Microphone array and mobile terminal

Abstract

The invention discloses a microphone array and a mobile terminal, and the microphone array comprises a housing which is internally provided with a plurality of microphones, and the plurality of microphones form a first microphone part and a second microphone part; the first end face is provided with at least two first pickup holes, and the first pickup holes are communicated with microphones in the first microphone part in a one-to-one correspondence manner; the second end face is provided with at least one second pickup hole, and the second pickup holes are communicated with the microphones in the second microphone part in a one-to-one correspondence manner; the first end face intersects with the second end face, a preset included angle is formed between the extending direction of the first end face and the extending direction of the second end face, and the distance between the at least two adjacent microphones is smaller than half wavelength of response frequency used for beam forming. Compared with the prior art, good space capture performance is achieved with the minimum number of actual microphones, and the method is generally suitable for various modern and traditional beam forming algorithms.

Description

Technical Field

[0001] The present invention relates to the field of communication technology, and in particular to a microphone array and a mobile terminal. Background Art

[0002] With the development of mobile terminals, multiple microphones are usually arranged near the receiver of the mobile terminal for collecting sound signals from different directions. The layout of the microphones is particularly important.

[0003] Microphone arrays are well known, but there has been relatively little research into the optimal configuration for new beamforming algorithms. Traditional beamformers have well-known design rules for them. Traditional beamformers require a large number of microphones to achieve good performance (low noise, narrow beams, frequency-independent beamwidth), so more advanced beamforming algorithms have been developed. However, developers of new algorithms pay little or no attention in determining the best microphone configuration to use with the algorithm, so the actual performance of the algorithm and physical microphone combination may be less than optimal. Summary of the invention

[0004] The object of the present invention is to provide a microphone array and a mobile terminal to solve the technical problems in the prior art, and the array and mobile terminal can provide the best microphone placement positions for most beamforming algorithms.

[0005] In a first aspect, the present invention provides a microphone array, comprising:

[0006] A housing having a plurality of microphones built therein, wherein the plurality of microphones form a first microphone unit and a second microphone unit, wherein the first microphone unit has at least two of the microphones, and the second microphone unit has at least one of the microphones;

[0007] A first end surface formed on one surface of the housing, the first end surface being provided with at least two first sound pickup holes, the first sound pickup holes being connected to the microphones in the first microphone unit in a one-to-one correspondence;

[0008] A second end surface is formed on the other surface of the housing, the second end surface is provided with at least one second sound pickup hole, and the second sound pickup hole is connected to the microphone in the second microphone part in a one-to-one correspondence;

[0009] in:

[0010] The first end surface intersects with the second end surface, an extension direction of the first end surface and an extension direction of the second end surface form a preset angle, and a distance between at least two adjacent microphones is less than half a wavelength of a response frequency for beamforming.

[0011] A microphone array as described above, wherein preferably, along the extension direction of the first end surface, the distance between at least two adjacent microphones in the first microphone section is less than half the wavelength of the response frequency for beamforming;

[0012] and / or,

[0013] Along the extension direction of the second end surface, a distance between at least two adjacent microphones in the second microphone portion is smaller than a half wavelength of a response frequency for beamforming.

[0014] A microphone array as described above, wherein preferably, along the extension direction of the second end surface, the microphone in at least one of the second microphone sections is offset from the first end surface;

[0015] and / or,

[0016] Along the extension direction of the first end surface, the microphone in at least one of the first microphone sections is offset from the second end surface.

[0017] In the microphone array as described above, preferably, a camera module is provided in the housing, and at least one of the microphones is integrated in the camera module.

[0018] In the microphone array as described above, preferably, the microphones in the first microphone unit are all integrated into the camera module.

[0019] A microphone array as described above, wherein preferably, at least two of the microphones in the first microphone section and at least one of the microphones in the second microphone section are coplanar to form a first imaginary plane, and the remaining plurality of microphones are staggered on the first imaginary plane.

[0020] A microphone array as described above, wherein preferably, the first microphone unit has three microphones, the second microphone unit has two microphones, the two microphones in the first microphone unit and the one microphone in the second microphone unit are coplanar to form the first imaginary plane, and the remaining multiple microphones are staggered on the first imaginary plane and are located on the same side of the first imaginary plane.

[0021] In the microphone array as described above, preferably, at least one of the microphones is a non-omnidirectional microphone.

[0022] In the microphone array as described above, preferably, the preset angle is 90°.

