Application of frequency selector in audio shielding box chamber

Abstract

The invention relates to an application of a frequency selector in an audio shielding box chamber, which comprises a box body, and is characterized in that the box body comprises coamings, and the space / periphery of the coamings is filled with a medium; comprising an interface connector, and an etching groove or a patch is arranged on the coaming; the invention provides a solution for integrating a frequency selector in an audio shielding box. According to the scheme, the adjustable frequency selector is integrated in the shielding box chamber, so that the test equipment can selectively process and analyze specific frequency signals, and the test accuracy and reliability are remarkably improved. Through the integrated design, the test system is simplified, the cost is reduced, and the overall performance of the system is enhanced.

Description

Technical Field

[0001] The invention belongs to the technical field of audio shielding, and in particular relates to the application of a frequency selector in an audio shielding box. Background Art

[0002] In the field of modern audio testing, audio shielding chambers are widely used to isolate external noise to ensure the accuracy of audio equipment testing. However, existing audio shielding chambers usually only have simple physical sound insulation functions and lack effective solutions for frequency selection and signal processing. Since signals of different frequencies have different characteristics in audio equipment testing, it is particularly important to selectively process and analyze certain frequencies. Summary of the invention

[0003] The purpose of this section is to summarize some aspects of embodiments of the present invention and briefly introduce some preferred embodiments. Some simplifications or omissions may be made in this section and the specification abstract and the invention title of this application to avoid blurring the purpose of this section, the specification abstract and the invention title, and such simplifications or omissions cannot be used to limit the scope of the present invention.

[0004] In view of the following technical problems existing in the prior art: the prior art has the problems of high loss and low selectivity.

[0005] In order to solve the above technical problems, the present invention provides the following technical solutions:

[0006] An application of a frequency selector in an audio shielding chamber, comprising:

[0007] The box body comprises enclosures, and a medium is filled between / around the enclosures; and an interface connector, wherein the enclosures are provided with etching grooves or patches.

[0008] As a preferred solution for the application of the frequency selector of the present invention in an audio shielding box, the etching groove or patch is square, circular, annular, rectangular or cross-shaped.

[0009] As a preferred solution for the application of the frequency selector of the present invention in an audio shielding box, the size of the circular patch is set to:

[0010]

[0011] Where: v is the speed of sound in the medium, which is related to the medium density and Young's modulus, ∈ r is the relative dielectric constant of the dielectric substrate, r is the radius of the circular patch, 1.841 is the zero point of the first root Bessel function, and f r is the operating frequency.

[0012] As a preferred solution for the application of the frequency selector of the present invention in an audio shielding box, the size of the rectangular patch can be

[0013]

[0014] Where: v is the speed of sound in the medium, which is related to the medium density and Young's modulus, ∈ r is the relative dielectric constant of the dielectric substrate, f r is the operating frequency, L and W are the length and width of the rectangular patch, respectively, and m and n are integers of the resonant mode.

[0015] As a preferred solution for the application of the frequency selector of the present invention in an audio shielding box, the size of the square patch can be

[0016]

[0017] a is the side length of the square patch or etched groove, v is the speed of sound in the medium, which is related to the medium density and Young's modulus, and f r is the operating frequency.

[0018] As a preferred solution for the application of the frequency selector of the present invention in an audio shielding box, the size of the rectangular ring etching groove can be:

[0019]

[0020] Where: v is the speed of sound in the medium, which is related to the medium density and Young's modulus, f r is the operating frequency

[0021] L avg is the average radius of the rectangular ring excavation, defined as (L in +L out ) / 2, where L in and L out are the inner and outer radius of the ring respectively.

[0022] As a preferred solution for the application of the frequency selector of the present invention in an audio shielding box, the size of the circular etching groove or patch can be:

[0023]

[0024] r avg is the average radius of the circular undercut or patch, defined as (r in +r out ) / 2, where r in and r out are the inner and outer radius of the ring respectively.

[0025] As a preferred solution for the application of the frequency selector of the present invention in an audio shielding box, the size of the cross-shaped etching groove is set, and the lengths of the four arms are defined as l1, l2, l3 and l4 respectively. For each arm, its corresponding resonant frequency f can be calculated respectively. 0i (i=1, 2, 3, 4), when the substrate dielectric constant and arm width are the same:

[0026]

[0027] where v is the speed of sound.

