Construction site regional active noise barrier system based on acoustic dome

Abstract

The application discloses a construction site regional active noise reduction barrier system based on a sound wave dome, which comprises a barrier main body, a reference microphone array, a control system, an error microphone and a feedback control module. The barrier main body comprises a cage frame covered on a construction site, and a micro-perforated sound absorption board and a noise reduction interlayer are arranged on the inner side of the cage frame. The reference microphone array is used for collecting multi-channel sound pressure data and phase information in the construction site in real time. The control system is used for establishing a time-space model of internal noise based on the multi-channel sound pressure data and phase information collected by the reference microphone array, and performing a multi-channel adaptive control algorithm to calculate the driving phase and amplitude of each loudspeaker so that the loudspeaker array emits a superimposed sound field. The error microphone is used for collecting sound pressure data and phase information at a desired noise reduction position. The feedback control module is used for generating an error signal, and the error signal is fed back to the control system after delay compensation on a driving phase and amplitude compensation signal to adjust the phase and amplitude of the loudspeaker driving signal.

Description

Technical Field

[0001] This invention relates to the field of acoustic barrier technology, specifically to a regional active noise reduction barrier system for construction sites based on acoustic domes. Background Technology

[0002] Construction sites generate broadband, high-intensity noise from concrete pouring, vibration, and material crushing, posing serious occupational health risks to nearby personnel. Currently, noise control at construction sites mainly employs passive sound barriers and single-point or non-matrix active noise reduction solutions, but both have significant shortcomings.

[0003] Passive noise barriers typically employ sound-absorbing materials, reflectors, or heavy-duty enclosures to physically reduce the propagation of direct sound. These solutions only reduce some mid-to-high frequency noise, offering very poor performance for low frequencies. Furthermore, reverberation and diffraction effects within the barrier lead to sound energy accumulation, resulting in relatively high external transmitted noise. In addition, passive barriers are usually rigid structures fixed by welding or bolts, making it difficult to quickly adjust their height and span according to the site dimensions, and also limiting their flexible deployment in non-rectangular or irregular locations.

[0004] Single-point or non-matrix active noise cancellation is often used for local noise control (e.g., earmuffs, pipe mufflers). However, these solutions use a small number of microphones and speakers to cancel noise at specific points through feedforward or feedback. However, noise sources at construction sites are multi-source, time-varying, and widely spatially distributed. Single-point or limited-channel active noise cancellation cannot form a uniform noise reduction area in a large three-dimensional space, often resulting in a comb-like filtering effect of localized silencing and enhancement.

[0005] Furthermore, in terms of active noise reduction control algorithms, most existing systems employ single-channel or simple multi-channel LMS algorithms without incorporating transmission path comparison and phase vector alignment. Inside the barrier, the reverse sound waves emitted by the loudspeakers propagate through the air and re-enter the reference microphone, creating acoustic feedback and causing the algorithm to diverge. Additionally, the phase differences between different loudspeakers reaching the same error microphone are not compensated for, preventing the reverse wavefronts from being superimposed in phase, significantly reducing the noise reduction effect.

[0006] Therefore, there is an urgent need for a regional noise reduction barrier system that can take into account both mid-to-high frequency sound absorption and low-frequency active cancellation, adapt to the dynamic changes of construction noise in a large area, and has closed-loop feedback correction capabilities. Summary of the Invention

[0007] The purpose of this invention is to provide a regional active noise reduction barrier system for construction sites based on acoustic domes, which can take into account both mid-to-high frequency sound absorption and low-frequency active cancellation, adapt to the dynamic changes of construction noise in a large area, and has closed-loop feedback correction capability.

[0008] To address the aforementioned technical problems, this invention provides a regional active noise reduction barrier system for construction sites based on acoustic domes, comprising:

[0009] The barrier body includes a cage frame installed on the construction site. Micro-perforated sound-absorbing panels are installed on the inner side of the cage frame. A noise reduction interlayer is provided between the micro-perforated sound-absorbing panels and the cage frame. The noise reduction interlayer includes a cavity that forms an air layer with the micro-perforated sound-absorbing panels. A matrix-arranged loudspeaker array is provided in the cavity.

