A microwave-powered system based on anti-resonant hollow core fiber

Abstract

The application discloses a microwave energy supply system based on an anti-resonant hollow core fiber. The system comprises a microwave source, a microwave transmission component and a microwave energy conversion component. The microwave transmission component comprises at least one anti-resonant hollow core fiber. The first end of the microwave transmission component is connected with the microwave source, and the second end is connected with the microwave energy conversion component. The microwave source converts electric energy into microwaves and then outputs the microwaves to the microwave transmission component; the microwave transmission component transmits the microwaves from the microwave source; and the microwave energy conversion component converts the received microwaves into other forms of energy. The vector Helmholtz equation set of the microwaves is constructed by representing the cross-sectional components of the hollow core in terms of the longitudinal electric field components and the longitudinal magnetic field components, and the thickness of the tube wall of the capillary is determined by accurately determining the refractive index of the hollow core. The system effectively reduces the energy transmission cost, the transmission characteristics of the anti-resonant hollow core fiber can reduce the microwave transmission loss to not more than 2.57% per kilometer, and the energy consumption capacity is improved.

Description

Technical Field

[0001] This application relates to the field of energy conversion and transmission technology, and in particular to a microwave power supply system based on anti-resonant hollow optical fiber. Background Technology

[0002] Traditional power transmission relies primarily on cables, especially copper cables. However, the scarcity and high cost of copper resources pose significant challenges to this method of energy transmission. Furthermore, traditional energy development and utilization methods, such as the use of fossil fuels, not only easily lead to resource waste but also potentially cause serious environmental pollution problems. Currently, some countries or regions possess large amounts of underutilized waste energy, such as solar and wind power. However, due to the limited capacity of energy-producing regions to absorb this energy, and the prohibitively high cost of long-distance energy transmission, the vast majority of energy that cannot be absorbed or transmitted over long distances ultimately ends up being wasted, which is a great pity. How to save energy transmission costs and improve energy absorption capacity has become an urgent technical challenge in the field of energy conversion and transmission technology. Summary of the Invention

[0003] To address the aforementioned issues, this application provides a microwave power supply system based on anti-resonant hollow optical fiber, aiming to save energy transmission costs and improve energy absorption capacity.

[0004] The embodiments of this application disclose the following technical solutions: This application provides a microwave power supply system based on anti-resonant hollow optical fiber, the system comprising: A microwave source, a microwave transmission component, and a microwave energy conversion component; the microwave transmission component includes at least one anti-resonant hollow optical fiber. The first end of the microwave transmission component is connected to the output end of the microwave source, and the second end of the microwave transmission component is connected to the input end of the microwave energy conversion component. The microwave source is used to convert electrical energy into microwaves and then output them to the microwave transmission component. The microwave transmission component is used to transmit microwaves from the microwave source; The microwave energy conversion component is used to convert microwaves received from the microwave transmission component into other forms of energy; The anti-resonant hollow fiber comprises an outer cladding and a hollow core; multiple sets of capillaries are distributed on the inner periphery of the cladding; the cross-sectional components of the hollow core are represented by longitudinal electric and magnetic field components to construct a set of vector Helmholtz equations for microwaves, calculate the microwave propagation coefficient β in the hollow core, and inversely determine the refractive index of the hollow core. Refractive index based on hollow core Determine the wall thickness of the capillary.

[0005] In an optional implementation, the vector Helmholtz equations are: , , in, This represents the second-order transverse Laplace operator. Represents the longitudinal component of the microwave electric field. This represents the longitudinal component of the microwave magnetic field. This indicates the wavenumber of microwaves in the hollow core medium. This represents the propagation coefficient of microwaves within the hollow core.

[0006] In the optional implementation, the formula for microwave propagation in an anti-resonant hollow fiber, which determines the tube wall thickness, is: , Where t is the capillary wall thickness, m is the order, and λ is the number of capillaries. m Let n be the wavelength of the m-th harmonic, and n1 be the refractive index of the capillary wall. The refractive index of microwaves in the hollow inner medium ， This represents the wavenumber of microwaves in a vacuum.

[0007] In an optional implementation, the anti-resonant hollow fiber includes an outer cladding and a hollow core; multiple sets of capillaries are distributed on the inner periphery of the cladding; the wall thickness of the capillaries is designed based on the anti-resonance window of microwaves in the anti-resonant hollow fiber, the refractive index of the capillary wall, and the refractive index in the hollow core.

[0008] In an optional implementation, each set of capillaries is a nested capillary structure, which includes a first capillary and a second capillary nested within the first capillary; the wall thickness of the first capillary is a first thickness, and the wall thickness of the second capillary is a second thickness.

[0009] In an optional implementation, the first thickness and the second thickness are not equal; The first thickness is designed based on the anti-resonance window of the microwave in the first transmission band of the anti-resonance hollow fiber, the refractive index of the tube wall of the first capillary, and the refractive index in the hollow core. The second thickness is designed based on the anti-resonance window of the microwave in the second transmission band of the anti-resonance hollow fiber, the refractive index of the tube wall of the second capillary, and the refractive index in the hollow core.

[0010] In an optional implementation, the first thickness and the second thickness are equal.

[0011] In an optional implementation, each set of capillaries is coated with a coating; the coating is used to additionally provide a reflective interface to enhance the anti-resonance effect of the anti-resonant hollow fiber.

[0012] In an optional implementation, the coating is a metal layer or a dielectric coating.

[0013] In an optional implementation, the material of the metal layer includes gold, silver, or silver iodide.

[0014] In an optional implementation, the dielectric coating material includes a multilayer oxide or a multilayer fluoride.

[0015] In an optional implementation, the microwave transmission component includes multiple anti-resonant hollow optical fibers and a reflective component disposed between each pair of adjacent anti-resonant hollow optical fibers; the reflective component is used to reflect the microwave output from one adjacent anti-resonant hollow optical fiber to the other adjacent anti-resonant hollow optical fiber.

[0016] In an optional implementation, the reflective component includes: a first collimator, a reflector, and a second collimator; The first collimator is used to collimate and transmit the microwave output from an anti-resonant hollow fiber adjacent to the reflector to the reflector. The reflector is used to reflect the received microwaves to the second collimator; The second collimator is used to collimate the microwave reflected by the mirror and transmit it to another anti-resonant hollow optical fiber adjacent to the reflecting component.

[0017] In an optional implementation, the microwave energy conversion component includes: a thermal energy conversion device; The thermal energy conversion device is used to convert microwaves received from the microwave transmission component into thermal energy.

[0018] In an optional implementation, the thermal energy conversion device includes a boiler; the microwave energy conversion assembly further includes a turbine, a condenser, and a generator. The liquid in the boiler absorbs the energy of the microwaves received from the microwave transmission component and converts it into steam; The turbine is used to further drive the generator to generate electricity under the drive of the steam; The condenser is used to cool the remaining steam after driving the turbine, and to recycle the cooled and reduced liquid back into the boiler.

[0019] In an optional implementation, the liquid is water or a liquid organic substance with a boiling point lower than that of water.

[0020] In an optional implementation, the microwave energy conversion component includes a rectifier antenna; the rectifier antenna includes a receiving antenna and a rectifier circuit; the receiving antenna is electrically connected to the rectifier circuit; The receiving antenna is used to receive microwaves from the microwave transmission component and transmit the received microwaves to the connected rectifier circuit. The rectifier circuit is used to convert the microwaves transmitted by the receiving antenna into electrical energy.

