Acoustic transducer module and directivity control method thereof
By designing the hardware of the module's rear cavity and phase adjustment circuit, and combining it with the acoustic waveguide, the phase of the electrical signal can be adjusted independently, solving the problem of high cost of acoustic transducers and achieving low-cost directional control.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- AAC TECHNOLOGIES (NANJING) CO LTD
- Filing Date
- 2025-12-23
- Publication Date
- 2026-04-28
AI Technical Summary
The acoustic radiation directivity control of existing acoustic transducers relies on high-performance chips, resulting in high costs.
The hardware structure design employs a module rear cavity, a phase adjustment circuit, and multiple sound generating units. The phase of the electrical signal is independently adjusted through the phase adjustment circuit, and combined with the acoustic waveguide design of the module front cavity, the control of the sound phase is achieved, avoiding dependence on high-performance chips.
It achieves directional control of acoustic transducers, reduces costs, and does not require complex algorithm support.
Smart Images
Figure CN121938337A_ABST
Abstract
Description
Technical Field
[0001] This disclosure relates to the field of acoustic equipment technology, and in particular to an acoustic transducer module and a method for controlling the directivity of the acoustic transducer module. Background Technology
[0002] Acoustic transducers play a vital role in various fields. In related technologies, the control of the acoustic radiation directivity of acoustic transducers is achieved through algorithmic adjustments. That is, the audio signal from each output channel is processed by an algorithm so that after the audio output signal is played through a speaker, the sound field is superimposed in space to form a certain directivity. Due to the high complexity of the algorithm, this method requires high-performance chips, resulting in high costs for acoustic transducers. Summary of the Invention
[0003] To overcome the problems existing in related technologies, this disclosure provides an acoustic transducer module and a method for controlling the directivity of the acoustic transducer module.
[0004] According to a first aspect of the present disclosure, an acoustic transducer module is provided, including: a module rear cavity, a phase adjustment circuit, a plurality of sound generating units, and a module front cavity; The rear cavity of the module is used to accommodate the plurality of sound-generating units and the phase adjustment circuit; The phase adjustment circuit includes at least one signal input terminal and multiple phase adjustment branches. The signal input terminal is used to receive an input electrical signal, and the multiple phase adjustment branches are used to adjust the phase of the electrical signal. Each phase adjustment branch is connected to at least one of the multiple sound generating units. The plurality of sound-generating units are used to convert the received electrical signals into sound signals; The module front cavity includes a radiation port for converging and radiating the acoustic signal outwards.
[0005] In some embodiments, each phase adjustment branch includes: at least one RC circuit, and each RC circuit includes: a capacitor and a resistor; Wherein, the first end of the resistor is the electrical signal input end, and the second end of the resistor is the electrical signal output end; The first terminal of the capacitor is connected to the second terminal of the resistor, and the second terminal of the capacitor is grounded. The input-output relationship of each phase adjustment branch is as follows: ; in, For resistance; For capacitors; For complex frequencies, For the real part, The virtual part, Angular frequency, This represents the number of RC circuits.
[0006] In some embodiments, there are multiple RC circuits, which are cascaded together, with the electrical signal output terminal of the previous RC circuit connected to the electrical signal input terminal of the next RC circuit.
[0007] In some embodiments, the number of signal input terminals is multiple, and each signal input terminal is connected to a different phase adjustment branch; Each signal input terminal is used to receive electrical signals of different phases and transmit the received electrical signals to the respective phase adjustment branches connected to it.
[0008] In some embodiments, the module front cavity further includes: a plurality of acoustic waveguides; Each acoustic waveguide is used to receive acoustic signals emitted by at least one sound-generating unit, and at least some of the acoustic waveguides have different lengths. The radiating port is used to converge and radiate the acoustic signals transmitted by the multiple acoustic waveguides.
[0009] In some embodiments, the module front cavity includes: an inlet grid, a resonant cavity, and an outlet cover plate, wherein the inlet grid, the resonant cavity, and the outlet cover plate together form the plurality of acoustic waveguides; The inlet grid is located on the side of the resonant cavity near the sound-generating unit, and is used to control the projected area of the sound-generating unit on the resonant cavity, and to close at least part of the side of the resonant cavity near the sound-generating unit; The outlet cover is located on the side of the resonant cavity away from the sound-generating unit, and is used to close the side of the resonant cavity away from the sound-generating unit. The outlet cover is provided with the radiation port.