[0010] A reference microphone array is placed inside the main body of the barrier to collect multi-channel sound pressure data and its phase information in real time at the construction site;

[0011] The control system is used to establish a spatiotemporal model of internal noise based on the multi-channel sound pressure data and its phase information collected by the reference microphone array, and to execute a multi-channel adaptive control algorithm to calculate the driving phase and amplitude of each loudspeaker so that the loudspeaker array emits a superimposed sound field with the same sound pressure as the internal noise and opposite phase.

[0012] Error microphone, used to collect sound pressure data and phase information at the desired noise reduction location;

[0013] The feedback control module is used to generate an error signal based on the sound pressure data and phase information collected by the error microphone, calculate the drive phase and amplitude compensation signal according to the error signal, and feed the drive phase and amplitude compensation signal back to the control system after delay compensation, so that the control system can adjust the phase and amplitude of the speaker drive signal according to the feedback signal.

[0014] Furthermore, the multi-channel adaptive control algorithm executed by the control system includes: using a multi-channel filtering minimum mean square algorithm as a gradient descent adaptive filter, wherein the reference signal is filtered by the estimated secondary path model and then used to update the adaptive filter coefficients of each speaker channel.

[0015] Furthermore, the multi-channel adaptive control algorithm also includes transmission path comparison and phase vector alignment processing. The transmission path comparison processing includes: dynamically estimating and canceling the feedback path components from the loudspeaker to the reference microphone by comparing the correlation between the reference microphone signal and the error microphone signal, so as to purify the reference signal. The phase vector alignment processing includes: measuring the secondary path phase response from each loudspeaker to each error microphone, setting the reference phase, performing phase pre-compensation on the drive signal of each loudspeaker or performing phase rotation on the filtered signal, so that the reverse sound waves of each loudspeaker at the error microphone are superimposed in phase.

[0016] Furthermore, the cage frame includes several retractable columns and several retractable beams. The beams are connected end to end to form a rectangular frame structure, and the columns are supported between the beams and the ground. The height and span of the columns and beams are adjusted according to the site dimensions.

[0017] Furthermore, the crossbeam includes telescopic sections and fixed sections connected sequentially at intervals. The outer side of the fixed section is provided with a ring-shaped fixing seat. The fixing seat has several first mounting holes arranged around the circumference of the crossbeam. The bottom of the column is fixedly installed on the ground by a base. The top of the column is connected to the fixing seat by a U-shaped fork. The U-shaped fork has a second mounting hole that matches the first mounting hole. The U-shaped fork and the fixing seat are fixedly connected by fasteners. The column is connected to the first mounting holes in different directions around the fixing seat by the U-shaped fork to adjust the pitch angle between the column and the crossbeam.

[0018] Furthermore, the outer edge of the fixing base is provided with an inwardly recessed groove, which corresponds one-to-one with the first installation position. The inner side of the U-shaped fork ear is provided with a locking block that fits into the groove. When the U-shaped fork ear is connected to the fixing base, the locking block is embedded in the groove.

[0019] Furthermore, the noise reduction interlayer includes a speaker mounting plate; one side of the speaker mounting plate is connected to a cage frame at a corresponding position via a detachable bracket; at least one speaker facing the micro-perforated sound-absorbing plate is mounted on the other side of the speaker mounting plate; the speakers on several speaker mounting plates form a speaker array.

[0020] Furthermore, the speaker mounting plate is fixedly connected to the noise reduction interlayer via vibration damping pads.

[0021] Furthermore, the detachable bracket includes a support rod, one end of which is connected to the speaker mounting plate via a swivel joint that can be limited, and the other end of which is connected to the cage frame via a clamp.

[0022] The beneficial effects of this invention are as follows:

[0023] 1. By coordinating the cage-like frame, micro-perforated sound-absorbing panels, and a matrix-arranged speaker array within the noise-reducing interlayer, and with the array microphones collecting real-time data on internal sound pressure and phase, a spatiotemporal model of the internal noise is established through the control system, generating a reverse superimposed sound field. This approach can balance mid-to-high frequency sound absorption with active low-frequency cancellation. Simultaneously, the error microphone and feedback control module perform secondary sampling of residual noise at the desired noise reduction location, and introduce delay compensation and drive gain adjustment to form a closed-loop control, thereby improving the system's stability.

