Vector microphone with high directivity

Abstract

The invention relates to the technical field of acoustic measurement, and discloses a vector microphone with high directivity, which comprises a mounting shell, a circuit board is arranged on the inner side of the mounting shell, and a first particle vibration velocity sensor and a first sound pressure sensor are arranged on the side surface of the top of the circuit board. The first mass point vibration velocity sensor and the first sound pressure sensor form an A group of vector microphones, and a second mass point vibration velocity sensor and a second sound pressure sensor are arranged on the side face of the middle of the circuit board. The first particle vibration velocity sensor and the first sound pressure sensor which are arranged on the circuit board form an A group of vector microphones, and the second particle vibration velocity sensor and the second sound pressure sensor which are arranged on the circuit board form a B group of vector microphones, so that the vector microphones have high directivity; the environmental noise can be suppressed to a greater extent, so that the sound in the target direction can be picked up more clearly, and higher environmental noise suppression capability can be achieved in a recording or industrial acoustic detection scene.

Description

Technical Field

[0001] The invention belongs to the technical field of acoustic measurement, and in particular relates to a vector microphone with high directivity. Background Art

[0002] Microphones are used to detect sound wave signals and convert them into electrical signals. From diaphragm microphones with increasingly higher performance and more diverse forms to extremely small and widely used MEMS (micro-electromechanical systems) microphones, the development of these technologies has promoted the progress of acoustics. In the development of microphone technology, the measurement of acoustic space information has always been a challenge, especially as the application scenarios of technologies such as sound source localization, speech enhancement, and sound intensity measurement are becoming more and more extensive and important. Microphones that can only pick up sound signals in a non-directional manner are gradually unable to meet such needs. Against this background, the emergence of MEMS vector microphones that can measure particle velocity has brought a breakthrough. Ordinary scalar sound pressure sensors can only pick up sound pressure signals in a non-directional manner. As a new type of acoustic sensor, particle velocity sensors can be combined with sound pressure sensors to directly and synchronously measure the sound pressure and particle velocity vector x, y, and z axial components in the Cartesian coordinate system at the same point in the sound field.

[0003] In actual application scenarios, we need higher directivity to pick up the target sound and suppress the ambient noise in other directions to the greatest extent. For example, when recording in a noisy environment, the microphone (also called a microphone) needs to be able to pick up only our voice and filter out the ambient noise; another scenario is that acoustic testing in a factory also needs to be able to suppress the noise in the factory environment as much as possible and pick up the sound emitted by the target test piece more clearly.

[0004] However, the vector microphone is generally composed of a hot-wire particle velocity sensor and a sound pressure sensor. The particle velocity has an "8"-shaped directivity, while the sound pressure has an omnidirectional directivity. The combination of the two can achieve a cardioid-like directivity. Since the cardioid microphone has weak directivity, it can only significantly suppress the back sound, but has weak ability to suppress the lateral sound. This directivity is not sufficient to meet the scene requirements in actual sound field measurements.

[0005] In view of this, the present invention is proposed. Summary of the invention

[0006] In order to solve the problem that the cardioid microphone has weak directivity, can only significantly suppress the back sound, and has weak ability to suppress the lateral sound, and this directivity is not enough to meet the scene requirements in actual sound field measurement, the basic concept of the technical solution adopted by the present invention is:

[0007] A vector microphone with high directivity comprises a mounting shell, a circuit board is arranged on the inner side of the mounting shell, a first particle velocity sensor and a first sound pressure sensor are arranged on the top side of the circuit board, the first particle velocity sensor and the first sound pressure sensor constitute a group A of vector microphones, a second particle velocity sensor and a second sound pressure sensor are arranged on the middle side of the circuit board, the second particle velocity sensor and the second sound pressure sensor constitute a group B of vector microphones.

[0008] As a preferred embodiment of the present invention, the top side surface and the middle side surface of the installation shell are both hollowed out.

[0009] As a preferred embodiment of the present invention, a mounting base is installed on the inner side of the bottom of the mounting shell, a mounting groove is opened on the top of the mounting base, and the bottom of the circuit board is inserted into the inner side of the mounting groove.

[0010] As a preferred implementation of the present invention, a signal acquisition and transmission module and a power circuit module are provided on one side of the bottom of the circuit board, and the power circuit module is located below the signal acquisition and transmission module.

[0011] As a preferred embodiment of the present invention, a connector is disposed at the bottom of the installation housing, and the connector is connected to the power circuit module via a wire.

[0012] As a preferred embodiment of the present invention, a mounting plate is fixedly provided on the outer wall of the bottom end of the mounting shell, and mounting holes arranged equidistantly are opened on the mounting plate.