[0028] Beneficial effects of the invention: The invention proposes a solution for integrating a frequency selector in an audio shielding chamber. By integrating an adjustable frequency selector in the shielding chamber, the solution enables the test equipment to selectively process and analyze specific frequency signals, significantly improving the accuracy and reliability of the test. Through this integrated design, the test system is simplified and the overall performance of the system is enhanced. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for describing the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative labor. Among them:

[0030] Figure 1 This is a schematic diagram of a structure in which the frequency selective surface in the present invention is circular;

[0031] Figure 2 It is a schematic diagram of the structure in which the frequency selective surface in the present invention is a rectangle;

[0032] Figure 3 It is a schematic diagram of the structure in which the frequency selective surface in the present invention is cross-shaped;

[0033] Figure 4 It is a schematic diagram of the structure of the double-sided frequency selective surface in the present invention. DETAILED DESCRIPTION

[0034] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the specific implementation methods of the present invention are described in detail below in conjunction with the accompanying drawings.

[0035] In the following description, many specific details are set forth to facilitate a full understanding of the present invention, but the present invention may also be implemented in other ways different from those described herein, and those skilled in the art may make similar generalizations without violating the connotation of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0036] Secondly, the term "one embodiment" or "embodiment" as used herein refers to a specific feature, structure, or characteristic that may be included in at least one implementation of the present invention. The term "in one embodiment" that appears in different places in this specification does not necessarily refer to the same embodiment, nor does it refer to a separate or selective embodiment that is mutually exclusive with other embodiments.

[0037] Secondly, the present invention is described in detail with reference to the schematic diagram. When describing the embodiments of the present invention in detail, for the sake of convenience, the cross-sectional diagrams showing the device structure will not be partially enlarged according to the general scale, and the schematic diagrams are only examples, which should not limit the scope of protection of the present invention. In addition, in actual production, the three-dimensional dimensions of length, width and depth should be included.

[0038] Example 1

[0039] Reference Figures 1 to 4 This embodiment provides an application of a frequency selector in an audio shielding box, including:

[0040] The box body comprises enclosures, and a medium is filled between / around the enclosures; and an interface connector, wherein the enclosures are provided with etching grooves or patches.

[0041] The etching groove or patch is square, circular, annular or cross-shaped or a combination thereof.

[0042] By using different types of FSS units / combinations as the isolation box walls of the shielding box (room), various transmission and reflection characteristics can be customized to meet the signal attenuation requirements of the shielding box (room) at single / multiple frequency points and within the frequency range (bandwidth); compared with traditional shielding boxes (rooms), FSS can achieve a lightweight design, suitable for applications with restrictions on equipment size and weight; it can be customized according to the frequency requirements and space limitations of specific applications, providing a more flexible solution.

[0043] In shielded equipment, FSS can be used as the surface of doors and windows to ensure communication and visual transmission within the frequency range.

[0044] In shielding devices, it can be combined with other damping layers / absorbent material patches to quickly achieve frequency-selective sound wave attenuation and fine-tuning of the frequency bandwidth.

[0045] Furthermore, the main purpose of sound insulation and shielding is to prevent the transmission of sound waves within a specific frequency range. Different materials can be used to make FSS according to different usage scenarios. The specific evaluation factors include:

[0046] Acoustic impedance matching: Selecting materials that match the impedance of acoustic waves to maximize the reflection or absorption of sound waves.

[0047] Sound absorption characteristics: The sound absorption performance of the material needs to be consistent with the design goals. It must effectively isolate the sound waves of the target frequency without affecting the transmission of other frequencies.

[0048] Thickness and density: The thickness and density of a material will affect its soundproofing effectiveness. Generally, thicker and denser materials have better soundproofing effects.

[0049] Environmental resistance: Materials need to have good durability and be able to maintain performance under various environmental conditions.

[0050] Fabrication and processing: The material should be easy to process and fabricate so that complex geometries can be achieved.

[0051] The following are some examples of materials:

[0052] Polyurethane foam: It has good sound absorption properties and is suitable for high-frequency sound insulation. The applicable frequency is above 2000Hz. The application scenarios are indoor acoustic treatment and sound-absorbing panels on the back of speakers. It has the characteristics of light weight, easy processing and low cost.

[0053] Mineral wool and glass wool: widely used in building sound insulation and have excellent sound absorption properties.