[0010] In some embodiments, the area of the resonant cavity not enclosed by the inlet grid is greater than or equal to half the diaphragm area of the plurality of sound-generating units.
[0011] In some embodiments, the module rear cavity includes: a front cover plate and a rear cover plate; The front cover and the rear cover are arranged opposite to each other, together forming a cavity for accommodating the plurality of sound-generating units and the phase adjustment circuit.
[0012] In some embodiments, the front cover includes a limiting hole for limiting the displacement of the sound-generating unit.
[0013] In some embodiments, the arrangement of the plurality of sound-generating units includes one of the following: linear array arrangement, surface array arrangement, and spherical array arrangement.
[0014] According to a second aspect of this disclosure, a method for controlling the directivity of an acoustic transducer module is provided, applied to the acoustic transducer module as described in the first aspect, the method comprising: Acquire the input signal of the acoustic transducer module; The phase of the input signal is adjusted independently by each phase adjustment branch in the phase adjustment circuit, and the adjusted input signal is transmitted to different sound generating units to generate multiple point sound sources. The sound sources from each point are converged to the radiation port of the module's front cavity, so that the sound sources are positively superimposed in the target propagation direction and negatively canceled in the non-target propagation direction, and directional sound signals are radiated outward through the radiation port: Where the front cavity of the module does not include an acoustic waveguide, the directional acoustic signal is: ; When the module front cavity includes multiple acoustic waveguides, the multiple point sound sources converge to the radiation port after undergoing phase adjustment again through the acoustic waveguides, and the directional acoustic signal is: ; In the above formulas, It is a directional acoustic signal; For the input signal, the first The original phase of each frequency component; Representing different frequency components; Indicates time; This indicates that the phase adjustment circuit affects the first... Each sound source is in Phase adjustment at angular frequency; That is, the first Each sound source is in The magnitude of the phase that converges to the radiation port after being adjusted by the phase adjustment circuit at the angular frequency; Indicates the acoustic waveguide to the first Each sound source is in Phase adjustment at angular frequency; express The wave number corresponding to the angular frequency; Indicates the first The distance of the propagation path of sound waves emitted from a point sound source within the corresponding acoustic waveguide; That is, the first Each sound source is in The phase magnitude of the light that converges to the radiation port after being adjusted sequentially by the phase adjustment circuit and the acoustic waveguide at the angular frequency; represents an imaginary number; This represents the amplitude component of each frequency element; Indicates the total number of frequency components; Indicates the first One frequency component; It is a natural constant; Indicates the first Electroacoustic transduction transfer function of a point sound source; Indicates the total number of point sound sources; This represents the convolution operation.
[0015] The acoustic transducer module provided in this disclosure includes: a rear cavity, a phase adjustment circuit, multiple sound-emitting units, and a front cavity. The rear cavity houses the multiple sound-emitting units and the phase adjustment circuit. The phase adjustment circuit includes at least one signal input terminal and multiple phase adjustment branches. The signal input terminal receives an input electrical signal, and the multiple phase adjustment branches adjust the phase of the electrical signal. Each phase adjustment branch is connected to at least one of the multiple sound-emitting units. The multiple sound-emitting units convert the received electrical signal into an acoustic signal. The front cavity includes a radiation port for converging and radiating the acoustic signal. This disclosure allows for the control of sound radiation directivity through a hardware structure using a phase adjustment circuit, eliminating the need for complex algorithms or high-performance chips and saving costs.
[0016] It should be understood that the above general description and the following detailed description are exemplary and explanatory only, and are not intended to limit this disclosure. Attached Figure Description
[0017] Figure 1 A schematic diagram of the structure of an acoustic transducer module according to an embodiment of this disclosure is shown.
[0018] Figure 2 A schematic diagram of a phase adjustment circuit according to an embodiment of the present disclosure is shown.
[0019] Figure 3 A schematic diagram of a phase adjustment branch in an embodiment of this disclosure is shown.
[0020] Figure 4 A schematic diagram of the front cavity of a module is shown in an embodiment of this disclosure.