[0024] 2. The micro-perforated sound-absorbing panel and the noise-reducing interlayer in this application together constitute the acoustic interface. The micro-perforated sound-absorbing panel not only provides a matrix installation space for the speaker array, but its resonant sound absorption effect with the noise-reducing interlayer attenuates the mid-to-high frequency components, reduces the burden on the active control system, and reduces internal reverberation, creating good acoustic conditions for active noise reduction. This integrated acoustic design of the structure enhances physical sound insulation and active noise reduction, improving the overall noise reduction performance. Attached Figure Description

[0025] The accompanying drawings, which are included to provide a further understanding of this application and form part of this application, use the same reference numerals to denote the same or similar parts. The illustrative embodiments of this application and their descriptions are used to explain this application and do not constitute an undue limitation of this application. In the drawings:

[0026] Figure 1 This is a schematic diagram of one embodiment of the present invention;

[0027] Figure 2 This is a schematic diagram of the top structure of a cage frame according to an embodiment of the present invention;

[0028] Figure 3 This is a schematic diagram of the connection structure between the U-shaped fork lug and the fixed base according to an embodiment of the present invention;

[0029] Figure 4 This is a schematic diagram of the connection structure between the U-shaped fork lug and the fixed base according to another embodiment of the present invention;

[0030] Figure 5 This is a schematic diagram of a U-shaped fork lug structure according to an embodiment of the present invention;

[0031] Figure 6 This is a schematic diagram of the structure of a noise reduction interlayer according to an embodiment of the present invention.

[0032] The components are: 1. Crossbeam; 11. Fixed section; 12. Telescopic section; 13. Connector; 2. Fixed base; 21. First mounting hole; 22. Groove; 3. U-shaped fork ear; 31. Locking block; 4. Column; 5. Micro-perforated sound-absorbing panel; 6. Noise-reducing interlayer; 61. Speaker mounting plate; 62. Speaker; 63. Vibration damping pad; 64. Universal connector. Detailed Implementation

[0033] like Figure 1 The regional active noise reduction barrier system for construction sites based on acoustic domes, as shown, includes:

[0034] The barrier body includes a cage-like frame installed on the construction site. A micro-perforated sound-absorbing panel 5 is installed inside the cage-like frame. A noise-reducing interlayer 6 is provided between the micro-perforated sound-absorbing panel 5 and the cage-like frame. The noise-reducing interlayer 6 includes a cavity that forms an air layer with the micro-perforated sound-absorbing panel 5. A matrix-arranged array of loudspeakers 62 is provided within the cavity. The cavity at the rear of the micro-perforated sound-absorbing panel 5 (the air layer in the noise-reducing interlayer 6) constitutes a resonant sound-absorbing structure, primarily absorbing mid-to-high frequency noise. The perforated sound-absorbing panel 5 is arranged on the surface of the loudspeaker 62 array, mainly for actively canceling low-frequency noise.

[0035] A reference microphone array is placed inside the main body of the barrier to collect multi-channel sound pressure data and its phase information in real time at the construction site. The reference microphone array can be installed in the work areas such as concrete pouring, vibration, and material crushing, or at key locations on the inner wall of the barrier (such as the top center of the barrier system).

[0036] The control system is used to establish a spatiotemporal model of internal noise based on the multi-channel sound pressure data and its phase information collected by the reference microphone array, and to execute a multi-channel adaptive control algorithm to calculate the driving phase and amplitude of each loudspeaker 62, so that the loudspeaker 62 array emits a superimposed sound field with the same sound pressure as the internal noise and opposite phase.

[0037] Error microphones are used to collect sound pressure data and phase information at the desired noise reduction location (such as the boundary of the work area), i.e., to directly measure residual sound pressure.

[0038] The feedback control module is used to generate an error signal based on the sound pressure data and phase information collected by the error microphone, calculate the drive phase and amplitude compensation signal according to the error signal, and after delay compensation of the drive phase and amplitude compensation signal, use PID to feed back to the control system, so that the control system adjusts the phase and amplitude of the speaker 62 drive signal according to the feedback signal.

