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CN-121985260-A - Ultrasonic directional sounding system and method based on multi-order fundamental frequency multiplication and compensation

CN121985260ACN 121985260 ACN121985260 ACN 121985260ACN-121985260-A

Abstract

The invention provides an ultrasonic directional sound production system and method based on multi-order fundamental frequency multiplication and compensation, wherein the ultrasonic directional sound production system comprises an audible sound receiving module for acquiring the fundamental frequency of audible sound A multi-order ultrasonic fundamental frequency generation module for generating multi-order ultrasonic fundamental frequency signals An audible fundamental frequency multiplication module for obtaining audible fundamental frequencies of different frequency bands Frequency multiplication order of (2) And audible fundamental frequencies of different frequency bands are used According to the corresponding frequency multiplication order Frequency multiplication to obtain a frequency-multiplied signal A modulation module for receiving the frequency-multiplied signal And frequency-doubling the signal Modulated to a fundamental frequency signal In order to obtain multi-frequency band composite modulation ultrasonic signals The compensation calibration module is used for compositely modulating ultrasonic signals in multiple frequency bands Signal compensation is carried out to obtain compensated composite modulated ultrasonic signals A transducer module for receiving the compensated composite modulated ultrasonic signal To form a sound field 。

Inventors

  • YU HAO
  • LIU XIAOTAN

Assignees

  • 上海瑞和锋电子科技有限公司

Dates

Publication Date
20260505
Application Date
20260127

Claims (10)

