Calibration system and method of implantable middle ear sensor

Abstract

The invention belongs to the field of acoustic signal testing, and particularly discloses a calibration system and method of an implantable middle ear sensor, the calibration system comprises an acoustic generating device, a sensor mounting block, an acoustic measuring device and a signal acquisition and analysis device.The acoustic generating device is used for generating a vibration signal; the sensor mounting block is mounted on the acoustic generation device, simulates an auditory ossicle structure and is used for mounting an implantable middle ear sensor to be tested; the acoustic measurement device is used for measuring the amplitude of the implantable middle ear sensor to obtain a displacement signal; and the signal acquisition and analysis device is used for acquiring a voltage signal of the implantable middle ear sensor and a displacement signal of the acoustic measurement device, and calibrating the performance of the implantable middle ear sensor based on the voltage signal and the displacement signal. The performance of the implantable middle ear sensor can be calibrated in advance, and the risk that the sensor goes wrong after implantation is reduced.

Description

Technical Field

[0001] The present invention belongs to the field of acoustic signal testing, and more specifically, relates to a calibration system and method for an implantable middle ear sensor. Background Art

[0002] The fully implantable cochlear implant is a new type of hearing restoration device that is completely implanted inside the patient's body without any external equipment. Different from traditional cochlear implants, the fully implantable cochlear implant uses a highly sensitive acoustic sensor in the middle ear cavity to receive sound and convert it into an electrical signal to directly stimulate the cochlea and auditory nerve. It eliminates the need for external equipment, making the appearance of the wearer the same as that of ordinary people, thus improving the acceptance and quality of life of patients and having broad application prospects. However, so far, the product is still in the stage of mainly research and development, and its key technology is the implantable middle ear sensor. Due to the small internal space and precise internal structure of the human middle ear system, there are strict restrictions on the size of the sensor itself. At the same time, due to the small vibration amplitude and large frequency change range of the ossicular chain itself, higher requirements are put forward for the precise measurement ability of the sensor.

[0003] Currently, there are several types of micro implantable auditory signal sensors in the research and development stage. For implantable sensors, their performance calibration and testing are a key link in the research and development process. Through calibration testing, specific parameters of the sensor performance can be obtained during the research and development process, providing an expectation for the performance that can be obtained after implantation, and making improvements to the sensor performance. At the same time, for the characteristics of implantable sensors, biocompatibility and electromagnetic shielding tests need to be carried out before implantation to avoid infection problems caused by biological incompatibility that may occur after implantation, and interference problems that may occur in a complex electromagnetic environment.

[0004] Currently, the calibration methods used for implantable middle ear sensors mostly use traditional sensor calibration methods and do not make specific improvements for the narrow and complex implant environment in the middle ear and the characteristics of auditory sensors. At the same time, using traditional sound generation platforms, more attention is paid to the performance of the sensor itself, and the sensor installation device is not designed according to the situation after implantation, resulting in the inability to better restore the vibration conditions generated on the eardrum and ossicles under the action of real sound inside the middle ear, thus making it impossible to give an accurate value for the performance of the sensor after implantation, increasing the trial-and-error cost during the research and development process of the sensor, and at the same time increasing the risk of problems with the sensor after being implanted into the patient's body. Therefore, for implantable middle ear sensors, a dedicated calibration system and calibration method need to be developed to systematically evaluate the implant performance of the sensor and predict the signals after implantation. Summary of the Invention

[0005] In view of the above deficiencies or improvement requirements of the prior art, the present invention provides a calibration system and method for an implantable middle ear sensor, aiming to pre-calibrate the performance of the implantable middle ear sensor and reduce the risk of problems occurring in the sensor after implantation.

[0006] To achieve the above object, according to one aspect of the present invention, a calibration system for an implantable middle ear sensor is proposed, including an acoustic generating device, a sensor mounting block, an acoustic measuring device, and a signal acquisition and analysis device, wherein:

[0007] The acoustic generating device is used to generate vibration signals;

[0008] The sensor mounting block is mounted on the acoustic generating device, and this sensor mounting block simulates the ossicular chain structure and is used to mount the implantable middle ear sensor to be tested;

[0009] The acoustic measuring device is used to measure the amplitude of the implantable middle ear sensor to obtain a displacement signal;

[0010] The signal acquisition and analysis device is used to collect the voltage signal of the implantable middle ear sensor and the displacement signal of the acoustic measuring device, and calibrate the performance of the implantable middle ear sensor based on the voltage signal and the displacement signal.

[0011] As a further preference, the acoustic generating device includes a speaker, and the sensor mounting block is mounted on the diaphragm of the speaker; the acoustic measuring device is a laser displacement sensor.

[0012] As a further preference, it further includes a mounting device, and the mounting device includes an optical measurement platform and a speaker mounting block and a laser displacement sensor mounting block mounted on the optical measurement platform, and the speaker mounting block and the laser displacement sensor mounting block are respectively used to mount and fix the speaker and the laser displacement sensor.