[0054] Sandwich composite material: composed of stacked materials of different densities and thicknesses, the multi-layer structure can achieve broad-spectrum sound insulation, suitable for medium to high frequencies, with frequencies between 500Hz-5000Hz, and application scenarios include building walls and sound barriers.

[0055] Sound-absorbing fiber and polymer composite materials: combine the advantages of fiber and polymer, with good sound absorption and sound insulation performance.

[0056] Aluminum and steel: High-density metal materials that are suitable for low-frequency sound insulation, but need to be combined with other materials to improve high-frequency sound insulation.

[0057] Rubber and silicone: have good damping properties, can absorb vibrations and sound waves, are suitable for low to medium frequencies, with frequencies between 50Hz-1000Hz, and are used in sound insulation and vibration control of mechanical equipment. They have high elasticity and good damping properties.

[0058] Furthermore, in order to achieve the best sound insulation effect, different materials can be used in combination. For example, in the FSS structure, metal materials can be used to form the reflective surface, and porous materials such as polyurethane foam or mineral wool can be added behind it to absorb the remaining sound waves. This combination can reflect high-frequency sound waves and absorb medium and low-frequency sound waves, achieving broad-spectrum sound insulation.

[0059] Furthermore, metamaterials with negative refractive index or other unique electromagnetic properties can be used to achieve more complex and efficient frequency selection characteristics; high dielectric constant materials can be used to make substrates to reduce the size of FSS units and improve frequency selectivity.

[0060] The multi-layer FSS is composed of multiple single-layer FSS structures stacked together with dielectric layers in between. The multi-layer structure can provide more complex frequency selectivity characteristics and improve bandwidth and performance.

[0061] Interlayer structure: can be FSS patterns of the same or different shapes and sizes.

[0062] Interlayer dielectric: The dielectric layer between each layer can be the same or different materials.

[0063] Interlayer dielectric material: can be selected to be the same or different material as the substrate to adjust the layer spacing and acoustic properties.

[0064] Alignment and bonding: Multi-layer FSS structures are precisely aligned through alignment technology and then bonded together using adhesives or lamination processes.

[0065] Lamination process: Lamination is carried out under high temperature and high pressure to firmly combine the multi-layer structure to form an overall FSS module.

[0066] The single-layer FSS structure is relatively simple, and the design and manufacturing process is relatively straightforward, which is suitable for some basic frequency selectivity requirements; due to its simple structure, the required materials and manufacturing process costs are relatively low, which is suitable for mass production; the single-layer structure is lighter than the multi-layer structure, which has advantages for some weight-sensitive applications (such as aerospace); it is suitable for occasions that require a thin design; it can be more easily integrated with other audio or RF devices, and is suitable for compact design.

[0067] The multi-layer FSS structure can achieve a wider operating frequency band and more complex frequency response characteristics, and is suitable for applications that require wide-band operation; through the multi-layer design, selective filtering of multiple frequency bands can be achieved, and is suitable for multi-band audio systems; the multi-layer structure can provide higher filtering accuracy and better ability to suppress out-of-band signals, thereby improving system performance; the multi-layer design allows the use of different FSS patterns and dielectric materials in different layers to achieve more flexible adjustment of acoustic characteristics; the multi-layer structure can achieve a higher quality factor (Q value), which is beneficial to improving the selectivity of the frequency response of the shielding box and reducing losses; the multi-layer FSS can realize the integration of multiple functions, such as having both reflection and transmission characteristics, or combining sound-absorbing materials to achieve more complex acoustic characteristics.

[0068] Further, as an example, the circular patch size is set to:

[0069]

[0070] Where: v is the speed of sound in the medium, which is related to the medium density and Young's modulus, ∈ r is the relative dielectric constant of the dielectric substrate, r is the radius of the circular patch, 1.841 is the zero point of the first root Bessel function, and f r is the operating frequency.

[0071] As an example, setting the rectangular patch size can be

[0072]

[0073] Where: v is the speed of sound in the medium, which is related to the medium density and Young's modulus, ∈ r is the relative dielectric constant of the dielectric substrate, f r is the operating frequency, L and W are the length and width of the rectangular patch, respectively, and m and n are integers of the resonant mode.

[0074] As an example, setting the square patch size can be

[0075]

[0076] a is the side length of the square patch or etched groove, v is the speed of sound in the medium, which is related to the medium density and Young's modulus, and f r is the operating frequency.

