Blackout communication method and system based on gain metamaterials

Abstract

The application discloses a black barrier communication method and system based on gain metamaterials, an aircraft communication component and a communication method. The method aims to overcome the limitations of the existing black barrier communication method, including the problems of sacrificing the aerodynamic performance and flight load of the aircraft, atmospheric rain attenuation, weak collision environment restriction and communication equipment development, and the method is as follows: a matching system of simulated generation of plasma-gain metamaterials is generated; an incident electromagnetic wave frequency corresponding to a balanced and stable matching system is taken as a communication signal frequency; the matching system is balanced and stable, the gain and loss of the matching system are balanced, and the state of the closed characteristic value curve; when the structure of the matching system is formed by an entity gain metamaterial layer and a plasma layer at the black barrier, communication is carried out through a communication signal conforming to the communication signal frequency; the thickness and dielectric constant of the entity gain metamaterial layer and the simulated gain metamaterial layer are the same.

Description

Technical Field

[0001] This invention relates to an aircraft communication component and communication method. Background Technology

[0002] When various high-speed aircraft fly at hypersonic speeds (typically Mach 10-25) in near space, the gas surrounding the aircraft is compressed and heated by the hypersonic shock wave. The friction between air molecules and the aircraft surface triggers violent thermal motion, causing them to decompose and ionize, forming a plasma sheath that envelops the aircraft. This high-density, highly impactful, and dynamic plasma sheath attenuates and shields communication signals, leading to signal amplitude attenuation and phase distortion. This results in the interruption of radio signals for navigation, data transmission, telemetry, and remote control—a phenomenon known as the blackout. The communication interruption caused by the presence of the plasma sheath severely impacts and restricts the rapid development of manned spaceflight, deep space exploration, military equipment, and future space shuttles. The blackout problem is a pressing technical challenge that needs to be addressed.

[0003] Currently, methods for alleviating communication blackouts both domestically and internationally can be mainly divided into two categories: active methods and passive methods.

[0004] Active methods focus on controlling the spatial distribution of plasma, reducing the electron density at the antenna window, and minimizing the attenuation of electromagnetic waves in the plasma. Examples include electrophilic material injection and magnetic windowing.

[0005] The passive approach attempts to explore the feasibility of breaking through communication barriers in new electromagnetic wave frequency bands (such as Ka, THz, and laser bands).

[0006] The aforementioned blackout mitigation technologies all face certain engineering costs and challenges. High-frequency communication technology is limited by factors such as atmospheric rain attenuation, short propagation distance, and high power requirements, and still faces significant challenges in engineering applications.

[0007] Electrophilic material injection is difficult to implement due to its limited injection range, making it hard to penetrate the entire plasma sheath. Magnetic windowing, which uses strong electromagnetic fields to control plasma distribution, requires a large and heavy magnetic generator, severely impacting the spacecraft's payload and resulting in low practicality and economic efficiency.

[0008] In the prior art, patent number 201710049140.1 discloses a method for X-ray communication in the blackout zone during the reentry of an aircraft. X-ray communication has an absolute advantage in penetrating plasma, but due to its high directivity, the aircraft and the ground receiving end must maintain extremely high alignment accuracy.

[0009] Patent No. 202410148826.3 discloses a black barrier communication method based on gain metamaterials. This method fixes the frequency of the incident electromagnetic wave and simultaneously adjusts the dielectric constant and permeability of the matching metamaterial, which is difficult to implement. Although the matching method using a negative permeability metamaterial can improve the input wave impedance of the plasma, the plasma density is low and there are still great limitations in strong collision environments. Summary of the Invention

[0010] The purpose of this invention is to overcome the many limitations of existing blackout communication methods, including sacrificing the aerodynamic performance and flight load of aircraft, atmospheric rain attenuation, constraints of weak collision environments, and the development of communication equipment, and to provide a blackout communication method and system based on gain metamaterials.