[0013] As a preferred embodiment of the present invention, an end cover is installed at the top end of the installation shell, and the end cover is detachable.

[0014] Compared with the prior art, the present invention has the following beneficial effects:

[0015] In the present invention, a group A of vector microphones is formed by a first particle velocity sensor and a first sound pressure sensor arranged on a circuit board, and a group B of vector microphones is formed by a second particle velocity sensor and a second sound pressure sensor arranged on the circuit board, so that the present invention has two groups of vector microphones, and each group of vector microphones is composed of a sound pressure sensor and a particle velocity sensor. The output signals of the sensors in the two groups of vector microphones are calculated, and the particle velocity signal of the first particle velocity sensor and the sound pressure of the first sound pressure sensor in the group A of vector microphones are multiplied by a coefficient of 1, respectively, while the particle velocity signal of the second particle velocity sensor and the sound pressure of the second sound pressure sensor in the group B of vector microphones are multiplied by a coefficient of -1, respectively. Thereafter, the four-way sensor signals are added to obtain a signal output, so that the vector microphone has high directivity and can suppress ambient noise to the greatest extent, thereby picking up the sound in the target direction more clearly, and can have a higher ambient noise suppression capability in recording or industrial acoustic detection scenarios.

[0016] The specific implementation modes of the present invention are further described in detail below in conjunction with the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In the attached picture:

[0018] Figure 1 A schematic diagram showing a comparison between the mounting housing structures of a vector microphone with high directivity of the present invention and a vector microphone in the prior art;

[0019] Figure 2 A schematic diagram showing a comparison of the cross-sectional structures of the mounting housings of the vector microphone with high directivity of the present invention and the vector microphone of the prior art;

[0020] Figure 3 A schematic diagram showing a comparison of the cross-sectional structures of the mounting bases of the vector microphone with high directivity of the present invention and the vector microphone of the prior art;

[0021] Figure 4 A directivity diagram of a vector microphone with high directivity according to the present invention;

[0022] Figure 5 A schematic diagram of a method for calculating an output signal of a vector microphone with high directivity according to the present invention;

[0023] Figure 6 It is a schematic diagram of the "8"-shaped directivity of a particle velocity sensor in a vector microphone in the prior art;

[0024] Figure 7 Schematic diagram of the cardioid directivity obtained by adding sound pressure and particle velocity in a vector microphone in the prior art.

[0025] In the figure: 1. Installation shell; 2. Installation plate; 3. Connector; 4. End cover; 5. Circuit board; 6. Installation base; 7. Installation slot; 8. First particle velocity sensor; 9. First sound pressure sensor; 10. Second particle velocity sensor; 11. Second sound pressure sensor; 12. Signal acquisition and transmission module; 13. Power supply circuit module. DETAILED DESCRIPTION

[0026] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. The following embodiments are used to illustrate the present invention.

[0027] like Figures 1 to 5 Shown

[0028] A vector microphone with high directivity comprises a mounting shell 1, a circuit board 5 is arranged on the inner side of the mounting shell 1, a mounting base 6 is installed on the inner side of the bottom of the mounting shell 1, a mounting groove 7 is opened on the top of the mounting base 6, the bottom of the circuit board 5 is inserted into the inner side of the mounting groove 7, a first particle velocity sensor 8 and a first sound pressure sensor 9 are arranged on the top side of the circuit board 5, the first particle velocity sensor 8 and the first sound pressure sensor 9 constitute a group A of vector microphones, a second particle velocity sensor 10 and a second sound pressure sensor 11 are arranged on the middle side of the circuit board 5, the second particle velocity sensor 10 and the second sound pressure sensor 11 constitute a group B of vector microphones, the first particle velocity sensor 8 and the first sound pressure sensor 11 arranged on the circuit board 5 constitute the group A of vector microphones, and the second particle velocity sensor 10 and the second sound pressure sensor 11 arranged on the circuit board 5 constitute the group B of vector microphones, so that the present scheme has two groups of vector sensors. The invention relates to a vector microphone, and each group of vector microphones is composed of a sound pressure sensor and a particle velocity sensor. The output signals of the sensors in the two groups of vector microphones are calculated, and the particle velocity signal of the first particle velocity sensor 8 and the sound pressure of the first sound pressure sensor 9 in group A of vector microphones are multiplied by a coefficient of 1, and the particle velocity signal of the second particle velocity sensor 10 and the sound pressure of the second sound pressure sensor 11 in group B of vector microphones are multiplied by a coefficient of -1, and then the four-way sensor signals are added to obtain a signal output, so that the vector microphone has high directivity and can suppress environmental noise to a greater extent, so as to pick up the sound in the target direction more clearly. The top side and the middle side of the mounting shell 1 are both hollow designs, so that the parts close to the first particle velocity sensor 8 and the second particle velocity sensor 10 are not blocked by excess material, which can effectively avoid signal interference caused by structural shielding, and is convenient to provide better acoustic performance.

