Multi-channel microphone random array
By using a random array of 128 microphones, the problem of insufficient insulator monitoring accuracy in open environments is solved, achieving efficient and accurate data acquisition and processing, reducing costs, adapting to complex environment installations, and improving the practicality of the device.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- 四川铁道职业学院
- Filing Date
- 2025-04-14
- Publication Date
- 2026-04-24
AI Technical Summary
Existing acoustic monitoring methods suffer from environmental limitations in open environments, making them unsuitable for real-time monitoring of insulators in exposed conductors and open field environments.
A multi-channel random array of 128 microphones is used, divided into different microphone sections. It adopts a planar structure and is arranged at a specific angle. Combined with FPGA and RK3588 core board for signal processing, it achieves efficient sampling and data management.
It improves the diversity and accuracy of data acquisition, reduces errors, simplifies wiring, reduces costs, and enables integration and miniaturization, adapting to complex installation environments, and improving data processing speed and device usability.
Smart Images
Figure CN224164877U_ABST
Abstract
Description
Technical Field
[0001] This utility model belongs to the field of sampling technology, specifically relating to a multi-channel microphone random array. Background Technology
[0002] Insulators are special insulating components mainly used in overhead transmission lines to support conductors, increase creepage distances, and isolate high voltage. Because insulators are exposed to the elements without protection, industrial pollutants and airborne particles easily accumulate on their surfaces, forming a contamination layer. In humid weather conditions such as rain or snow, this contamination layer gradually becomes wet, and under the influence of a strong electric field, surface discharge can occur, leading to flashover and potentially causing widespread power outages.
[0003] To reduce power outages caused by contamination buildup on insulator surfaces, railway management departments currently conduct annual surveys of all pollution sources within a 2-kilometer radius. However, this method is time-consuming, labor-intensive, and cannot achieve real-time monitoring. To achieve real-time insulator monitoring, one approach is to monitor related electrical and non-electrical parameters. One method involves acoustic monitoring using multiple ultrasonic sensors installed at different spatial locations on transformers, power cables, GIS equipment, etc., to monitor sound, extract feature values, and then use machine learning and other methods to achieve pattern recognition and fault location of power equipment discharges. However, this method typically uses contact-type sensors, suitable for enclosed, opaque power equipment casings. It is not suitable for exposed conductors or open outdoor environments because the accuracy of sound signal acquisition is affected by the environment. Utility Model Content
[0004] This utility model discloses a multi-channel microphone random array, which aims to solve the technical problem that the sampling accuracy of the existing acoustic monitoring method is affected by the environment and is not suitable for use in open environments.
[0005] To solve the aforementioned technical problems, the present invention adopts the following technical solution:
[0006] A multi-channel microphone random array includes a sampling module, a connection module, and a control module, wherein the sampling module is connected to the control module through the connection module;
[0007] The sampling module includes a random array of 128 microphones. The 128 microphones are divided into several microphone sections, and each microphone section includes several microphones arranged randomly. The sampling module has a planar structure.
[0008] By adopting this technical solution, signal acquisition through 128 microphones can improve the diversity and richness of data acquisition, broadening the scope of collected data and thus enhancing the accuracy and representativeness of the data in subsequent analysis. Simultaneously, dividing the 128 microphones into different microphone sections facilitates the management of data acquired from different microphones, thereby increasing the device's processing speed for data acquired by the microphone array and ultimately improving the device's overall performance during operation.
[0009] The planar microphone array allows each microphone to form a different angle with the discharge surface of the insulator. By measuring the acoustic wave data from different microphones relative to the discharge surface of the insulator, the accumulation of contaminants on the discharge surface can be measured, achieving accurate monitoring of contamination on the insulator's discharge surface. Therefore, the planar microphone array improves the accuracy of the sampled data.
[0010] The 128 microphones are divided into arrays, each array containing several microphone units, and each microphone unit containing an even number of microphones.