[0039] This application utilizes the synergy of a cage-like frame, micro-perforated sound-absorbing panels 5, and a matrix-arranged array of 62 loudspeakers within a noise-reducing interlayer 6. Combined with real-time acquisition of internal sound pressure and phase by array microphones, a spatiotemporal model of the internal noise is established through a control system, generating a reverse superposition sound field. This approach effectively balances mid-to-high frequency sound absorption with active low-frequency cancellation. Simultaneously, an error microphone and feedback control module perform secondary sampling of residual noise at the desired noise reduction location, incorporating delay compensation and drive gain adjustment to form a closed-loop control, thus improving system stability. Furthermore, the micro-perforated sound-absorbing panels 5 and the noise-reducing interlayer 6 together constitute the acoustic interface. The micro-perforated sound-absorbing panels 5 not only provide matrix-style installation space for the 62 loudspeaker array, but their resonant sound absorption with the noise-reducing interlayer 6 also attenuates mid-to-high frequency components, reducing the burden on the active control system and lowering internal reverberation, creating favorable acoustic conditions for active noise reduction. This integrated structural and acoustic design mutually enhances physical sound insulation and active noise reduction, improving overall noise reduction performance.

[0040] According to one embodiment of this application, the multi-channel adaptive control algorithm executed by the control system includes: using a multi-channel filtering minimum mean square algorithm as a gradient descent adaptive filter, wherein the reference signal is filtered by the estimated secondary path model and then used to update the adaptive filter coefficients of each of the 62 channels of the loudspeakers.

[0041] According to one embodiment of this application, the multi-channel adaptive control algorithm further includes transmission path comparison and phase vector alignment processing. The transmission path comparison processing includes: dynamically estimating and canceling the feedback path components from the speaker 62 to the reference microphone by comparing the correlation between the reference microphone signal and the error microphone signal, so as to purify the reference signal; the phase vector alignment processing includes: measuring the phase response of the secondary path from each speaker 62 to each error microphone, setting a reference phase, performing phase pre-compensation on the drive signal of each speaker 62 or performing phase rotation on the filtered signal, so that the reverse sound waves of each speaker 62 at the error microphone are superimposed in phase. Transmission path comparison can eliminate the positive feedback caused by the sound of the speaker 62 re-entering the reference microphone, preventing system howling; phase vector alignment makes multiple reverse sound waves superimposed in phase at the error point, avoiding mutual cancellation and accelerating algorithm convergence; even if the secondary path changes (such as temperature and humidity affecting the sound speed), the phase compensation can still maintain alignment, and the noise reduction performance is stable.

[0042] According to one embodiment of this application, the cage frame includes several retractable aluminum alloy or steel columns 4 and several retractable crossbeams 1, the crossbeams 1 being connected end to end to form a rectangular frame structure (e.g., Figure 2As shown in the diagram, several columns 4 are supported between the crossbeam 1 and the ground; the height and span of the columns 4 and the crossbeam 1 are adjusted according to the site dimensions. The telescopic design employs an inner and outer tube structure, with the inner tube sliding within the outer tube, adjustable from 0.5 to 2 meters to accommodate barriers of varying widths. The telescopic columns 4 also utilize an inner and outer tube structure; the inner and outer tubes can be fixed in their telescopic length using an eccentric locking handle or safety pin. By adopting a telescopic structure, the same barrier can quickly adapt to different sized work areas (e.g., from 3m×3m to 8m×5m) without requiring redesign or manufacturing; installation is also quick and easy, facilitating transportation.