[0077] As an example, the rectangular ring etch groove dimensions may be set as:

[0078]

[0079] Where: v is the speed of sound in the medium, which is related to the medium density and Young's modulus, f r is the operating frequency

[0080] L avg is the average radius of the rectangular ring excavation, defined as (L in +L out ) / 2, where L in and L out are the inner and outer radius of the ring respectively.

[0081] As an example, the ring etch slot or patch size can be set to:

[0082]

[0083] r avg is the average radius of the circular undercut or patch, defined as (r in +r out ) / 2, where r in and r out are the inner and outer radius of the ring respectively.

[0084] As an example, set the size of the cross-shaped etching groove and define the lengths of the four arms as l1, l2, l3 and l4. For each arm, the corresponding resonant frequency f can be calculated separately. 0i (i=1, 2, 3, 4), when the substrate dielectric constant and arm width are the same:

[0085]

[0086] where v is the speed of sound.

[0087] The design process for the cross-shaped etching groove size is:

[0088] Determine the target frequency range: Determine the frequency range you want FSS to cover. It can be designed to cover a wide band or target specific multiple frequency points;

[0089] Select arm length: Set the respective resonant frequency f by selecting different arm lengths li 0i .

[0090] Determine the period a: Choose a suitable period a to ensure the periodicity and good frequency selectivity of the structure. Usually, the period a is still roughly 1.5 to 2 times the longest arm length.

[0091] Select arm width w: The selection of arm width w can be based on mechanical strength and manufacturing process considerations. Generally speaking, the arm width can be between 1 / 10 and 1 / 5 of the shortest arm length.

[0092] The basic idea of ​​the present invention is to combine the frequency selector with the audio shielding chamber, and by adjusting the parameters of the frequency selector, the shielding chamber can selectively shield the sound waves of a specific frequency, thereby filtering out unnecessary interference signals and ensuring the normal operation of the audio equipment. The frequency selector can be connected to an external control device through an interface;

[0093] By adjusting the frequency selector, the propagation of sound waves of specific frequencies in the shielding box can be controlled;

[0094] Use the filtering function of the frequency selector to remove or weaken unwanted interference signals;

[0095] Existing audio shielding chambers lack frequency selection functions and cannot optimize the processing of signals of specific frequencies. This results in the test equipment being easily interfered by non-target frequency signals during the test process, affecting the accuracy and reliability of the test results. FSS has no application in the direction of audio shielding.

[0096] In view of the above problems existing in the prior art, the present invention proposes a solution of integrating a frequency selector in an audio shielding chamber. By integrating an adjustable frequency selector in the shielding chamber, the solution enables the test equipment to selectively process and analyze specific frequency signals, significantly improving the accuracy and reliability of the test. Through this integrated design, the test system is simplified, the cost is reduced, and the overall performance of the system is enhanced.

[0097] Improve test accuracy: Through the integration of frequency selectors, the target frequency signal can be effectively shielded to improve the accuracy of test data.

[0098] Enhance system stability: Reduce interference from external noise and non-target frequency signals to ensure the stability of the test environment.

[0099] Simplify the testing process: The integrated design reduces the use of independent equipment and simplifies the system construction and operation process.

[0100] Reduce test costs: The integrated solution reduces the need for additional equipment, solves the problem of additional noise signals introduced by more external device interfaces, and reduces the cost of the overall test system.

[0101] The frequency selector adopts an adjustable design, which can adjust the shielding frequency range according to test requirements.

[0102] The selector module can be locally installed on the interface connector or integrated with the shielding box / room wall to achieve modular and customized design.

[0103] A frequency selector installation position is reserved inside the shielding box to ensure the integrity and stability of signal transmission.

[0104] Through the built-in control interface, users can directly adjust the operating parameters of the frequency selector outside the shielding box.

[0105] Furthermore, the FSS can be electrically tuned to adjust the frequency response in real time by applying an electric field or voltage.

[0106] The system has a built-in signal processing unit that can monitor and analyze the filtered frequency signal in real time.

[0107] Provides a data interface to support exporting analysis results to external devices for further processing and recording.

[0108] The frequency selector is used to adjust the sound wave propagation of a specific frequency in the shielding box; the filtering function of the frequency selector is used to remove or weaken the unnecessary interference signal.

[0109] Equipment connection and inspection: Ensure that the frequency selector is properly connected to the audio shielding box and external control equipment (such as a computer or handheld controller); check all connecting cables and interfaces, and confirm the correctness of the power supply and signal lines.