[0011] After adopting this technical solution, all microphones are divided into several large groups, and each large group is further divided into multiple microphone sections. This distribution method facilitates the management of all microphones.
[0012] The 128 microphones are divided into two groups, each group containing eight microphone sections, and each microphone section containing eight microphones.
[0013] By adopting this technical solution, the 128 microphones are divided into 2 microphone groups and 16 microphone sections. This distribution method facilitates the management of all microphones, reduces the computational difficulty of the control module while improving data acquisition accuracy, which helps to extend the lifespan of the control module and reduce the operating cost of the device.
[0014] In each microphone section, two microphones share a second signal output terminal, which is connected to the connection module. All microphones in each microphone section share a first signal output terminal and a ground terminal, which are both connected to the connection module. The first signal output terminal is a clock signal output terminal, and the second signal output terminal is a digital signal output terminal.
[0015] By adopting this technical solution, all microphones in each microphone unit share a single clock signal output terminal and ground terminal, reducing the number of ports used on the connection module and thus its size, facilitating the integrated practicality of the device. Simultaneously, one clock signal can control eight microphones at the same time, ensuring the synchronization of microphone sampling. Because the angles and distances of these eight microphones relative to the insulator discharge surface are different, the relevant acoustic wave data collected from the insulator discharge surface will also be different. These eight data points form a relevant reference and can be compared with each other, improving the accuracy of the data and the representativeness of the data from each microphone unit, and reducing the generation of errors.
[0016] The digital signal outputs of the two microphones can be controlled by a single data cable, which reduces the number of data cables used, simplifies the structure of the microphone array, and reduces wiring difficulty.
[0017] The connection module includes an FPGA core board, and the control module includes an RK3588 core board. The FPGA core board and the RK3588 core board transmit signals in series via UDP.
[0018] By adopting this technical solution, through the FPGA core board, RK3588 core board, etc., it is possible to achieve efficient sampling of sound waves, and by setting other module components on the RK3588, other functional module settings can be realized, such as the acquisition and analysis of video and audio information, thereby improving the practicality of this device.
[0019] The 128 microphones are connected to pins on the FPGA core board.
[0020] By adopting this technical solution, 128 microphones are connected to pins at different locations on the FPGA core board, which improves the accuracy of the connection between the pins and the microphones, thereby improving the accuracy of data collection.
[0021] The distance between two adjacent microphones ranges from 14 to 16 mm, and the diameter of the random array ranges from 130 to 170 mm.
[0022] By adopting this technical solution, the distance between microphones and the array range between microphones are limited, effectively integrating and miniaturizing the microphone array. This effectively reduces the overall size of the microphone array, adapts to the installation requirements of complex on-site environments for circuit insulators, reduces costs, and improves economic efficiency.
[0023] In summary, due to the adoption of the above technical solution, the beneficial effects of this utility model are:
[0024] (1) Using a 128-channel microphone random array not only increases the range of data acquisition, but also divides the random array into different microphone sections, which not only provides a comparison of the acquired data, but also increases the data processing speed, ensures the accuracy and representativeness of the data, and reduces errors.
[0025] (2) A random array with a planar structure is used so that each microphone forms a different angle with the conductive surface of the insulator, and different sound wave signals are measured, so that the data support each other and are compared with each other, thereby improving the accuracy of the data.
[0026] (3) The use of a first signal output terminal, a second signal output terminal, etc., simplifies the layout of the line and reduces the difficulty of the line layout while ensuring the data processing rate, thus reducing costs.
[0027] (4) By using FPGA core board, RK3588 core board, etc., it can not only achieve efficient sampling of sound waves, but also set other functional modules by setting other module components of RK3588, such as the acquisition and analysis of video and audio information, thus improving the practicality of the device.