[0011] This invention provides a black-barrier communication method based on gain metamaterials, the method being as follows:

[0012] Simulate the generation of a plasma-gain metamaterial matching system;

[0013] The matching system consists of a symmetrically and fitted plasma layer and a simulated gain metamaterial layer;

[0014] The thickness of the simulated gain metamaterial layer is equal to the thickness of the plasma layer, and the dielectric constant of the simulated gain metamaterial layer and the relative dielectric constant of the plasma layer satisfy the following equation:

[0015]

[0016] in, The simulated dielectric constant of the metamaterial layer for simulating gain; * represents the dielectric constant of the plasma layer; * indicates conjugate. This refers to any position along the thickness direction of the plasma layer or the simulated gain metamaterial layer, specifically at the interface between the plasma layer and the simulated gain metamaterial layer. ;

[0017] The frequency of the incident electromagnetic wave when the matching system is in equilibrium and stable is taken as the frequency of the communication signal.

[0018] The balanced stability of a matched system is the state in which the gain and loss of the matched system are balanced and the eigenvalue curve is closed.

[0019] When a matching system is formed between the physical gain metamaterial layer and the plasma layer at the blackout, communication is carried out through a communication signal that conforms to the communication signal frequency;

[0020] The physical gain metamaterial layer and the simulated gain metamaterial layer have the same thickness and dielectric constant.

[0021] Furthermore, assessing whether the matching system is in equilibrium and stable includes:

[0022] The two eigenvalues ​​of the matching system are obtained by calculating the scattering matrix S. and and two eigenvectors and ;

[0023] Formula 1

[0024] , Formula 2

[0025] Formula 3

[0026]

[0027] in, , , and All are scattering parameters; , Let be the transmission coefficients of the incident electromagnetic wave when it is incident from the left and right sides of the matched system, respectively, and let be the transmission coefficients when the gain and loss are balanced. ; , These are the reflection coefficients when the incident electromagnetic wave is incident from the left and right sides of the matching system, respectively.

[0028] By conserving energy, the scattering parameter relationship is obtained when gain and loss are balanced:

[0029] Formula 4

[0030] in, , , ;

[0031] Introducing the conditions for the coincidence of two eigenvalues ​​and two eigenvectors in a matching system. or Solving for ;

[0032] Substituting Formula 4 into Formula 1, we get:

[0033] Formula 5

[0034]

[0035] Solving ;

[0036] Determine whether two feature values ​​of the matching system satisfy If the eigenvalue curve is closed, the matching system is stable.

[0037] Furthermore, the communication signal is polarized by transverse magnetic polarization, and the communication signal is incident perpendicularly onto the matching system.

[0038] Furthermore, the frequency band of the communication signal is 1 GHz and above.

[0039] Furthermore, in the plasma-gain metamaterial matching system, the relative permittivity of the plasma layer... for:

[0040]

[0041] in, The plasma frequency; Let be the angular frequency of the incident electromagnetic wave. , The frequency of the incident electromagnetic wave; The symbol for the imaginary part; denoted as the plasma collision frequency.

[0042] The present invention also provides a blackout communication system based on gain metamaterials, comprising:

[0043] Matching stability assessment module for simulating matching systems of generated plasma-gain metamaterials;

[0044] The matching system consists of a symmetrically and fitted plasma layer and a simulated gain metamaterial layer;

[0045] The thickness of the simulated gain metamaterial layer is equal to the thickness of the plasma layer, and the dielectric constant of the simulated gain metamaterial layer and the relative dielectric constant of the plasma layer satisfy the following equation:

[0046]

[0047] in, The simulated dielectric constant of the metamaterial layer for simulating gain; * represents the dielectric constant of the plasma layer; * indicates conjugate. This refers to any position along the thickness direction of the plasma layer or the simulated gain metamaterial layer, specifically at the interface between the plasma layer and the simulated gain metamaterial layer. ;

[0048] In addition, it is used to evaluate whether the matching system is balanced and stable, and the incident electromagnetic wave frequency corresponding to the balanced and stable matching system is used as the communication signal frequency;

[0049] The balanced stability of a matched system is the state in which the gain and loss of the matched system are balanced and the eigenvalue curve is closed.

[0050] Gain metamaterial tuning module, used to tune the dielectric constant of the solid gain metamaterial layer to be the same as that of the analog gain metamaterial layer;

[0051] A multi-band communication module is used to communicate via communication signals that conform to the communication signal frequency when a matching system is formed between the solid gain metamaterial layer and the plasma layer at the blackout.

[0052] The thickness of the physical gain metamaterial layer is the same as the thickness of the simulated gain metamaterial layer.