[0021] Figure label: 100 - Module rear cavity; 110 - Front cover plate; 120 - Rear cover plate; 200 - Phase adjustment circuit; 210 - Signal input terminal; 220 - Phase adjustment branch; 221 - Capacitor; 222 - Resistor; 300 - Sound unit; 400 - Module front cavity; 410 - Radiation port; 420 - Inlet grid; 430 - Resonance cavity; 440 - Outlet cover plate. Detailed Implementation
[0022] Exemplary embodiments will now be described in detail, examples of which are illustrated in the accompanying drawings. When the following description relates to the drawings, unless otherwise indicated, the same numerals in different drawings denote the same or similar elements. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with this disclosure. Rather, they are merely examples of apparatuses and methods consistent with some aspects of this disclosure as detailed in the appended claims.
[0023] First, please refer to... Figure 1 , Figure 1 This diagram illustrates the structure of an acoustic transducer module according to an embodiment of the present disclosure, as shown below. Figure 1 As shown, the acoustic transducer module includes: a rear cavity 100, a phase adjustment circuit 200, multiple sound generating units 300, and a front cavity 400.
[0024] The module's rear cavity 100 is used to accommodate multiple sound-generating units 300 and a phase adjustment circuit 200.
[0025] The phase adjustment circuit 200 includes at least one signal input terminal 210 and multiple phase adjustment branches 220. The signal input terminal 210 is used to receive an input electrical signal, and the multiple phase adjustment branches 220 are used to adjust the phase of the electrical signal respectively. Each phase adjustment branch 220 is connected to at least one of the multiple sound generating units 300.
[0026] The signal input terminal 210 can transmit the received electrical signal to the phase adjustment branch 220 connected to it. Each phase adjustment branch 220 can, based on its circuit structure, change the phase of the electrical signal at the hardware level and transmit the phase-changed electrical signal to the sound unit 300 connected to it. The adjustment range of the sound phase by each phase adjustment branch 220 can be the same or different.
[0027] The sound-generating unit 300 can convert the received electrical signal into a sound signal.
[0028] The module front cavity 400 includes a radiation port 410, which is used to gather and radiate acoustic signals to the outside.
[0029] It is understandable that controlling the directivity of sound radiation is essentially controlling the phase of the sound. This disclosure achieves independent control of the phase of the sound signals output by each sound-generating unit 300 in the acoustic transducer module by adding a phase adjustment circuit 200 on the hardware. Sound signals of different phases can form a directional sound output after converging at the radiation port 410.
[0030] Please continue to refer to Figure 1In some embodiments, the module rear cavity 100 includes a front cover plate 110 and a rear cover plate 120. The front cover plate 110 and the rear cover plate 120 are disposed opposite to each other and together form a cavity for accommodating a plurality of sound generating units 300 and a phase adjustment circuit 200.
[0031] For example, the front cover 110 includes limiting holes arranged in an array to limit the displacement of the sound-emitting unit 300. The sound-emitting unit 300 can be installed in the limiting holes of the front cover 110, thereby forming various array arrangements. For example, linear array arrangement, surface array arrangement, and spherical array arrangement. Figure 1 The sound-generating unit 300 is arranged in a surface array.
[0032] The front cover 110 and the rear cover 120 form a nearly enclosed cavity, which is shared by all the sound-generating units 300. Meanwhile, the phase adjustment circuit 200 is located inside this cavity on the side near the rear cover 120.
[0033] Please refer to the following. Figure 2 , Figure 2 A schematic diagram of the phase adjustment circuit 200 in an embodiment of this disclosure is shown.
[0034] like Figure 2 As shown, the phase adjustment circuit 200 can be a printed circuit board composed of multiple passive electronic devices, and multiple phase adjustment branches 220 can form multiple independent phase adjustment analog filters.
[0035] Each phase adjustment branch 220 includes at least one RC circuit, and each RC circuit includes a capacitor 221 and a resistor 222. The first terminal of resistor 222 is the electrical signal input terminal, and the second terminal of resistor 222 is the electrical signal output terminal. The first terminal of capacitor 221 is connected to the second terminal of resistor, and the second terminal of capacitor 221 is grounded.
