Methods, procedures, equipment, and storage media for calibrating the amplitude and phase consistency of parametric arrays.

Abstract

This invention belongs to the field of nonlinear acoustics technology, specifically relating to a method, program, equipment, and storage medium for calibrating the amplitude and phase consistency of parametric arrays. This invention determines and compensates for the difference-frequency amplitude and phase response of the high-frequency acoustic waves emitted by each array element, thereby enabling the calibration of the amplitude and phase consistency of parametric arrays in various experimental scenarios such as water tanks and anechoic chambers. This invention exhibits high robustness to installation errors, and the calibrated array elements possess a more consistent difference-frequency amplitude and phase response. The invention has a simple implementation, is applicable to various experimental scenarios, and provides necessary pre-calibration for beamforming of parametric arrays, possessing high application value.

Description

Technical Field

[0001] This invention belongs to the field of nonlinear acoustics technology, specifically relating to the method, program, equipment, and storage medium for calibrating the amplitude and phase consistency of parametric arrays. Background Technology

[0002] Parametric arrays are an important research direction in the field of nonlinear acoustics. When a transducer emits high-frequency, large-amplitude sound waves, due to the acoustic nonlinearity of the medium, difference-frequency sound waves will accumulate in space. Due to the low-frequency and highly directive characteristics of difference-frequency sound waves, parametric arrays have cutting-edge applications in fields such as shallow seabed profiling, active noise control, and nondestructive testing of materials.

[0003] In recent years, researchers have utilized the high directivity of parametric arrays to create arrays that flexibly form local sound fields or sound beams with specific distributions. To avoid the influence of initial amplitude and phase differences between array elements on the sound field distribution, the amplitude and phase consistency of the parametric array needs to be calibrated. Although researchers have proposed consistency calibration methods for complex test scenarios such as confined spaces and near-field conditions, there is currently a lack of array amplitude and phase consistency calibration methods specifically for parametric arrays. Summary of the Invention

[0004] The purpose of this invention is to provide a method, program, device and storage medium for calibrating the amplitude and phase consistency of a parametric array. By measuring the amplitude and phase response of the high-frequency sound waves emitted by each array element in the array of the parametric array, the amplitude and phase response of the difference frequency sound waves is determined and compensated, which can realize the amplitude and phase consistency calibration of the parametric array in multiple test scenarios such as water tanks and anechoic chambers.

[0005] The method for calibrating the amplitude and phase consistency of a parametric array includes the following steps:

[0006] Arrange a signal generator, power amplifier, parametric array, microphone, and electroacoustic data acquisition unit; the parametric array and microphone are spaced a certain distance apart.

[0007] The signal generator produces a high-frequency modulated signal based on two high-frequency primary waves. After passing through a power amplifier, the signal is emitted by a certain element in the parametric array, and the microphone receives the sound signal.

[0008] The electroacoustic data acquisition unit synchronously acquires the high-frequency modulation signal generated by the signal generator and the acoustic signal received by the microphone after being transmitted by the array element, and processes them together to calculate the transmission voltage amplitude and phase response of the two high-frequency original waves, and calculates the modulation amplitude response and phase response of the array element.

[0009] Repeat the above process for each element in the parametric array to obtain the modulation amplitude response and phase response of each element in the parametric array, and calculate the mean of the modulation phase response and the minimum of the modulation amplitude response of each element in the parametric array.

[0010] The amplitude and phase of the transmit voltage of each element in the parametric array are compensated. The difference between the modulation amplitude response of the element and the minimum value of the modulation amplitude response of each element is used as the transmit voltage amplitude compensation value of the element. The difference between the modulation phase response of the element and the mean value of the modulation phase response of each element is used as the transmit voltage phase compensation value of the element, thus completing the amplitude and phase consistency calibration of the parametric array.

[0011] Furthermore, the distance between the array of the parametric array and the microphone is greater than the Rayleigh distance for high-frequency waves.

[0012] Furthermore, the signal generator generates a high-frequency modulation signal s0 based on the high-frequency original waves p1 and p2, which is then amplified by a power amplifier and transmitted by the i-th element of the parametric array. The microphone receives the sound signal s0. i .

[0013] Furthermore, the signal generator generates a high-frequency modulation signal s0 based on the high-frequency original waves p1 and p2, and the specific modulation method is as follows:

[0014] s0(t)=w1 sin(2πf1t+ψ1)+w2sin(2πf2t+ψ2)

[0015] Where w1, f1, and ψ1 are the modulation coefficients, transmission frequency, and initial phase of the high-frequency original wave p1; and w2, f2, and ψ2 are the modulation coefficients, transmission frequency, and initial phase of the high-frequency original wave p2.