[0053] Furthermore, the matching stability assessment module evaluates whether the matching system is balanced and stable in the following manner:

[0054] The two eigenvalues ​​of the matching system are obtained by calculating the scattering matrix S. and and two eigenvectors and ;

[0055] Formula 1

[0056] , Formula 2

[0057] Formula 3

[0058]

[0059] in, , , and All are scattering parameters; , Let be the transmission coefficients of the incident electromagnetic wave when it is incident from the left and right sides of the matched system, respectively, and let be the transmission coefficients when the gain and loss are balanced. ; , These are the reflection coefficients when the incident electromagnetic wave is incident from the left and right sides of the matching system, respectively.

[0060] By conserving energy, the scattering parameter relationship is obtained when gain and loss are balanced:

[0061] Formula 4

[0062] in, , , ;

[0063] Introducing the conditions for the coincidence of two eigenvalues ​​and two eigenvectors in a matching system. or Solving for ;

[0064] Substituting Formula 4 into Formula 1, we get:

[0065] Formula 5

[0066]

[0067] Solving ;

[0068] Determine whether two feature values ​​of the matching system satisfy If the eigenvalue curve is closed, the matching system is stable.

[0069] Furthermore, in the multi-band communication module, the polarization of the communication signal is transverse magnetic polarization, and the communication signal is incident perpendicularly onto the matching system.

[0070] Furthermore, the frequency band of the communication signal is 1 GHz and above.

[0071] Furthermore, it also includes a plasma parameter diagnostic module;

[0072] The plasma parameter diagnostic module is used to obtain the relative permittivity of the plasma layer in the following manner. :

[0073]

[0074] in, The plasma frequency; Let be the angular frequency of the incident electromagnetic wave. , The frequency of the incident electromagnetic wave; The symbol for the imaginary part; denoted as the plasma collision frequency.

[0075] The beneficial effects of this invention are:

[0076] This invention can alleviate the blackout communication problem of high-speed aircraft and has the following advantages:

[0077] First, there is no need to add a strong magnetic field generating device, reducing the aircraft's load and flight costs;

[0078] Second, it uses electromagnetic waves in the GHz common communication band, and the communication technology in this band is mature.

[0079] Third, by using matched metamaterials with balanced gain, the signal loss caused by high-density, high-impact plasma can be overcome simultaneously, making it suitable for high-density plasma layers.

[0080] IV. The key electromagnetic parameters of the plasma sheath depend on the state parameters of the spacecraft, such as altitude, speed, and attitude. By utilizing the tunability of metamaterials and not fixing the incident electromagnetic wave frequency, it can provide an important guarantee for reliable and effective communication throughout the flight. Attached Figure Description

[0081] Figure 1 This is a schematic diagram of the blackout communication system based on gain metamaterials of the present invention;

[0082] Figure 2 This is a schematic diagram of the plasma-gain metamaterial matching system in the black-barrier communication method and system based on gain metamaterials of the present invention; where k is the wave vector and E is the electric field.

[0083] Figure 3 The eigenvalue curves are for the matching system corresponding to Specific Embodiment 1; where σ1 and σ2 are the base-10 logarithmic values ​​of the eigenvalues ​​of the scattering matrix S.

[0084] Figure 4 The transmittance curve after matching by the matching system corresponding to Specific Embodiment 1;

[0085] Figure 5 The feature value curve of the matching system corresponding to specific embodiment 2;

[0086] Figure 6 The transmittance curve after matching by the matching system corresponding to specific embodiment 2;

[0087] Figure 7 This is a plasma density distribution diagram in the plasma layer of the matching system corresponding to specific embodiment 3.

[0088] Figure 8 The feature value curve of the matching system corresponding to specific embodiment 3;

[0089] Figure 9 The transmittance curve is the result of matching the matching system corresponding to specific embodiment 3. Detailed Implementation

[0090] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0091] It should be noted that, unless otherwise specified, the embodiments and features described in the present invention can be combined with each other.