[0036] Specifically, please refer to Figure 3 , Figure 3 A schematic diagram of the structure of a phase adjustment branch 220 in an embodiment of this disclosure is shown.
[0037] like Figure 3 As shown, the phase adjustment branch 220 can be a first-order all-pass phase adjustment circuit 200 including an RC circuit, whose input... With output The relationship between them is: ; in, For resistance; For capacitors; For complex frequencies, For the real part, The virtual part, ω is the angular frequency.
[0038] For example, there can be multiple RC circuits, which are cascaded together, with the electrical signal output terminal of the previous RC circuit connected to the electrical signal input terminal of the next RC circuit.
[0039] Specifically, the two RC circuits are connected in series to form a second-order all-pass phase adjustment branch 220, whose input... With output The relationship between them is: ; in, For resistance; For capacitors; For complex frequencies, For the real part, The virtual part, ω is the angular frequency.
[0040] Similarly, the general formula for the input-output relationship of each phase adjustment branch 220 can be expressed as: ; in, For resistance; For capacitors; For complex frequencies, For the real part, The virtual part, Angular frequency, This represents the number of RC circuits.
[0041] By designing phase adjustment branches 220 with different resistance and capacitance values, different phase adjustment amplitudes can be achieved. Furthermore, by using higher-order phase adjustment branches 220, the phase adjustment amplitude can be made more accurate.
[0042] In some embodiments, the phase adjustment circuit 200 may have multiple signal input terminals 210, each of which is connected to a different phase adjustment branch 220. Each signal input terminal 210 is used to receive electrical signals of different phases and transmit the received electrical signals to the respective phase adjustment branch 220 connected to it.
[0043] By designing a multi-channel input phase adjustment circuit 200, different input phases can be combined with the phase adjustment branch 220 to adjust the phase of the output electrical signal, thereby improving the versatility of the phase adjustment branch 220 to a certain extent. For example, assuming that the phase adjustment amplitude of the phase adjustment branch 220 is 180°, if it is desired to delay the phase of the electrical signal output by a certain phase adjustment branch 220 by 270°, the input terminal of the phase adjustment branch 220 can be connected to the signal input terminal 210 for receiving the electrical signal that has already been delayed by 90°. In this case, it is only necessary to delay the input electrical signal that has already been delayed by 90° by another 180° using the phase adjustment branch 220, without adjusting the structure of the phase adjustment branch 220.
[0044] Please refer to Figure 4 In some embodiments, the module front cavity 400 further includes a plurality of acoustic waveguides. Each acoustic waveguide is used to receive acoustic signals emitted by at least one sound-emitting unit 300, and at least some of the acoustic waveguides have different lengths. The radiation port 410 is used to converge and radiate the acoustic signals transmitted by the plurality of acoustic waveguides.
[0045] It is understandable that point sound sources at different locations on the sound-generating unit 300 can radiate sound outwards through different sound waveguides in the module's front cavity 400. Due to the different propagation paths, the phase of the sound waves actually radiated outwards at the radiation port 410 by each point sound source will also be different. By designing the structural path of the propagation path of point sources at different locations within the front cavity, passive phase control of the radiated sound waves from point sources at different locations can be achieved.
[0046] In this disclosure, the phase adjustment circuit 200 can be used to adjust the phase of the electrical signal, while the acoustic waveguide can be used to adjust the phase of the acoustic signal output by the sound generating unit 300. The combination of the two determines the directivity of the sound ultimately radiated by the radiation port 410.
[0047] Specifically, the electrical signal input to the phase adjustment circuit 200 is adjusted by different phase adjustment branches 220 to form a new signal with the same amplitude but different phase as the original input signal. The adjusted electrical signal is then fed to different point source sound generating units 300 on the point source array. The sound generating unit 300 converts the electrical signal into a sound signal and inputs it into the sound waveguide, thereby achieving a secondary adjustment of the sound phase. The results of the two phase adjustments are superimposed to obtain the final phase adjustment result.