[0043] According to one embodiment of this application, the crossbeam 1 includes a telescopic section 12 and a fixed section 11 connected sequentially at intervals; as shown... Figure 3 and Figure 4 As shown, the outer side of the fixed section 11 is provided with a ring-shaped fixed seat 2. The fixed seat 2 is provided with a plurality of first mounting holes 21 arranged around the crossbeam 1. The bottom of the column 4 is fixedly installed on the ground by a base. The top of the column 4 is connected to the fixed seat 2 by a U-shaped fork lug 3. The U-shaped fork lug 3 is provided with a second mounting hole that mates with the first mounting holes 21. The U-shaped fork lug 3 and the fixed seat 2 are fixedly connected by fasteners. The column 4 is connected to the first mounting holes 21 in different directions around the fixed seat 2 by the U-shaped fork lug 3 to adjust the pitch angle between the column 4 and the crossbeam 1. The fixing seat 2 can be fixed to the crossbeam 1 by integral molding or welding. A set of first mounting holes 21 (threaded holes) are set every 20°-40° along the circumference of the crossbeam 1. The U-shaped fork lug 3 is welded to the top of the column 4. The two arms of the U-shaped fork lug 3 have coaxial second mounting holes. The holes at different angles on the fixing seat 2 are aligned with the U-shaped fork lug 3. The bolts are inserted and tightened to achieve an angle change of 5°~30° between the column 4 and the crossbeam 1. With the adjustable length of the upright, the footing point of the column 4 can be adjusted to adapt to the sloping or irregular ground.

[0044] According to one embodiment of this application, the outer edge of the fixing base 2 is provided with an inwardly recessed groove 22, the groove 22 corresponding one-to-one with the position of the first mounting hole 21, and the inner side of the U-shaped fork lug 3 is provided with a locking block 31 that conformally fits the groove 22 (e.g., Figure 5 As shown), when the U-shaped fork lug 3 is connected to the fixed base 2, the locking block 31 is embedded in the groove 22. During installation, when the U-shaped fork lug 3 is fitted onto the fixed base 2, the locking block 31 automatically slides into the groove 22 and locks in place. This not only facilitates installation and positioning, making it convenient for the U-shaped fork lug 3 and the fixed base 2 to be installed, but also improves the connection stability between the U-shaped fork lug 3 and the fixed base 2. According to one embodiment of this application, the noise reduction interlayer 6 is connected to the cage frame at the corresponding position via a detachable bracket; as shown... Figure 6As shown, a speaker mounting plate 61 is provided within the noise reduction interlayer 6. The speaker 62 is fixedly mounted on the speaker mounting plate 61, with the opening of the speaker 62 facing the micro-perforated sound-absorbing plate 5. The front of the speaker 62 is perpendicular to the mounting plate, pointing towards the interior space of the barrier, and maintaining a gap of 10-20mm with the micro-perforated plate. Two to four speakers 62 are mounted on each mounting plate, and multiple mounting plates are spliced ​​together to cover the entire inner wall of the barrier. The specific installation of the speakers 62 can be based on the sound field simulation results, arranging speakers 62 of different densities in different areas (e.g., increasing density near the noise source).

[0045] According to one embodiment of this application, the speaker mounting plate 61 is fixedly connected to the noise-reducing interlayer 6 via a vibration-damping pad 63. The vibration-damping pad 63 can be made of rubber / silicone gaskets. The speaker mounting plate 61 has mounting holes, and the vibration-damping pad 63 is disposed between the speaker 62 frame and the mounting holes. By providing the vibration-damping pad 63, vibration transmission can be prevented. The mechanical vibration generated when the speaker 62 is working is absorbed by the vibration-damping pad 63 and will not be transmitted to the frame to radiate noise. At the same time, it also reduces the fatigue damage of vibration to the speaker 62's own solder joints and cone, extending the life of the speaker 62. In order to reduce structural sound transmission, a rubber / silicone gasket can also be added between the detachable bracket and the cage frame.

[0046] According to one embodiment of this application, the detachable bracket includes a support rod. One end of the support rod is connected to the speaker mounting plate 61 via a locating universal joint 64, and the other end of the support rod is connected to the cage frame via a clamping member. The universal joint 64 can be a ball joint or a double-axis hinge structure, allowing for ±20° tilt adjustment, and is fixed by a locking nut after adjustment. The clamping member can be a U-bolt or a spring clamp, which can be quickly clamped onto the round or square tube column 4 / beam 1. By using the locating universal joint 64, the angle of the noise-reducing interlayer 6 can be adjusted. The support rod can also be a telescopic rod to adapt to different frame sizes, eliminating the need to customize brackets for each frame spacing and enhancing versatility.

[0047] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention, and all such modifications or substitutions should be covered within the scope of the claims of the present invention.