[0092] The present invention will be further described below with reference to the accompanying drawings and specific embodiments, but this is not intended to limit the scope of the invention. Specific Implementation Method 1

[0094] The black-barrier communication method based on gain metamaterials in this embodiment is as follows:

[0095] Simulate the generation of a plasma-gain metamaterial matching system;

[0096] The matching system consists of a symmetrically and fitted plasma layer and a simulated gain metamaterial layer;

[0097] The thickness of the simulated gain metamaterial layer is equal to the thickness of the plasma layer, and the dielectric constant of the simulated gain metamaterial layer and the relative dielectric constant of the plasma layer satisfy the following equation:

[0098]

[0099] in, The simulated dielectric constant of the metamaterial layer for simulating gain; * represents the dielectric constant of the plasma layer; * indicates conjugate. This refers to any position along the thickness direction of the plasma layer or the simulated gain metamaterial layer, specifically at the interface between the plasma layer and the simulated gain metamaterial layer. ;

[0100] The frequency of the incident electromagnetic wave when the matching system is in equilibrium and stable is taken as the frequency of the communication signal.

[0101] The balanced stability of a matched system is the state in which the gain and loss of the matched system are balanced and the eigenvalue curve is closed.

[0102] When a matching system is formed between the physical gain metamaterial layer and the plasma layer at the blackout, communication is carried out through a communication signal that conforms to the communication signal frequency;

[0103] The physical gain metamaterial layer and the simulated gain metamaterial layer have the same thickness and dielectric constant.

[0104] Specifically, this invention provides a signal loss compensation scheme based on gain metamaterials. By constructing a metamaterial-plasma bilayer structure that balances gain and loss, the transmission rate of electromagnetic waves (GHz band) in dense, strongly impacting plasma can be effectively improved.

[0105] The specific steps are as follows:

[0106] Step 1: On the ground, the plasma parameter diagnostic module is used to simulate and predict typical blackout plasma layer environments (plasma sheaths) at different altitudes.

[0107] Step 2: Simulate the metamaterial with balanced gain using the matching stability assessment module to assess the matching stability of the metamaterial-plasma system:

[0108] Stability assessment of a plasma-gain metamaterial matched system. A metamaterial with a simulated equilibrium gain level is used, its gain characteristics characterized by the imaginary part of its dielectric constant. The gain level of the metamaterial is comparable to the loss level of the plasma, and its dielectric constant ε² can be expressed as:

[0109] ε2(x)=ε p * (-x)

[0110] In the formula, * indicates taking the conjugate.

[0111] like Figure 2 As shown, a plasma layer and a gain metamaterial layer, both with a thickness of d, are placed side by side. The relative permittivity and relative permeability of the plasma layer and the gain metamaterial layer are respectively (ε... p μ p =1) and (ε2, μ2=1), with vacuum on both sides. A TM (Transverse Magnetic Field) polarized electromagnetic wave is incident obliquely on the double-layer structure from the left or right, with a frequency of f and an incident angle of θ.

[0112] Step 3: Form a solid metamaterial with a balanced gain level. The thickness of the solid metamaterial is consistent with that of the plasma. The dielectric constant of the metamaterial can be determined according to the selected communication wave frequency, and then adjusted to the corresponding value through the gain metamaterial tuning module.

[0113] Step 4: Transmit the corresponding communication signal. Specific Implementation Method Two

[0115] This embodiment is a further explanation of embodiment one. In this embodiment, evaluating whether the matching system is balanced and stable includes:

[0116] The two eigenvalues ​​of the matching system are obtained by calculating the scattering matrix S. and and two eigenvectors and ;

[0117] Formula 1

[0118] , Formula 2

[0119] Formula 3

[0120]

[0121] in, , , and All are scattering parameters; , Let be the transmission coefficients of the incident electromagnetic wave when it is incident from the left and right sides of the matched system, respectively, and let be the transmission coefficients when the gain and loss are balanced. ; , These are the reflection coefficients when the incident electromagnetic wave is incident from the left and right sides of the matching system, respectively.

[0122] By conserving energy, the scattering parameter relationship is obtained when gain and loss are balanced:

[0123] Formula 4

[0124] in, , , ;

[0125] Introducing the conditions for the coincidence of two eigenvalues ​​and two eigenvectors in a matching system. or Solving for ;

[0126] Substituting Formula 4 into Formula 1, we get:

[0127] Formula 5

[0128]

[0129] Solving ;

[0130] Determine whether two feature values ​​of the matching system satisfy If the eigenvalue curve is closed, the matching system is stable.

[0131] The other technical features of this embodiment are exactly the same as those of Embodiment 1.

