Search

CN-121995122-A - Dynamic electromagnetic reverberation chamber based on plasma regulation and control method thereof

CN121995122ACN 121995122 ACN121995122 ACN 121995122ACN-121995122-A

Abstract

The invention discloses a dynamic electromagnetic reverberation chamber based on plasma regulation and control and a control method thereof, which belong to the technical field of electromagnetic testing, wherein a plasma array module and a driving control module are arranged on the inner wall surface of a cavity of the reverberation chamber, and the electron density and the collision frequency of the reverberation chamber are changed by regulating the discharge parameters of a plasma unit in real time, so that the equivalent quality factor Q value, the normalized field intensity and the energy attenuation time constant of the reverberation chamber are dynamically and continuously regulated and controlled.

Inventors

  • JIA RUI
  • LI XINFENG
  • Geng Lifei
  • GUO HAO

Assignees

  • 中国人民解放军63892部队

Dates

Publication Date
20260508
Application Date
20251224

Claims (8)

  1. 1. The dynamic electromagnetic reverberation chamber based on plasma regulation and control comprises a reverberation chamber body, a plasma array module, a driving control module and a feedback monitoring module, and is characterized in that the plasma array module is embedded into the six inner walls of the reverberation chamber body, the driving control module is electrically connected with the plasma array module, and the equivalent quality factor Q value of the reverberation chamber is dynamically regulated; the plasma array module is formed by arranging a plurality of plasma units in a honeycomb shape, and the plasma electron density and the collision frequency are controlled by adjusting the driving voltage and the pulse frequency so as to change the equivalent electromagnetic parameters; The driving control module comprises a high-voltage pulse generator and a partition control logic unit, wherein the driving control module is used for outputting pulse signals with adjustable parameters and realizing the partition independent control of the plasma array; the feedback monitoring module comprises a broadband electric field probe array and a self-adaptive control unit and is used for collecting field intensity data in the cavity in real time and generating parameter adjustment instructions to realize closed-loop regulation and control.
  2. 2. The dynamic electromagnetic reverberation chamber based on plasma regulation and control according to claim 1, wherein the plasma units adopt a dielectric barrier discharge structure or a radio frequency driving ionization source, each unit comprises two layers of metal electrodes, the two layers of metal electrodes are provided with middle dielectric layers, the thickness of the metal electrodes of the plasma units is 0.1mm, the middle dielectric layers are Al 2 O 3 ceramic or PVC thin films, the thickness is 1mm, the size of the plasma units is 10cm x 10cm, the distance between two adjacent plasma units is 1/8 to 1/4 of the lowest frequency wavelength of the working frequency band, and the range of the electron density n e is controlled to be 10 9 -10 12 cm -3 and the range of the collision frequency v c is 10 8 -10 11 Hz by regulating driving parameters.
  3. 3. The dynamic electromagnetic reverberation chamber based on plasma regulation and control according to claim 1, wherein the high-voltage pulse generator of the driving control module adopts a full-bridge inversion topology, the output driving voltage range is 0-10kV, the pulse frequency range is 1kHz-10MHz, and the partition control logic unit divides the plasma array module into a plurality of independent control areas and supports the working mode switching of a global mode and a gradient mode.
  4. 4. The dynamic electromagnetic reverberation chamber based on plasma regulation according to claim 1, wherein the broadband electric field probe array of the feedback monitoring module is composed of a plurality of broadband electric field probes which are equally spaced inside the reverberation chamber body, the frequency range is 100MHz-20GHz, the self-adaptive algorithm unit generates a plasma parameter adjustment instruction based on least square fitting field intensity data, closed-loop control is realized, and the response time of the closed-loop control is <10ms.
  5. 5. The dynamic electromagnetic reverberation chamber based on plasma regulation according to claim 1, wherein the reverberation chamber has three modes of operation: The total reflection high Q mode is to turn off all plasma units, the wall surface of the reverberation chamber body is equivalent to the full metal surface, the Q value is determined by the inherent loss of the reverberation chamber body, Q is more than 50,000, and the method is suitable for high-sensitivity receiver test and weak electromagnetic signal detection scenes The full absorption low Q mode is that high-frequency >5MHz and high-voltage pulse >8kV are applied to all plasma units, so that omega p is obviously higher than the working frequency, and the Q value is reduced to 200-500; And (3) a gradient loss mode, namely independently controlling plasma parameters of different wall surface areas to form non-uniform field distribution in a reverberation chamber body, optimizing field uniformity of a specific area, and ensuring that the standard deviation of field intensity is less than 1dB.
  6. 6. The dynamic electromagnetic reverberation chamber based on plasma regulation according to claim 1, wherein the plasma layer thickness formed by the plasma array module is 3-5cm, and the power consumption in the activated state is <200W/m2.
  7. 7. A control method for controlling a dynamic electromagnetic reverberation chamber based on plasma regulation according to any one of claims 1 to 6, comprising: The system initialization, namely completing the connection and calibration of the plasma array, the driving control module and the feedback monitoring module, and determining initial working parameters; Target parameter input, namely setting a target quality factor, normalized field intensity and energy attenuation time constant of the electromagnetic reverberation chamber according to test requirements; the plasma parameter regulation and control, namely, a driving control module outputs a pulse signal according to a target parameter, adjusts the electron density and the collision frequency of the plasma, and changes the equivalent dielectric constant and the conductivity of the plasma; And (3) closed loop optimization, namely collecting field intensity data in real time by a feedback monitoring module, generating an adjustment instruction through a self-adaptive algorithm, and dynamically correcting the working parameters of the plasma until reaching a target value.
  8. 8. The method of claim 7, wherein during the plasma parameter adjustment, the Q value is dynamically adjusted by switching the plasma operating state: The equivalent relative permittivity of the plasma is expressed as: , Wherein omega p is the plasma frequency, omega is the angular frequency of the incident electromagnetic wave, Is electron collision frequency; the plasma frequency is determined by , In the formula, For the amount of electron charge, Is a dielectric constant of a vacuum and is a dielectric constant, For the quality of the electrons, Is electron density; Different working states are realized through the relation between the plasma frequency omega p and the incident electromagnetic wave angular frequency omega: When the plasma frequency omega p is less than the incident electromagnetic wave angular frequency omega, the plasma has low-loss dielectric property, the electromagnetic wave is partially reflected, the Q value of the cavity is determined by the inherent loss, and Q is more than 50,000; when the plasma frequency omega p is higher than the incident electromagnetic wave angular frequency omega, the plasma has high-loss dielectric property, electromagnetic wave energy is collisional and dissipated into heat energy, the Q value is obviously reduced, and the Q value is reduced to a range of 200-500; By adjusting the driving voltage and the frequency, the Q value can be controlled and adjusted continuously, and the calculation formula of the effective Q value of the cavity is as follows: , Wherein U stored is the cavity stored energy representing the total amount of electromagnetic energy stored in the cavity, P loss_plasma is the plasma loss power representing the rate at which the plasma absorbs and consumes electromagnetic energy, and P loss_cavity is the cavity inherent loss power reflecting the inevitable energy loss of the cavity itself.