[0023] In a second aspect, the present invention provides a mobile terminal including the aforementioned microphone array.

[0024] Compared with the prior art, the present invention arranges multiple microphones in a shell, and the multiple microphones are distributed on two adjacent end surfaces, and the spacing between at least two adjacent microphones is less than half the wavelength of the response frequency used for beamforming, thereby providing a good microphone layout for the beamforming algorithm, achieving good spatial capture performance with a minimum actual number of microphones, and is generally applicable to various modern and traditional beamforming algorithms. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 is a structural schematic diagram of a microphone array of a first embodiment provided by the present invention;

[0026] Figure 2 is a structural schematic diagram of a microphone array of a second embodiment provided by the present invention;

[0027] Figure 3 is a schematic structural diagram of a microphone array of a third embodiment provided by the present invention;

[0028] Figure 4 is a schematic diagram of a beamforming system provided by the present invention.

[0029] Explanation of the reference numerals: 1 - housing, 2 - first microphone part, 3 - second microphone part, 4 - microphone, 5 - first end surface, 6 - first sound pickup hole, 7 - second end surface, 8 - second sound pickup hole, 9 - camera module, 10 - first imaginary surface. DETAILED DESCRIPTION

[0030] The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, but should not be construed as limiting the present invention.

[0031] like Figures 1 to 4 As shown, an embodiment of the present invention provides a microphone array, comprising a housing 1, a first end surface 5 is formed on one surface of the housing 1, and a second end surface 7 is formed on the other surface of the housing 1, wherein:

[0032] The shell 1 has multiple built-in microphones 4 for receiving sound waves. The multiple microphones 4 form a first microphone part 2 and a second microphone part 3. The first microphone part 2 has at least two microphones 4, and the second microphone part 3 has at least one microphone 4. The microphone 4 in the first microphone part 2 is used to receive sound signals arriving in the direction of the first end face 5, and the microphone 4 in the second microphone part 3 is used to receive sound signals arriving in the direction of the second end face 7, thereby realizing the collection of sound signals from different directions.

[0033] In a feasible implementation manner, the microphone 4 in the first microphone section 2 is installed on the first end surface 5. Specifically, at least two first sound pickup holes 6 are provided on the first end surface 5. The number and positions of the first sound pickup holes 6 correspond to the number and positions of the microphones 4 in the first microphone section 2. The first sound pickup holes 6 are connected to the microphones 4 in the first microphone section 2 in a one-to-one manner. External sound waves enter the corresponding microphone 4 from the first sound pickup holes 6 to realize the function of the corresponding microphone 4.

[0034] The microphone 4 in the second microphone section 3 is installed on the second end surface 7. Specifically, at least one second sound pickup hole 8 is provided on the second end surface 7. The number and positions of the second sound pickup holes 8 correspond to the number and positions of the microphones 4 in the second microphone section 3. The second sound pickup holes 8 are connected to the microphones 4 in the second microphone section 3 one by one. External sound waves enter the corresponding microphone 4 from the second sound pickup holes 8 to realize the function of the corresponding microphone 4.

[0035] in:

[0036] The first end face 5 intersects with the second end face 7, and a preset angle is formed between the extension direction of the first end face 5 and the extension direction of the second end face 7, so that a preset angle exists between the microphones 4 of the first microphone part 2 and the second microphone part 3. The value of the preset angle can be determined according to actual conditions. In a feasible implementation manner, the preset angle is 90°, that is, the first end face 5 and the second end face 7 intersect vertically.

[0037] A plurality of microphones 4 located at different positions within the first microphone section 2 and the second microphone section 3 form a microphone array. The installation positions of the microphones 4 are different. Through the interaction of the slight time differences between the sound signals reaching each microphone 4 in the microphone array, the microphone array can obtain better directivity than a single microphone 4, and can separate the sounds generated by each sound source and filter out environmental noise, thereby improving the sound pickup effect and speech recognition effect.

[0038] In order to obtain a better denoising effect, at least two microphones 4 are selected to perform beamforming processing on the sound signal. The microphone 4 in the first microphone part 2 can be selected for beamforming processing, or the microphone 4 in the second microphone part 3 can be selected for beamforming processing, or the microphone 4 in the first microphone part 2 and the second microphone part 3 can be selected for beamforming processing at the same time. There is no limitation here. The beamforming processing can be used to focus the microphone array on the sound source, utilize the directional characteristics of the sound, retain the sound signal in a specific direction, and suppress the noise signals in other directions, thereby improving the signal-to-noise ratio.