[0021] In an optional implementation, the receiving antenna is an antenna array, which includes multiple sub-antenna elements; the rectifier circuit includes multiple rectifier modules; there is a one-to-one correspondence between the multiple sub-antenna elements and the multiple rectifier modules; and the multiple rectifier modules are connected in parallel with each other.

[0022] In an optional implementation, the receiving antenna is a circularly polarized helical antenna array.

[0023] In an optional implementation, the receiving antenna is a slot antenna or a Vivaldi-type broadband antenna.

[0024] In optional implementations, the rectifier circuit is a bridge rectifier circuit, a multi-unit parallel single Schottky rectifier circuit, or a rectifier circuit with matched network optimization.

[0025] In optional implementations, the microwave power supply system based on anti-resonant hollow fiber also includes: a frequency modulation module and a transmitting antenna; The frequency modulation module includes a microwave receiving unit, a frequency control unit, and a power amplifier. The end of the frequency modulation module is also provided with a radio frequency output port; the radio frequency output port is connected to the transmitting antenna. The microwave receiving unit is used to receive microwaves output from the second end of the microwave transmission component; The frequency control unit is used to perform frequency conversion on the microwaves received by the microwave receiving unit; The power amplifier is used to amplify the power of the microwaves that have undergone frequency conversion by the frequency control unit; The transmitting antenna is used to transmit the amplified microwave output from the radio frequency output port into free space.

[0026] In an optional implementation, the microwave power supply system based on anti-resonant hollow fiber further includes: a modulator, which is disposed between the second end of the microwave transmission component and the input end of the microwave energy conversion component; The modulator is used to adjust the wavelength range of the microwaves output from the second end of the microwave transmission component and transmit the wavelength-adjusted microwaves to the input end of the microwave energy conversion component; the microwaves output from the output end of the modulator are more easily absorbed by water than the microwaves input from the input end of the modulator. The modulator is a microwave frequency modulator.

[0027] In an optional implementation, the microwave frequency modulator is one of the following: an RF mixer, a microwave photonic frequency converter, or a frequency multiplier.

[0028] In an optional implementation, the microwave source and the power generation system are connected via a cable; the power generation system is any one of the following: Wind power generation system, nuclear power generation system, solar thermal power system, photovoltaic power generation system, thermal power generation system, tidal power generation system, or hydropower generation system.

[0029] Compared with the prior art, this application has the following beneficial effects: The microwave power supply system based on antiresonant hollow fiber proposed in this application includes: a microwave source, a microwave transmission component, and a microwave energy conversion component. The microwave transmission component includes at least one antiresonant hollow fiber. A first end of the microwave transmission component is connected to the output end of the microwave source, and a second end of the microwave transmission component is connected to the input end of the microwave energy conversion component. The microwave source converts electrical energy into microwaves and outputs them to the microwave transmission component; the microwave transmission component transmits the microwaves from the microwave source; and the microwave energy conversion component converts the microwaves received from the microwave transmission component into other forms of energy.

[0030] As can be seen, in this system, the microwave source completes the task of converting electrical energy into microwaves, the microwave transmission component containing anti-resonant hollow optical fiber is responsible for handling the transmission of microwaves, and finally the microwave energy conversion component completes the task of converting microwaves into other forms of energy.

[0031] On the one hand, microwave antiresonant hollow-core optical fibers are larger than conventional cables, but their production and processing are simpler, effectively saving production costs. On the other hand, microwaves have wavelengths between 1mm and 1m, carrying far more energy than conventional optical cables can transmit. Therefore, the microwave power supply system in this solution has the advantages of low production costs and abundant resources compared to traditional cables, making it easy to achieve large-scale deployment and effectively reducing energy transmission costs. In particular, replacing cables with antiresonant hollow-core optical fibers can reduce the construction cost of ultra-high voltage technology from tens of millions of RMB per kilometer to around 100,000 RMB.

[0032] On the other hand, since microwave wavelengths are much larger than the optical bands corresponding to conventional optical cables, the electromagnetic field distribution of microwaves is more sensitive to boundary conditions, and the longitudinal field component is usually not negligible (the longitudinal component of the optical band corresponding to conventional optical cables is approximately zero, and the propagation coefficient β in the hollow core can be directly replaced by the incident angle of the light). In this application, the scheme is set to represent the cross-sectional components of the hollow core with the longitudinal electric field component and the longitudinal magnetic field component to construct the vector Helmholtz equations of microwaves, which can accurately obtain the propagation coefficient β of microwaves in the hollow core. The size of the anti-resonant hollow fiber is set based on the accurate propagation coefficient β, which can effectively improve the performance of the anti-resonant hollow fiber and further reduce the energy loss in the microwave power supply system transmission process.

[0033] On the other hand, a reflective component is provided between each pair of adjacent anti-resonant hollow optical fibers. Since the size of the anti-resonant hollow optical fiber is much larger than that of conventional optical fiber, the length of a single anti-resonant hollow optical fiber is much smaller than that of conventional optical cable in order to facilitate the installation and transportation of the equipment. A reflective component is provided between two adjacent optical fibers. The reflective component can recover the microwaves in the capillary of the front optical fiber and inject them into the hollow core of the rear optical fiber, further reducing the microwave transmission loss.

[0034] On the other hand, the capillaries are coated with a layer that increases the probability of surface reflection. This coating also reduces microwave leakage into the capillaries. Combined with the reflective components that recover microwaves concentrated within the capillaries, this further reduces microwave transmission loss. The transmission characteristics of anti-resonant hollow-core optical fibers can reduce microwave transmission loss to no more than 2.57% per kilometer (better than the transmission loss of ultra-high voltage). This reduction in energy transmission loss also helps improve energy utilization capacity. Attached Figure Description

[0035] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0036] Figure 1 A schematic diagram of a microwave power supply system based on anti-resonant hollow optical fiber provided for an embodiment of this application; Figure 2 This is a schematic diagram of the cross-sectional structure of an anti-resonant hollow optical fiber in a microwave transmission component according to an embodiment of this application; Figure 3 This is a schematic diagram of the cross-sectional structure of an anti-resonant hollow fiber in another microwave transmission component according to an embodiment of this application; Figure 4 This is a schematic diagram of the structure of a microwave transmission component in an embodiment of this application; Figure 5 This is a schematic diagram of the structure of a reflective component in an embodiment of this application; Figure 6 For use Figure 5 The diagram shows the structure of the microwave transmission component of the reflective component. Detailed Implementation

[0037] As described earlier, saving energy transmission costs and improving energy utilization capacity have become urgent technical challenges in the field of energy conversion and transmission. Clearly, traditional cable-based energy transmission methods suffer from high deployment costs. Furthermore, some energy-producing regions cannot fully utilize their generated energy locally, such as solar and wind power, and cost constraints limit the widespread transmission of locally absorbed energy. In addition, cable-based energy transmission relies on ultra-high voltage (UHV) technology, which is extremely expensive, hindering efficient energy conversion.

[0038] The inventors, through research, proposed a microwave power supply system based on antiresonant hollow optical fiber. This system mainly includes a microwave source, a microwave transmission component, and a microwave energy conversion component. The microwave source is responsible for converting electrical energy into microwaves, the microwave transmission component containing the antiresonant hollow optical fiber handles microwave transmission, and the microwave energy conversion component converts the microwaves into other forms of energy. This system uses antiresonant hollow optical fiber as the microwave transmission carrier, which not only significantly reduces costs but also further reduces transmission loss. In this way, the aforementioned problems can be solved.