Description

Dynamic electromagnetic reverberation chamber based on plasma regulation and control method thereof Technical Field The invention relates to the technical field of electromagnetic testing, in particular to a dynamic electromagnetic reverberation chamber based on plasma regulation and control and a control method thereof. Background The electromagnetic reverberation chamber is test equipment capable of generating a statistically uniform isotropic electromagnetic field environment, and is widely applied to the fields of electromagnetic compatibility test, antenna efficiency measurement, material electromagnetic characteristic research and the like. The traditional reverberation chamber changes the cavity modal distribution mainly by rotating metal blades or frequency tuning through a mechanical stirrer, thereby realizing field homogenization. However, the conventional reverberation room has inherent technical limitations that, firstly, the Q value of the quality factor is mainly determined by the cavity structure, metal wall loss and fixed wave absorbing material, and once the construction is completed, the quality factor is difficult to dynamically adjust, and the requirements of different test scenes such as weak signal detection with high Q value, rapid energy attenuation with low Q value and the like cannot be flexibly met. Secondly, mechanical agitators have problems of slow response speed, typically greater than 100ms, large occupied space in the cavity, typically exceeding 15% volume, etc., limiting test efficiency and layout flexibility. Finally, the frequency tuning method can only realize high field intensity at discrete resonance frequency points, and is difficult to meet the requirement of broadband continuous test. The plasma is used as a fourth state of the substance, and the equivalent dielectric constant and the electric conductivity of the plasma can be dynamically regulated through discharge parameters such as voltage and frequency, so that the flexible control of electromagnetic wave reflection and absorption characteristics is realized. At present, a plasma technology is applied to the fields of radar stealth, communication filtering and the like, but a public scheme for combining the plasma technology with a reverberation chamber to realize dynamic regulation of electromagnetic parameters of a cavity is not yet seen. Therefore, developing a novel reverberation room capable of dynamically, rapidly and continuously adjusting key electromagnetic parameters is a technical problem to be solved in the art. Disclosure of Invention The invention aims to overcome the defects in the prior art and provide a dynamic electromagnetic reverberation chamber based on plasma regulation and control and a control method thereof, wherein a plasma unit is embedded into the wall surface of the reverberation chamber, and the reflection/absorption characteristics of the plasma unit on electromagnetic waves are changed by adjusting plasma discharge parameters in real time, so that the dynamic control of the Q value, normalized field intensity and time constant of a chamber is realized. The invention aims to realize the aim, and adopts the following technical scheme that the dynamic electromagnetic reverberation chamber based on plasma regulation comprises a reverberation chamber body, a plasma array module, a driving control module and a feedback monitoring module, wherein the plasma array module is embedded into the six inner walls of the reverberation chamber body, the driving control module is electrically connected with the plasma array module, and the equivalent quality factor Q value of the reverberation chamber is dynamically regulated; the plasma array module is formed by arranging a plurality of plasma units in a honeycomb shape, and the plasma electron density and the collision frequency are controlled by adjusting the driving voltage and the pulse frequency so as to change the equivalent electromagnetic parameters; The driving control module comprises a high-voltage pulse generator and a partition control logic unit, wherein the driving control module is used for outputting pulse signals with adjustable parameters and realizing the partition independent control of the plasma array; the feedback monitoring module comprises a broadband electric field probe array and a self-adaptive control unit and is used for collecting field intensity data in the cavity in real time and generating parameter adjustment instructions to realize closed-loop regulation and control. Further, the plasma units adopt dielectric barrier discharge structures or radio frequency driving ionization sources, each unit comprises two layers of metal electrodes, the two layers of metal electrodes are provided with middle dielectric layers, the thickness of the metal electrodes of the plasma units is 0.1mm, the middle dielectric layers are Al 2O3 ceramic or PVC films, the thickness of the metal electrodes is 1mm, the size of each plasma u