Voice-assisted system based on phase-controlled focusing, phase determination method and use method

Abstract

The invention discloses a voice auxiliary system based on phase control focusing and a manufacturing method and a using method thereof, and relates to the technical field of voice auxiliary speaking, and the 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 the original pronunciation glottal wave signal and the carrier signal of the excitation ultrasonic transducer to obtain a modulation signal; the acoustic parametric array comprises a plurality of ultrasonic transducers; the emission phase of each ultrasonic transducer is set to be the ultrasonic phase emitted by the received virtual sound source; the virtual sound source is located at a focusing position; and the phased array driving control system is used for controlling the transmitting phase when each ultrasonic transducer transmits the modulation signal. According to the invention, the emission phase of each ultrasonic transducer is controlled to be the ultrasonic phase emitted by the virtual sound source located at the focusing position, so that the information emitted by the ultrasonic transducers can be focused at the focusing position.

Description

Technical Field

[0001] The present application relates to the field of voice assistant technology, and in particular to a voice assistant system based on phased-control focusing and a manufacturing method and a use method thereof. Background Art

[0002] After laryngectomy, patients with terminal laryngeal cancer lose their larynx and vocal cords, and lose their ability to speak. Electronic artificial larynx is often used to provide an external sound source for laryngeal cancer patients after laryngectomy. It uses the external sound source to enter the patient's vocal tract through the neck tissue and is modulated into speech. The common electronic artificial larynx with armature motor as the sound source has serious radiation noise problems, unsatisfactory voice, mechanical speech, and low intelligibility.

[0003] The speech assistance system designed based on acoustic parametric array technology, that is, the electronic artificial larynx based on acoustic parametric array, uses an ultrasonic transducer as the excitation sound source, and the ultrasonic wave self-demodulates in the human tissue to generate a directional glottal wave signal. It can overcome the problem of radiation noise of the traditional electronic artificial larynx. However, due to the complexity of human tissue, the simple use of an array parametric array system cannot ensure that the parametric array sound field is focused at a specified position in the human larynx. Summary of the invention

[0004] The purpose of this application is to provide a speech assistance system based on phased focusing and a method for making and using the system, which can focus the sound field of an acoustic parametric array at a specified position in the human larynx.

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

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

[0007] A glottal wave pulse modulator is used to modulate the original pronunciation 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 received by it; the virtual sound source is located at a focal position; the focal position is the focal position of the ultrasonic transducer;

[0009] The phased array drive control system is used to control the transmission phase of each ultrasonic transducer when transmitting the modulated signal.

[0010] Optionally, a plurality of the ultrasonic transducers are arranged in a circle and are bilaterally symmetrical with respect to the sagittal plane of the human body.

[0011] Optionally, the phased-control focusing-based voice assistance system further includes: a power module;

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

[0013] Optionally, the phased-control focusing-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, the center frequency of each of the ultrasonic transducers is the same.

[0017] In a second aspect, the present application provides a phase determination method for a voice assistance system based on phased focusing, and the phase determination method for a voice assistance system based on phased focusing includes:

[0018] Obtain images of the neck;

[0019] determining a focal position of an ultrasonic transducer according to the neck image;

[0020] Determine the number and placement positions of ultrasonic transducers according to the neck image and the focal position;

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

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

[0023] In a third aspect, the present application provides a method for using a voice assistance system based on phased focus, and the method for using a voice assistance system based on phased focus includes:

[0024] Obtaining original pronunciation glottal wave signal;

[0025] Modulating the original vocalization glottal wave signal with a carrier signal that excites an ultrasonic transducer to obtain a modulated signal;

[0026] The modulation signal is input into a phased array drive control system to generate an ultrasonic wave focused at a focal position; the phased array drive control system controls each ultrasonic transducer to transmit the modulation signal, and controls the transmission phase of each ultrasonic transducer when transmitting the modulation signal; the transmission 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 vocalization glottal wave signal is modulated with a carrier signal for exciting an ultrasonic transducer to obtain a modulated signal, specifically comprising:

[0028] The original vocalization glottal wave signal and the carrier signal that excites the ultrasonic transducer are subjected to orthogonal amplitude modulation to obtain a modulated signal.