[0132] Specifically, the evaluation process in step 2 of Example 1 is as follows:

[0133] The matching stability of the plasma-metamaterial system is described by the scattering matrix S:

[0134]

[0135] In the formula, r in the diagonal component L and r R These represent the reflection coefficients when the electromagnetic wave is incident from the left and right sides, respectively, with t in the off-diagonal component. Land t R These represent the transmission coefficients when electromagnetic waves are incident from the left and right sides, respectively. In the equilibrium system, t=t L =t R .

[0136] Solving for the eigenvalues ​​of the scattering matrix S in the equation allows us to analyze the singularity condition where the eigenvalues ​​and eigenvectors coincide, revealing anomalous scattering phenomena. The eigenvalues ​​of the scattering matrix can be obtained from the above equation. and and eigenvectors and for

[0137] Formula 1

[0138] , Formula 2

[0139] Formula 3

[0140]

[0141] According to the above formula, when r L =0 or r R When = 0, the eigenvalues ​​and eigenvectors coincide, forming a singularity. At this point, the system exhibits anisotropic transmission, meaning unidirectional non-reflection. If the system's gain and loss are balanced, the scattering parameters have the following relationship:

[0142]

[0143] Among them, R L =|r L | 2 R R =|r R | 2 T=|t| 2 The eigenvalues ​​of the scattering parameters can then be further expressed as:

[0144] ,

[0145] From this, we can derive the condition for the formation of singularities as T=1, at which point the system exhibits bidirectional total transmission (T=1) and unidirectional non-reflection (r). L =0 or r R =0) behavior. We can also obtain |λ1λ2|=1. When λ1=λ2=1, the characteristic frequency is a real number, and the system remains in equilibrium and stable. Conversely, when λ1=1 / λ2, the system equilibrium is disrupted, the characteristic frequency has an imaginary part, and the matched system cannot exist stably.

[0146] In summary, the stability of the gain metamaterial-plasma matching system can be determined from the eigenvalue distribution of the scattering matrix S. For a given matching system, as the incident wave frequency increases, the system's eigenvalue curve gradually closes, indicating that the matching system tends to stabilize. Therefore, the communication wave frequency corresponding to the system's stability should be selected. Specific Implementation Method 3

[0148] This embodiment is a further explanation of embodiment one or two. In step four of this embodiment:

[0149] The communication signal is polarized by transverse magnetic polarization and is incident perpendicularly onto the matching system.

[0150] The other technical features of this embodiment are exactly the same as those of Embodiment 1 or 2.

[0151] Specifically, in step 4 of the first implementation method, the polarization mode of the communication signal is transverse magnetic polarization, and the electromagnetic wave is perpendicularly irradiated on the metamaterial-plasma double-layer structure. Specific Implementation Method Four

[0153] This embodiment is a further explanation of embodiment three. In this embodiment, the frequency band of the communication signal is 1GHz and above.

[0154] The other technical features of this embodiment are exactly the same as those of Embodiment 3. Detailed Implementation Method Five

[0156] This embodiment is a further explanation of Embodiment 1, 2, or 4. In the plasma-gain metamaterial matching system of this embodiment, the relative permittivity of the plasma layer is... for:

[0157]

[0158] in, The plasma frequency; Let be the angular frequency of the incident electromagnetic wave. , The frequency of the incident electromagnetic wave; The symbol for the imaginary part; denoted as the plasma collision frequency.

[0159] The other technical features of this embodiment are exactly the same as those of Embodiment 1, 2 or 4.

[0160] Specifically, in step 1 of embodiment 1, the plasma parameter diagnosis module acquires the characteristic parameters of the plasma (thickness, electron density, and collision frequency) and predicts the parameters of the plasma sheath (plasma layer).