[0048] Please continue to refer to Figure 4The module front cavity 400 includes an inlet grid 420, a resonant cavity 430, and an outlet cover plate 440. The inlet grid 420, resonant cavity 430, and outlet cover plate 440 together form multiple acoustic waveguides. The inlet grid 420 is located on the side of the resonant cavity 430 closest to the sound-generating unit 300, used to control the projected area of the sound-generating unit 300 on the resonant cavity 430, and to close at least a portion of the resonant cavity 430 on the side closest to the sound-generating unit 300. The outlet cover plate 440 is located on the side of the resonant cavity 430 furthest from the sound-generating unit 300, used to close the side of the resonant cavity 430 furthest from the sound-generating unit 300, and the outlet cover plate 440 has a radiation port 410.
[0049] Understandably, the shape of the resonant cavity 430 determines the maximum length of the acoustic waveguide, while the inlet grid 420 is used to close the side of the resonant cavity 430 near the sound-generating unit 300 and to connect the sound-generating unit 300 to the acoustic waveguide. The outlet cover 440 is used to close the side of the resonant cavity 430 away from the sound-generating unit 300 and provides a radiation port 410 for converging and radiating directional acoustic signals. The closed resonant cavity 430 forms an acoustic waveguide capable of controlling the sound propagation path.
[0050] In some embodiments, the area of the resonant cavity 430 not enclosed by the inlet grid 420 is greater than or equal to half the diaphragm area of the plurality of sound-generating units 300. This portion of the resonant cavity 430 not enclosed by the inlet grid 420 can be understood as the part of the acoustic waveguide that can directly receive the acoustic signal emitted by the sound-generating units 300. If this portion is too small, the acoustic signal initially received by the acoustic waveguide will suffer significant loss, resulting in a low loudness of the sound ultimately output through the radiation port 410. Therefore, it is necessary to limit the relationship between the area of the resonant cavity 430 not enclosed by the inlet grid 420 and the diaphragm area of the plurality of sound-generating units 300 to ensure that the output sound has sufficient loudness.
[0051] The phase relationship between the input and output signals of the acoustic transducer module provided in this disclosure will be explained in detail through formula derivation.
[0052] Set the input signal of the mono channel of the input phase adjustment circuit to And expressed as the superposition of multiple simple harmonic waves as follows: ; in, This represents the amplitude component of each frequency element; Representing different frequency components; represents an imaginary number; Indicates time; Indicates the total number of frequency components; Indicates the first One frequency component; It is a natural constant.
[0053] The input signal first passes through a phase adjustment circuit, where multiple phase adjustment branches adjust the input phase for different point sound sources. The signal after adjusting the individual sound sources is Its expression is as follows: ; in, Indicates the first Each sound source is in The magnitude of phase adjustment at angular frequency.
[0054] The signal, after being adjusted by the phase adjustment circuit, is fed to different sound-generating units 300 for electroacoustic conversion and sound generation. Each point sound source receives a guided signal and converts it into an acoustic signal. Its expression is as follows: ; in, Indicates the first Electroacoustic transduction transfer function of a point sound source; This represents the convolution operation.
[0055] When the module's front cavity includes multiple acoustic waveguides, the phase characteristics of sounds emitted from different sound sources change as they propagate through different acoustic waveguides. Sound signals emitted by a point sound source After propagation through the corresponding acoustic waveguide, the actual sound signal radiated outward at the radiation port 410 is: Its expression is as follows: ; in, Indicates the first The distance of the propagation path of sound waves emitted from a point sound source within the corresponding acoustic waveguide; express The wave number corresponding to the angular frequency is calculated using the following formula: ; in, Indicates angular frequency; It indicates the speed of sound.
[0056] Ultimately, the total sound wave superimposed at the radiation port 410 from all point sound sources constitutes the sound wave radiated outward by the entire acoustic transducer module. Its expression is as follows: ; in, This indicates the total number of point sound sources.
[0057] Compare input signals and output sound waves It can be observed that, through passive adjustment of the acoustic transducer module provided in this disclosure, the original in-phase radiation of each point sound source in different frequency bands can be changed into radiation of different phases. When the phases between the point sound sources are completely in phase, the sound waves radiated by each point sound source are completely positively superimposed; when the phases between the point sound sources are completely opposite, the sound waves radiated by each point sound source are completely negatively canceled; when the phases between the point sound sources are between completely in phase and completely opposite, the sound waves will be vectorly superimposed at different angles and directions, thus producing different radiation directivity results. Through the above design control, the radiation directivity control of the entire acoustic transducer module can be achieved.
