129 results about "Broadband noise" patented technology

The invention discloses an unmanned aerial vehicle soft landing control method based on track prediction and multi-source cooperative decoy, and the method comprises the steps: introducing a communication protocol recognition mechanism in a blocking process of an instruction link of an unmanned aerial vehicle, and achieving the conversion from extensive broadband suppression to protocol precise interference; the problems that in the prior art, power consumption is high, interference on legal communication is large, and the frequency hopping unmanned aerial vehicle resisting effect is insufficient can be effectively solved. In the scheme, signal integrity is guaranteed through monitoring and preprocessing, an unmanned aerial vehicle link protocol is identified through feature extraction and protocol library matching, and then a targeted interference template is generated, so that the interference effect can accurately fall on key positions such as a leader sequence, a CRC field, a subcarrier or a control frame and the like; therefore, synchronization, verification or data transmission can be destroyed under the condition of low power, and accidental damage of broadband noise to services such as co-frequency Wi-Fi and Bluetooth is avoided.

The invention relates to the field of aviation noise control, and provides an aircraft landing gear noise reduction device and method based on micro metal wire spiral winding. The device part comprises a metal wire and a metal wire fixing buckle, the metal wire is fixed through the metal wire fixing buckle, and meanwhile the size and material parameters of the metal wire are designed in a targeted mode. In the method part, the designed metal wire is wound on a cylindrical bluff body part, possibly generating vortex shedding and vortex-fixing interference, on the nose gear in a spiral winding manner, and the two ends and the axial interval position of the metal wire are fixed through the metal wire fixing buckles, so that the metal wire is ensured to be fastened. Therefore, through the wound metal wires, single-frequency noise in the over-top direction caused by falling of a towing rod vortex can be effectively eliminated, broadband noise is reduced, and the noise control capability of an airplane is improved. The method is suitable for various civil aircraft types, and has the advantages of being simple in structure, remarkable in noise reduction effect, high in practicability, high in adaptability and the like.

The invention discloses an unmanned aerial vehicle instruction link blocking interference method and device based on communication protocol identification, which can effectively solve the problems of high power consumption, large interference on legal communication and insufficient anti-frequency hopping unmanned aerial vehicle effect in the prior art by introducing a communication protocol identification mechanism in the unmanned aerial vehicle instruction link blocking process. Firstly, signal integrity is guaranteed through monitoring and preprocessing, then an unmanned aerial vehicle link protocol is identified through feature extraction and protocol library matching, and then a targeted interference template is generated, so that the interference effect can accurately fall on key positions such as a leader sequence, a CRC field, a subcarrier or a control frame and the like; and synchronization, verification or data transmission can be destroyed under a low-power condition, so that accidental damage of broadband noise to same-frequency Wi-Fi and Bluetooth services is avoided. Meanwhile, through a frequency hopping prediction model and a scheduling mechanism, the interference signal can follow the frequency hopping switching of the unmanned aerial vehicle in real time.

This invention discloses a broadband composite sound insulation structure, including a first sound insulation mechanism and a second sound insulation mechanism. The first and second sound insulation mechanisms are disposed opposite to each other, with a closed air layer formed between them. Through the arrangement of the first, second, and air layers, the broadband composite sound insulation structure of this invention can effectively reduce and suppress broadband noise, including high-frequency, mid-frequency, and low-frequency noise. By incorporating the first and second sound insulation panels, noise reduction can be achieved while minimizing external environmental pollution to both the first and second sound insulation layers.

The invention provides a broadband noise adaptive active noise reduction control method, which belongs to the technical field of noise reduction control, and comprises the following steps of: 1, acquiring and enhancing an original reference signal for target broadband noise; step 2, multi-channel coherence calibration is carried out based on the enhanced reference signal; step 3, generating a control signal based on the calibrated reference signal; 4, collecting an error signal based on an error microphone arranged in a vehicle compartment; and step 5, performing adaptive parameter updating based on the calibrated reference signal and error signal. The problems of slow algorithm convergence and poor noise reduction performance caused by inaccurate reference signal spectrum capture, easy pollution and poor multi-channel coherence in the existing method are solved, and efficient and stable control of broadband noise is realized.