[0161] The characteristic parameters of the plasma sheath, including thickness, electron density, and collision frequency, are obtained. Here, the dielectric constant of the plasma is generally described by the Drude model, with its relative dielectric constant ε... p It can be represented as:

[0162]

[0163] In the formula ω pe Let be the plasma frequency, and its expression is: n e Let be the electron density of the plasma, e be the unit charge, ε0 be the relative permittivity in vacuum, and m be the electron density of the plasma. e Let ω be the electron mass, ω be the angular frequency of the incident wave (ω=2πf), and v be the plasma collision frequency. Specific Implementation Method Six

[0165] The blackout communication system based on gain metamaterials in this embodiment includes:

[0166] Matching stability assessment module for simulating matching systems of generated plasma-gain metamaterials;

[0167] The matching system consists of a symmetrically and fitted plasma layer and a simulated gain metamaterial layer;

[0168] The thickness of the simulated gain metamaterial layer is equal to the thickness of the plasma layer, and the dielectric constant of the simulated gain metamaterial layer and the relative dielectric constant of the plasma layer satisfy the following equation:

[0169]

[0170] in, The simulated dielectric constant of the metamaterial layer for simulating gain; * represents the dielectric constant of the plasma layer; * indicates conjugate. This refers to any position along the thickness direction of the plasma layer or the simulated gain metamaterial layer, specifically at the interface between the plasma layer and the simulated gain metamaterial layer. ;

[0171] In addition, it is used to evaluate whether the matching system is balanced and stable, and the incident electromagnetic wave frequency corresponding to the balanced and stable matching system is used as the communication signal frequency;

[0172] The balanced stability of a matched system is the state in which the gain and loss of the matched system are balanced and the eigenvalue curve is closed.

[0173] Gain metamaterial tuning module, used to tune the dielectric constant of the solid gain metamaterial layer to be the same as that of the analog gain metamaterial layer;

[0174] A multi-band communication module is used to communicate via communication signals that conform to the communication signal frequency when a matching system is formed between the solid gain metamaterial layer and the plasma layer at the blackout.

[0175] The thickness of the physical gain metamaterial layer is the same as the thickness of the simulated gain metamaterial layer. Detailed Implementation Method Seven

[0177] This embodiment is a further explanation of embodiment six. In this embodiment, the matching stability evaluation module evaluates whether the matching system is balanced and stable in the following way:

[0178] The two eigenvalues ​​of the matching system are obtained by calculating the scattering matrix S. and and two eigenvectors and ;

[0179] Formula 1

[0180] , Formula 2

[0181] Formula 3

[0182]

[0183] in, , , and All are scattering parameters; , Let be the transmission coefficients of the incident electromagnetic wave when it is incident from the left and right sides of the matched system, respectively, and let be the transmission coefficients when the gain and loss are balanced. ; , These are the reflection coefficients when the incident electromagnetic wave is incident from the left and right sides of the matching system, respectively.

[0184] By conserving energy, the scattering parameter relationship is obtained when gain and loss are balanced:

[0185] Formula 4

[0186] in, , , ;

[0187] Introducing the conditions for the coincidence of two eigenvalues ​​and two eigenvectors in a matching system. or Solving for ;

[0188] Substituting Formula 4 into Formula 1, we get:

[0189] Formula 5

[0190]

[0191] Solving ;

[0192] Determine whether two feature values ​​of the matching system satisfy If the eigenvalue curve is closed, the matching system is stable.

[0193] The other technical features of this embodiment are exactly the same as those of Embodiment Six. Detailed Implementation Method Eight

[0195] This embodiment is a further explanation of embodiment six or seven. In this embodiment, the polarization mode of the communication signal in the multi-band communication module is transverse magnetic polarization, and the communication signal is incident perpendicularly to the matching system.

[0196] The other technical features of this embodiment are exactly the same as those of embodiment six or seven. Detailed Implementation Method Nine

[0198] This embodiment is a further explanation of embodiment eight. In this embodiment, the frequency band of the communication signal is 1 GHz and above.

[0199] The other technical features of this embodiment are exactly the same as those of embodiment eight. Detailed Implementation Method Ten

[0201] This embodiment is a further description of embodiment six, seven or nine. In this embodiment, a plasma parameter diagnosis module is also included.

[0202] The plasma parameter diagnostic module is used to obtain the relative permittivity of the plasma layer in the following manner. :

[0203]

[0204] in, The plasma frequency; Let be the angular frequency of the incident electromagnetic wave. , The frequency of the incident electromagnetic wave; The symbol for the imaginary part; denoted as the plasma collision frequency.

[0205] The other technical features of this embodiment are exactly the same as those of embodiments six, seven, or nine.

