A voice assistance system based on phased-array focusing, a phase determination method, and its usage.

Abstract

This application discloses a voice assistance system based on phased array focusing, its manufacturing method, and its usage method, relating to the field of voice-assisted speaking technology. The system includes: a glottal pulse modulator, a phased array drive control system, and an acoustic parametric array; the glottal pulse modulator is used to modulate the original vocal glottal wave signal with a carrier signal that excites an ultrasonic transducer to obtain a modulated signal; the acoustic parametric array includes several ultrasonic transducers; the transmission phase of each ultrasonic transducer is set to the ultrasonic phase emitted by the virtual sound source it receives; the virtual sound source is located at the focusing position; the phased array drive control system is used to control the transmission phase of each ultrasonic transducer when emitting the modulated signal. This application controls the transmission phase of each ultrasonic transducer to the ultrasonic phase emitted by the virtual sound source located at the focusing position, thereby enabling the information emitted by these ultrasonic transducers to be focused at that focusing position.

Description

Technical Field

[0001] This application relates to the field of voice-assisted speaking technology, and in particular to a voice-assisted system based on phased-array focusing, and its manufacturing and usage methods. Background Technology

[0002] Patients with end-stage laryngeal cancer who undergo laryngectomy lose their larynx and vocal cords, resulting in loss of voice. Electro-larynxes are commonly used to provide an external sound source for these patients after laryngectomy. They utilize external sound sources transmitted through neck tissue to the patient's vocal tract and modulated into speech. However, common electro-larynxes using armature motors as the sound source suffer from severe radiated noise problems, unsatisfactory sound production, mechanical speech, and low intelligibility.

[0003] A speech assistance system designed based on acoustic parametric array technology, namely an electronic artificial larynx based on an acoustic parametric array, uses an ultrasonic transducer as the excitation sound source. The ultrasonic waves self-demodulate within human tissue to generate a directional glottic wave signal. This can overcome the problem of radiated noise in traditional electronic artificial larynxes. However, due to the complexity of human tissue, simply using an array-type parametric array system cannot guarantee that the parametric array sound field is focused at a specific location in the human larynx. Summary of the Invention

[0004] The purpose of this application is to provide a voice assistance system based on phased array focusing, and its manufacturing and usage methods, which enables the sound field of the acoustic parametric array to be focused at a specified position in the human throat.

[0005] To achieve the above objectives, this application provides the following solution:

[0006] In a first aspect, this application provides a voice assistance system based on phased array focusing, the voice assistance system based on phased array focusing comprising: a glottal pulse modulator, a phased array drive control system, and an acoustic parametric array;

[0007] A glottal pulse modulator is used to modulate the original vocal glottal wave signal with the carrier signal that excites the ultrasonic transducer to obtain a modulated signal;

[0008] The acoustic parametric array includes a plurality of ultrasonic transducers; the emission phase of each ultrasonic transducer is set to the ultrasonic phase emitted by the virtual sound source it receives; the virtual sound source is located at a focusing position; the focusing position is the focusing position of the ultrasonic transducer;

[0009] A phased array drive control system is used to control the transmission phase of each of the ultrasonic transducers when it transmits the modulated signal.

[0010] Optionally, several of the ultrasonic transducers are arranged in a circular pattern, symmetrical about the sagittal plane of the human body.

[0011] Optionally, the voice assistance system based on phased array focusing further includes: a power supply module;

[0012] The power module is used to supply power to the glottal pulse modulator, the phased array drive control system, and the acoustic parametric array.

[0013] Optionally, the phased-array-based voice assistance system further includes: a power amplifier.

[0014] The power amplifier is used to amplify the power of the modulated signal.

[0015] Optionally, the frequency range of the modulation signal is 20kHz to 200kHz.

[0016] Optionally, each of the ultrasonic transducers has the same center frequency.