[0028] (5) By setting the range between two adjacent microphones, the distance between microphones and the array range between microphones are limited, and the microphone array is effectively integrated and miniaturized. This can effectively reduce the overall size of the microphone array, adapt to the installation requirements of complex environments in circuit insulators, reduce costs, and improve economic benefits. Attached Figure Description
[0029] This utility model will be described by way of example and with reference to the accompanying drawings, wherein:
[0030] Figure 1 This is a frame diagram of a multi-channel microphone random array according to the present invention;
[0031] Figure 2 A planar layout diagram of a random array of microphones;
[0032] Figure 3 Schematic diagram of a random array circuit for a 128-channel microphone;
[0033] Figure 4 This is a circuit diagram of a microphone unit.
[0034] Figure 5 The diagram shows the connection between the 128-channel microphone array and the FPGA core board, where (a) is the connection diagram of the first group with the FPGA core board, and (b) is the connection diagram of the second group with the FPGA core board.
[0035] Figure 6Figure 1 shows the connection diagram between the FPGA and the RK3588. Figure 2 shows the location of the corresponding ports on the FPGA core board that are connected to the RK3588, and Figure 3 shows the corresponding ports on the FPGA core board that are connected to the RK3588. Detailed Implementation
[0036] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions in the embodiments of this application will be clearly and completely described below in conjunction with the embodiments and accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of the embodiments. The components of the embodiments of this application described and marked in the accompanying drawings can be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of this application provided in the accompanying drawings is not intended to limit the scope of the claimed application, but merely represents selected embodiments of this application. All other embodiments obtained by those skilled in the art based on the embodiments of this application without inventive effort are within the scope of protection of this application.
[0037] In the description of the embodiments of this application, it should be noted that the terms "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship commonly used when the utility model product is in use. They are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application. In addition, the terms "first," "second," and "third," etc., are only used to distinguish descriptions and should not be construed as indicating or implying relative importance.
[0038] The following is combined with Figures 1-6 This utility model will be described in detail.
[0039] A multi-channel microphone random array, such as Figures 1-6 As shown, it includes a sampling module, a connection module, and a control module, wherein the sampling module is connected to the control module through the connection module;
[0040] The sampling module includes a random array of 128 microphones. The 128 microphones are divided into several microphone sections, and each microphone section includes several microphones arranged randomly. The sampling module has a planar structure.
[0041] In this embodiment, the microphone is a MEMS silicon microphone, which has advantages such as small size, high performance, and low power consumption. The basic principle of a MEMS microphone is to integrate an equivalent capacitor formed by a diaphragm and a backplate onto a micro-silicon wafer. A fixed voltage is applied to the diaphragm, giving the capacitor an initial capacitance value. When sound pressure acts on the MEMS diaphragm, it vibrates, causing a change in capacitance. This change is then amplified by the ASIC stage to become the microphone's output.
[0042] In this embodiment, the sampling frequency of the microphone is 20Hz-80KHz, and the effective distance can reach up to 50 meters.
[0043] In this embodiment, as Figure 4 The diagram shows the microphone's circuit schematic. Terminal 1 outputs a PDM digital signal, and terminal 4 outputs a clock signal.
[0044] In this embodiment, the distance between the microphone random array and the insulator is 2m.
[0045] By acquiring signals through 128 microphones, the diversity and richness of data collection can be improved, resulting in a wider range of collected data and thus enhancing the accuracy and representativeness of the data in subsequent analysis. Simultaneously, dividing the 128 microphones into different microphone sections facilitates the management of data acquired from different microphones, thereby increasing the device's processing speed for data acquired by the microphone array and ultimately improving the device's overall performance during operation.
[0046] The planar microphone array allows each microphone to form a different angle with the discharge surface of the insulator. By measuring the acoustic wave data from different microphones relative to the discharge surface of the insulator, the accumulation of contaminants on the discharge surface can be measured, achieving accurate monitoring of contamination on the insulator's discharge surface. Therefore, the planar microphone array improves the accuracy of the sampled data.