[0016] Furthermore, the electroacoustic data acquisition device synchronously acquires the high-frequency modulation signal s0 generated by the signal generator and the acoustic signal s received by the microphone. i For s0 and s i By combining the processing, the amplitude response of the transmitted voltage of the high-frequency original wave p1 is calculated. Phase response Transmit voltage amplitude response of the high-frequency original wave p2 Phase response

[0017] Furthermore, the modulation amplitude response of the i-th element in the array of the parametric array Phase response The calculation method is as follows:

[0018]

[0019]

[0020] Furthermore, the mean value of the modulation phase response of each element in the parametric array is calculated. Obtain the minimum value of the modulation amplitude response of each element in the parametric array. For the i-th element in the parametric array, the transmit voltage amplitude compensation value is... Transmit voltage phase compensation value

[0021] A computer device / apparatus / system includes a memory, a processor, and a computer program stored in the memory, wherein the processor executes the computer program to implement the steps of the above-described method for calibrating the amplitude and phase consistency of a parametric array.

[0022] A computer-readable storage medium having a computer program / instructions stored thereon, which, when executed by a processor, implements the steps of the array amplitude-phase consistency calibration method for the parametric array described above.

[0023] A computer program product includes a computer program / instructions that, when executed by a processor, implement the steps of the array amplitude-phase consistency calibration method for the parametric array described above.

[0024] The beneficial effects of this invention are as follows:

[0025] This invention determines and compensates for the difference-frequency acoustic wave amplitude and phase response by measuring the high-frequency acoustic wave amplitude and phase response emitted by each array element, thereby enabling the calibration of the array amplitude and phase consistency of parametric arrays in various test scenarios such as water tanks and anechoic chambers. This invention exhibits high robustness to installation errors, and the calibrated array elements possess a more consistent difference-frequency amplitude and phase response. The invention is simple to implement, applicable to various test scenarios, and provides necessary pre-calibration for beamforming of parametric arrays, demonstrating high application value. Attached Figure Description

[0026] Figure 1 This is a schematic diagram showing the arrangement and connection of each component when performing array amplitude and phase consistency calibration of the parametric array according to the present invention.

[0027] Figure 2 This is a flowchart of the joint processing procedure for the difference frequency amplitude and phase response test.

[0028] Figure 3 This is a schematic diagram of the difference frequency directivity formed by the array of calibrated parametric arrays.

[0029] Figure 4 This is a test data table for the difference frequency amplitude and phase response in an embodiment of the present invention. Detailed Implementation

[0030] The present invention will now be further described with reference to the accompanying drawings.

[0031] This invention provides a method for calibrating the amplitude and phase consistency of a parametric array. By measuring the amplitude and phase response of the high-frequency sound waves emitted by each array element in the array of the parametric array, the amplitude and phase response of the difference frequency sound waves is determined and compensated. This method can achieve the calibration of the amplitude and phase consistency of the parametric array in various test scenarios such as water tanks and anechoic chambers.

[0032] For a parametric array, the amplitude and phase response of the difference-frequency acoustic wave can be expressed as: the modulation amplitude and phase response of the two high-frequency acoustic waves multiplied by the amplitude and phase response A0 of the nonlinear acoustic channel. And A0, Since the response of the array elements in the parametric array is independent of the transmission system response, the array consistency can be calibrated by modulating the amplitude and phase response.

[0033] The method for calibrating the amplitude and phase consistency of a parametric array includes the following steps:

[0034] Step 1: Arrange the signal generator, power amplifier, parametric array, microphone, and electroacoustic data acquisition unit; the parametric array and microphone are spaced a certain distance apart; initialize i = 1;

[0035] Step 2: The signal generator produces a high-frequency modulation signal s0 based on the high-frequency original waves p1 and p2. After passing through a power amplifier, it is emitted by the i-th element in the parametric array, and the microphone receives the sound signal s0. i The high-frequency modulated signal s0 generated by the signal generator and the acoustic signal s received by the microphone are synchronously acquired by the electroacoustic data acquisition device. i ;

[0036] s0(t)=w1 sin(2πf1t+ψ1)+w2 sin(2πf2t+ψ2)

[0037] Where w1, f1, and ψ1 are the modulation coefficients, transmission frequency, and initial phase of the high-frequency original wave p1; and w2, f2, and ψ2 are the modulation coefficients, transmission frequency, and initial phase of the high-frequency original wave p2.