[0039] To enable those skilled in the art to better understand the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present application, and not all embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present application.

[0040] See Figure 1 This figure is a schematic diagram of a microwave power supply system based on anti-resonant hollow optical fiber provided in an embodiment of this application. Figure 1 As shown, the microwave power supply system based on anti-resonant hollow fiber mainly includes: The system includes a microwave source 100, a microwave transmission component 200, and a microwave energy conversion component 300; wherein the microwave transmission component 200 includes at least one anti-resonant hollow optical fiber. A first end of the microwave transmission component 200 is connected to the output end of the microwave source 100, and a second end of the microwave transmission component 200 is connected to the input end of the microwave energy conversion component 300. Figure 1The middle arrow shows the direction of microwave transmission in the system.

[0041] In such Figure 1 In the entire microwave power supply system based on antiresonant hollow optical fiber shown, the microwave source 100 and the microwave energy conversion component 300 are each connected to the outside environment. The microwave source 100 is responsible for receiving electrical energy transmitted from the outside environment, converting the received electrical energy into microwaves, and then outputting it to the microwave transmission component 200, which then completes the subsequent transmission of the microwaves. Based on its connection with the microwave source 100, the microwave transmission component 200 can receive microwaves from the microwave source 100 and realize the transmission of microwaves from one end to the other within the component itself. Based on its connection with the microwave transmission component 200, the microwave energy conversion component 300 can receive microwaves transmitted from the microwave transmission component 200 and convert the received microwaves into other forms of energy.

[0042] In practical applications, the microwave source 100 can be connected to an external power generation system via a cable. The power generation system can be any of the following: wind power, nuclear power, solar thermal power, photovoltaic power, thermal power, tidal power, or hydropower. The power generation system converts a specific type of energy into electrical energy and then transmits the electrical energy to the microwave source 100. Thus, the microwave source 100 can acquire electrical energy and then convert it into microwaves for transmission within the system. Therefore, for energy sources such as wind, nuclear, solar, solar, combustion heat, tidal, and hydropower from energy production sites, if these can be converted into electrical energy by the power generation system and then connected to the microwave power supply system based on anti-resonant hollow optical fiber described in this embodiment, they can be transmitted to a remote location in microwave form and then converted into other forms of energy, such as electrical energy, for consumption at the remote location.

[0043] The microwave source 100, also known as a microwave generator, can be implemented using a magnetron, traveling wave tube, or klystron. Magnetrons have power ratings ranging from several hundred watts to tens of kilowatts, traveling wave tubes can reach tens of kilowatts, and klystrons range from several hundred watts to several megawatts, meaning they can reach the megawatt level. In practical applications, the choice of magnetron, traveling wave tube, or klystron as the microwave source 100 depends on the power output requirements of the power generation system it is connected to, performing the conversion of electrical energy to microwaves. For example, if the power output requirements of the power generation system reach the megawatt level, a klystron can be selected as the microwave source 100 in a microwave power supply system based on anti-resonant hollow optical fiber.

[0044] The microwave power supply system based on antiresonant hollow optical fiber described in this application involves a microwave source 100 that converts electrical energy into microwaves, a microwave transmission component 200 containing antiresonant hollow optical fiber that handles microwave transmission, and a microwave energy conversion component 300 that converts the microwaves into other forms of energy. On one hand, optical fibers have advantages over traditional cables in terms of low cost and abundant resources, making them easy to deploy on a large scale and effectively reducing energy transmission costs. In particular, replacing cables with antiresonant hollow optical fiber can reduce the construction cost of ultra-high voltage technology from tens of millions of RMB per kilometer to around 100,000 RMB. On the other hand, the transmission characteristics of antiresonant hollow optical fiber can reduce microwave transmission loss to no more than 2.57% per thousand kilometers (better than the transmission loss of ultra-high voltage). This reduction in energy transmission loss also helps improve the energy absorption capacity.

[0045] The microwave transmission component 200 described above is a key component for saving transmission costs, reducing transmission loss, and improving energy absorption capacity. The anti-resonant hollow-core optical fiber within it will be described in detail below. In this application, the number of anti-resonant hollow-core optical fibers in the microwave transmission component 200 can be one, two, or more, depending on the energy transmission distance and the deflection requirements influenced by the terrain or facilities in the transmission scenario.

[0046] Unlike ordinary optical fibers, antiresonant hollow-core optical fibers are characterized by a hollow core with periodically arranged capillaries. This application utilizes an antiresonance mechanism to confine microwaves of a specific wavelength within the hollow core. Figure 2 This is a schematic diagram of the cross-sectional structure of an anti-resonant hollow optical fiber in a microwave transmission assembly according to an embodiment of this application. Figure 2 As shown, the anti-resonant hollow-core fiber includes a cladding 201 and a hollow core 202. Multiple sets of capillaries 203 are distributed around the inner periphery of the cladding 201. In the anti-resonant hollow-core fiber, the multiple sets of capillaries 203 are typically uniformly distributed. The central region of the hollow core 202 is filled with gas or a low-refractive-index medium. Here, low refractive index means that the refractive index of the medium in the central region is lower than the refractive index of the capillary wall 203. In practical applications, the gas filling the central region of the hollow core 202 can be air or other types of gaseous media with a refractive index lower than the refractive index of the capillary wall 203.

[0047] Figure 2 The anti-resonant hollow fiber shown in the image contains six sets of capillaries 203. In practical applications, the number of sets of capillaries 203 in the anti-resonant hollow fiber is not limited to six; for example, eight or ten sets can also be used. Figure 2 The cross-sectional effect shown is not intended to limit the anti-resonant hollow fiber structure within the microwave transmission component in the embodiments of this application.

[0048] In this embodiment, the microwave power supply system based on anti-resonant hollow fiber can set the size of the anti-resonant hollow fiber to match the selected microwave wavelength, thereby enabling microwave propagation under the transmission conditions of the anti-resonant hollow fiber. Specifically, in the anti-resonant hollow fiber, the wall thickness of the capillary is designed based on the anti-resonance window of the microwave in the anti-resonant hollow fiber, the refractive index of the capillary wall, and the refractive index in the hollow core. See the formula (1) below for the propagation of microwaves in the anti-resonant hollow fiber: , In formula (1), t is the wall thickness of the capillary, and λ is the wall thickness of the capillary. m Let n be the m-th harmonic wavelength, n1 be the refractive index of the capillary wall, and n2 be the refractive index of the hollow core in the anti-resonant hollow fiber. If the microwave wavelength is λ, when the microwave wavelength λ is within the anti-resonant window (λ... m+1 , λ m Within ) time, that is: λ m+1 <λ<λ m Microwaves of wavelength λ can propagate with low loss within an anti-resonant hollow fiber with the parameters shown in formula (1). Formula (1) indicates that the upper boundary λ of the anti-resonant window... m The refractive index n1 of the capillary wall, the refractive index n2 inside the hollow core of the anti-resonant hollow fiber, and the capillary wall thickness t are all related. Therefore, t can be designed based on the microwave anti-resonance window, the refractive index of the capillary wall, and the refractive index of the hollow core. It should be noted that in practical applications, once the capillary wall thickness is determined, the anti-resonance window can be known first, and then a suitable microwave can be selected based on the anti-resonance window. Alternatively, if the wavelength of the microwave to be transmitted is known, the range of the anti-resonance window can be determined based on this wavelength, and then the capillary wall thickness can be set based on this range.