[0110] Start the frequency selector and control equipment and perform self-test procedures to ensure that the equipment is operating normally.

[0111] Load the preset frequency range and filter parameters and prepare to enter the working state.

[0112] The reference signal generation and input includes: generating a reference signal in the shielding box to cover the operating frequency range of the audio device to be tested; inputting the reference signal into the frequency selector to observe its response; using a spectrum analyzer to analyze the reference signal and record the frequency distribution in the shielding box; identifying the main interference frequency and target frequency to provide a basis for subsequent adjustments.

[0113] According to the spectrum analysis results, the initial parameters of the frequency selector are set, including the center frequency, bandwidth and gain; these parameters are input on the control device and applied to the frequency selector.

[0114] Gradually adjust the center frequency and bandwidth of the frequency selector and observe the changes in sound wave propagation in the shielding box.

[0115] The signal changes during the adjustment process are monitored by a spectrum analyzer to ensure that the target frequency signal is effectively attenuated.

[0116] According to the characteristics of the interference signal, select the appropriate frequency response design (such as bandpass and bandstop frequency response).

[0117] During the test, the signal inside the shielding box is monitored in real time and dynamically adjusted by electrical tuning through the feedback system.

[0118] According to the actual test situation, the parameters of the frequency selector are fine-tuned to achieve the best filtering effect.

[0119] Automated calibration includes:

[0120] The frequency selector is calibrated by electrical tuning using an automated control system and test conditions as feedback.

[0121] According to the feedback data, the working parameters of the frequency selector are adjusted to ensure effective operation in different environments.

[0122] In terms of manufacturing process, nano-manufacturing technology is used to make more sophisticated and complex FSS structures to improve performance; low-cost manufacturing: explore low-cost manufacturing processes, such as printed electronics technology, to reduce the cost of large-scale production.

[0123] It will be appreciated that in the development of any actual implementation, as in any engineering or design project, numerous implementation-specific decisions may be made. Such a development effort may be complex and time-consuming, but will be a routine task of design, fabrication, and production for those of ordinary skill having the benefit of this disclosure without undue experimentation.

[0124] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the present invention may be modified or replaced by equivalents without departing from the spirit and scope of the technical solutions of the present invention, which should all be included in the scope of the claims of the present invention.

Claims

1. Application of a frequency selector in an audio shielding chamber, characterized in that: include, Box body, the box body includes enclosures, and filling medium between / around the enclosures; It includes an interface connector, and the enclosure is provided with an etching groove or a patch.

2. The application of the frequency selector according to claim 1 in an audio shielding chamber is characterized in that: The etching groove or patch is square, circular, annular, rectangular or cross-shaped.

3. The application of the frequency selector according to claim 2 in an audio shielding chamber is characterized in that: Set the circular patch size to: Where: v is the speed of sound in the medium, which is related to the medium density and Young's modulus, ∈ r is the relative dielectric constant of the dielectric substrate, r is the radius of the circular patch, 1.841 is the zero point of the first root Bessel function, and f r is the operating frequency.

4. The design method of the radio frequency shielding box according to claim 2 is characterized in that: Set the size of the rectangular patch to Where: v is the speed of sound in the medium, which is related to the medium density and Young's modulus, ∈ r is the relative dielectric constant of the dielectric substrate, f r is the operating frequency, L and W are the length and width of the rectangular patch, respectively, and m and n are integers of the resonant mode.

5. The application of the frequency selector according to claim 2 in an audio shielding chamber is characterized in that: The rectangular ring etched groove size can be set as: Where: v is the speed of sound in the medium, which is related to the medium density and Young's modulus, f r is the operating frequency L avg is the average radius of the rectangular ring excavation, defined as (L in +L out ) / 2, where L in and L out are the inner and outer radius of the ring respectively.

6. The application of the frequency selector according to claim 2 in an audio shielding chamber is characterized in that: The ring etching groove or patch size can be set as: r avg is the average radius of the circular undercut or patch, defined as (r in +r out ) / 2, where r in and r out are the inner and outer radius of the ring respectively.

7. The application of the frequency selector according to claim 2 in an audio shielding chamber is characterized in that: Set the size of the cross-shaped etching groove and define the lengths of the four arms as l1, l2, l3 and l4. For each arm, the corresponding resonant frequency f can be calculated separately. 0i (i=1, 2, 3, 4), when the substrate dielectric constant and arm width are the same: where v is the speed of sound.

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