The invention provides an alternating-current weak current high-precision detection system and method, and the system comprises a copper-nickel alloy shielding cover which is used for inhibiting space power frequency radiation interference and power system broadband noise, and a magnetic sensitive element which is used for converting the detected magnetic field change into a corresponding initial current signal, the trans-impedance amplifier is used for converting the initial current signal into a voltage signal; the adaptive noise suppression module collects a power frequency fundamental wave reference signal and a harmonic wave reference signal, generates a harmonic wave anti-phase counteracting signal, and performs anti-phase counteracting on real noise of the initial current signal; the analog-to-digital converter is used for converting the voltage signal into a discretized digital signal, and the discretized digital signal comprises a target signal and a random noise signal; and the FPGA coherent demodulation module is used for carrying out cross-correlation operation and narrow-band filtering on the target signal and the random noise signal to separate out a micro-current signal. The technical problems that in the prior art, composite noise covering is limited, the frequency fluctuation adaptability is poor, and microvolt-level signals are difficult to capture are solved.

The present disclosure provides a method for optimizing a broadband noise of an inductive magnetic field sensor as well as a magnetic field sensor, including: determining a functional relationship between an induced voltage of a coil and an effective permeability of a magnetic core of the inductive magnetic field sensor; determining an equivalent voltage noise expression of a temperature variation-induced permeability noise of the magnetic core according to the functional relationship; determining a key influencing factor of the magnetic core according to the equivalent voltage noise expression of the temperature variation-induced permeability noise of the magnetic core; modifying the magnetic core according to the key influencing factor of the magnetic core to optimize the temperature variation-induced permeability noise of the magnetic core; and constructing a dual-channel composite multi-stage modulation signal-noise separation circuit to optimize a low-frequency band noise and a high-frequency band noise of the inductive magnetic field sensor.

The invention relates to the technical field of biomedical signal processing and medical electronics, in particular to a blood pressure measuring method for non-invasive exercise blood pressure monitoring. The method aims to solve the technical problem of low blood pressure measurement accuracy caused by broadband noise interference and failure of a fixed parameter model in a motion state in the prior art. According to the technical scheme, the method comprises the steps that a cardiac cycle reference signal and a Korotkoff sound signal are synchronously collected, a sampling window is calculated in a self-adaptive mode by utilizing a cycle triggering feature point gating mechanism and combining a heart rate, and time domain precise interception of the signals is achieved; carrying out root mean square calculation and Savitzky-Golay filtering on the intercepted signal, and keeping waveform characteristics while denoising; constructing a multi-dimensional feature regression model containing a peak value, skewness, kurtosis and dynamic template similarity so as to accurately judge systolic pressure and diastolic pressure; an automatic recharging mechanism is triggered by monitoring signal quality, and strong interference is physically avoided. The method has the advantages of being high in anti-noise capacity, high in feature extraction robustness and accurate and reliable in measurement result.

This invention discloses a frequency conversion circuit, a wireless communication circuit, an apparatus, a system, and a method. The technical solution of this invention, through optimization and improvement of existing passive frequency conversion circuits, can further reduce costs. Furthermore, by directly feeding the broadband noise signal into the resonant unit from the second modulation port without other loss circuits, the path loss of the broadband noise signal can be reduced, thereby obtaining more oscillation signals. This allows more oscillation signals to be fed into the modulation element for mixing, ultimately resulting in more frequency conversion signals. In other words, with the same initial radio frequency signal power, the frequency conversion circuit can produce more frequency conversion signal power, correspondingly reducing the power consumption of the frequency conversion circuit and achieving a longer wireless operating distance.

The invention discloses a shielded cable electricity testing method based on ground loop impedance potential lifting, and relates to the technical field of measurement. The electroscope comprises an electricity testing step, an induction electrode on the cambered surface of the electroscope is used for obtaining induced electricity, a broadband direct sampling framework is formed on the physical level, and broadband direct sampling of millivolt-level power frequency displacement current characteristics is achieved. Based on a variational mode decomposition-Duffing oscillator fusion weak signal extraction algorithm, a variational mode decomposition algorithm is utilized to adaptively strip broadband noise and higher harmonics, a reconstructed signal is subjected to scale normalization and then introduced into a critical chaotic state Duffing oscillator algorithm, phase transition of a phase track from a chaotic attractor to a large-scale limit cycle is monitored, and a weak signal is extracted. A non-linear dynamic weak signal extraction algorithm is formed on the algorithm level, and weak power frequency features masked by strong noise are accurately recognized; a broadband direct acquisition framework and a weak signal extraction algorithm form a dual detection framework, and a quasi-induction electric signal is detected and judged in the live part verification process of the shielded cable.