[0206] The specific embodiments formed according to the present invention are as follows:

[0207] Specific Implementation Example 1: The placement method of plasma and gain metamaterial is as follows Figure 2 As shown. The plasma is uniformly distributed with a density n. e =1e18m -3 The collision frequency υ = 10 GHz, the thickness of both the plasma and the gain metamaterial is 10 cm, the plasma and metamaterial are placed side by side and closely, and electromagnetic waves are irradiated onto the double-layer structure from the left perpendicularly. Figure 3 As shown, the eigenvalues ​​of the matched system change with the incident wave frequency. As the incident wave frequency increases, the eigenvalues ​​change from bifurcated to closed-loop, and the system's stability critical frequency is 12.53 GHz. Figure 4 As shown, when the incident wave frequency is greater than 13.95 GHz, electromagnetic waves can completely pass through the plasma-metamaterial matching system.

[0208] Specific Implementation Example 2: The placement method of plasma and gain metamaterial is as follows Figure 2 As shown. The plasma is uniformly distributed with a density n. e =1e19m -3 The collision frequency υ = 10 GHz, the thickness of both the plasma and the gain metamaterial is 10 cm, the plasma and metamaterial are placed side by side and closely, and electromagnetic waves are irradiated onto the double-layer structure from the left perpendicularly. Figure 5 As shown, the eigenvalues ​​of the matched system change with the incident wave frequency. As the incident wave frequency increases, the eigenvalues ​​change from bifurcated to closed-loop, and the system's stability critical frequency is 41.54 GHz. Figure 6 As shown, when the incident wave frequency is greater than 43.56 GHz, electromagnetic waves can completely pass through the plasma-metamaterial matching system.

[0209] Specific Implementation Example 3: The placement method of plasma and gain metamaterial is as follows Figure 2 As shown. The plasma is non-uniformly distributed, and its density distribution is as follows. Figure 7 As shown, the collision frequency υ = 10 GHz, the thickness of both the plasma and the gain metamaterial is 10 cm, the plasma and metamaterial are placed side by side and closely, and electromagnetic waves are irradiated onto the double-layer structure from the left perpendicularly. Figure 8 As shown, the eigenvalues ​​of the matched system change with the incident wave frequency. As the incident wave frequency increases, the eigenvalues ​​change from bifurcated to closed-loop, and the system's stability critical frequency is 30.34 GHz. Figure 9 As shown, when the incident wave frequency is greater than 31.36 GHz, electromagnetic waves can completely pass through the plasma-metamaterial matching system.

Claims

1. A black-barrier communication method based on gain metamaterials, characterized in that, The method is as follows: Simulate the generation of a plasma-gain metamaterial matching system; The matching system includes a symmetrically and fitted plasma layer and a simulated gain metamaterial layer; The thickness of the simulated gain metamaterial layer is equal to the thickness of the plasma layer, and the dielectric constant of the simulated gain metamaterial layer and the relative dielectric constant of the plasma layer satisfy the following equation: in, The simulated dielectric constant of the metamaterial layer for simulating gain; * represents the dielectric constant of the plasma layer; * indicates conjugate. This refers to any position along the thickness direction of the plasma layer or the simulated gain metamaterial layer, specifically at the interface between the plasma layer and the simulated gain metamaterial layer. ; The frequency of the incident electromagnetic wave when the matching system is in equilibrium and stable is taken as the frequency of the communication signal. The matching system is considered to be in a state where the gain and loss of the matching system are balanced and the eigenvalue curve is closed. When the structure of the matching system is formed in the plasma layer at the solid gain metamaterial layer and the blackout layer, communication is carried out through a communication signal that conforms to the frequency of the communication signal. The physical gain metamaterial layer and the simulated gain metamaterial layer have the same thickness and dielectric constant.

2. The black-barrier communication method based on gain metamaterials according to claim 1, characterized in that, Assessing whether the matching system is balanced and stable includes: The two eigenvalues ​​of the matching system are calculated using the scattering matrix S. and and two eigenvectors and ; Formula 1 , Formula 2 Formula 3 in, , , and All are scattering parameters; , These are the transmission coefficients when the incident electromagnetic wave is incident from the left and right sides of the matched system, respectively, and when gain and loss are balanced. ; , These are the reflection coefficients when the incident electromagnetic wave is incident from the left and right sides of the matching system, respectively. By conserving energy, the scattering parameter relationship is obtained when gain and loss are balanced: Formula 4 in, , , ; Introducing the conditions for the coincidence of two eigenvalues ​​and two eigenvectors in a matching system. or Solving for ; Substituting Formula 4 into Formula 1, we get: Formula 5 Solving ; Determine whether the two feature values ​​of the matching system satisfy the following conditions. If the eigenvalue curve is closed, the matching system is stable.