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

[0030] The present application provides a speech assistance system based on phased focusing and its manufacturing method and use method, the system includes: a glottal wave pulse modulator, a phased array drive control system and an acoustic parametric array; the glottal wave pulse modulator is used to modulate the original pronunciation glottal wave signal with the carrier signal of the excitation ultrasonic transducer to obtain a modulated signal; 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; the phased array drive control system is used to control the emission phase of each ultrasonic transducer when emitting the modulated signal. The present application uses a phased method to control the emission phase of the ultrasonic transducer so that the parametric array sound field is focused at a specified position of the human larynx. The present application controls the emission phase of each ultrasonic transducer to be the ultrasonic phase emitted by the virtual sound source located at the focusing position, so that the information emitted by these ultrasonic transducers can be focused on the focusing position. The present application can focus the sound field of the acoustic parametric array at a specified position of the human larynx. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0032] Figure 1 A schematic diagram of the structure of a voice assistance system based on phased focusing provided in Example 1 of the present application;

[0033] Figure 2A schematic diagram of the modulation process provided in Example 1 of the present application;

[0034] Figure 3 A schematic diagram of a preset envelope signal provided in Example 1 of the present application;

[0035] Figure 4 A schematic diagram of a modulation signal provided in Example 1 of the present application;

[0036] Figure 5 A schematic diagram of the working process of the phased array drive control system provided in Example 1 of the present application;

[0037] Figure 6 A schematic diagram of a dual-probe acoustic parametric array provided in Example 1 of the present application;

[0038] Figure 7 A schematic diagram of a multi-probe acoustic parametric array provided in Example 1 of the present application;

[0039] Figure 8 A schematic diagram of the power spectrum at the focus position when the dual transducers provided in the first embodiment of the present application transmit in phase;

[0040] Fig. 9 This is a schematic diagram of the power spectrum at the focus position when the dual transducers provided in Example 1 of the present application transmit in reverse phase.

[0041] Reference numerals:

[0042] Power module-1, glottal wave pulse modulator-2, phased array drive control system-3, acoustic parametric array-4. DETAILED DESCRIPTION

[0043] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0044] The existing speech assistance system based on acoustic parametric array technology, i.e., the electronic artificial larynx based on acoustic parametric array, uses an ultrasonic transducer as the excitation sound source, and the ultrasonic wave is self-demodulated in the human tissue to generate a directional glottal wave signal, which can overcome the problem of radiation noise of the traditional electronic artificial larynx.

[0045] However, the efficiency of converting the electronic artificial laryngeal ultrasound waves into glottal waves is low, and the conversion efficiency has been 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, due to the safety requirements of human equipment, there are limitations on the increase in the power of the driving signal, and there is a bottleneck in the conversion efficiency.

[0046] In addition, due to the complexity of human tissue, simply using an array-type parametric array system cannot ensure that the parametric array sound field is focused at a specified position in the human larynx. This application introduces phase modulation technology based on a phased array to effectively control the focusing position of each parametric array sound field, ensuring that the emitted ultrasonic wave is demodulated into a glottal wave at a specified position.

[0047] In order to make the above-mentioned objects, features and advantages of the present application more obvious and easy to understand, the present application is further described in detail below with reference to the accompanying drawings and specific implementation methods.

[0048] Embodiment 1:

[0049] In an exemplary embodiment, Figure 1 As shown, a speech assistance system based on phased focusing is provided, which includes: a glottal wave pulse modulator 2, a phased array drive control system 3 and an acoustic parameter array 4.

[0050] The glottal wave pulse modulator 2 is used to modulate the original glottal wave signal with the carrier signal of the excitation ultrasonic transducer to obtain a modulated signal, such as Figure 2 The glottal wave pulse modulator 2 uses digital modulation to perform amplitude modulation on the carrier signal and the original pronunciation glottal wave signal, and can perform single-sideband modulation or double-sideband modulation in MCU, DSP or FPGA, and the frequency range of the modulated signal is 20kHz to 200kHz.

[0051] The original glottal wave signal in this embodiment can come from the normal speech of the patient before the disease, or from other normal human speech close to the patient's pronunciation. The carrier signal that excites the ultrasonic transducer is the same as the center frequency of the ultrasonic transducer to be driven. The center frequency of the target ultrasonic transducer driven in this embodiment is 50kHz. The double-sideband modulation method is used in the MCU to modulate the glottal wave signal and the 50kHz sine wave signal.

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

[0053] s(t)=(A+m(t))cos(2πf c t);

[0054] Among them, m(t) is the 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 cis 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; the central frequency of each ultrasonic transducer is the same, 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, symmetrically on the sagittal plane of the human body.