[0017] Secondly, this application provides a phase determination method for a phase-controlled focusing-based voice assistance system, the phase determination method for the phase-controlled focusing-based voice assistance system comprising:

[0018] Obtain an image of the neck;

[0019] The focusing position of the ultrasonic transducer is determined based on the neck image;

[0020] The number and placement of the ultrasonic transducers are determined based on the neck image and the focal position.

[0021] The emission phase of each ultrasonic transducer is determined using a time-reversal method based on the placement and focusing position of the ultrasonic transducers; the emission phase of each ultrasonic transducer is the ultrasonic phase emitted by the virtual sound source it receives; the virtual sound source is located at the focusing position.

[0022] Optionally, the focusing position is the mucous membrane on the anterior surface of the trachea.

[0023] Thirdly, this application provides a method for using a phased-array-based voice assistance system, the method comprising:

[0024] Obtain the original glottal wave signal of the phonation;

[0025] The original vocal glottal wave signal is modulated with the carrier signal that excites the ultrasonic transducer to obtain a modulated signal;

[0026] The modulation signal is input into the phased array drive control system to generate ultrasonic waves focused at the focal position; the phased array drive control system controls each ultrasonic transducer to emit the modulation signal and controls the emission phase of each ultrasonic transducer when emitting the modulation signal; the emission phase of each ultrasonic transducer is the ultrasonic phase emitted by the virtual sound source it receives; the virtual sound source is located at the focal position.

[0027] Optionally, the original glottal wave signal is modulated with the carrier signal that excites the ultrasonic transducer to obtain a modulated signal, specifically including:

[0028] The original vocal glottal wave signal and the carrier signal that excites the ultrasonic transducer are orthogonally amplitude modulated to obtain the modulated signal.

[0029] According to the specific embodiments provided in this application, the following technical effects are disclosed:

[0030] This application provides a voice assistance system based on phased array focusing, its manufacturing method, and its usage method. The system includes: a glottal pulse modulator, a phased array drive control system, and an acoustic parametric array. The glottal pulse modulator is used to modulate the original vocal glottal wave signal with a carrier signal that excites an ultrasonic transducer to obtain a modulated signal. The acoustic parametric array includes a plurality of ultrasonic transducers. The transmission phase of each ultrasonic transducer is set to the ultrasonic phase emitted by a virtual sound source it receives. The virtual sound source is located at a focusing position; the focusing position is the focusing position of the ultrasonic transducer. The phased array drive control system is used to control the transmission phase of each ultrasonic transducer when it emits the modulated signal. This application, through the phased array method of controlling the transmission phase of the ultrasonic transducers, enables the sound field of the parametric array to be focused at a specified position in the human throat. This application controls the transmission phase of each ultrasonic transducer to be the ultrasonic phase emitted by a virtual sound source located at the focusing position, thereby enabling the information emitted by these ultrasonic transducers to be focused at that focusing position. This application enables the sound field of the acoustic parametric array to be focused at a specified position in the human throat. Attached Figure Description

[0031] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0032] Figure 1 A schematic diagram of a voice assistance system based on phased array focusing provided in Embodiment 1 of this application;

[0033] Figure 2This is a schematic diagram of the modulation process provided in Embodiment 1 of this application;

[0034] Figure 3 This is a schematic diagram of a preset envelope signal provided in Embodiment 1 of this application;

[0035] Figure 4 This is a schematic diagram of the modulation signal provided in Embodiment 1 of this application;

[0036] Figure 5 This is a schematic diagram of the working process of the phased array drive control system provided in Embodiment 1 of this application;

[0037] Figure 6 This is a schematic diagram of the dual-probe acoustic parametric array provided in Embodiment 1 of this application;

[0038] Figure 7 This is a schematic diagram of the multi-probe acoustic parametric array provided in Embodiment 1 of this application;

[0039] Figure 8 This is a schematic diagram of the power spectrum at the focusing position when dual transducers emit in phase, as provided in Embodiment 1 of this application.