[0029] In a specific embodiment, a signal acquisition and transmission module 12 and a power circuit module 13 are provided on one side of the bottom of the circuit board 5. The power circuit module 13 is located below the signal acquisition and transmission module 12. A plug-in connector 3 is provided at the bottom of the mounting shell 1. The plug-in connector 3 is connected to the power circuit module 13 through a wire. The plug-in connector 3 is plugged into the socket to facilitate power supply to the device. A mounting plate 2 is fixedly provided on the outer wall of the bottom end of the mounting shell 1. The mounting plate 2 is provided with equidistant mounting holes. An end cover 4 is installed at the top position of the mounting shell 1. The end cover 4 is detachable. The detachable end cover 4 facilitates disassembly and assembly of components installed in the mounting shell 1.

[0030] The implementation principle of the vector microphone with high directivity in this embodiment is as follows:

[0031] During specific use, a group A of vector microphones is formed by a first particle velocity sensor 8 and a first sound pressure sensor 9 arranged on the circuit board 5, and a group B of vector microphones is formed by a second particle velocity sensor 10 and a second sound pressure sensor 11 arranged on the circuit board 5, so that the present scheme has two groups of vector microphones, and each group of vector microphones is composed of a sound pressure sensor and a particle velocity sensor. The output signals of the sensors in the two groups of vector microphones are calculated, and the particle velocity signal of the first particle velocity sensor 8 and the sound pressure of the first sound pressure sensor 9 in the group A of vector microphones are multiplied by a coefficient of 1, respectively, while the particle velocity signal of the second particle velocity sensor 10 and the sound pressure of the second sound pressure sensor 11 in the group B of vector microphones are multiplied by a coefficient of -1, respectively. Thereafter, the four-way sensor signals are added to obtain a signal output, so that the present vector microphone has high directivity and can suppress environmental noise to a greater extent, thereby picking up the sound in the target direction more clearly.

[0032] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit the exemplary embodiments according to the present application. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should be understood that when the terms "comprise" and / or "include" are used in this specification, it indicates the presence of features, steps, operations, devices, components and / or combinations thereof.

[0033] It should be noted that the terms "first", "second", etc. in the specification and claims of the present application and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the numbers used in this way can be interchanged where appropriate, so that the embodiments of the present application described herein can be implemented in an order other than those illustrated or described herein, for example.

[0034] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various changes and variations. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A vector microphone with high directivity, comprising a mounting housing (1), characterized in that: A circuit board (5) is arranged on the inner side of the mounting shell (1); a first particle velocity sensor (8) and a first sound pressure sensor (9) are arranged on the top side of the circuit board (5); the first particle velocity sensor (8) and the first sound pressure sensor (9) constitute a group A vector microphone; a second particle velocity sensor (10) and a second sound pressure sensor (11) are arranged on the middle side of the circuit board (5); the second particle velocity sensor (10) and the second sound pressure sensor (11) constitute a group B vector microphone.

2. The vector microphone with high directivity according to claim 1, characterized in that: The top side surface and the middle side surface of the installation shell (1) are both hollow-out designs.

3. The vector microphone with high directivity according to claim 1, characterized in that: A mounting base (6) is installed on the inner side of the bottom of the mounting shell (1), a mounting groove (7) is provided on the top of the mounting base (6), and the bottom of the circuit board (5) is inserted into the inner side of the mounting groove (7).

4. The vector microphone with high directivity according to claim 1, characterized in that: A signal acquisition and transmission module (12) and a power circuit module (13) are provided on one side of the bottom of the circuit board (5); the power circuit module (13) is located below the signal acquisition and transmission module (12).

5. The vector microphone with high directivity according to claim 4, characterized in that: A plug connector (3) is provided at the bottom of the installation housing (1), and the plug connector (3) is connected to a power circuit module (13) via a wire.

6. The vector microphone with high directivity according to claim 1, characterized in that: A mounting plate (2) is fixedly arranged on the outer wall of the bottom end of the mounting shell (1), and mounting holes arranged at equal distances are provided on the mounting plate (2).

7. The vector microphone with high directivity according to claim 1, characterized in that: An end cover (4) is installed at the top end of the installation shell (1), and the end cover (4) is detachable.

Images