  1. 1. An ultrasonic directional sound production system based on multi-order fundamental frequency multiplication and compensation, which is characterized by comprising: An audible sound receiving module for obtaining audible sound fundamental frequency ; A multi-order ultrasonic fundamental frequency generation module for generating multi-order ultrasonic fundamental frequency signals : , Wherein, the For the initial fundamental frequency, For the fundamental frequency to be equally spaced, For the baseband channel number, ; The audible sound fundamental frequency multiplication module is in communication connection with the multi-order ultrasonic fundamental frequency generation module and the audible sound receiving module and is used for acquiring audible sound fundamental frequencies of different frequency bands Frequency multiplication order of (2) And audible fundamental frequencies of different frequency bands are used According to the corresponding frequency multiplication order Frequency multiplication to obtain a frequency-multiplied signal , , The frequency multiplication order The method comprises the following steps: , Wherein, the For the frequency of the ultrasonic wave of interest, ; The modulation module is in communication connection with the audible sound fundamental frequency multiplication module and is used for receiving the frequency multiplication signal And frequency-doubling the signal Modulated to a fundamental frequency signal In order to obtain multi-frequency band composite modulation ultrasonic signals ; The compensation calibration module is in communication connection with the modulation module and is used for modulating the ultrasonic signals in a multi-frequency band composite mode Signal compensation is carried out to obtain compensated composite modulated ultrasonic signals ; The transducer module is in communication connection with the compensation calibration module and is used for receiving the compensated composite modulation ultrasonic signals To form a sound field The transducer module comprises transducers arranged in an array and an array topology optimization unit used for correcting each transducer unit, and the array topology optimization unit is used for outputting the weight coefficient of each transducer unit The method comprises the following steps: , Wherein, the For the dimensions of the array, Is a P-order cut-ratio snow auxiliary polynomial, For the m-th row and n-th column transducer spacing, For the beam pointing angle, Is an ultrasonic wavelength.
  2. 2. The ultrasonic directional sound production system of claim 1, wherein in the multi-stage ultrasonic fundamental frequency generation module, At a frequency of 20kHz, the frequency of the laser beam is, Is 10kHz.
  3. 3. The ultrasonic directional sound production system of claim 1, wherein the audible fundamental frequency multiplication module comprises an audible fundamental frequency segmentation unit for dividing an audible fundamental frequency Dividing into high frequency band, middle and low frequency bands and very low frequency band according to frequency to match different frequency multiplication orders ; The high frequency range is less than or equal to 10kHz Not more than 20kHz, matching frequency multiplication order k=2, and medium frequency band not more than 5kHz <10KHz, matching frequency multiplication order k=4, and middle and low frequency bands of 2.5kHz less than or equal to <5KHz, matching frequency multiplication order k=8, very low band <2.5KHz, matching frequency multiplication order k=8.
  4. 4. The ultrasonic directional sound production system of claim 3, wherein the audible fundamental frequency multiplication module comprises an ultra-low frequency band signal processing unit for receiving the ultra-low frequency band audible fundamental frequency And processing to obtain a composite transmission signal in the very low frequency range The ultra-low frequency band composite transmitting signal The method comprises the following steps: , Wherein, the Audible fundamental frequency of very low frequency band after 8-order frequency multiplication , The ultrasonic carrier signal is an ultrasonic carrier signal with the frequency of 20kHz, and the carrier power ratio of the ultrasonic carrier signal is 15% -20%.
  5. 5. The ultrasonic directional sound production system of claim 1, wherein the compensation calibration module comprises a phase compensation unit, the phase compensation amount of the phase compensation unit The method comprises the following steps: , Wherein, the As a reference phase to the reference phase of the reference signal, For the actual measured phase of the signal, As the amount of phase shift caused by the temperature, Is the amount of phase shift caused by the propagation distance.
  6. 6. The ultrasonic directional sound generating system according to claim 1, wherein the compensation calibration module comprises a temperature compensation unit and a humidity compensation unit, the temperature compensation amount of the temperature compensation unit The method comprises the following steps: , Wherein, the Is the temperature phase coefficient , In order to be at the temperature of the environment, Is 25 ℃ of standard temperature; Amplitude attenuation compensation coefficient of the humidity compensation unit The method comprises the following steps: , Wherein RH is the ambient relative humidity.
  7. 7. The ultrasonic directional sound production system according to claim 1, wherein the distance dmn between transducers arranged in an array in the transducer module satisfies non-uniform distribution, and the emission sound pressure level of a single transducer is more than or equal to 110dB and the resonance frequency is 40kHz at a test distance of 1 m.
  8. 8. The ultrasonic directional sound production system of claim 1, further comprising a sound field feedback module in communication with the transducer module for capturing a sound field Is of fundamental wave amplitude of (2) The h order harmonic amplitude Highest harmonic order And calculates the harmonic distortion ratio The method comprises the following steps: , Wherein, the For the fundamental amplitude of the sound field S, For the H harmonic amplitude, H is the highest harmonic frequency, and the acquisition period is 10ms.
  9. 9. An ultrasonic directional sounding method based on multi-order fundamental frequency multiplication and compensation is characterized by comprising the following steps of: s1, obtaining audible fundamental frequency ; S2, generating n paths of arithmetic difference multi-order ultrasonic fundamental frequency signals ; S3, receiving audible sound fundamental frequency Multi-order ultrasonic fundamental frequency signal Calculating audible fundamental frequencies of different frequency bands Frequency multiplication order of (2) ; S4, identifying fundamental frequency of each audible sound Belonging to frequency band, matching corresponding frequency multiplication order And frequency-doubling to obtain frequency-doubled signal ; S5, multiplying the frequency signal Modulated to a fundamental frequency signal And obtain multi-frequency band composite modulation ultrasonic signal ; S6, compositely modulating ultrasonic signals for multiple frequency bands Signal compensation is carried out, and a compensated composite modulation ultrasonic signal is obtained ; S7, compounding the compensated composite modulation ultrasonic signal And (3) inputting the ultrasonic wave beams into the transducers arranged in the array, correcting each transducer unit at the same time, and forming a sound field S by directional emission of the required scene.
  10. 10. The ultrasonic directional sounding method of claim 9, wherein said step S7 further comprises, after said step of: collecting and analyzing data of sound field S to calculate harmonic distortion rate : , Wherein, the For the fundamental amplitude of the sound field S, The H harmonic amplitude is the highest harmonic frequency, and the acquisition period is 10ms; Collecting and analyzing data of the sound field S to calculate a sidelobe sound pressure level P, wherein the collecting period is 10ms; If it is Or P > -20dB, then return to S4 to re-tune the audible fundamental frequency Frequency multiplication order Matching is carried out; If it is Or P 20DB, then the current transmit state is maintained.

