function of the synchronization reference signal is to ensure that the phase of the local oscillator signal of the receiving channel of all antenna subarrays is the same, to ensure the synchronous sampling of the intermediate frequency guidance signal of all antenna subarrays, and to ensure that the transmission beam frequency of all antenna subarrays is the same.

[0046] In order to reduce the weight of the synchronization reference signal transmission cable and improve the phase stability of long-distance transmission, optical fiber can be used for long-distance transmission of the synchronization reference signal. Figure 4 As shown, the signal generated by the synchronization reference signal generator is converted into an optical signal by an electro-optical converter, and then formed into a multi-channel synchronization optical signal through a splitter, which is transmitted to each antenna subarray through an optical fiber, and then converted into a synchronization reference signal by an optoelectronic converter and provided to the frequency synthesizer.

[0047] The distribution of synchronization reference signals can also be wireless. Figure 5 As shown, the signal generated by the synchronization reference signal generator is radiated by the antenna to form a synchronization signal electromagnetic wave. Each antenna subarray is provided with a synchronization reference signal receiving antenna. The synchronization reference signal receiving antenna converts the synchronization signal electromagnetic wave into a synchronization reference signal, which is provided to the frequency synthesizer after filtering and amplification.

[0048] For the 2.9 GHz guidance signal from the ground, a two-dimensional direction of arrival (DOA) measurement antenna array is installed on each sub-array, such as Figure 6 As shown. Each dimension contains 3 receiving antenna units, using the longest distance between units (L 13 and L 53 ) to obtain a long baseline to ensure the accuracy of direction finding; using the effective minimum distance between units ((L 12 -L 23 ) and (L 54 -L 43 )) Obtain a short baseline to ensure an ambiguity-free solution.

[0049] Each pilot signal receiving antenna is connected to a receiving channel, such as Figure 7 As shown. Each receiving channel implements low-noise amplification, amplitude control, and AD sampling of the local guidance signal, and feeds the 5-channel digital guidance signal into the DOA measurement processing module. The DOA measurement processing module can obtain the direction of the guidance signal by performing phase interference processing on the multi-channel signal, and input the direction information into the beam control processing module. This direction is also the direction in which the energy beam should point.

[0050] The beam control processing module generates the phase of each radiation unit in the microwave energy emission subarray according to the DOA processing result, and inputs the obtained information into the integrated control module. The integrated control module compensates the reference phase provided by the phase conjugation module to the radiation unit phase, thereby generating a control code sequence for the subarray phase shifter. The integrated control module transmits the above control code sequence to the phase shifter of the phase-controllable microwave channel of the subarray. The subarray phase shifter executes the above control code sequence and adjusts the model phase of the radiation unit in the subarray, so that the energy beam points to the direction of the incident guidance signal, realizing the reverse beam control of the ultra-large-scale microwave energy emission array.

[0051] The present invention adopts an antenna subarray reference phase conjugation method based on a guided beam, which can well adapt to the overall beam direction changes caused by position changes (including front and back, left and right, and up and down) between antenna structure modules caused by spatial forces, thermal environment, etc., and realize automatic compensation.

[0052] Parts of the present invention that are not described in detail belong to common knowledge among those skilled in the art.