[0040] Figure 9 This is a schematic diagram of the power spectrum at the focusing position during phase-reversed emission of a dual transducer as provided in Embodiment 1 of this application.

[0041] Figure label:

[0042] Power supply module-1, glottal pulse modulator-2, phased array drive control system-3, acoustic parametric array-4. Detailed Implementation

[0043] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0044] Existing speech assistance systems based on acoustic parametric array technology, specifically electronic artificial larynxes based on acoustic parametric arrays, use ultrasonic transducers as the excitation sound source. Ultrasonic waves self-demodulate within human tissue to generate directional glottic wave signals. This overcomes the problem of radiated noise in traditional electronic artificial larynxes.

[0045] However, the conversion efficiency of this technology for electronic artificial laryngeal ultrasound to glottic waves is low, with a conversion efficiency of less than 1% for a long time. Although increasing the original frequency energy of the parametric array can increase the driving signal power of the transducer, the increase in driving signal power is limited due to the safety requirements of human devices, resulting in a bottleneck in conversion efficiency.

[0046] Furthermore, due to the complexity of human tissues, simply using an array-type parametric array system cannot guarantee that the parametric array sound field is focused at a specific location in the human throat. This application introduces phase modulation technology based on phase arrays, which can effectively control the focusing position of each parametric array sound field and ensure that the emitted ultrasound waves are demodulated into glottic waves at the specified location.

[0047] To make the above-mentioned objectives, features and advantages of this application more apparent and understandable, the application will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0048] Example 1:

[0049] In one exemplary embodiment, such as Figure 1 As shown, a voice assistance system based on phased array focusing is provided. The system includes: a glottal pulse modulator 2, a phased array drive control system 3, and an acoustic parametric array 4.

[0050] Glottic pulse modulator 2 is used to modulate the original vocal glottic wave signal with the carrier signal that excites the ultrasonic transducer to obtain a modulated signal, such as... Figure 2 As shown. The glottal pulse modulator 2 uses digital modulation to modulate the amplitude of the carrier signal and the original vocal glottal wave signal. It can be single-sideband or double-sideband modulated in MCU, DSP or FPGA, and the frequency range of the modulated signal is 20kHz to 200kHz.

[0051] In this embodiment, the original glottal wave signal can be derived from the patient's normal speech before the onset of the disease, or from the speech of other normal individuals whose speech is similar to that of the patient. The carrier signal that excites the ultrasound transducer has the same center frequency as the ultrasound transducer to be driven. In this embodiment, the center frequency of the target ultrasound transducer is 50kHz. Double-sideband modulation is used in the MCU to modulate the glottal wave signal and the 50kHz sine wave signal.

[0052] Modulation process and results: The carrier signal that excites the ultrasonic transducer is generated by amplitude modulation (AM). The formula for AM can be expressed as:

[0053] s(t)=(A+m(t))cos(2πf c t);

[0054] Where m(t) is a preset envelope signal, such as Figure 3 As shown; s(t) is the modulation signal, such as Figure 4 As shown; A is the carrier signal amplitude; cos(2πf) c t) represents the carrier signal; f cThis represents the frequency of the carrier signal. The carrier signal is a 50kHz sine wave.

[0055] The acoustic parametric array 4 includes a plurality of ultrasonic transducers; each ultrasonic transducer has the same center frequency, and the emission phase of each ultrasonic transducer is set to the ultrasonic phase emitted by the virtual sound source it receives; the virtual sound source is located at a focusing position; the focusing position is the focusing position of the ultrasonic transducer; the plurality of ultrasonic transducers are arranged in a circle, symmetrical about the sagittal plane of the human body.