This utility model discloses a negative pressure compressor silencer made of composite sound-absorbing material, including a negative pressure fan body and a silencer pipe fixedly installed on the air inlet end of the negative pressure fan body. An air inlet channel is fixedly installed on the inner wall of the silencer pipe, and a primary noise reduction mechanism is provided on the inner wall of the air inlet channel near the pipe opening. The primary noise reduction mechanism includes an air inlet cylinder fixedly installed on the inner wall of the air inlet channel, and multiple air inlets are opened on the outer wall of the air inlet cylinder. This utility model, through the inner ring silencer cylinder, outer ring silencer cylinder, and silencer ring cylinder of the primary noise reduction mechanism forming a multi-stage sound absorption structure, utilizes the cooperation between the silencer holes and the annular cavity to allow sound waves to reflect and diffract between different cavities, effectively absorbing mid-to-high frequency noise. The coaxial and annular array distribution design of the air inlets guides the airflow to enter evenly, reducing the generation of eddy noise. The composite structure of the perforated metal cylinder and the sound insulation felt further blocks the transmission of noise, improving the broadband noise reduction effect.

The utility model provides a centrifugal fan, including volute still include: impeller, the impeller is provided with at least two groups, and at least two groups impeller follow the axial direction of volute, the middle disc is arranged between two groups of adjacent impeller, two groups of adjacent impeller are separated through the middle disc, and the import of middle disc is linked together with the import of volute, each group impeller is provided with several blades, and several blades are arrayed around the axial direction of volute, and the blade of two groups of adjacent impeller is staggered along the projection direction of blade. Through the mode for increasing the number of blade, increase the times of cutting the airflow that enters the volute, thereby improved the frequency of rotation noise, namely BPF noise, make BPF noise frequency far away from the hearing range of human ear, and then reduce the situation that the user hears the rotation noise. In addition, the blade that interlaces can break the shedding vortex that the blade tail edge produces, reduces the broadband noise of fan.

The utility model discloses a silencing device for a ventilation system of a heating ventilation air conditioner, and relates to the technical field of heating ventilation air conditioner equipment, the silencing device comprises a ventilation pipeline and a silencing assembly, the silencing assembly is used for eliminating noise generated in the ventilation process of the interior of the ventilation pipeline, and the silencing assembly comprises a silencing laminated plate and a side position closing plate; the side closing plate is fixedly connected to the side face of the silencing laminated plate, and a first high-frequency absorption layer, a low-frequency absorption layer and a second high-frequency absorption layer are arranged between the silencing laminated plate and the side closing plate. According to the utility model, the high-frequency absorption layer I, the low-frequency absorption layer and the high-frequency absorption layer II are arranged to form the structure shaped like the Chinese character'pin ', so that noise with different frequencies is subjected to targeted absorption treatment. The high-frequency absorption layer adopts melamine foam plastic to effectively capture high-frequency sound wave energy, and the low-frequency absorption layer and the sound absorption cotton layer have a synergistic effect to absorb low-and-medium-frequency noise, so that comprehensive treatment of broadband noise generated by the ventilation system is realized.

An electronic system with heat dissipation and feed-forward active noise control function includes a fan module, an embedded controller, a reference microphone, a multi-channel speaker module, a beamforming control module and an active noise reduction controller. The beamforming control module controls the orientation of the multi-channel speaker module. The multi-channel speaker module provides anti-phase noise signals to cancel noise according to a speaker control signal. The reference microphone detects broadband noise generated by the fan module in operation to provide a corresponding broadband noise signal. A virtual microphone module of the active noise reduction controller provides a virtual error signal according to a transfer function between the reference microphone and a physical error microphone, a transfer function between the multi-channel speaker module and the physical error microphone and the broadband noise signal, and generates the speaker control signal according to a synchronization signal, the broadband noise signal and the virtual error signal.

The invention relates to the technical field of short-wave communication, and discloses a short-wave broadband frequency selection method, which realizes precise frequency selection of 12kHz / 24kHz broadband communication under the condition that traditional narrow-band short-wave equipment does not upgrade hardware through a cooperation mechanism of narrow-band detection signals and broadband ground noise monitoring. The method combines narrowband signal-to-noise ratio evaluation and broadband spectrum analysis, ensures that the selected frequency has optimal communication quality in both narrowband and broadband ranges, effectively solves the problem that traditional narrowband frequency selection cannot adapt to broadband services, has the advantages of environmental adaptation, high calculation efficiency, strong compatibility and the like, and is suitable for popularization and application. And the reliability and the economical efficiency of short-wave broadband communication are remarkably improved.

