A portable high-fidelity remote pickup

Abstract

The utility model discloses a portable high-fidelity remote microphone, which belongs to the field of microphone technology; it includes a shell; a microphone array acquisition board is arranged in the shell; a plurality of identical electret microphones are arranged on the microphone array acquisition board, and the plurality of electret microphones are linearly and evenly distributed; the microphone array acquisition board is connected to an electronic circuit board, and the microphone array acquisition board can collect sound information and spatial position information of the sound, and convert it into an electrical signal and transmit it to the electronic circuit board. The utility model has a simple structure and is easy to use. The sound pickup distance can reach 30m. The electronic circuit board can process far-field audio signals to ensure high-fidelity audio output; the utility model can pick up high-fidelity and high-definition sound signals under far-field conditions.

Description

Technical Field

[0001] The utility model belongs to the technical field of microphones and relates to a portable high-fidelity remote microphone. Background Art

[0002] Microphones are widely used, and their main working principle is to convert sound signals into electrical signals. In classrooms, lecture halls, concert halls and other scenes, people in the front row can use the microphones currently on the market to obtain better voice or audio signals, while it is difficult for people in the back row to obtain better voice or audio signals through the microphones on the market. The fundamental reason for this phenomenon is that the microphones used in the existing microphones on the market are all close-range microphones, and the sound that can be received is limited to a small range, so the application is limited. If you want to collect the sound of interest at a long distance and let people hear it clearly, it is difficult to achieve.

[0003] However, there are many scenarios that require remote sound pickup, such as military long-distance monitoring, long-distance observation of animals, and people sitting at the back in classrooms, lecture halls, concert halls, etc. Therefore, it is urgent to develop a high-fidelity remote sound pickup that can remotely pick up sound in a directional manner, amplify very weak signals, and has certain intelligent operations. Utility Model Content

[0004] The utility model aims to provide a portable high-fidelity long-distance microphone pickup to solve the technical problems of short sound pickup distance and low fidelity of the microphone pickup in the prior art.

[0005] In order to achieve the above purpose, the utility model adopts the following technical solutions:

[0006] The utility model provides a portable high-fidelity remote pickup, comprising a shell; a microphone array acquisition board is arranged in the shell; a plurality of identical electret microphones are arranged on the microphone array acquisition board, and the plurality of electret microphones are linearly and evenly distributed; the microphone array acquisition board is connected to an electronic circuit board, and the microphone array acquisition board can collect sound information and spatial position information of the sound, and convert them into electrical signals and transmit them to the electronic circuit board.

[0007] Furthermore, an MCU microcontroller chip is provided on the electronic circuit board, and the MCU microcontroller chip is respectively connected to a DSP chip, a cache chip, a Bluetooth chip, a power management chip and a D / A chip; the power management chip is connected to a battery; the D / A chip is connected to an audio port; and the cache chip and the MCU microcontroller chip are both connected to a microphone array acquisition board.

[0008] Furthermore, the microphone array acquisition board is also provided with two A / D chips, and the A / D chips are used to convert analog signals into digital signals and transmit them to the cache chip.

[0009] Furthermore, one side of the MCU microcontroller chip is provided with a volume button, a collection button, a power button, a USB interface, an SD card slot and an LED indicator light in sequence.

[0010] Furthermore, the battery is a 0805 lithium battery.

[0011] Furthermore, a soundproof cover is provided on the plurality of electret microphones.

[0012] Furthermore, a waterproof and sound-permeable membrane is provided between the microphone array collection board and the housing.

[0013] Furthermore, the shell includes a top shell and a bottom shell; the top shell and the bottom shell are fixedly connected to form the shell; a plurality of pickup holes corresponding to the positions of the electret microphones are opened on the top shell, and a steel mesh is installed in the pickup holes.

[0014] Furthermore, the fixed connection between the top shell and the bottom shell is a threaded connection.

[0015] Furthermore, the housing is made of plastic.

[0016] Compared with the prior art, the utility model has the following beneficial effects:

[0017] The utility model discloses a portable high-fidelity remote sound pickup. A microphone array acquisition board is arranged in the sound pickup shell. The microphone array acquisition board collects sound information and spatial position information of the sound, and converts them into electrical signals and transmits them to an electronic circuit board for processing. The utility model has a simple structure and is easy to use. The sound pickup distance can reach 30m. The electronic circuit board can process far-field audio signals to ensure high-fidelity audio output. In addition, the utility model is provided with a plurality of linearly evenly distributed electret microphones, which can collect sound signals of interest to users and spatial position information of the sound, provide more data information for the electronic circuit board, and provide assistance for high-fidelity sound quality output. Therefore, the utility model can pick up high-fidelity and high-definition sound signals under far-field conditions.