[0056] Among them, setting the emission phase of the ultrasonic transducer can also be understood as the modulation signal driven by each transducer has an independent phase delay. The phased array drive control system 3 controls the phase delay of the modulation signal and amplifies its power to achieve phase-independent driving of each ultrasonic transducer unit. In this embodiment, 6 drive channels are used. The phase delay is added in the MCU, and after the delay, the DAC is controlled to convert the modulated digital signal into an analog signal output, and the power is amplified through the 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, and the axial angle between the two excitation sources is 60°. The driving phase delay of the two ultrasonic transducers controls the phase difference of the two carrier signals by 180°. The power spectrum at the focus position is calculated by simulation. When the phase of the modulated signal is the same and the two transducers are transmitted in phase, the power at the focus position is 87.51dB. The power spectrum is as follows: Figure 8 As shown in the figure, the phase difference of the modulated signal is 180°, that is, when the dual transducers transmit in anti-phase, the power at the focus position is 13.40dB, and the power spectrum is as follows: Fig. 9 As shown. By using the carrier phase control method, the energy of the difference frequency wave can be increased while suppressing the energy of the original frequency wave. (Here is a comparison. When the phases are the same, the two ultrasonic waves at the focus suppress each other. When the phase difference is 180°, the two ultrasonic waves are enhanced at the focus).

[0058] The step of determining the emission phase of the ultrasonic transducer includes:

[0059] 1. Determine the focal position based on the patient's neck CT image. It is generally located at the mucosa on the anterior surface of the trachea. Focusing at this location can cause the mucosa to vibrate and generate glottal waves.

[0060] 2. Design the number and position of ultrasonic transducers. Set 2-N ultrasonic transducers on the horizontal plane passing through the focal point. The transducers are arranged in a circle, symmetrically according to the sagittal plane of the human body, and cover the range of 60-180° in the front of the human neck (wherein, the method for determining the "range of 60-180° in the front of the neck" is to use a certain horizontal plane at the neck position as the plane coordinate axis, and the front of the human body as the Y axis, i.e. 90°). The position of the ultrasonic transducer on the human neck can be determined based on the CT image. (In this embodiment, there are two ultrasonic transducers based on sagittal symmetry, with an angle of 60°). Among them, the more ultrasonic transducers, the better, provided that they can be placed in the front of the human neck. The more ultrasonic transducers, the higher the conversion efficiency. When the acoustic parameter array 4 is a dual probe such as Figure 6 As shown, when the acoustic parameter array 4 is a multi-probe Figure 7 as shown.

[0061] 3. Use the time reversal algorithm to determine the transmission phase delay of each transducer (the phase difference in this embodiment is 180°). Time reversal algorithm: Place a virtual sound source at the focal position, which transmits ultrasonic signals to all directions. The ultrasonic phase emitted by the virtual sound source received by the ultrasonic transducer is the transmission phase of the ultrasonic transducer.

[0062] The voice assistance system is made based on the ultrasonic transducer position and phase delay determined by the above results.

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

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

[0065] The phased-control focusing-based voice assistance system also includes: a power amplifier: the power amplifier is used to amplify the power of the modulated signal.

[0066] Among them, the speech assistance system based on phased focusing in this embodiment uses the signal after the amplitude modulation of the normal speech glottal wave signal and the carrier sinusoidal signal, after filtering and amplitude conditioning, power amplification is performed, and the phase of the excitation signal is controlled to drive the ultrasonic transducer to emit focused ultrasonic waves. The ultrasonic wave of the ultrasonic transducer is self-demodulated into a glottal wave signal in the patient's body, so that the patient can speak normally.

[0067] This embodiment can generate audible sound waves in the head and neck tissue of the human body by using the focused acoustic parametric array 4, which can be provided with multiple ultrasonic transducers, thereby reconstructing the patient's sound source while making up for the shortcoming of insufficient glottal wave signal energy in the parametric array, and improving the conversion power of the parametric array sound field demodulated in the human body. Therefore, this embodiment can effectively reduce the energy of the original frequency sound field of the focused parametric array while improving the glottal wave signal energy.

[0068] Embodiment 2:

[0069] Based on the same inventive concept, the embodiment of the present application also provides a phase determination method for the above-mentioned voice assistance system based on phased focus. The method is similar to the implementation scheme recorded in the above-mentioned embodiment, so the specific limitations in one or more embodiments provided below can be found above. The phase determination method for the voice assistance system based on phased focus includes:

[0070] Step S1, obtaining a neck image. The neck image in this embodiment is a CT or MRI image of the neck, or may be a tomographic image of the neck.

[0071] Step S2: Determine the focus position of the ultrasonic transducer according to the neck image. In this embodiment, the focus position is the mucosa on the front surface of the trachea.