The invention relates to the technical field of building external envelope structures and green building energy conservation, in particular to an acoustic super-structure composite unit and a glass curtain wall, the acoustic super-structure composite unit comprises a first substrate, a second substrate and a middle substrate arranged between the first substrate and the second substrate; a local resonance module is arranged on the middle-layer substrate; a through hole is formed in the middle-layer substrate; a frame structure is further included; a first convex edge and a second convex edge are arranged on the frame structure; by integrating the photovoltaic module, the local resonance module, the middle-layer substrate and the thermal insulation layer formed by aerogel, on the premise that the thickness and the weight are not remarkably increased, the problem of function mutual exclusion among broadband noise pollution, heat loss and energy self-sufficiency is solved, and the thermal insulation effect is improved. And collaborative improvement of multi-physical field performance is realized.

The noise reduction device provided by the embodiment of the invention comprises a first air inlet, an air duct and a first air outlet, wherein the air duct comprises an air duct interval and a plurality of sub air ducts; the air channel interval is made of at least two different materials, and air reaches the first air outlet from the first air inlet through the multiple sub air channels. According to the embodiment of the invention, the larger air duct is divided into the plurality of sub-air ducts through the air duct interval, the air duct interval is made of at least two different materials, gas reaches the first air outlet from the first air inlet through the plurality of sub-air ducts and is exhausted, and the plurality of materials are combined to form the plurality of slender sub-air ducts; broadband noise generated by various gas flow rates can be reduced, the noise generated by various gas flow rates can be controlled at an ideal level, the contact area between gas and the partition wall surface of the air duct is increased through the multiple slender sub-air ducts, the gas flow rate in each slender sub-air duct is reduced, the vortex size is reduced, and the vortex effect is improved. When gas enters the area where the plurality of slender sub-air ducts are located, the acoustic impedance changes, and the noise level is effectively reduced.

This invention discloses a planar millimeter-wave or terahertz broadband noise source and its design method, comprising a low-pass filter, an input RF matching circuit, an avalanche noise diode, an output RF matching circuit, and a DC grounding circuit. The input terminal of the low-pass filter is biased to an external constant current source, and its output terminal is connected to the cathode of the avalanche noise diode through the input RF matching circuit. The anode of the avalanche noise diode is connected to the input terminal of the DC grounding circuit through the output RF matching circuit, and the output terminal of the DC grounding circuit outputs an RF signal. This invention achieves the output of a broadband high-frequency noise signal while greatly simplifying the design of the matching circuit. The overall circuit adopts a planar structure, and all components can be integrated on the same substrate, which not only facilitates integration with other circuits but also reduces the difficulty of fabrication and assembly, and reduces transmission losses.

The invention relates to a combined type energy storage equipment noise reduction system and a noise optimization method. The combined type energy storage equipment noise reduction system comprises a noise reduction cover body arranged corresponding to a refrigeration assembly, and a noise reduction control module is further arranged in the noise reduction cover body; the noise reduction cover body comprises a perforated aluminum plate and a split type sound absorption plate, the perforated aluminum plate is used as a high-frequency noise reflecting layer, the split type sound absorption plate is used as a medium-frequency noise dissipation layer, the noise reduction cover body further comprises a bottom vibration isolation module, and the bottom vibration isolation module is used as a low-frequency vibration isolation layer for restraining low-frequency vibration transmission; and combining to form a physical filtering noise reduction structure for suppressing broadband noise through a gradient structure.

This application relates to a method, apparatus, computer device, and storage medium for stripe noise removal. The method includes: acquiring a preprocessed image; processing the preprocessed image to form a low-frequency image and a high-frequency image; performing wavelet domain Fourier transform denoising processing on the low-frequency image; summing the result of the low-frequency image processing with the high-frequency image to remove broadband noise, obtaining a first processed image; performing Gaussian low-pass filtering on the first processed image; performing row mean difference on the images before and after Gaussian low-pass filtering and superimposing the row mean difference result pixel-by-pixel with the corresponding rows of the first processed image to remove narrow stripe noise, obtaining a second processed image; performing median filtering on the second processed image to remove particle noise in the image, and outputting a third processed image. This application can effectively remove both wide stripe noise and narrow stripe noise.