[0018] Furthermore, a soundproof cover is provided on the electret microphone of the utility model, which can prevent the sound signal from being reflected inside the shell on the one hand, and reduce the influence of wind flow noise on the sound pickup performance on the other hand.

[0019] Furthermore, a waterproof and sound-permeable membrane is provided between the microphone array collection board and the housing of the utility model, which can play a role of waterproof and sound-permeable. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to more clearly illustrate the technical solutions of the embodiments of the utility model, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the utility model and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other relevant drawings can be obtained based on these drawings without paying creative work.

[0021] Figure 1 This is a structural diagram of the pickup of the embodiment of the utility model;

[0022] Figure 2 This is a working principle diagram of the pickup of the utility model embodiment;

[0023] Figure 3 This is a flowchart of the algorithm processing of the microphone DSP chip in the embodiment of the utility model.

[0024] Among them: 1-top shell; 2-waterproof sound-permeable membrane; 3-M2 self-tapping screws; 4-battery; 5-sound insulation cover; 6-microphone array acquisition board; 7-USB interface; 8-battery indicator light; 9-recording storage indicator light; 10-bottom shell; 11-M2.6 self-tapping screws; 12-SD card slot; 13-recording button; 14-power button; 15-copper studs; 16-M2.6 machine screws; 17-electret microphone; 18-plastic button; 19-electronic circuit board. DETAILED DESCRIPTION

[0025] In order to make the purpose, technical scheme and advantages of the embodiments of the utility model clearer, the technical scheme in the embodiments of the utility model will be clearly and completely described below in conjunction with the drawings in the embodiments of the utility model. Obviously, the described embodiments are part of the embodiments of the utility model, not all of the embodiments. Generally, the components of the embodiments of the utility model described and shown in the drawings here can be arranged and designed in various different configurations.

[0026] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the present invention to be protected, but merely represents selected embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0027] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, further definition and explanation thereof is not required in subsequent drawings.

[0028] In the description of the embodiments of the present utility model, it should be noted that if the terms "upper", "lower", "horizontal", "inner", etc. indicate an orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship in which the utility model product is usually placed when in use, it is only for the convenience of describing the utility model and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present utility model. In addition, the terms "first", "second", etc. are only used to distinguish the description, and cannot be understood as indicating or implying relative importance.

[0029] In addition, if the term "horizontal" appears, it does not mean that the component must be absolutely horizontal, but can be slightly tilted. For example, "horizontal" only means that its direction is more horizontal than "vertical", which does not mean that the structure must be completely horizontal, but can be slightly tilted.

[0030] In the description of the embodiments of the present utility model, it is also necessary to explain that, unless otherwise clearly specified and limited, the terms "set", "install", "connect", and "connect" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present utility model can be understood according to specific circumstances.

[0031] The utility model is further described in detail below with reference to the accompanying drawings:

[0032] See also Figure 1 The embodiment of the utility model discloses a portable high-fidelity remote microphone, including a shell, which is made of a flame-retardant, drop-proof plastic material with electromagnetic interference shielding function; a microphone array acquisition board 6 is arranged in the shell; a plurality of identical electret microphones 17 are arranged on the microphone array acquisition board 6, and the plurality of electret microphones 17 are linearly and evenly distributed. Although a single microphone can collect the sound at the sound source when in use, it cannot collect the spatial position information of the sound. Therefore, the microphone of the utility model adopts the microphone array acquisition board 6, which can collect the sound signal of interest to the user and the spatial position information of the sound, and provide more data information for the DSP chip in the electronic circuit board 19; the microphone array acquisition board 6 is connected to the electronic circuit board 19, and the microphone array acquisition board 6 can collect sound information and the spatial position information of the sound, and convert them into electrical signals and transmit them to the electronic circuit board 19.