[0072] Step S3: determining the number and placement positions of ultrasonic transducers according to the neck image and the focal position.

[0073] Step S4, determining the emission phase of each ultrasonic transducer using a time inversion method according to the placement position and focal 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 focal position.

[0074] Embodiment three:

[0075] Based on the same inventive concept, the embodiment of the present application further provides a method for using the above-mentioned voice assistance system based on phased-control focusing, and the method for using the voice assistance system based on phased-control focusing includes:

[0076] Step A1: obtaining an original pronunciation glottal wave signal.

[0077] Step A2: performing orthogonal amplitude modulation on the original vocalization glottal wave signal and the carrier signal for exciting the ultrasonic transducer to obtain a modulated signal.

[0078] Step A3, inputting the modulated 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 transmit the modulated signal, and controls the transmission phase of each ultrasonic transducer when transmitting the modulated signal; the transmission 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, stored data, displayed data, 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 relevant data must comply with relevant regulations.

[0080] The technical features of the above embodiments may be arbitrarily combined. To make the description concise, 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 article uses specific examples to illustrate the principles and implementation methods of this application. The description of the above embodiments is only used to help understand the method and core ideas of this application. At the same time, for those skilled in the art, according to the ideas of this application, there will be changes in the specific implementation methods and application scope. In summary, the content of this specification should not be understood as limiting this application.

Claims

1. A voice assistance system based on phased focusing, characterized in that: The speech assistance system based on phased-control focusing comprises: a glottal wave pulse modulator, a phased-array drive control system and an acoustic parameter array; A glottal wave pulse modulator is used to modulate the original pronunciation glottal wave signal with the carrier signal that excites the ultrasonic transducer to obtain a modulated signal; 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 received by it; the virtual sound source is located at a focal position; the focal position is the focal position of the ultrasonic transducer; The phased array drive control system is used to control the transmission phase of each ultrasonic transducer when transmitting the modulated signal.

2. The phased focusing-based voice assistance system according to claim 1, characterized in that: The plurality of ultrasonic transducers are arranged in a circle and are bilaterally symmetrical with respect to the sagittal plane of the human body.

3. The phased focusing-based voice assistance system according to claim 1, characterized in that: The phased-control focusing-based voice assistance system further includes: a power module; The power supply module is used to supply power to the glottal wave pulse modulator, the phased array drive control system and the acoustic parametric array.

4. The phased focusing-based voice assistance system according to claim 1, characterized in that: The phased-control focusing-based voice assistance system further includes: a power amplifier: The power amplifier is used to amplify the power of the modulated signal.

5. The phased focusing-based voice assistance system according to claim 1, characterized in that: The frequency range of the modulation signal is 20kHz to 200kHz.

6. The phased focusing-based voice assistance system according to claim 1, characterized in that: The central frequency of each of the ultrasonic transducers is the same.

7. A phase determination method for a speech assistance system based on phased focusing, characterized in that: The phase determination method of the speech assistance system based on phased focusing includes: Obtain images of the neck; determining a focal position of an ultrasonic transducer according to the neck image; Determine the number and placement positions of ultrasonic transducers according to the neck image and the focal position; The emission phase of each ultrasonic transducer is determined by using a time inversion method according to the placement position and focusing position of the ultrasonic transducer; the emission phase of each ultrasonic transducer is the ultrasonic phase emitted by a virtual sound source it receives; and the virtual sound source is located at the focusing position.

8. The phase determination method of the speech assistance system based on phased focusing according to claim 7, characterized in that: The focal position is the mucosa on the front surface of the trachea.

9. A method for using a voice assistance system based on phased focusing, characterized in that: The method for using the phased-focus-based voice assistance system includes: Obtaining original pronunciation glottal wave signal; Modulating the original vocalization glottal wave signal with a carrier signal that excites an ultrasonic transducer to obtain a modulated signal; The modulation signal is input into a phased array drive control system to generate an ultrasonic wave focused at a focal position; the phased array drive control system controls each ultrasonic transducer to transmit the modulation signal, and controls the transmission phase of each ultrasonic transducer when transmitting the modulation signal; the transmission 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.

10. The method for using the phased focusing-based voice assistance system according to claim 9, characterized in that: The original vocalization glottal wave signal is modulated with a carrier signal for exciting an ultrasonic transducer to obtain a modulated signal, specifically comprising: The original vocalization glottal wave signal and the carrier signal that excites the ultrasonic transducer are subjected to orthogonal amplitude modulation to obtain a modulated signal.

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