3. The black-barrier communication method based on gain metamaterials according to claim 1 or 2, characterized in that, The communication signal is polarized by transverse magnetic polarization, and the communication signal is incident perpendicularly onto the matching system.

4. The black-barrier communication method based on gain metamaterials according to claim 3, characterized in that, The frequency band of the communication signal is 1 GHz and above.

5. The black-barrier communication method based on gain metamaterials according to claim 1, 2, or 4, characterized in that, In a plasma-gain metamaterial matching system, the relative permittivity of the plasma layer for: in, The plasma frequency; Let be the angular frequency of the incident electromagnetic wave. , The frequency of the incident electromagnetic wave; The symbol for the imaginary part; denoted as the plasma collision frequency.

6. A blackout communication system based on gain metamaterials, characterized in that, include: Matching stability assessment module for simulating matching systems of generated plasma-gain metamaterials; The matching system includes a symmetrically and fitted plasma layer and a simulated gain metamaterial layer; The thickness of the simulated gain metamaterial layer is equal to the thickness of the plasma layer, and the dielectric constant of the simulated gain metamaterial layer and the relative dielectric constant of the plasma layer satisfy the following equation: in, The simulated dielectric constant of the metamaterial layer for simulating gain; * represents the dielectric constant of the plasma layer; * indicates conjugate. This refers to any position along the thickness direction of the plasma layer or the simulated gain metamaterial layer, specifically at the interface between the plasma layer and the simulated gain metamaterial layer. ; In addition, it is used to evaluate whether the matching system is balanced and stable, and to use the incident electromagnetic wave frequency corresponding to the balanced and stable matching system as the communication signal frequency; The matching system is considered to be in a state where the gain and loss of the matching system are balanced and the eigenvalue curve is closed. Gain metamaterial tuning module, used to tune the dielectric constant of the solid gain metamaterial layer to be the same as that of the analog gain metamaterial layer; A multi-band communication module is used to communicate via a communication signal that conforms to the frequency of the communication signal when the structure of the matching system is formed in the plasma layer at the solid gain metamaterial layer and the blackout layer. The thickness of the physical gain metamaterial layer is the same as the thickness of the simulated gain metamaterial layer.

7. The black-barrier communication system based on gain metamaterials according to claim 6, characterized in that, The matching stability assessment module evaluates whether the matching system is balanced and stable in the following manner: The two eigenvalues ​​of the matching system are calculated using the scattering matrix S. and and two eigenvectors ; Formula 1 , Formula 2 Formula 3 in, , , and All are scattering parameters; , These are the transmission coefficients when the incident electromagnetic wave is incident from the left and right sides of the matched system, respectively, and when gain and loss are balanced. ; , These are the reflection coefficients when the incident electromagnetic wave is incident from the left and right sides of the matching system, respectively. By conserving energy, the scattering parameter relationship is obtained when gain and loss are balanced: Formula 4 in, , , ; Introducing the conditions for the coincidence of two eigenvalues ​​and two eigenvectors in a matching system. or Solving for ; Substituting Formula 4 into Formula 1, we get: Formula 5 Solving ; Determine whether the two feature values ​​of the matching system satisfy the following conditions. If the eigenvalue curve is closed, the matching system is stable.

8. The blackout communication system based on gain metamaterials according to claim 6 or 7, characterized in that, In the multi-band communication module, the communication signal is polarized by transverse magnetic polarization, and the communication signal is incident perpendicularly onto the matching system.

9. The blackout communication system based on gain metamaterials according to claim 8, characterized in that, The frequency band of the communication signal is 1 GHz and above.

10. The blackout communication system based on gain metamaterials according to claim 6, 7, or 9, characterized in that, It also includes a plasma parameter diagnostic module; The plasma parameter diagnostic module is used to obtain the relative permittivity of the plasma layer in the following manner. : in, The plasma frequency; Let be the angular frequency of the incident electromagnetic wave. , The frequency of the incident electromagnetic wave; The symbol for the imaginary part; denoted as the plasma collision frequency.

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