Claims

1. A regional active noise reduction barrier system for construction sites based on acoustic domes, characterized in that, include: The barrier body includes a cage-like frame installed on the construction site. A micro-perforated sound-absorbing panel is installed on the inner side of the cage-like frame. A noise reduction interlayer is provided between the micro-perforated sound-absorbing panel and the cage-like frame. The noise reduction interlayer includes a cavity that forms an air layer with the micro-perforated sound-absorbing panel. A matrix-arranged loudspeaker array is provided in the cavity. A reference microphone array is placed inside the main body of the barrier to collect multi-channel sound pressure data and its phase information in real time at the construction site; The control system is used to establish a spatiotemporal model of internal noise based on the multi-channel sound pressure data and its phase information collected by the reference microphone array, and to execute a multi-channel adaptive control algorithm to calculate the driving phase and amplitude of each loudspeaker so that the loudspeaker array emits a superimposed sound field with the same sound pressure as the internal noise and opposite phase. Error microphone, used to collect sound pressure data and phase information at the desired noise reduction location; The feedback control module is used to generate an error signal based on the sound pressure data and phase information collected by the error microphone, calculate the drive phase and amplitude compensation signal according to the error signal, and feed the drive phase and amplitude compensation signal back to the control system after delay compensation, so that the control system can adjust the phase and amplitude of the speaker drive signal according to the feedback signal.

2. The barrier system according to claim 1, characterized in that, The multi-channel adaptive control algorithm executed by the control system includes: using a multi-channel filtering minimum mean square algorithm as a gradient descent adaptive filter, wherein the reference signal is filtered by the estimated secondary path model and then used to update the adaptive filter coefficients of each speaker channel.

3. The system according to claim 2, characterized in that, The multi-channel adaptive control algorithm further includes transmission path comparison and phase vector alignment processing. The transmission path comparison processing includes: dynamically estimating and canceling the feedback path components from the loudspeaker to the reference microphone by comparing the correlation between the reference microphone signal and the error microphone signal, so as to purify the reference signal. The phase vector alignment processing includes: measuring the secondary path phase response from each loudspeaker to each error microphone, setting a reference phase, performing phase pre-compensation on the drive signal of each loudspeaker or performing phase rotation on the filtered signal, so that the reverse sound waves of each loudspeaker at the error microphone are superimposed in phase.

4. The barrier system according to any one of claims 1-3, characterized in that, The cage-like frame includes several retractable columns and several retractable beams. The beams are connected end to end to form a rectangular frame structure, and the columns support the beams between the beams and the ground. The height and span of the columns and beams are adjusted according to the site dimensions.

5. The barrier system according to claim 4, characterized in that, The crossbeam includes telescopic sections and fixed sections connected sequentially at intervals. The outer side of the fixed section is provided with a ring-shaped fixing seat. The fixing seat has several first mounting holes arranged around the circumference of the crossbeam. The bottom of the column is fixedly installed on the ground by a base. The top of the column is connected to the fixing seat by a U-shaped fork. The U-shaped fork has a second mounting hole that mates with the first mounting holes. The U-shaped fork and the fixing seat are fixedly connected by fasteners. The column is connected to the first mounting holes in different directions around the fixing seat by the U-shaped fork to adjust the pitch angle between the column and the crossbeam.

6. The barrier system according to claim 5, characterized in that, The outer edge of the fixing base is provided with an inwardly recessed groove, which corresponds one-to-one with the first installation position. The inner side of the U-shaped fork lug is provided with a locking block that fits into the groove. When the U-shaped fork lug is connected to the fixing base, the locking block is embedded in the groove.

7. The barrier system according to claim 5, characterized in that, The noise reduction interlayer is connected to the cage frame at the corresponding position via a detachable bracket; a speaker mounting plate is provided inside the noise reduction interlayer, and the speaker is fixedly mounted on the speaker mounting plate with the speaker opening facing the micro-perforated sound-absorbing plate.

8. The barrier system according to claim 7, characterized in that, The speaker mounting plate is fixedly connected to the noise reduction interlayer via vibration damping pads.

9. The barrier system according to claim 7 or 8, characterized in that, The detachable bracket includes a support rod, one end of which is connected to the speaker mounting plate via a universal connector that can be limited, and the other end of which is connected to the cage frame via a clamping member.

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