[0049] The conventional Helmholtz equations, used to describe the propagation and resonance of steady-state waves in optical fibers, are as follows: , , in, This represents the second-order transverse Laplace operator. Represents the electric field components of the cross section. The magnetic field components of the cross section are represented. The wave number (k= Where n is the refractive index of the wave in the propagation medium. (This refers to the wave number of a wave or microwave in a vacuum.)

[0050] In existing optical cables, the propagation modes in their optical frequency bands can typically be represented as linearly polarized modes (LP modes) under the weak-conductivity approximation. LP modes are considered to have no longitudinal component; therefore, the propagation constant within the optical cable is directly replaced by the equivalent angle of incidence of the light ray, i.e. , Let be the refractive index of the wave in the medium inside the optical cable, so that the scalar wave equation can be used for approximate solution.

[0051] The wave equation for the optical frequency band of existing optical cables can be directly expressed as: , in, Represents the cross-sectional components of the optical cable. This represents the angle of incidence of the wave.

[0052] However, microwave wavelengths are much larger than the optical bands of existing optical cables, making the electromagnetic field distribution more sensitive to boundary conditions, and the longitudinal field component cannot be ignored. In this case, the propagation mode is no longer suitable for the LP approximation; instead, a complete solution must be derived from the full vector Maxwell's equations. The mode is essentially a hybrid mode (HE / EH), not the scalar approximation mode commonly used in optical analysis. Simply applying the LP mode approximation for the propagation constant in the optical band would be ineffective. This approach neglects the crucial longitudinal field component, leading to increased transport loss in the designed antiresonant hollow fiber. Therefore, the cross-sectional components of the hollow core of the antiresonant hollow fiber are represented by the longitudinal electric and magnetic field components. A set of vector Helmholtz equations for microwaves is constructed, and the propagation coefficient β of microwaves at a given wavelength within the hollow core is calculated by solving the vector Helmholtz equations.

[0053] Specifically: The form of microwaves is e jωt The mode of microwave propagation in an antiresonant hollow fiber is determined by the following equation: , , Where x, y, and z represent the three axes in the spatial coordinate system (the z-axis is the length direction of the hollow fiber). and Let E'(x,y) and H'(x,y) represent the electric and magnetic field transmission states in the spatial coordinate system, respectively. Let E'(x,y) and H'(x,y) represent the cross-sectional distributions of the electric and magnetic fields within the hollow fiber, respectively. Let β be the microwave propagation coefficient. Let be the function representing microwave propagation along the z-axis.

[0054] The above formula can be rewritten in the form of vector sums: , , in, This represents the electric field components of the hollow cross-section within an anti-resonant hollow fiber. E represents the magnetic field component of the hollow cross-section within the anti-resonant hollow fiber, where z is the unit vector along the z-axis. t E represents the transverse component of the microwave electric field. z H represents the longitudinal component of the microwave electric field. t H represents the transverse component of the microwave magnetic field. z This represents the longitudinal component of the microwave magnetic field. Based on the above equation, the cross-sectional component of the hollow core is... and From the longitudinal component E z H z This is directly determined, therefore the vector Helmholtz equations constructed to solve for the propagation coefficients are as follows: , , in, This represents the second-order transverse Laplace operator. Represents the longitudinal component of the microwave electric field. This represents the longitudinal component of the microwave magnetic field. This represents the wavenumber of microwaves in the medium within a hollow optical fiber. This represents the propagation coefficient of microwaves within a hollow optical fiber.

[0055] Specifically: E represents z Second-order spatial variation within the cross-section of a hollow fiber Indicates the medium inside the hollow fiber For E z Contribution Represents the propagation coefficient within a hollow fiber. For E z The contribution of phase change along the z-axis; H represents z Second-order spatial variation within the cross-section of a hollow fiber Indicates the medium inside the hollow fiber For H z Contribution The table shows the propagation coefficient within hollow-core optical fibers. For H z The contribution of phase change along the z-axis.

[0056] By using the conventional Helmholtz equation , Replace with , This effectively avoids neglecting the influence of microwave longitudinal phase components on propagation during the solution process, and can effectively improve the propagation coefficient of anti-resonant hollow optical fibers. The accuracy.

[0057] Since the propagation coefficient β of microwaves satisfies the following formula: , in, This represents the wavenumber of microwaves in a vacuum. This represents the refractive index of microwaves within the hollow core. Based on the above formula, the refractive index of the hollow core can be determined in reverse. (Right now: Then, based on the formula for microwave propagation in anti-resonant hollow optical fiber, the wall thickness of the capillary is calculated.

[0058] The precise design of the capillary wall thickness *t* allows microwaves of a specific wavelength to undergo reflective interference at the capillary wall, creating an anti-resonance effect. This effectively suppresses microwave leakage and confines the microwaves within the hollow core, achieving highly efficient microwave confinement. Specifically, when microwaves incident from the hollow region onto the thin wall of the cladding, both transmission and reflection occur simultaneously at the thin-wall interface. By precisely controlling the capillary wall thickness, microwaves near the target transmission wavelength can be transmitted through both surfaces of the thin-wall material. When the reflected microwaves meet within the wall, they are in opposite phase, resulting in destructive interference that cancels out the interference, resulting in zero energy. This interference phenomenon prevents the incident microwaves from effectively penetrating the capillary wall and leaking outside the cladding. After interference, there is no energy inside the thin wall, which can be interpreted as energy not being able to enter the thin wall. At this point, the microwaves are reflected back to the hollow region with extremely high efficiency, confining the energy within the hollow core. This achieves undefined microwave conduction within the hollow core, significantly reducing microwave loss during transmission.

[0059] When designing and manufacturing antiresonant hollow-core optical fibers adapted to the microwave band, the requirements should be low microwave loss, high structural strength, strong thermal stability, and feasible manufacturing processes. Specific material selection must be comprehensively considered in conjunction with the operating frequency, power level, and deployment environment to ensure the long-term stable operation of the antiresonant hollow-core optical fiber structure in high-power microwave long-distance transmission scenarios. Materials that meet these requirements include, but are not limited to, low-dielectric-loss materials such as quartz glass, polytetrafluoroethylene, and polystyrene, as well as ceramic materials (including but not limited to alumina or silicon nitride).

[0060] exist Figure 2 In the example, each set of capillaries in the antiresonant hollow fiber is a single-layer structure. In other possible implementations, each set of capillaries can also be a nested structure. Such antiresonant hollow fibers with nested capillary structures can be used when employing broadband microwave sources because each nested layer within a set of capillaries provides an additional antiresonance window, thereby extending the transmission performance of the antiresonant hollow fiber.

[0061] Figure 3 This is a schematic diagram of the cross-sectional structure of an anti-resonant hollow fiber in another microwave transmission component according to an embodiment of this application. Distinguished from... Figure 2 The cross-sectional structure shown is in Figure 3 Each set of capillaries is a nested capillary structure, which includes a first capillary 203a and a second capillary 203b nested within the first capillary 203a. For ease of explanation, the wall thickness of the first capillary 203a is described as the first thickness, and the wall thickness of the second capillary 203b is described as the second thickness.

[0062] In practical applications, the first thickness and the second thickness can be set to the same value or different values. Specifically, if the microwave transmission component in a microwave power supply system based on anti-resonant hollow fiber needs to transmit microwaves of two different bands, then by setting the first thickness and the second thickness to be unequal, the anti-resonant hollow fiber with a nested capillary structure can effectively complete the above transmission task.