[0033] In a feasible implementation of the present invention, see Figure 2, the electronic circuit board 19 is provided with an MCU micro-control chip, which is respectively connected to the DSP chip, cache chip, Bluetooth chip, power management chip and D / A chip; the power management chip is connected to the battery 4, and the battery 4 preferably adopts a 0805 rechargeable 2600mAh lithium battery to provide long-term battery life for the normal operation of the pickup. The D / A chip is connected to the audio port; the cache chip and the MCU micro-control chip are both connected to the microphone array acquisition board 6, and the microphone array acquisition board 6 mainly converts the sound signal into a weak electrical signal through the electret microphone 17 and amplifies it through the preamplifier circuit. The amplified signal passes through the A / D chip and undergoes secondary amplification processing, and finally transmits the signal to the DSP chip in the electronic circuit board 19. One side of the MCU micro-control chip is also provided with a volume button, a collection button, a power button 14, a USB interface 7, an SD card slot 12, and an LED indicator light. It should be noted that the function of the MCU microcontroller chip is to control and manage the various chips, devices and I / O ports on the electronic circuit board 19; the main function of the cache chip is to cache the sound signals collected by the microphone array acquisition board 6, and the cached signals are transmitted to the DSP chip after pre-filtering; the DSP chip mainly performs algorithm processing on the signals transmitted from the cache chip. In the utility model, the algorithms contained in the DSP chip mainly include beamforming algorithm and speech noise reduction algorithm. The signals after algorithm processing are distributed to various I / O ports on the electronic circuit board 19 after being controlled by the MCU microcontroller chip; the main function of the D / A conversion chip is to convert the digital signal processed by the DSP into an analog signal, and finally transmit the analog signal to the audio port, which can be monitored in real time after connecting the headphones; the Bluetooth chip mainly plays the role of connecting and interacting with mobile terminals such as mobile phones in the pickup described in the utility model; the power management chip mainly manages, distributes and detects the power required for the operation of various components on the electronic circuit board 19 and the microphone array acquisition board 6. The SD card slot is mainly used to place an SD memory card, which is used to store the original data collected by the pickup and the data processed by the algorithm, which is convenient for secondary development; the utility model is also provided with an audio port, which is a 3.5mm audio mother port, which is used to connect headphones and can monitor the sound to be collected in real time; the USB interface has three main functions: first, the running version of the pickup can be corrected or upgraded; second, the data in the pickup SD card can be read and written; finally, the battery of the pickup can be charged. The LED indicator light is mainly used to indicate the working, charging, collection, abnormal and other conditions of the pickup, which is convenient for use. Preferably, a power indicator light 8 and a recording storage indicator light 9 can be set, and a recording button 13 can be set. In this embodiment, a plastic button 18 can be used on the recording button 13 and the power button 14, which is light in weight, low in cost and good in durability.

[0034] In a feasible implementation of the utility model, the microphone array acquisition board 6 is also provided with two A / D chips, the microphone converts the collected sound signal into a weak electrical signal, and amplifies it through the preamplifier circuit, and the amplified electrical signal is converted from analog to digital through the A / D chip, and amplified twice in parallel. The amplified digital signal is transmitted to the cache chip of the electronic circuit board 19 through the McASP_Ax interface and preprocessed.

[0035] In a feasible implementation of the utility model, a soundproof cover 5 is provided on the plurality of electret microphones 17, which can prevent the sound signal from being reflected inside the housing and reduce the influence of wind noise on the sound pickup performance. A waterproof and sound-permeable membrane 2 is provided between the microphone array acquisition board 6 and the housing, and is tightly connected by M2 self-tapping screws 3.

[0036] In a feasible implementation manner of the utility model, the outer shell includes a top shell 1 and a bottom shell 10; the top shell 1 and the bottom shell 10 are threadedly connected to form the outer shell, preferably using M2.6 self-tapping screws 11; a plurality of pickup holes corresponding to the positions of the electret microphones 17 are opened on the top shell 1, and a steel mesh is installed in the pickup holes, and the microphone array acquisition board 6 is connected to the bottom shell 10 by copper studs 15 and M2.6 machine screws 16.

[0037] The working principle of the utility model DSP chip is as follows:

[0038] See also Figure 3 The main function of the DSP chip is to process the signal transmitted from the data cache unit: filtering, overlapping framing and windowing, short-time Fourier transform, beamforming algorithm processing, noise reduction algorithm processing, short-time Fourier inverse transform, windowing and overlapping summation, and finally obtain the desired signal. Specifically, the following steps are included:

[0039] Step 1: Filtering. The DSP receives the pre-processed noisy speech signal and performs filtering on the noisy speech signal. For example, a high-pass filter is used to attenuate and suppress the noisy speech signal components below 204 Hz, while passing the noisy speech signal components above 204 Hz.

[0040] Step 2: Overlapping framing and windowing. Speech signals are not stable at the macro level, but approximately stable at the micro level. Speech signals have short-term stability. Specifically, speech signals are approximately unchanged within 30ms. Therefore, speech signals can be divided into several short segments for processing, that is, framing operations, and each short segment is called a frame. In order to prevent the pitch from changing between two adjacent frames, such as framing between two syllables, or framing when the initial consonant is transitioning to the final, in this case, the characteristic parameters of the speech signal may change greatly. In order to make the characteristic parameters of the speech signal change smoothly, one or more frames are inserted between two non-overlapping frames, so that overlap is formed between adjacent frames. The time difference between the starting positions of two adjacent frames is called frame shift. In order to reduce the truncation effect of speech frames, windowing processing is required. Commonly used window functions include rectangular window, Hamming window, Hanning window, Kaiser window, etc. The purpose of windowing is twofold: on the one hand, it makes the speech signal more continuous globally and avoids the Gibbs effect, i.e., the truncation effect; on the other hand, the speech signal, which originally has no periodicity, exhibits some characteristics of a periodic function;