[0038] Step 3: Compare s0 and s i By combining the processing, the amplitude response of the transmitted voltage of the high-frequency original wave p1 is calculated. Phase response Transmit voltage amplitude response of the high-frequency original wave p2 Phase response

[0039] Step 4: Calculate the modulation amplitude response of the i-th element in the parametric array. With modulation phase response

[0040]

[0041]

[0042] Step 5: If i < N, where N is the total number of array elements in the parametric array, then let i = i + 1 and return to step 2; otherwise, proceed to step 6.

[0043] Step 6: Calculate the mean value of the modulation phase response of each element in the parametric array. Obtain the minimum value of the modulation amplitude response of each element in the parametric array.

[0044] Step 7: Compensate for the amplitude and phase of the transmit voltage of each element in the parametric array to complete the amplitude and phase consistency calibration of the parametric array.

[0045] Transmit voltage amplitude compensation value for:

[0046] Transmit voltage phase compensation value for:

[0047] Example 1:

[0048] Taking an underwater acoustic parametric array as an example, the amplitude and phase consistency of each array element is calibrated in an anechoic water tank. The test platform is shown in the attached figure. Figure 1 The underwater acoustic parametric array consists of two 65kHz high-frequency transmitting transducers with a transmission difference frequency of 4kHz. (Based on the attached...) Figure 2 The combined processing flow test of the difference frequency amplitude phase response.

[0049] Considering the unavoidable installation errors in actual measurements, since the microphone is already located on the main lobe of the beam, and The influence of the transmit / receive distance error Δz is k d Δz (difference frequency wavenumber k) d =2πf d / c, where c is the velocity of sound in the propagation medium), therefore this calibration method has high robustness to installation errors. The difference frequency amplitude and phase response test data before and after calibration are shown below. Figure 4 As can be seen, the calibrated array elements have a more consistent difference frequency amplitude and phase response. The difference frequency directivity of the array elements after calibration is shown in the attached figure. Figure 3 The designed beam shape is satisfied. It is evident that the array amplitude and phase consistency calibration method of the parametric array designed in this invention is effective, even considering the influence of installation errors in actual measurements.

[0050] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A method for calibrating the amplitude and phase consistency of a parametric array, characterized in that: Arrange a signal generator, power amplifier, parametric array, microphone, and electroacoustic data acquisition unit; the parametric array and microphone are spaced a certain distance apart. The signal generator is based on two high-frequency primary waves. and Generate high-frequency modulation signal After passing through a power amplifier, the first parameter in the array of parametric arrays... The array element transmits the sound signal, and the microphone receives the sound signal. ; in, , , High-frequency original wave The modulation coefficient, transmission frequency, and initial phase; , , High-frequency original wave The modulation coefficient, transmission frequency, and initial phase; The electroacoustic data acquisition device synchronously acquires the high-frequency modulated signal generated by the signal generator. With the passing of the first The sound signal received by the microphone after the array element is transmitted ,right and Joint processing was used to calculate the original high-frequency wave. transmit voltage amplitude response Phase response High-frequency original wave transmit voltage amplitude response Phase response Calculate the first Modulation amplitude response of array elements Phase response ; ， Repeat the above process for each element in the parametric array to obtain the modulation amplitude response and phase response of each element in the parametric array, and calculate the mean of the modulation phase response of each element in the parametric array. Minimum value of modulation amplitude response ; The total number of array elements in the parametric array; The transmit voltage amplitude and phase of each element in the parametric array are compensated, and the modulation amplitude response of that element is obtained. Minimum value of the modulation amplitude response of each array element The difference is used as the compensation value for the transmit voltage amplitude of the array element. ,Right now ; the modulation phase response of the array element The mean of the modulation phase response of each array element The difference is used as the phase compensation value of the transmit voltage of the array element. ,Right now Complete the array amplitude and phase consistency calibration of the parametric array.

2. The array amplitude and phase consistency calibration method for parametric arrays according to claim 1, characterized in that: The distance between the parametric array and the microphone is greater than the Rayleigh distance for high-frequency waves.

3. A computer device, comprising a memory, a processor, and a computer program stored in the memory, characterized in that: The processor executes the computer program to implement the steps of the method according to any one of claims 1 to 2.

4. A computer-readable storage medium having a computer program stored thereon, characterized in that: When executed by a processor, the computer program implements the steps of the method according to any one of claims 1 to 2.

5. A computer program product, comprising computer instructions, characterized in that: When executed by a processor, the computer instructions implement the steps of the method according to any one of claims 1 to 2.

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