[0039] The microphone array used for beamforming can be composed of multiple microphones 4 arranged linearly, or can be composed of multiple microphones 4 arranged on the same end surface, or can be composed of multiple microphones 4 arranged on different end surfaces to form a three-dimensional microphone array, thereby providing a good microphone 4 layout for the beamforming algorithm, achieving good spatial capture performance with a minimum number of actual microphones 4, and is generally applicable to various modern and traditional beamforming algorithms.

[0040] Reference Figure 4 As shown, the beamforming algorithm can be based on a statistical analysis of the spatial characteristics of the input signal, such as cross-correlation, and use parameters derived from the statistical analysis to enhance the signal based on the statistical analysis.

[0041] In a feasible implementation mode, referring to Figure 1 As shown, two microphones 4 are provided in the first microphone part 2, and one microphone 4 is provided in the second microphone part 3. The extension direction of the connection line between the two microphones 4 in the first microphone part 2 is parallel to the length direction of the shell 1. The microphones 4 in the first microphone part 2 and the second microphone part 3 are combined together to form a highly directional microphone array. The formed beam can point to the direction of the sound source to enhance the sound source collection effect, thereby improving the sound pickup effect.

[0042] Furthermore, the spacing between at least two adjacent microphones 4 is less than half the wavelength of the response frequency used for beamforming, thereby controlling the beamforming generated by the microphone 4 within a range that is beneficial to improving the sound collection effect. For example, for music and general purpose recording, the corresponding frequency can be 20 kHz, and for broadband speech, it can also be approximately 8 to 12 kHz.

[0043] Specifically, along the extension direction of the first end surface 5, the distance between at least two adjacent microphones 4 in the first microphone unit 2 is less than half the wavelength of the response frequency for beamforming. This distance is desirable, but it is not strictly required that other microphones 4 in the first microphone unit 2 are also close to this distance limit. For example, referring to Figure 1 As shown, two microphones 4 are arranged in the first microphone unit 2 , and a distance d between the two microphones 4 is smaller than a half wavelength of a response frequency used for beam forming.

[0044] and / or,

[0045] Along the extension direction of the second end surface 7, the distance between at least two adjacent microphones 4 in the second microphone section 3 is less than half the wavelength of the response frequency used for beamforming. This distance is desirable, but it is not strictly required that other microphones 4 in the second microphone section 3 are also close to this distance limit.

[0046] In the embodiment provided in the present application, in order to realize the front-to-back separation, along the extension direction of the second end surface 7, the microphone 4 in at least one second microphone part 3 is offset from the first end surface 5, referring to Figure 1 As shown, there is a distance z between the microphone 4 in the second microphone part 3 closest to the first end surface 5 and the first end surface 5. The value of the distance z can be determined according to actual conditions and is not limited here.

[0047] and / or,

[0048] Along the extension direction of the first end surface 5, the microphone 4 in at least one first microphone part 2 is offset from the second end surface 7. There is a distance between the microphone 4 in the first microphone part 2 closest to the second end surface 7 and the second end surface 7. The value of this distance can be determined according to actual conditions and is not limited here.

[0049] In the embodiments provided in this application, refer to Figure 3 As shown, a camera module 9 is provided in the shell 1, and at least one microphone 4 is integrated in the camera module 9. Specifically, the microphones 4 in the first microphone unit 2 are all integrated in the camera module 9. Implementing in this way can make actual manufacturing easier while ensuring good acoustic design and proper sealing of the microphone 4, and having little or no effect on the beamforming algorithm.

[0050] In the embodiment provided in the present application, at least two microphones 4 in the first microphone unit 2 and at least one microphone 4 in the second microphone unit 3 are coplanar to form a first imaginary plane 10 , and the remaining microphones 4 are staggered on the first imaginary plane 10 .

[0051] The microphones 4 in the first microphone part 2 on the first imaginary surface 10 are located on the same straight line, so that the emission points of the beams are on the same straight line, and the microphones 4 of the first microphone part 2 and the microphones 4 of the second microphone part 3 on the first imaginary surface 10 can be on two surfaces respectively, thereby expanding the range of the beam and improving the sound source collection effect.