[0047] In this embodiment, the 128 microphones are divided into arrays, each array containing several microphone units, and each microphone unit containing an even number of microphones.
[0048] Divide all microphones into several large groups, and each large group is further divided into multiple microphone sections. This distribution method facilitates the management of all microphones.
[0049] In this embodiment, as Figure 4 , Figure 5 As shown, the 128 microphones are divided into two groups, each group containing eight microphone sections, and each microphone section containing eight microphones.
[0050] The 128 microphones are divided into 2 microphone groups and 16 microphone sections. This distribution method facilitates the management of all microphones, improves data acquisition accuracy, reduces the computational complexity of the control module, extends the lifespan of the control module, and reduces the operating cost of the device.
[0051] In this embodiment, each microphone in each microphone unit shares a second signal output terminal with each other. The second signal output terminals are all connected to the connection module. All microphones in each microphone unit share a first signal output terminal and a ground terminal. The first signal output terminal and the ground terminal are both connected to the connection module. The first signal output terminal is a clock signal output terminal, and the second signal output terminal is a digital signal output terminal.
[0052] That is, all microphones in each microphone section share a single clock signal output terminal and ground terminal, which reduces the number of ports used on the connection module, reduces the size of the connection module, and facilitates the integrated and practical use of this device.
[0053] At the same time, a clock signal can control 8 microphones simultaneously, ensuring the synchronization of microphone sampling. Because the angles and distances of these 8 microphones relative to the discharge edge of the insulator are different, the relevant acoustic wave data collected from the discharge edge of the insulator are also different. These 8 data not only form a relevant reference, but also compare with each other, improving the accuracy of the data and the representativeness of the data from each microphone, and reducing the generation of errors.
[0054] The digital signal outputs of the two microphones can be controlled by a single data cable, which reduces the number of data cables used, simplifies the structure of the microphone array, and reduces wiring difficulty.
[0055] In this embodiment, as Figure 1 As shown, the connection module includes an FPGA core board, and the control module includes an RK3588 core board. The FPGA core board and the RK3588 core board transmit signals in series via UDP.
[0056] In this embodiment, the RK3588 core board is designed with a high-performance processor, featuring a quad-core ARM Cortex-A76 with a main frequency of up to 2.4 GHz and a quad-core ARM Cortex-A55 with a main frequency of up to 1.8 GHz, and a sampling rate of up to 192 kHz.
[0057] By using the FPGA core board and RK3588 core board, efficient sampling of sound waves can be achieved. Furthermore, by configuring other modules on the RK3588, other functional modules can be configured, such as the acquisition and analysis of video and audio information, thereby improving the practicality of this device.
[0058] In this embodiment, as Figure 5As shown, the 128 microphones are connected to pins on the FPGA core board.
[0059] In this embodiment, 128 microphones are connected to pins on the FPGA core board via leads.
[0060] In this embodiment, as Figure 6 As shown, the FPGA core board is equipped with a GMAC interface, such as... Figure 5 As shown, it connects to the RK3588 core board via the GMAC interface, as follows. Figure 6 As shown.
[0061] In this embodiment, as Figure 4 , Figure 5 As shown, the FPGA core board has 50 interfaces at each end. Each end has 8 GND interfaces, 8 PDM_CLK pins and 32 PDM_DAT pins. Each PDM_DAT pin is connected in parallel with 2 microphones. The 8 microphones form a unit, and each unit shares one GND pin and one PDM_CLK pin.
[0062] In this embodiment, the microphone random array is set on an array board, which has a four-layer structure: layers 1 and 3 are for wiring, layer 2 is +3.3V, and layer 4 is GND.
[0063] In this embodiment, as Figure 5 and Figure 6 As shown, the FPGA core board has a total of 154 interfaces, of which 128 are used by the microphone random array.
[0064] The 128 microphones are connected to pins at different locations on the FPGA core board, which improves the accuracy of the connection between the pins and the microphones, thereby improving the accuracy of data collection.