The utility model discloses a low-emission silencer of an air compressor, which belongs to the technical field of air compressors, and comprises a waste gas inlet pipe, a vertical filter tank is arranged at the bottom of the waste gas inlet pipe, a transverse connecting pipe is arranged at one end of the vertical filter tank, an emission silencing component is arranged at one end of the transverse connecting pipe, and the exhaust silencing component is arranged at the other end of the transverse connecting pipe. The discharging noise reduction assembly is composed of a first transverse discharging pipe, a filtering assembly and a second transverse discharging pipe, the filtering assembly is arranged at one end of the first transverse discharging pipe, dust and particulate matter can be effectively filtered through a stainless steel funnel-shaped filtering net, discharging pollution is reduced, and through the design of a vertical scraping plate and a detachable circular material receiving pipe, the discharging noise reduction effect is good. The air compressor is more convenient to clean and maintain, the maintenance cost is reduced, the noise of the air compressor can be remarkably reduced through the design of the first sound absorption layer, the second sound absorption layer and the circular silencing pipe, broadband noise, especially low-frequency noise, can be effectively absorbed, and the silencing effect is improved.

The application discloses a three-dimensional composite super-structure muffler module and a muffler. The muffler module comprises a rigid three-dimensional zigzag cavity structure and porous or fibrous material located around the cavity. The cavity structure is composed of a perforated panel, a multilayer coiled cavity and a partition. The coiled cavity is a multilayer structure, and each layer of the cavity is separated into a labyrinth-shaped channel by a coiled plug. The coiled porous or fibrous material around the cavity has high porosity. The application utilizes the high-frequency muffling characteristics of the porous or fibrous material and the low-frequency muffling characteristics of the super-structure material. The designed composite muffler has low-frequency and broadband muffling effects, can attenuate low-frequency single-frequency noise or broadband noise, and simultaneously greatly reduces the use of porous or fibrous material compared with a traditional resistive muffler. Furthermore, the muffler can be designed as an array-type muffler, and can be used in actual production and life, such as a substation, a mine site, a cooling tower and the like, which have a fan system and require large-area muffling and noise reduction.

The invention provides a communication interference type identification method and device and a storage medium, and belongs to the technical field of interference identification, and the method comprises the steps: obtaining a plurality of original IQ data from an unmanned plane broadband receiver; performing signal analysis on all the original IQ data to obtain a plurality of signal analysis results; and identifying and analyzing all signal analysis results to obtain a communication interference type identification result. According to the method, the calculation complexity is reduced, the processing speed is improved, multiple communication interference types can be recognized more comprehensively and accurately, the recognition accuracy of complex interference types such as broadband noise interference is remarkably improved, real-time recognition can be achieved under limited resources of the unmanned aerial vehicle, and the method is suitable for popularization and application. The problem that a single sub-channel is difficult to effectively identify broadband interference is solved, and the actual requirements of unmanned aerial vehicle reconnaissance confrontation can be met.

The utility model discloses a broadband noise reduction silencer which comprises a rectangular cylindrical barrel extending transversely, a plurality of air inlet connecting through holes are formed in a right side plate of the cylindrical barrel, and a plurality of air inlet connectors are welded and fixed to the right side plate of the cylindrical barrel. The interiors of the air inlet connectors are inserted into the corresponding air inlet connecting through holes and are communicated with the cylindrical barrel; a main air outlet through hole is formed in the middle of a left side plate of the cylindrical barrel, the right end of a main air outlet connector is clamped in the main air outlet through hole, the outer side wall of the right end of the main air outlet connector is welded and fixed to the inner side wall of the main air outlet through hole, and the main air outlet connector is communicated with the cylindrical barrel. According to the invention, the multiple air inlet connectors are arranged, so that communication and noise reduction of multiple pipelines can be realized, meanwhile, the filter plate can be used for filtering entering air, and the air inlet pipe is convenient to mount, dismount and replace and good in use effect.

The invention discloses a solid-state power amplifier for broadband noise suppression. The solid-state power amplifier comprises an amplifying unit, a filtering unit, a transceiving switch, a matching network unit and a control unit for controlling which are connected with one another, the amplification unit comprises four stages of amplification units which are in a step-by-step driving amplification mode from the front end to the rear end, the first stage of amplification unit adopts a low-noise amplifier to amplify weak signals and reduce introduction of noise, the driving stage amplification unit and the pushing stage amplification unit further amplify preceding stage signals, and the final stage amplification unit adopts a power tube; the system further comprises a frequency hopping filter. According to the scheme, the frequency hopping filter is introduced into the power amplifier, broadband noise is suppressed, and the signal-to-noise ratio of the power amplifier is improved.