[0056] In this context, setting the transmission phase of the ultrasonic transducer can be understood as each transducer's modulated signal having an independent phase delay. The phased array drive control system 3 controls the phase delay of the modulated signal and amplifies its power to achieve phase-independent driving of each ultrasonic transducer unit. This embodiment uses 6 drive channels. The phase delay is implemented in the MCU, and after the delay, the DAC controls the conversion of the modulated digital signal into an analog signal for output, which is then amplified by a power amplifier. The phased array drive control system 3 can adjust the phase difference angle from 0° to 180°.

[0057] This embodiment uses two ultrasonic transducers as excitation sources, with an axial angle of 60° between them. The driving phase delay of the two ultrasonic transducers controls the phase difference of the two carrier signals to be 180°. Simulation calculations are used to determine the power spectrum at the focusing position. When the modulated signals are in phase and the two transducers emit in phase, the power at the focusing position is 87.51 dB, and the power spectrum is as follows. Figure 8 As shown; the phase difference of the modulated signals is 180°, that is, when the dual transducers emit in reverse phase, the power at the focusing position is 13.40dB, and the power spectrum at this time is as follows. Figure 9 As shown, using carrier phase control, the energy of the difference frequency wave can be increased while the energy of the original frequency wave is suppressed. (A comparison is made here: when the phases are the same, the two ultrasonic waves at the focal point suppress each other; when the phase difference is 180°, the two ultrasonic waves are enhanced at the focal point).

[0058] The steps for determining the emission phase of the ultrasonic transducer include:

[0059] 1. Determine the focal point based on the patient's neck CT image. Generally, it is located on the anterior surface mucosa of the trachea. Focusing at this point can cause the mucosa to vibrate and generate glottic waves.

[0060] 2. Design the number and location of ultrasonic transducers. Place 2-N ultrasonic transducers on the horizontal plane passing through the focal point, arranged in a circular pattern. Based on the left-right symmetry of the human body's sagittal plane, cover a 60-180° range in front of the neck (wherein, the "60-180° range in front of the neck" is determined by using a horizontal plane at the neck position as the plane coordinate axis, with the front of the body as the Y-axis, i.e., 90°). The position of the ultrasonic transducers on the human neck can be determined based on CT images. (In this embodiment, two ultrasonic transducers are based on sagittal symmetry, with an included angle of 60°). The more ultrasonic transducers there are, the better, provided there is sufficient space in the front of the human neck; a higher number of transducers results in higher conversion efficiency. When the acoustic parametric array 4 is a dual-probe array... Figure 6 As shown, when the acoustic parametric array 4 is a multi-probe array, as... Figure 7 As shown.

[0061] 3. Determine the emission phase delay of each transducer using a time-reversal algorithm (the phase difference is 180° in this embodiment). Time-reversal algorithm: Place a virtual sound source at the focusing position. The virtual sound source emits ultrasonic signals in all directions. The phase of the ultrasonic waves emitted by the virtual sound source and received by the ultrasonic transducer is the emission phase of the ultrasonic transducer.

[0062] Based on the ultrasonic transducer position and phase delay determined by the above results, a voice assistance system is constructed.

[0063] The phased array drive control system 3 is used to control the transmission phase of each ultrasonic transducer when emitting the modulated signal. The operation of the phased array drive control system is as follows: Figure 5 As shown.

[0064] In addition, the voice assistance system based on phased array focusing also includes: a power supply module 1; the power supply module 1 is used to supply power to the glottal pulse modulator 2, the phased array drive control system 3 and the acoustic parametric array 4.

[0065] The voice assistance system based on phased array focusing further includes: a power amplifier: the power amplifier is used to amplify the power of the modulation signal.

[0066] In this embodiment, the phased-array focused voice assistance system uses a normal speech glottal wave signal modulated with a carrier sinusoidal signal. After filtering and amplitude conditioning, the signal is amplified, and the phase of the excitation signal is controlled to drive the ultrasonic transducer to emit focused ultrasound waves. The ultrasound waves from the transducer self-demodulate into a glottal wave signal within the patient's body, enabling the patient to speak normal speech.