[0063] For example, a microwave transmission component needs to transmit microwaves in a first transmission band and microwaves in a second transmission band, wherein the first and second transmission bands have no overlap or only partial overlap. In one possible implementation, the first thickness and the second thickness are not equal. The first thickness of the first capillary 203a in the anti-resonant hollow fiber is designed based on the anti-resonance window of the microwaves in the first transmission band, the refractive index of the wall of the first capillary 203a, and the refractive index in the hollow core. The second thickness of the second capillary 203b in the anti-resonant hollow fiber is designed based on the anti-resonance window of the microwaves in the second transmission band, the refractive index of the wall of the second capillary 203b, and the refractive index in the hollow core. Ultimately, the first capillary 203a, with its high refractive index and initial thickness, enables low-loss transmission of microwaves in the first transmission band of the anti-resonant hollow fiber to the distant end; similarly, the second capillary 203b, with its high refractive index and initial thickness, enables low-loss transmission of microwaves in the second transmission band of the anti-resonant hollow fiber to the distant end. In other words, through the appropriate setting of the first and second thicknesses, the microwave transmission assembly is capable of transmitting microwaves of two different bands to the distant end for absorption.

[0064] If the nested capillaries have the same wall thickness, that is, the first thickness is equal to the second thickness, then the nested capillary structure can further reduce losses compared to a single-layer capillary with the same wall thickness. Although the transmitted microwave band is not increased, adding another layer of capillary of the same thickness will still reduce microwave transmission losses to some extent.

[0065] Figure 3The structure of the antiresonant hollow fiber with nested capillary structure shown is for illustrative purposes only. In practical applications, the number of capillaries nested in each group of capillaries in the antiresonant hollow fiber is not limited to one; it may also be two or more. For example, each group of capillaries includes a first capillary, a second capillary nested within the first capillary, and a third capillary nested within the second capillary.

[0066] In some scenarios, it may be necessary to enhance the anti-resonance effect within the anti-resonant hollow fiber. As an alternative approach, a coating can be applied to each set of capillaries during the design and manufacturing phases of the anti-resonant hollow fiber. This coating provides an additional reflective interface to enhance the anti-resonance effect of the hollow fiber and also reduces the probability of further microwave leakage into the capillaries.

[0067] The coating applied to the capillary can be a metallic layer or a dielectric coating. Optionally, the metallic layer may be made of gold, silver, or silver iodide. Optionally, the dielectric coating may be made of multilayer oxides or multilayer fluorides. Applying a coating to the capillary is equivalent to adding a highly reflective interface, thereby enhancing the power of the light initially reflected to the core of the antiresonant hollow fiber. Consequently, more light remains within the core. In other words, the coating adds a highly reflective surface to the antiresonant hollow fiber on top of the antiresonant effect, ensuring that microwaves are confined within the hollow core for continuous propagation, which helps reduce microwave transmission loss within the antiresonant hollow fiber. It should be noted that the coating does not truly change the antiresonant effect, because the antiresonant effect itself is determined by the capillary wall thickness. Compared to not applying a coating, applying a coating increases the power of the reflected light by introducing a highly reflective interface.

[0068] In practical applications, due to terrain features or infrastructure obstacles during transmission, a single anti-resonant hollow fiber in the microwave transmission assembly may not be sufficient for long-distance transmission. Therefore, in some optional implementations, the microwave transmission assembly includes multiple anti-resonant hollow fibers and a reflective assembly positioned between each pair of adjacent anti-resonant hollow fibers. The reflective assembly reflects the microwaves output from one adjacent anti-resonant hollow fiber to the next adjacent anti-resonant hollow fiber. During operation, the reflective assembly can simultaneously reflect microwaves from both the hollow core and the capillary tube to the hollow core of the next anti-resonant hollow fiber, effectively recovering microwaves transmitted into the capillary tube and reducing microwave transmission loss.

[0069] Figure 4 This is a schematic diagram of the structure of a microwave transmission component according to an embodiment of this application. Figure 4 The microwave transmission assembly shown contains a first anti-resonant hollow fiber 200a and a second anti-resonant hollow fiber 200b, from which... Figure 4It can be seen that the first anti-resonant hollow fiber 200a and the second anti-resonant hollow fiber 200b are placed at a certain angle. If the microwave source is along... Figure 4 Transmitting from left to right, the microwave can be successfully transmitted within the first anti-resonant hollow fiber 200a after connection. However, because the microwave energy conversion component is far from the second end of the first anti-resonant hollow fiber 200a or is not directly to the right of the second end of the first anti-resonant hollow fiber 200a, a second anti-resonant hollow fiber 200b needs to be connected. The microwave refracting between the first and second anti-resonant hollow fibers 200a and 200b is achieved through a reflective component 200c. In practical applications, the reflective component can be any device with microwave reflection capabilities, and its structure can be planar or three-dimensional. Furthermore, in practical applications, there can be one or multiple reflective components within the microwave transmission component, depending on the specific microwave refracting requirements of the actual scenario.

[0070] Considering that the energy of microwaves may tend to diverge after they are emitted from the anti-resonant hollow fiber, making it difficult to ensure efficient and low-loss transmission, a collimator can be further configured in the reflective component in the optional implementation. Figure 5 This is a schematic diagram of the structure of a reflective component in an embodiment of this application, such as... Figure 5 As shown, the reflection assembly includes: a first collimator 501, a reflector 502, and a second collimator 503. The first collimator 501 is used to collimate and transmit the microwave output from one anti-resonant hollow fiber adjacent to the reflection assembly to the reflector 502; the reflector 502 is used to reflect the received microwave to the second collimator 503; the second collimator 503 is used to collimate and transmit the microwave reflected by the reflector 502 to another anti-resonant hollow fiber adjacent to the reflection assembly.

[0071] Figure 6 For use Figure 5 The diagram shows the structure of the microwave transmission component of the reflective assembly. Figure 6 As shown, the first collimator 501 is positioned between the second end (microwave emission end) of the first anti-resonant hollow fiber 200a and the reflector 502, while the second collimator 503 is positioned between the reflector 502 and the first end (microwave incident end) of the second anti-resonant hollow fiber 200b. Thus, the first collimator 501 collimates the microwave emitted from the first anti-resonant hollow fiber 200a before transmitting it to the reflector. To ensure efficient transmission of the microwave incident on the second anti-resonant hollow fiber 200b, the second collimator 503 performs another collimation process on the microwave before it is incident on the second anti-resonant hollow fiber 200b.

[0072] Since optical fiber is an insulator, there is no risk of electric shock, which greatly reduces the personal safety threats to construction and maintenance personnel during line construction and daily maintenance.

[0073] The microwave power supply system based on antiresonant hollow fiber proposed in this application uses antiresonant hollow fiber instead of ordinary single-mode or multimode fiber. The upper limit of energy transmission for antiresonant hollow fiber can reach gigawatts to ten gigawatts, while the upper limit of energy transmission for ordinary single-mode and multimode fibers is one to ten watts, which cannot meet the demand for high-power energy transmission. Furthermore, when transmitting high-power laser signals (such as 10 kW lasers), the loss of antiresonant hollow fiber is no more than 2.57% per kilometer, while the loss of energy-transmitting fibers specifically designed for high-energy transmission reaches approximately 98% per kilometer, which cannot meet the needs of long-distance transmission. In addition, traditional energy-transmitting fibers cannot propagate microwaves, only lasers. However, when transmitting high-power microwaves, the transmission loss of antiresonant hollow fiber can be reduced from 2.57% per kilometer when transmitting lasers to less than 2.57% per thousand kilometers.