The utility model provides a gear acoustic metamaterial structure for wide band noise reduction, include: bottom plate and set up on the acoustic metamaterial unit of bottom plate, acoustic metamaterial unit includes several layers of resonant cavity, and resonant cavity is different section radius and coaxial setting's cylinder cavity respectively, the outer wall of each layer resonant cavity is provided with the opening of vertical through -penetration respectively, the inner wall of the resonant cavity of outermost layer and the outer wall of other resonant cavity are provided with gear structure respectively, the utility model discloses first introduce multilayer gear shape resonant cavity to acoustic metamaterial, and the gear -like structure is strengthened sound wave reflection and energy dissipation to break through the performance limit of traditional helmholtz resonator.

The invention discloses a cross-flow fan and an electrical product comprising the same, and belongs to the technical field of ventilation devices. The cross-flow fan comprises a plurality of fan sections, each fan section is composed of fan blades and a blade hub, a plurality of sawteeth are arranged on the outer surfaces of the fan blades, the sawteeth are distributed at intervals in the length direction of the fan blades, and the extending direction of the sawteeth is perpendicular to the front edge direction of the fan blades. A boundary layer can be formed when airflow flows on the surface of the fan blade, and a turbulent flow structure in the boundary layer can generate random pressure pulsation on the surface of the blade, which is one of the main causes for generating broadband noise. According to the cross-flow fan, the flowing state of air in the boundary layer of the fan blade is changed by arranging the sawteeth on the surface of the fan blade, and the surface vortex structure is scattered in advance, so that the noise in the running process of the cross-flow fan is reduced.

The present application relates to the field of high-precision current sensor insulation state online detection method, and discloses a kind of high-precision current sensor withstand voltage detection method, including in the listening window of load current zero interval, the differential sampling synchronized with high-voltage bus on-off state is carried out to generate the differential current value of the leakage current, the present method passes through the on-off behavior of high-voltage bus as synchronous signal, the static working current of sensor is differentially sampled in very short time scale, it not only can eliminate the slow temperature drift caused by ambient temperature change, more can inhibit the asynchronous broadband noise universally existing in power electronic system from mechanism, so that the weak leakage current signal generated by high voltage previously submerged is identified as a differential value, so that the online evaluation of insulation performance is established on a certain physical cause and effect.

The utility model discloses a folded plate buckling type railway sound barrier metamaterial unit plate, which comprises two adjacent panels, a box body is clamped in the panels, a first sound nest and a second sound nest are clamped in the box body, one side of each panel is clamped with a back plate, and the other side of each panel is clamped with a baffle plate. A first positioning groove and a second positioning groove are formed in the outer walls of the two sides of the face plate respectively, positioning folded plates are arranged at the positions, corresponding to the second positioning groove, of the outer walls of the two sides of the back plate, and the positioning folded plates are clamped in the second positioning groove. According to the utility model, a rivet-free buckling structure is designed, the structure is not easy to deform, the anti-fatigue life is long, the metamaterial sound absorption assembly is easy to assemble and can be disassembled and replaced, the metamaterial sound absorption assembly composed of the sound pits with different sizes is designed, and sound waves are guided to be reflected for multiple times inside through the sound pits, so that the propagation path of the sound waves is increased, and the energy of the sound waves is reduced; and the sound waves of different sound pits can be interfered and offset, so that the noise reduction effect is improved, and the advantages of large sound insulation amount and broadband noise reduction are achieved.

The invention discloses a composite noise reduction structure based on a local resonance principle and a preparation method thereof, and belongs to the field of design and processing of composite noise reduction structures. The structure comprises an epoxy resin supporting panel, a metal ring-elastomer local resonance unit and a porous material, and efficient suppression of broadband noise is achieved through combination of the local resonance effect and the porous sound absorption characteristic. The resonance unit is of a structure in which a metal ring and an elastic body are mechanically embedded and are in mirror distribution; the elastic body is of a stepped cylinder structure, the metal ring is nested on a small-diameter cylinder, and the metal ring is a double-layer elastic supporting body with radial rigidity gradient after mirroring; the epoxy resin supporting panel is poured and formed through a steel mold, the elastic body is poured through a split mold, a metal ring cutting process and a porous material are processed and prepared according to requirements, and all the components are assembled into a whole through an adhesive. The invention has the advantages of obvious noise reduction effect, light weight, strong durability, simple preparation process and the like, and is suitable for noise control in various different application scenes.