[0058] Based on the same inventive concept, this disclosure also provides a method for controlling the directivity of an acoustic transducer module, applicable to, for example... Figures 1 to 4 The acoustic transducer module shown includes a method comprising: Acquire the input signal of the acoustic transducer module.
[0059] The phase of the input signal is adjusted independently by each phase adjustment branch in the phase adjustment circuit, and the adjusted input signal is transmitted to different sound generating units to generate multiple point sound sources.
[0060] The sound sources at each point are converged to the radiation port of the module's front cavity, so that the sound sources at each point are positively superimposed in the target propagation direction and negatively canceled in the non-target propagation direction, and directional sound signals are radiated outward through the radiation port.
[0061] In the case where the front cavity of the module does not include the acoustic waveguide, the directional acoustic signal is: ; When the module's front cavity includes multiple acoustic waveguides, the multiple point sound sources converge to the radiation port after undergoing phase adjustment again through the acoustic waveguides. The directional acoustic signal is: ; In the above formulas, It is a directional acoustic signal; For the input signal, the first The original phase of each frequency component; Representing different frequency components; Indicates time; This indicates that the phase adjustment circuit affects the first... Each sound source is in Phase adjustment at angular frequency; That is, the first Each sound source is in The magnitude of the phase that converges to the radiation port after being adjusted by the phase adjustment circuit at the angular frequency; Indicates the acoustic waveguide to the first Each sound source is in Phase adjustment at angular frequency; express The wave number corresponding to the angular frequency; Indicates the first The distance of the propagation path of sound waves emitted from a point sound source within the corresponding acoustic waveguide; That is, the first Each sound source is in The phase magnitude of the light that converges to the radiation port after being adjusted sequentially by the phase adjustment circuit and the acoustic waveguide at the angular frequency; represents an imaginary number; This represents the amplitude component of each frequency element; Indicates the total number of frequency components; Indicates the first One frequency component; It is a natural constant; Indicates the first Electroacoustic transduction transfer function of a point sound source; Indicates the total number of point sound sources; This represents the convolution operation.
[0062] The embodiments disclosed herein can control the phase of the sound focused at the radiation port by means of a phase adjustment circuit, or by combining a phase adjustment circuit with an acoustic waveguide, thereby achieving directional control of the acoustic signal output by the acoustic transducer module.
[0063] The embodiments of this disclosure have been described in detail above with reference to the accompanying drawings. However, this disclosure is not limited to the specific details of the above embodiments. Within the scope of the technical concept of this disclosure, various simple modifications can be made to the technical solutions of this disclosure, and these simple modifications all fall within the protection scope of this disclosure.
[0064] Furthermore, various different embodiments of this disclosure can be combined in any way, as long as they do not violate the spirit of this disclosure, they should also be regarded as the content disclosed in this disclosure.
Claims
1. An acoustic transducer module, characterized in that, include: The module includes a rear cavity, a phase adjustment circuit, multiple sound units, and a front cavity. The rear cavity of the module is used to accommodate the plurality of sound-generating units and the phase adjustment circuit; The phase adjustment circuit includes: at least one signal input terminal and multiple phase adjustment branches. The signal input terminal is used to receive an input electrical signal, and the multiple phase adjustment branches are used to adjust the phase of the electrical signal. Each phase adjustment branch is connected to at least one of the multiple sound generating units. The plurality of sound-generating units are used to convert the received electrical signals into sound signals; The module front cavity includes a radiation port for converging and radiating the acoustic signal outwards.
2. The acoustic transducer module according to claim 1, characterized in that, Each phase adjustment branch includes: at least one RC circuit, and each RC circuit includes: a capacitor and a resistor; Wherein, the first end of the resistor is the electrical signal input end, and the second end of the resistor is the electrical signal output end; The first terminal of the capacitor is connected to the second terminal of the resistor, and the second terminal of the capacitor is grounded. The input-output relationship of each phase adjustment branch is as follows: ； in, For resistance; For capacitors; For complex frequencies, For the real part, The virtual part, Angular frequency, This represents the number of RC circuits.