Description

Ultrasonic directional sounding system and method based on multi-order fundamental frequency multiplication and compensation Technical Field The invention relates to the technical field of ultrasonic sound production, in particular to an ultrasonic directional sound production system and method based on multi-order fundamental frequency multiplication and compensation. Background At present, in the application field of ultrasonic sound production technology, such as public broadcasting, vehicle-mounted directional voice, exhibition hall directional explanation and other scenes, the ultrasonic sound production technology of high-precision directional sound production is required. In the prior art, the directional sounding technology is based on the parametric array principle, audible sound signals are modulated through ultrasonic carrier waves, and audible sound demodulation is completed by utilizing an air nonlinear effect, so that directional propagation of sound waves is realized, but the technology has three core defects: The modulation mode is limited in that in the prior art, a single frequency ultrasonic carrier wave (such as 40 kHz) is mostly adopted, the single modulation of the fundamental frequency and the carrier wave is easy to excite higher harmonic waves, the harmonic distortion rate is generally more than or equal to 15 percent, the audible sound reduction degree is extremely low, and the high-quality audio transmission requirement cannot be met; the array topology has the defects that the transducer array is in a symmetrical regular layout, the sound pressure level of beam sidelobes is more than or equal to-10 dB, obvious noise interference exists outside a directional area, and the acoustic pollution is easy to cause in the scenes such as a quiet exhibition hall, a vehicle-mounted cabin and the like; The scene suitability is poor, modulation parameters are not dynamically adjusted according to factors such as environment temperature and humidity, propagation distance and the like, the sound pressure level attenuation rate of low-frequency band (< 1 kHz) audible sound is more than or equal to 2dB/m, the full coverage of 20 kHz-160 kHz ultrasonic wave bands cannot be realized by a single frequency multiplication order, and the complex scene adaptation capability is insufficient. Therefore, the ultrasonic directional propagation technology in the prior art has the problems of high distortion rate, large side lobe interference, incomplete frequency band coverage and the like, and has larger technical limitation. Disclosure of Invention The invention aims to provide an ultrasonic directional sounding system and method based on multi-order fundamental frequency multiplication and compensation. In order to solve the above problems, the present invention provides an ultrasonic directional sound generating system based on multi-order fundamental frequency multiplication and compensation, which is characterized in that the ultrasonic directional sound generating system comprises: An audible sound receiving module for obtaining audible sound fundamental frequency ; A multi-order ultrasonic fundamental frequency generation module for generating multi-order ultrasonic fundamental frequency signals: , Wherein, the For the initial fundamental frequency,For the fundamental frequency to be equally spaced,For the baseband channel number,; The audible sound fundamental frequency multiplication module is in communication connection with the multi-order ultrasonic fundamental frequency generation module and the audible sound receiving module and is used for acquiring audible sound fundamental frequencies of different frequency bandsFrequency multiplication order of (2)And audible fundamental frequencies of different frequency bands are usedAccording to the corresponding frequency multiplication orderFrequency multiplication to obtain a frequency-multiplied signal, , The frequency multiplication orderThe method comprises the following steps: , Wherein, the For the frequency of the ultrasonic wave of interest,; The modulation module is in communication connection with the audible sound fundamental frequency multiplication module and is used for receiving the frequency multiplication signalAnd frequency-doubling the signalModulated to a fundamental frequency signalIn order to obtain multi-frequency band composite modulation ultrasonic signals; The compensation calibration module is in communication connection with the modulation module and is used for modulating the ultrasonic signals in a multi-frequency band composite modeSignal compensation is carried out to obtain compensated composite modulated ultrasonic signals; The transducer module is in communication connection with the compensation calibration module and is used for receiving the compensated composite modulation ultrasonic signalsTo form a sound fieldThe transducer module comprises transducers arranged in an array and an array topology optimization uni