[0067] This embodiment utilizes a focused acoustic parametric array 4 to generate audible sound waves in the human head and neck tissues. It can be equipped with multiple ultrasound transducers, thereby reconstructing the patient's sound source while compensating for the insufficient glottal wave signal energy in the parametric array, and improving the demodulation conversion power of the parametric array sound field within the human body. Therefore, this embodiment can effectively reduce the original frequency sound field energy of the focused parametric array while increasing the glottal wave signal energy.

[0068] Example 2:

[0069] Based on the same inventive concept, this application also provides a phase determination method for a phase-controlled focusing-based voice assistance system as described above. This method is similar to the implementation scheme described in the above embodiments; therefore, the specific limitations in one or more embodiments provided below can be found above. The phase determination method for a phase-controlled focusing-based voice assistance system includes:

[0070] Step S1: Obtain neck image. In this embodiment, the neck image is a CT or MRI image of the neck, or a tomographic image of the neck.

[0071] Step S2: Determine the focusing position of the ultrasound transducer based on the neck image. In this embodiment, the focusing position is the mucosa on the anterior surface of the trachea.

[0072] Step S3: Determine the number and placement of the ultrasonic transducers based on the neck image and the focusing position.

[0073] Step S4: Determine the emission phase of each ultrasonic transducer using a time-reversal method based on the placement and focusing position of the ultrasonic transducer; the emission phase of each ultrasonic transducer is the ultrasonic phase emitted by the virtual sound source it receives; the virtual sound source is located at the focusing position.

[0074] Example 3:

[0075] Based on the same inventive concept, this application also provides a method for using the aforementioned phased-array-based voice assistance system, the method of using the phased-array-based voice assistance system including:

[0076] Step A1: Obtain the original vocal glottal wave signal.

[0077] Step A2: Perform orthogonal amplitude modulation on the original vocal glottal wave signal and the carrier signal that excites the ultrasonic transducer to obtain the modulated signal.

[0078] Step A3: Input the modulation signal into the phased array drive control system 3 to generate ultrasonic waves focused at the focal position; the phased array drive control system 3 controls each ultrasonic transducer to emit the modulation signal and controls the emission phase of each ultrasonic transducer when emitting the modulation signal; the emission phase of each ultrasonic transducer is the ultrasonic phase emitted by the virtual sound source it receives; the virtual sound source is located at the focal position.

[0079] It should be noted that the user information (including but not limited to user device information, user personal information, etc.) and data (including but not limited to data used for analysis, data stored, data displayed, etc.) involved in this application are all information and data authorized by the user or fully authorized by all parties, and the collection, use and processing of the relevant data must comply with relevant regulations.

[0080] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0081] This document uses specific examples to illustrate the principles and implementation methods of this application. The descriptions of the above embodiments are only for the purpose of helping to understand the methods and core ideas of this application. Furthermore, those skilled in the art will recognize that, based on the ideas of this application, there will be changes in the specific implementation methods and application scope. Therefore, the content of this specification should not be construed as a limitation of this application.