3. The acoustic transducer module according to claim 2, characterized in that, The number of RC circuits is multiple, and the multiple RC circuits are cascaded with each other. The electrical signal output terminal of the previous stage RC circuit is connected to the electrical signal input terminal of the next stage RC circuit.
4. The acoustic transducer module according to any one of claims 1 to 3, characterized in that, The number of signal input terminals is multiple, and each signal input terminal is connected to a different phase adjustment branch; Each signal input terminal is used to receive electrical signals of different phases and transmit the received electrical signals to the respective phase adjustment branches connected to it.
5. The acoustic transducer module according to claim 1, characterized in that, The module front cavity also includes: multiple acoustic waveguides; Each acoustic waveguide is used to receive acoustic signals emitted by at least one sound-generating unit, and at least some of the acoustic waveguides have different lengths. The radiating port is used to converge and radiate the acoustic signals transmitted by the multiple acoustic waveguides.
6. The acoustic transducer module according to claim 5, characterized in that, The module front cavity includes an inlet grid, a resonant cavity, and an outlet cover plate, wherein the inlet grid, the resonant cavity, and the outlet cover plate together form the plurality of acoustic waveguides; The inlet grid is located on the side of the resonant cavity near the sound-generating unit, and is used to control the projected area of the sound-generating unit on the resonant cavity, and to close at least part of the side of the resonant cavity near the sound-generating unit; The outlet cover is located on the side of the resonant cavity away from the sound-generating unit, and is used to close the side of the resonant cavity away from the sound-generating unit. The outlet cover is provided with the radiation port.
7. The acoustic transducer module according to claim 6, characterized in that, The area of the resonant cavity that is not enclosed by the inlet grid is greater than or equal to half the diaphragm area of the plurality of sound-generating units.
8. The acoustic transducer module according to claim 1, characterized in that, The module's rear cavity includes: a front cover plate and a rear cover plate; The front cover and the rear cover are arranged opposite to each other, together forming a cavity for accommodating the plurality of sound-generating units and the phase adjustment circuit.
9. The acoustic transducer module according to claim 8, characterized in that, The front cover includes a limiting hole for limiting the displacement of the sound-generating unit.
10. The acoustic transducer module according to claim 1, characterized in that, The arrangement of the multiple sound-generating units includes one of the following: linear array arrangement, surface array arrangement, and spherical array arrangement.
11. A method for controlling the directivity of an acoustic transducer module, characterized in that, Applied to an acoustic transducer module as described in any one of claims 1 to 10, the method comprises: Acquire the input signal of the acoustic transducer module; The phase of the input signal is adjusted independently by each phase adjustment branch in the phase adjustment circuit, and the adjusted input signal is transmitted to different sound generating units to generate multiple point sound sources. The sound sources from each point are converged to the radiation port of the module's front cavity, so that the sound sources are positively superimposed in the target propagation direction and negatively canceled in the non-target propagation direction, and directional sound signals are radiated outward through the radiation port: Where the front cavity of the module does not include an acoustic waveguide, the directional acoustic signal is: ； When the module front cavity includes multiple acoustic waveguides, the multiple point sound sources converge to the radiation port after undergoing phase adjustment again through the acoustic waveguides, and the directional acoustic signal is: ； In the above formulas, It is a directional acoustic signal; For the input signal, the first The original phase of each frequency component; Representing different frequency components; Indicates time; This indicates that the phase adjustment circuit affects the first... Each sound source is in Phase adjustment at angular frequency; That is, the first Each sound source is in The magnitude of the phase that converges to the radiation port after being adjusted by the phase adjustment circuit at the angular frequency; Indicates the acoustic waveguide to the first Each sound source is in Phase adjustment at angular frequency; express The wave number corresponding to the angular frequency; Indicates the first The distance of the propagation path of sound waves emitted from a point sound source within the corresponding acoustic waveguide; That is, the first Each sound source is in The phase magnitude of the light that converges to the radiation port after being adjusted sequentially by the phase adjustment circuit and the acoustic waveguide at the angular frequency; represents an imaginary number; This represents the amplitude component of each frequency element; Indicates the total number of frequency components; Indicates the first One frequency component; It is a natural constant; Indicates the first Electroacoustic transduction transfer function of a point sound source; Indicates the total number of point sound sources; This represents the convolution operation.