[0074] There are three main causes of power loss when using optical fibers: absorption loss of the transmitted signal within the fiber, backscattering loss (Rayleigh scattering, Brillouin scattering, and Raman scattering), and bending loss. Antiresonant hollow-core fibers adapted for the microwave band have a large diameter that prevents bending, thus eliminating bending loss. Furthermore, the interior of antiresonant hollow-core fibers is filled with air, so microwave absorption loss is negligible. Regarding backscattering losses, Rayleigh scattering is the most significant, followed by Brillouin scattering, with Raman scattering being the weakest. The intensity of loss due to Rayleigh scattering is inversely proportional to the fourth power of the wavelength, the intensity of loss due to Brillouin scattering is inversely proportional to the square of the wavelength, and the intensity of loss due to Raman scattering is inversely proportional to the wavelength. It is known that the power loss of anti-resonant hollow fiber in the laser band (1550nm) (mainly caused by backscattering) does not exceed 2.57% per kilometer. Therefore, when this type of fiber is used for microwave transmission, the power loss does not exceed 2.57% per thousand kilometers, while the loss of ultra-high voltage is about 3% per thousand kilometers. Therefore, it is superior to ultra-high voltage technology in terms of transmission performance.

[0075] The Jinshang-Hubei ultra-high-voltage direct current (UHVDC) project, which commenced construction in 2023, traverses mountainous provinces including Sichuan and Hubei, spanning 2,107 kilometers with a projected dynamic investment of 34.3 billion yuan, relatively high. Another UHVAC ring network, the Sichuan-Chongqing UHVAC ring network, which began construction in 2022, reaches over 1,300 kilometers, crossing mountainous regions and involving long-distance AC transmission, with a projected investment of 28.6 billion yuan, also relatively high. Generally speaking, the investment for an UHVDC line exceeding 1,000 kilometers typically ranges from 20 to 30 billion yuan. The construction cost of UHVDC is over 10 million to 20 million yuan per kilometer, while the construction cost of a fiber optic network is only tens of thousands to hundreds of thousands of yuan per kilometer. Therefore, the microwave power supply system based on anti-resonant hollow-core optical fiber proposed in this application will significantly reduce energy transportation costs without increasing energy transmission loss, or even while reducing energy transmission loss.

[0076] In the microwave power supply system based on antiresonant hollow optical fiber described above, the microwave energy conversion component receives microwaves transmitted from the microwave transmission component and converts the received microwaves into other forms of energy. The specific form of the microwave energy conversion component can be configured according to requirements.

[0077] In one alternative implementation, the microwave energy conversion component converts the received microwaves into heat energy or further converts the heat energy into electrical energy. In this implementation, the microwave energy conversion component includes a heat conversion device; the heat conversion device converts the microwaves received from the microwave transmission component into heat energy. The following is a description of a specific implementation structure of the heat conversion device: The thermal energy conversion equipment includes a boiler; the microwave energy conversion assembly further includes a turbine, a condenser, and a generator. In the boiler, the liquid absorbs the energy of microwaves received from the microwave transmission assembly and converts it into steam. The turbine, driven by the steam, further drives the generator to produce electricity. The condenser cools the remaining steam after driving the turbine, and the cooled, reduced liquid is then recycled back into the boiler. Through this process, the microwave energy conversion assembly successfully completes the conversion from microwaves to thermal energy and then to electrical energy. Furthermore, the use of a condenser in the microwave energy conversion assembly successfully achieves the recycling of steam, saving resource costs.

[0078] Generally, in the process of generating electricity using steam, the efficiency of converting heat energy into electrical energy is between 25% and 45%. This application uses anti-resonant hollow optical fiber to transmit microwaves and converts the microwave energy into heat energy first, and then into electrical energy. The efficiency of the microwave source in converting electrical energy into microwaves is about 70%. Transmission loss is almost negligible. Therefore, by utilizing the path of converting microwaves into heat energy and then into electrical energy in this invention, the utilization rate of waste energy can reach 17.5%-31%.

[0079] In practical applications, the liquid in the boiler is water or liquid organic substances with boiling points lower than water, including but not limited to propane and butane. Because propane and butane have low boiling points, they can generate steam at relatively low temperatures to drive turbines and generators. Therefore, their vapor pressure is also lower than that of water vapor, allowing for thinner boilers, simpler pumps, and sealing systems, thus improving system safety. Furthermore, although these organic substances have lower boiling points than water, their condensation temperatures are often higher, meaning that powerful condensation systems are not required to condense the vapor into liquid for recycling. Although these organic substances are more expensive than water, their properties make them suitable for power generation in water-scarce regions (where water cooling is costly) or in applications lacking cooling towers.

[0080] In another alternative implementation, the microwave energy conversion component converts the received microwaves into electrical energy. In this implementation, the microwave energy conversion component includes a rectifier antenna; the rectifier antenna specifically includes a receiving antenna and a rectifier circuit; the receiving antenna and the rectifier circuit are electrically connected. The receiving antenna receives microwaves from the microwave transmission component and transmits the received microwaves to the connected rectifier circuit; the rectifier circuit converts the microwaves transmitted by the receiving antenna into electrical energy.

[0081] Depending on the usage requirements, the above-mentioned receiving antenna can be implemented in several specific ways, as listed below: (1) The receiving antenna is an antenna array, which includes multiple sub-antenna elements, forming a receiving matrix. The rectifier circuit includes multiple rectifier modules; there is a one-to-one correspondence between the multiple sub-antenna elements and the multiple rectifier modules; the multiple rectifier modules are connected in parallel. Each sub-antenna element is responsible for receiving and transmitting a portion of the microwave to its corresponding rectifier module. The multiple rectifier modules are connected in parallel to form the total DC output. The antenna array receiving antenna has good power sharing capability and scalability, and is suitable for high output power requirements. The array form can be flexibly arranged according to the spatial layout, supporting flat packaging, modular thermal management and distributed control, which is the basic design scheme for realizing high-efficiency, large-area, and high-power microwave reception.

[0082] (2) The receiving antenna is a circularly polarized helical antenna array. In application scenarios with high requirements for attitude adaptability, this application can use a circularly polarized helical antenna array as the receiving antenna structure. This type of antenna can effectively alleviate the efficiency reduction caused by the mismatch between the microwave receiving direction and the polarization angle, and is suitable for receiving microwave energy on moving platforms, rotating equipment, or space carriers. Multiple circularly polarized antenna elements in the circularly polarized helical antenna array can work together in the array structure to jointly support the total output power of the system, which can meet the power generation requirements of the power plant, and at the same time have a certain frequency adaptability and angle tolerance, which can improve the robustness of the system.

[0083] (3) The receiving antenna is a slot antenna or a Vivaldi-type broadband antenna. It is suitable for power supply systems that require high directivity, high bandwidth adaptability, or frequency tunability. This type of antenna can realize microwave reception at multiple frequency points or bandwidths, and is suitable for scenarios where the fiber optic output frequency fluctuates greatly or requires dynamic frequency modulation control. Through large-area array combination, this structure can carry a total power of tens of kilowatts or more, while having good coupling efficiency and directional gain control capability, making it suitable for high-precision power supply or focal-area beam transmission structures.