[0041] Step 3: Short Time Fourier Transform (STFT). Short Time Fourier Transform is a common tool in speech signal processing. Here, it mainly performs Fourier transform on the overlapping framed and windowed speech signals. It defines a very useful time and frequency distribution class, which specifies the complex amplitude of any signal changing with time and frequency, namely the Fourier spectrum.

[0042] Step 4: Beamforming algorithm processing. Through the above steps, a short-term stable speech signal can be obtained. On this basis, the beamforming algorithm processes each frame of the multi-channel speech signal. After the beamforming algorithm is processed, a single-channel frequency domain speech signal in the desired direction will be obtained;

[0043] Step 5: Noise reduction algorithm processing. The main function of the noise reduction algorithm is to perform frequency domain noise reduction processing on the signal processed by the beamforming algorithm, further improving the signal-to-noise ratio and intelligibility of the speech signal;

[0044] Step 6: Inverse Short Time Fourier Transform (ISTFT). The process of inverse short time Fourier transform is the inverse process of short time Fourier transform. Here, it mainly converts the speech signal processed by the beamforming algorithm from the frequency domain to the time domain;

[0045] Step 7: Windowing and Overlap-Add. The function of windowing and overlap-add is to splice the discrete speech signal after the short-time Fourier inverse transform, which corresponds to the above step 2, i.e., overlapping framing and windowing, to reduce the distortion caused by the signal transformation from the frequency domain to the time domain. The output signal after overlap-add is the time domain signal expected by the utility model, i.e., the time domain speech signal after the beamforming algorithm processing.

[0046] The above is the working principle of the DSP chip in the electronic circuit board 19 of the present invention. It should be noted that the algorithm in the DSP chip of the present invention is a mature algorithm in the prior art, and the present invention does not improve it.

[0047] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. For those skilled in the art, the present invention may be subject to various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A portable high-fidelity remote microphone, characterized in that: The invention comprises a shell; a microphone array acquisition board (6) is arranged in the shell; a plurality of identical electret microphones (17) are arranged on the microphone array acquisition board (6), and the plurality of electret microphones (17) are linearly and evenly distributed; the microphone array acquisition board (6) is connected to an electronic circuit board (19), and the microphone array acquisition board (6) can collect sound information and spatial position information of sound, and convert the information into electrical signals and transmit them to the electronic circuit board (19).

2. A portable high-fidelity remote microphone according to claim 1, characterized in that: The electronic circuit board (19) is provided with an MCU micro-control chip, and the MCU micro-control chip is respectively connected to a DSP chip, a cache chip, a Bluetooth chip, a power management chip and a D / A chip; the power management chip is connected to a battery (4); the D / A chip is connected to an audio port; and the cache chip and the MCU micro-control chip are both connected to a microphone array acquisition board (6).

3. A portable high-fidelity remote microphone according to claim 2, characterized in that: The microphone array acquisition board (6) is also provided with two A / D chips, and the A / D chips are used to convert analog signals into digital signals and transmit them to the cache chip.

4. A portable high-fidelity remote microphone according to claim 2, characterized in that: One side of the MCU microcontroller chip is also provided with a volume button, a collection button, a power button (14), a USB interface (7), an SD card slot (12) and an LED indicator light in sequence.

5. A portable high-fidelity remote pickup according to claim 2, characterized in that: The battery (4) is a 0805 lithium battery.

6. A portable high-fidelity remote microphone according to claim 1, characterized in that: A soundproof cover (5) is provided on the plurality of electret microphones (17).

7. A portable high-fidelity remote microphone according to claim 1, characterized in that: A waterproof and sound-permeable membrane (2) is provided between the microphone array collection board (6) and the housing.

8. The portable high-fidelity remote microphone according to claim 1, characterized in that: The outer shell comprises a top shell (1) and a bottom shell (10); the top shell (1) and the bottom shell (10) are fixedly connected to form the outer shell; a plurality of sound pickup holes corresponding to the positions of the electret microphones (17) are provided on the top shell (1), and a steel mesh is installed in the sound pickup holes.

9. A portable high-fidelity remote microphone according to claim 8, characterized in that: The fixed connection between the top shell (1) and the bottom shell (10) is a threaded connection.

10. The portable high-fidelity remote microphone according to claim 1, characterized in that: The housing is made of plastic.

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