Claims

1. A phase focused based voice assistant system, characterized in that, The phase focusing-based voice auxiliary system comprises a glottal wave pulse modulator, a phased array driving control system and an acoustic parametric array. The glottal wave pulse modulator is used for modulating an original pronunciation glottal wave signal and a carrier signal exciting an ultrasonic transducer to obtain a modulated signal. The acoustic parametric array comprises a plurality of ultrasonic transducers; the emission phase of each ultrasonic transducer is set as the ultrasonic phase emitted by a virtual sound source received by the ultrasonic transducer; the virtual sound source is located at a focusing position; the focusing position is the focusing position of the ultrasonic transducer; and the focusing position is the mucosa of the anterior surface of the trachea. The emission phase determination method of the ultrasonic transducer comprises: acquiring a neck image; determining the focusing position of the ultrasonic transducer according to the neck image; According to the neck image and the focus position, the number and the placement position of the ultrasonic transducers are determined; and the ultrasonic transducers are arranged on a plane passing through the focus point According to the neck image and the focus position, the number and the placement position of the ultrasonic transducers are determined; and the ultrasonic transducers are arranged on a plane passing through the focus point The range of the front part of the neck of the human body is covered. determining the emission phase of each ultrasonic transducer by using a time reversal method according to the placement position and the focusing position of the ultrasonic transducer; the time reversal method is that a virtual sound source is placed at the focusing position, the virtual sound source emits ultrasonic signals to the surrounding, and the ultrasonic phase emitted by the virtual sound source received by the ultrasonic transducer is the emission phase of the ultrasonic transducer; The phased array driving control system is used for controlling the emission phase of each ultrasonic transducer when emitting the modulated signal.

2. The phase focused based voice assist system of claim 1, wherein, The phase focusing-based voice auxiliary system further comprises a power module; The power module is used for supplying power to the glottal wave pulse modulator, the phased array driving control system and the acoustic parametric array.

3. The phase focused based voice aid system of claim 1, wherein, The phase focusing-based voice auxiliary system further comprises a power amplifier: The power amplifier is used for power amplifying the modulated signal.

4. The phase focused based voice aid system of claim 1, wherein, The frequency range of the modulated signal is 20 kHz-200 kHz.

5. The phase focused based voice aid system of claim 1, wherein, The center frequencies of each ultrasonic transducer are the same.

6. A phase determination method for a phase-controlled focusing based voice assistant system, characterized in that, The phase determination method of the phase focusing-based voice auxiliary system comprises: acquiring a neck image; determining the focusing position of the ultrasonic transducer according to the neck image; the focusing position is the mucosa of the anterior surface of the trachea; According to the neck image and the focus position, the number and the placement position of the ultrasonic transducers are determined; and the ultrasonic transducers are arranged on a plane passing through the focus point According to the neck image and the focus position, the number and the placement position of the ultrasonic transducers are determined; and the ultrasonic transducers are arranged on a plane passing through the focus point The range of the front part of the neck of the human body is covered. determining the emission phase of each ultrasonic transducer by using a time reversal method according to the placement position and the focusing position of the ultrasonic transducer; the emission phase of each ultrasonic transducer is the ultrasonic phase emitted by a virtual sound source received by the ultrasonic transducer; the virtual sound source is located at the focusing position; the time reversal method is that a virtual sound source is placed at the focusing position, the virtual sound source emits ultrasonic signals to the surrounding, and the ultrasonic phase emitted by the virtual sound source received by the ultrasonic transducer is the emission phase of the ultrasonic transducer.

7. A method of using a phase focused based voice assistant system as claimed in claim 1, wherein, comprises: acquiring an original pronunciation glottal wave signal; modulating the original pronunciation glottal wave signal and a carrier signal exciting an ultrasonic transducer to obtain a modulated signal; inputting the modulated signal into a phased array driving control system to generate ultrasonic waves focused at a focusing position; the phased array driving control system controls each ultrasonic transducer to emit the modulated signal and controls the emission phase of each ultrasonic transducer when emitting the modulated signal; the emission phase of each ultrasonic transducer is the ultrasonic phase emitted by a virtual sound source received by the ultrasonic transducer; the virtual sound source is located at the focusing position.

8. The method of using a phase-focused based voice assist system of claim 7, wherein, modulating the original pronunciation glottal wave signal and a carrier signal exciting an ultrasonic transducer to obtain a modulated signal, specifically comprising: The original sound glottal wave signal is quadrature amplitude modulated with a carrier signal exciting an ultrasonic transducer to obtain a modulated signal. The original sound glottal wave signal is quadrature amplitude modulated with a carrier signal exciting an ultrasonic transducer to obtain a modulated signal.

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