[0052] In a feasible implementation mode, referring to Figure 2 As shown, the first microphone section 2 has three microphones 4, the second microphone section 3 has two microphones 4, the two microphones 4 in the first microphone section 2 and the one microphone 4 in the second microphone section 3 are coplanar to form a first imaginary plane 10, the extension direction of the first imaginary plane 10 is perpendicular to the second end surface 7, and the remaining multiple microphones 4 are staggered on the first imaginary plane 10 and are all located on the same side of the first imaginary plane 10.

[0053] In the embodiments provided in the present application, at least one microphone 4 is a non-omnidirectional microphone 4. The non-omnidirectional microphone 4 is a microphone 4 pointing in a single direction, and the range of receiving sound signals is a small conical area directly in front of the corresponding pickup hole. Its better directivity enables the microphone 4 to have a good effect on audio collection in a specific direction, and can effectively reduce the income of surrounding environmental noise.

[0054] Based on the microphone array provided in the above embodiment, the present invention also provides a mobile terminal, which is a mobile phone, including the aforementioned microphone array. Since a plurality of microphones 4 are arranged in the shell 1 of the mobile terminal, and the plurality of microphones 4 are distributed on two adjacent end faces, the spacing between at least two adjacent microphones 4 is less than half the wavelength of the response frequency used for beamforming, thereby providing a good microphone 4 layout for the beamforming algorithm, achieving good spatial capture performance with a minimum actual number of microphones 4, and is generally applicable to various modern and traditional beamforming algorithms, so that the mobile terminal can filter out environmental noise and has good sound pickup effect and voice recognition effect.

[0055] The above describes in detail the structure, features and effects of the present invention based on the embodiments shown in the drawings. The above is only a preferred embodiment of the present invention, but the present invention is not limited to the scope of implementation shown in the drawings. Any changes made according to the concept of the present invention, or modifications to equivalent embodiments with equivalent changes, which still do not exceed the spirit covered by the description and drawings, should be within the protection scope of the present invention.

Claims

1. A microphone array, characterized in that: include: A housing having a plurality of microphones built therein, wherein the plurality of microphones form a first microphone unit and a second microphone unit, wherein the first microphone unit has at least two of the microphones, and the second microphone unit has at least one of the microphones; A first end surface formed on one surface of the housing, the first end surface being provided with at least two first sound pickup holes, the first sound pickup holes being connected to the microphones in the first microphone unit in a one-to-one correspondence; A second end surface is formed on the other surface of the housing, the second end surface is provided with at least one second sound pickup hole, and the second sound pickup hole is connected to the microphone in the second microphone part in a one-to-one correspondence; in: The first end surface intersects with the second end surface, an extension direction of the first end surface and an extension direction of the second end surface form a preset angle, and a distance between at least two adjacent microphones is less than half a wavelength of a response frequency for beamforming.

2. The microphone array according to claim 1, characterized in that: Along the extension direction of the first end surface, the distance between at least two adjacent microphones in the first microphone section is less than half the wavelength of the response frequency used for beam forming; and / or, Along the extension direction of the second end surface, a distance between at least two adjacent microphones in the second microphone portion is smaller than a half wavelength of a response frequency for beamforming.

3. The microphone array according to claim 1, characterized in that: Along the extension direction of the second end surface, the microphone in at least one of the second microphone sections is offset from the first end surface; and / or, Along the extension direction of the first end surface, the microphone in at least one of the first microphone sections is offset from the second end surface.

4. The microphone array according to claim 1, characterized in that: A camera module is disposed in the housing, and at least one microphone is integrated in the camera module.

5. The microphone array according to claim 4, characterized in that: The microphones in the first microphone unit are all integrated in the camera module.

6. The microphone array according to claim 1, characterized in that: At least two of the microphones in the first microphone unit and at least one of the microphones in the second microphone unit are coplanar to form a first imaginary plane, and the remaining microphones are staggered on the first imaginary plane.

7. The microphone array according to claim 6, characterized in that: The first microphone unit has three microphones, the second microphone unit has two microphones, the two microphones in the first microphone unit and one microphone in the second microphone unit are coplanar to form the first imaginary plane, and the remaining multiple microphones are staggered on the first imaginary plane and are located on the same side of the first imaginary plane.

8. The microphone array according to claim 1, characterized in that: At least one of the microphones is a non-omnidirectional microphone.

9. The microphone array according to claim 1, characterized in that: The preset angle is 90°.

10. A mobile terminal, characterized in that: Comprising the microphone array according to any one of claims 1-9.

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