[0065] In this embodiment, as Figure 2 As shown, the distance between two adjacent microphones ranges from 14 to 16 mm, and the diameter of the random array ranges from 130 to 170 mm.
[0066] In this embodiment, the distance between two adjacent microphones is 15mm, the diameter of the random array is 150mm, and the shape of the random array is circular. The circular structure can be used in conjunction with other modules and can also reduce the area of the random array.
[0067] In this embodiment, it should be noted that when the distance between the receiving point and the transmitting point is greater than twice the far-field boundary, it can be considered to be in the far-field distance. That is, in this utility model, if the wavelength is... Given that the microphone spacing is d and the speed of sound is c, the distance s from the discharge location to the center of the array can be roughly estimated using the following formula. It should be noted that this formula is an existing one:
[0068]
[0069] In this embodiment, to ensure that the 128 microphones are located within a circle with a diameter of 150mm on the array plate and at a far-field distance, the spacing between two adjacent microphones is chosen to be 15mm. Through extensive field experiments and analysis of the ultrasonic characteristics of surface discharge of railway insulators, it was found that the ultrasonic signal of surface discharge of insulators is mainly distributed within the range of 25kHz±3kHz. Therefore, taking the speed of sound c as 340m / s and d as 15mm, we can obtain s = 3.7x10 4 It is much larger than the microphone distance from the insulator of 2000mm, thus ensuring that the microphone distribution area is within a circle with a diameter of 150mm and located at the far field distance.
[0070] The specific method of using this utility model is as follows:
[0071] Reference Figures 1-6 When using this device, first install it 2 meters away from the insulator. After installation, start the device. Each microphone on the device forms a different angle with the discharge surface of the insulator, and performs sound monitoring and sampling at different positions along the discharge surface. The sampled information is transmitted to the FPGA core board through a random microphone array. The FPGA core board then transmits the data to the RK3588 core board via UDP. The RK3588 core board then analyzes and processes the collected data and transmits the processed data to other modules to determine the contaminant adhesion status along the discharge surface of the insulator, thereby alerting maintenance personnel to the specific location of the fault, facilitating maintenance, improving maintenance speed, reducing the waste of manpower and resources, and creating higher economic value.
[0072] The above description of the disclosed embodiments enables those skilled in the art to make or use the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.
Claims
1. A multi-channel microphone random array, characterized in that: It includes a sampling module, a connection module, and a control module, wherein the sampling module is connected to the control module through the connection module; The sampling module includes a random array of 128 microphones. The 128 microphones are divided into several microphone sections, and each microphone section includes several microphones arranged randomly. The sampling module has a planar structure.
2. The multi-channel microphone random array according to claim 1, characterized in that: The 128 microphones are divided into arrays, each array containing several microphone units, and each microphone unit containing an even number of microphones.
3. A multi-channel microphone random array according to claim 2, characterized in that: The 128 microphones are divided into two groups, each group containing eight microphone sections, and each microphone section containing eight microphones.
4. A multi-channel microphone random array according to claim 3, characterized in that: Each microphone in each microphone unit shares a second signal output terminal with each other. The second signal output terminals are all connected to the connection module. All microphones in each microphone unit share a first signal output terminal and a ground terminal. The first signal output terminal and the ground terminal are both connected to the connection module. The first signal output terminal is a clock signal output terminal, and the second signal output terminal is a digital signal output terminal.
5. A multi-channel microphone random array according to any one of claims 1-4, characterized in that: The connection module includes an FPGA core board, and the control module includes an RK3588 core board. The FPGA core board and the RK3588 core board transmit signals in series via UDP.
6. A multi-channel microphone random array according to claim 5, characterized in that: The 128 microphones are respectively connected to pins on the FPGA core board.
7. A multi-channel microphone random array according to any one of claims 1-4, characterized in that: The distance between two adjacent microphones ranges from 14 to 16 mm, and the diameter of the random array ranges from 130 to 170 mm.