Claims

1. A microwave energy beam pointing control method for a space solar power station, characterized in that include: A steered beam is emitted by a microwave energy receiving end. A steered beam receiving antenna is arranged at the center of each antenna subarray of the microwave energy transmitting end. The control circuit automatically calculates the conjugate phase corresponding to the phase of the received signal according to the received steered beam, and the conjugate phase is used as the reference phase of the antenna subarray. Angle measuring devices are arranged around each antenna subarray to calculate the attitude deviation of the antenna subarray relative to the reference position by receiving the steering beam. On the basis of ensuring that the center is the reference phase, the phase of each radiating unit inside the antenna subarray is adjusted so that the transmission beam direction of the antenna subarray automatically corrects the beam direction change caused by the attitude deviation of the antenna subarray. The control circuit automatically calculates the conjugate phase corresponding to the received signal phase according to the received steering beam, and the conjugate phase is used as the reference phase of the antenna subarray, specifically: The steered beam receiving antenna converts the received steered beam into a steered signal and outputs it to the receiving channel. The receiving channel at the center of each antenna subarray down-converts the steered signal into a baseband signal, samples the baseband signal and converts it into a digital steered signal. After digital signal processing, the phase of the digital steered signal is calculated and conjugated to the phase of the digital steered signal and multiplied by 2 to obtain the reference phase of the microwave energy transmitting channel of the antenna subarray. A synchronization reference signal generator is set at the microwave energy transmitting end. The synchronization reference signals used by the guidance signal receiving channels and microwave energy beam transmitting channels of all antenna subarrays are derived from the synchronization reference signal generator, so that the down-conversion local oscillator signals and sampling clock signals of the guidance signal receiving channels of all antenna subarrays are phase-synchronized.

2. The method for controlling microwave energy beam pointing for a space solar power station according to claim 1, characterized in that: The microwave energy emission adopts a single-frequency electromagnetic wave of 5.8 GHz, and the guided beam adopts a single-frequency electromagnetic wave of 2.9 GHz.

3. The method for controlling microwave energy beam pointing for a space solar power station according to claim 2, characterized in that: The microwave energy receiving end comprises a ground microwave energy receiving antenna, a guided beam transmitting antenna is arranged at the center of the ground microwave energy receiving antenna, and the guided beam transmitting antenna transmits a guided beam with a frequency of 2.9 GHz to the location of the space solar power station.

4. The method for controlling microwave energy beam pointing for a space solar power station according to claim 3, characterized in that: The space solar power station comprises a microwave energy transmitting end, and a guided beam receiving antenna is arranged at the center of each antenna subarray of the microwave energy transmitting end.

5. The method for controlling microwave energy beam pointing for a space solar power station according to claim 1, characterized in that: The output signal of the synchronization reference signal generator is converted into multiple synchronization reference signals with the same frequency through a power divider, and is provided to the frequency synthesizer of each antenna subarray receiving channel respectively.

6. The method for controlling microwave energy beam pointing for a space solar power station according to claim 1, characterized in that: The signal generated by the synchronization reference signal generator is converted into an optical signal by an electro-optical converter, and then formed into a multi-channel synchronization optical signal through a splitter. It is transmitted to each antenna subarray through optical fiber, and then converted into a synchronization reference signal by an optoelectronic converter and provided to the frequency synthesizer.

7. The method for controlling microwave energy beam pointing for a space solar power station according to claim 1, characterized in that: The signal generated by the synchronization reference signal generator is radiated by the antenna to form a synchronization signal electromagnetic wave. Each antenna subarray is provided with a synchronization reference signal receiving antenna. The synchronization reference signal receiving antenna converts the synchronization signal electromagnetic wave into a synchronization reference signal, which is provided to the frequency synthesizer after filtering and amplification.

8. The method for controlling microwave energy beam pointing for a space solar power station according to claim 1, characterized in that: The angle measuring device comprises: a DOA measurement processing module, a beam control processing module, an integrated control module and a subarray phase shifter; The DOA measurement processing module obtains the direction of arrival of the guidance signal by performing phase interference processing on the multi-channel signal, and inputs the direction of arrival information into the beam control processing module. The direction of arrival is the direction in which the energy beam should point. The beam control processing module generates the phase of each radiating unit in the microwave energy emitting subarray according to the processing result of the DOA measurement processing module, and inputs the obtained information into the integrated control module; the integrated control module compensates the reference phase to the phase of the radiating unit, thereby generating a control code sequence of the subarray phase shifter; the integrated control module transmits the control code sequence to the subarray phase shifter, and the subarray phase shifter executes the above control code sequence to adjust the signal phase of the radiating unit in the subarray, so that the energy beam points to the direction of the incident guidance signal, thereby realizing the reverse beam control of the microwave energy emitting array.

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