[0084] Depending on the application requirements, the above rectifier circuit can be implemented in several ways, as listed below: (1) The rectifier circuit is a bridge rectifier circuit. In microwave power supply systems based on anti-resonant hollow optical fibers, if high-power microwave power supply is required, the rectifier circuit can specifically adopt a bridge rectifier circuit. A stable and efficient DC output is achieved through a full-wave rectification structure composed of several high-speed, high-current diodes. The bridge rectifier circuit is suitable for power processing of several hundred watts per channel and can be connected in parallel through multiple rectifier channels to form an array to meet the requirements of high total output power systems. This structure has advantages such as small output voltage fluctuation, strong current continuity, and high load adaptability. It is suitable for high-load, continuous power supply, or energy storage applications, and is particularly stable and reliable in receiving environments where microwave power distribution is relatively uniform.

[0085] (2) The rectifier circuit is a multi-unit parallel single Schottky rectifier circuit. The single Schottky diode rectifier can also achieve high power output through a modular array. Each unit rectifier circuit handles microwave energy ranging from tens to hundreds of watts. Through the parallel operation of hundreds or thousands of sub-modules, the total output DC power reaches 10 kilowatts or higher. This structure features fast response speed, simple structure, and strong unit interchangeability. It is suitable for scenarios with wide power density distribution and expandable receiving surface space, such as rectifier array walls and multi-channel receiving systems. By optimizing the wiring and thermal management of the rectifier units, this structure can effectively support the high-power microwave energy conversion task of large-area spatial receiving systems.

[0086] (3) The rectifier circuit is a matching network optimized rectifier circuit. The matching network optimized rectifier structure is used to further improve the conversion efficiency of microwave energy to DC power under high power conditions. By connecting a π-type, L-type, or T-type impedance matching network in series before each rectifier channel, the antenna output and rectifier input impedance are optimally coupled, thereby reducing reflection loss and increasing rectified power capacity. This structure is particularly suitable for system environments with adjustable frequency, uneven antenna angle distribution, and large power density variations, and can achieve system output of 10 kW and above through modular array deployment.

[0087] When the operating environment of a microwave power supply system based on antiresonant hollow fiber changes, such as significant temperature or pressure variations, or when external forces are applied to the antiresonant hollow fiber, the microwave frequency output by the antiresonant hollow fiber can be appropriately adjusted to mitigate power loss due to antenna impedance drift. For microwave energy conversion components including a rectifier antenna, in optional implementations, the microwave power supply system based on antiresonant hollow fiber also includes a frequency modulation module and a transmitting antenna. The frequency modulation module includes a microwave receiving unit, a frequency control unit, and a power amplifier. The end of the frequency modulation module also has an RF output port (such as a coaxial port or waveguide port); the RF output port is connected to the transmitting antenna.

[0088] In practical applications, the microwave receiving unit can be a waveguide or collimated antenna. The frequency control unit may include a voltage-controlled oscillator (VCO), a reference frequency source, and a mixer. The power amplifier can be a GaN high-power amplifier module. Furthermore, phase modulation and amplitude modulation components can be further incorporated into the frequency modulation module to achieve phase or amplitude modulation of the microwave signal. After processing by the frequency modulation module, it can ultimately output a stable microwave signal within the target frequency range.

[0089] In this embodiment, the frequency modulation module is located at the microwave output end of the microwave transmission component. The microwave signal transmitted by the microwave transmission component is released into free space or the radio frequency waveguide environment at the end of the anti-resonant hollow fiber, and is then collected and introduced into the frequency modulation module. In the frequency modulation module, a microwave receiving unit is used to receive the microwaves output from the second end (microwave output end) of the microwave transmission component; a frequency control unit is used to perform frequency conversion on the microwaves received by the microwave receiving unit; and a power amplifier is used to amplify the power of the microwaves after frequency conversion by the frequency control unit.

[0090] A transmitting antenna is used to amplify the power of microwaves output from the radio frequency output port and transmit them into free space. A transmitting antenna can transmit microwaves into free space with a specific beam direction. The type of transmitting antenna can be selected based on the application requirements of the microwave. For example, if a transmitting antenna with high power handling capacity and high radiation efficiency is required, a horn antenna, microstrip array, or parabolic antenna can be selected as the transmitting antenna.

[0091] Microwaves emitted into free space can be further received by a receiving antenna in a microwave energy conversion assembly and converted into electrical energy by a rectifier circuit. The receiving antenna is responsible for capturing microwave signals in space and converting them into high-frequency alternating current (AC). The rectifier circuit then converts the AC to direct current (DC) for direct power supply, energy storage, or further regulation.

[0092] In summary, the inclusion of the frequency modulation module in the system enhances the system's anti-interference capabilities and reduces power loss caused by factors such as antenna impedance drift.

[0093] In practical applications, if the antiresonant hollow-core fiber in the system needs to be used in watery or humid environments, the microwave wavelength needs to be designed to be difficult for water vapor to absorb in order to ensure that the microwaves are not absorbed by water during transmission and to reduce transmission loss. When the system outputs microwaves, the wavelength is then modulated to be absorbed by water. In accordance with this wavelength conversion requirement, the microwave power supply system based on antiresonant hollow-core fiber in this embodiment further includes a modulator, which is disposed between the second end of the microwave transmission component and the input end of the microwave energy conversion component. The modulator is used to adjust the wavelength range of the microwaves output from the second end of the microwave transmission component and transmit the wavelength-adjusted microwaves to the input end of the microwave energy conversion component. The microwaves output from the modulator's output end are more easily absorbed by water than the microwaves input from the modulator's input end; that is, the modulation here causes a change in the microwave wavelength. Specifically, the modulator is a microwave frequency modulator, which affects the wavelength by modulating the frequency. As an example, the selected microwave frequency modulator can be any of an RF mixer, a microwave photonic frequency converter, or a frequency multiplier.

[0094] Furthermore, the microwave power supply system based on anti-resonant hollow optical fiber described in this application can also be used directly for heating. For example, the microwave energy conversion component in this system is connected to a heating station. The microwave energy conversion component uses the converted heat energy to heat water, thereby achieving centralized heating. Because this system can achieve long-distance microwave transmission, it can also achieve long-distance heating.

[0095] In addition, thermal energy is required in some industrial scenarios, such as metal processing, petrochemicals, food processing, and papermaking. In microwave power systems based on anti-resonant hollow optical fibers, the thermal energy converted by the microwave energy conversion component can be used to heat industrial raw materials, facilitate chemical reactions, or change the state or form of matter. The microwave energy conversion component in these systems interfaces with a remote industrial thermal energy user, converting long-distance transmitted microwaves into thermal energy for long-distance industrial applications.

[0096] In the defense sector, given the limited area of ​​garrisoned islands, there are limitations to the power supply capacity available for energy sources such as solar power. Current common methods to address this issue include transporting batteries and constructing offshore power supply vessels. However, these methods are highly vulnerable to malicious attacks. If a malicious attack leads to a power outage, all facilities on the island will also become unusable. The microwave power supply system based on anti-resonant hollow optical fiber provided in this application can transmit microwaves and convert energy using anti-resonant hollow optical fibers carried via submarine optical cables, thereby supplying power to the islands. Submarine optical cables are typically buried on the seabed, offering greater concealment and security compared to transporting batteries or constructing offshore power supply vessels, thus providing strong protection for the power supply security of garrisoned islands.

[0097] The above description is merely one specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A microwave power supply system based on anti-resonant hollow optical fiber, characterized in that, include: A microwave source, a microwave transmission component, and a microwave energy conversion component; the microwave transmission component includes at least one anti-resonant hollow optical fiber. The first end of the microwave transmission component is connected to the output end of the microwave source, and the second end of the microwave transmission component is connected to the input end of the microwave energy conversion component. The microwave source is used to convert electrical energy into microwaves and then output them to the microwave transmission component. The microwave transmission component is used to transmit microwaves from the microwave source; The microwave energy conversion component is used to convert microwaves received from the microwave transmission component into other forms of energy; The anti-resonant hollow fiber includes an outer cladding and a hollow core; multiple sets of capillaries are distributed on the inner periphery of the cladding, and each set of capillaries is coated with a coating; the coating is used to provide an additional reflective interface to enhance the anti-resonance effect of the anti-resonant hollow fiber.

2. The system according to claim 1, characterized in that, By representing the cross-sectional components of the hollow core with longitudinal electric and magnetic field components, a set of vector Helmholtz equations for microwaves is constructed. The propagation coefficient β of microwaves within the hollow core is calculated, and the refractive index of the hollow core is determined in reverse. Refractive index based on hollow core Determine the wall thickness of the capillary.

3. The system according to claim 2, characterized in that, The vector Helmholtz equations are: ， ， in, This represents the second-order transverse Laplace operator. Represents the longitudinal component of the microwave electric field. This represents the longitudinal component of the microwave magnetic field. This indicates the wavenumber of microwaves in the hollow core medium. This represents the propagation coefficient of microwaves within the hollow core.

4. The system according to claim 3, characterized in that, The formula for microwave propagation in an antiresonant hollow optical fiber with a given wall thickness is: ， Where t is the capillary wall thickness, m is the order, and λ is the number of capillaries. m Let n be the wavelength of the m-th harmonic, and n1 be the refractive index of the capillary wall. The refractive index of microwaves in the hollow inner medium ， This represents the wavenumber of microwaves in a vacuum.

5. The system according to claim 1, characterized in that, The wall thickness of the capillary is designed based on the anti-resonance window of the microwave in the anti-resonance hollow optical fiber, the refractive index of the capillary wall, and the refractive index in the hollow core.

6. The system according to claim 1, characterized in that, Each set of capillaries is a nested capillary structure, which includes a first capillary and a second capillary nested within the first capillary; the wall thickness of the first capillary is a first thickness, and the wall thickness of the second capillary is a second thickness.

7. The system according to claim 6, characterized in that, The first thickness and the second thickness are not equal; The first thickness is designed based on the anti-resonance window of the microwave in the first transmission band of the anti-resonance hollow fiber, the refractive index of the tube wall of the first capillary, and the refractive index in the hollow core. The second thickness is designed based on the anti-resonance window of the microwave in the second transmission band of the anti-resonance hollow fiber, the refractive index of the tube wall of the second capillary, and the refractive index in the hollow core.

8. The system according to claim 6, characterized in that, The first thickness and the second thickness are equal.

9. The system according to claim 1, characterized in that, The coating is a metal layer or a dielectric coating.

10. The system according to claim 9, characterized in that, The material of the metal layer includes gold, silver, or silver iodide.

11. The system according to claim 9, characterized in that, The dielectric coating material includes multilayer oxides or multilayer fluorides.

12. The system according to claim 1, characterized in that, The microwave transmission component includes multiple anti-resonant hollow optical fibers and a reflection component disposed between each pair of adjacent anti-resonant hollow optical fibers; the reflection component is used to reflect the microwave output from one adjacent anti-resonant hollow optical fiber to the other adjacent anti-resonant hollow optical fiber.

13. The system according to claim 12, characterized in that, The reflection assembly includes: a first collimator, a reflector, and a second collimator; The first collimator is used to collimate and transmit the microwave output from an anti-resonant hollow fiber adjacent to the reflector to the reflector. The reflector is used to reflect the received microwaves to the second collimator; The second collimator is used to collimate the microwave reflected by the mirror and transmit it to another anti-resonant hollow optical fiber adjacent to the reflecting component.

14. The system according to claim 1, characterized in that, The microwave energy conversion component includes: a thermal energy conversion device; The thermal energy conversion device is used to convert microwaves received from the microwave transmission component into thermal energy.

15. The system according to claim 14, characterized in that, The thermal energy conversion equipment includes a boiler; the microwave energy conversion assembly further includes a turbine, a condenser, and a generator. The liquid in the boiler absorbs the energy of the microwaves received from the microwave transmission component and converts it into steam; The turbine is used to further drive the generator to generate electricity under the drive of the steam; The condenser is used to cool the remaining steam after driving the turbine, and to recycle the cooled and reduced liquid back into the boiler.

16. The system according to claim 15, characterized in that, The liquid is water or a liquid organic substance with a boiling point lower than that of water.

17. The system according to claim 1, characterized in that, The microwave energy conversion component includes a rectifier antenna; the rectifier antenna includes a receiving antenna and a rectifier circuit; the receiving antenna and the rectifier circuit are electrically connected. The receiving antenna is used to receive microwaves from the microwave transmission component and transmit the received microwaves to the connected rectifier circuit. The rectifier circuit is used to convert the microwaves transmitted by the receiving antenna into electrical energy.

18. The system according to claim 17, characterized in that, The receiving antenna is an antenna array, which includes multiple sub-antenna elements; the rectifier circuit includes multiple rectifier modules; there is a one-to-one correspondence between the multiple sub-antenna elements and the multiple rectifier modules; the multiple rectifier modules are connected in parallel with each other.

19. The system according to claim 18, characterized in that, The receiving antenna is a circularly polarized spiral antenna array.

20. The system according to claim 17, characterized in that, The receiving antenna is a slot antenna or a Vivaldi-type broadband antenna.

21. The system according to claim 17, characterized in that, The rectifier circuit is a bridge rectifier circuit, a multi-unit parallel single Schottky rectifier circuit, or a rectifier circuit with optimized matching network.

22. The system according to any one of claims 17-21, characterized in that, Also includes: Frequency modulation module and transmitting antenna; The frequency modulation module includes a microwave receiving unit, a frequency control unit, and a power amplifier. The end of the frequency modulation module is also provided with a radio frequency output port; the radio frequency output port is connected to the transmitting antenna. The microwave receiving unit is used to receive microwaves output from the second end of the microwave transmission component; The frequency control unit is used to perform frequency conversion on the microwaves received by the microwave receiving unit; The power amplifier is used to amplify the power of the microwaves that have undergone frequency conversion by the frequency control unit; The transmitting antenna is used to transmit the amplified microwave output from the radio frequency output port into free space.

23. The system according to claim 1, characterized in that, Also includes: A modulator, wherein the modulator is disposed between the second end of the microwave transmission component and the input end of the microwave energy conversion component; The modulator is used to adjust the wavelength range of the microwaves output from the second end of the microwave transmission component and transmit the wavelength-adjusted microwaves to the input end of the microwave energy conversion component; the microwaves output from the output end of the modulator are more easily absorbed by water than the microwaves input from the input end of the modulator. The modulator is a microwave frequency modulator.

24. The system according to claim 23, characterized in that, The microwave frequency modulator is one of the following: an RF mixer, a microwave photonic frequency converter, or a frequency multiplier.

25. The system according to claim 1, characterized in that, The microwave source and the power generation system are connected via a cable; the power generation system is any one of the following: Wind power generation system, nuclear power generation system, solar thermal power system, photovoltaic power generation system, thermal power generation system, tidal power generation system, or hydropower generation system.

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