[0013] As a further preference, the sensor mounting block, the speaker mounting block, and the laser displacement sensor mounting block are all made by 3D printing.

[0014] As a further preference, the surface of the diaphragm of the speaker is circular, and its diameter is 10 mm to 50 mm.

[0015] According to another aspect of the present invention, a calibration method based on the above calibration system for an implantable middle ear sensor is provided, including the following steps:

[0016] The acoustic generating device generates vibration signals, and the implantable middle ear sensor to be tested follows the vibration;

[0017] Collect the voltage signal and the displacement signal of the implantable middle ear sensor;

[0018] Based on voltage signals and displacement signals, the performance calibration of the implantable middle ear sensor is achieved.

[0019] As a further preference, the acoustic generating device generates vibration signals according to the input sound signals, and the sound signals are swept-frequency sound signals, single-frequency sound signals or voice sound signals.

[0020] As a further preference, when the sound signal is a single-frequency sound signal, the performance calibration of the implantable middle ear sensor includes:

[0021] Converting the displacement signal into an acceleration signal, and performing frequency-domain processing on the voltage signal and the acceleration signal;

[0022] Based on the voltage signal after frequency-domain processing, the signal-to-noise ratio parameters of the implantable middle ear sensor at each single frequency are obtained; the voltage signal and the acceleration signal after frequency-domain processing are normalized to obtain the ratio of the voltage signal to the acceleration signal at different frequencies, so as to obtain the sensitivity of the implantable middle ear sensor.

[0023] As a further preference, when the sound signal is a swept-frequency sound signal, the performance calibration of the implantable middle ear sensor includes: performing frequency-domain processing on the voltage signal, and obtaining the dynamic frequency characteristics of the implantable middle ear sensor based on the voltage signal after frequency-domain processing;

[0024] When the sound signal is a voice sound signal, the performance calibration of the implantable middle ear sensor includes: obtaining the response of the implantable middle ear sensor under complex frequency input based on the voltage signal, and measuring the ability of the implantable middle ear sensor to restore complex sound signals after actual implantation.

[0025] As a further preference, before calibration, the amplitudes of the sound signals at each frequency are adjusted in advance, including:

[0026] The sound signal is converted into a vibration signal and output through the acoustic generating device, and the implantable middle ear sensor to be tested follows the vibration; the amplitude of the implantable middle ear sensor is measured through the acoustic measuring device to obtain the displacement signal; the amplitude of the sound signal is adjusted to make the displacement signal consistent with the vibration displacement signal of the middle ear in the human body at the corresponding frequency measured.

[0027] Generally speaking, compared with the prior art through the above technical solutions conceived by the present invention, the following technical advantages are mainly possessed:

[0028] 1. The present invention simulates the ossicle structure through the sensor mounting block, so as to better simulate the state after the sensor is implanted into the ossicular chain. Combining the setting of the speaker and the laser displacement sensor, the implant installation performance of the sensor is predicted, and the implantable middle ear sensor can be calibrated in multiple aspects by inputting various types of sound signals, thereby reducing the risk of problems with the sensor after implantation into the body.

[0029] 2. The design of the external installation device ensures the accuracy and precision of the measurement device used, and ensures that each component can work within the rated working range. At the same time, the overall calibration system is installed on the optical experiment platform, reducing the interference of the external environment on the system and also reducing the interference on the sensor itself; meanwhile, it is beneficial to fix the positions between the components, achieving an overall protection effect.

[0030] 3. By using a laser displacement sensor to detect the displacement signal of the sensor, the vibration condition of the sensor installation device can be obtained in real time. Thus, by adjusting the amplitude of the input vibration signal at each frequency, the vibration signal received by the sensor can be made consistent with the signal received in the real environment after implantation. By this method, the structure of the sensor installation device can be greatly simplified, enabling it to achieve the effect through a speaker and simulating the real implantation environment as much as possible. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 It is a schematic structural diagram of the calibration system for an implantable middle ear sensor according to an embodiment of the present invention;

[0032] Figure 2 It is a framework diagram of the calibration method for an implantable middle ear sensor according to an embodiment of the present invention;

[0033] Figure 3 It is a schematic diagram of sweep frequency calibration in an embodiment of the present invention;

[0034] Figure 4 It is a schematic diagram of single frequency calibration in an embodiment of the present invention;

[0035] Figure 5 It is a schematic diagram of voice calibration in an embodiment of the present invention.

[0036] In all the drawings, the same reference numerals are used to represent the same elements or structures, where: 1 - optical measurement platform, 2 - connecting piece, 3 - speaker mounting block, 4 - speaker, 5 - sensor mounting block, 6 - laser displacement sensor mounting block, 7 - laser displacement sensor. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0037] In order to make the objectives, technical solutions and advantages of the present invention clearer, the present invention will be further described in detail below with reference to the drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention. In addition, the technical features involved in the various embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0038] An implantable middle ear sensor calibration system provided by an embodiment of the present invention, asFigure 1 As shown, it includes an acoustic generating device, a sensor mounting device, an acoustic measuring device, a signal acquisition and analysis device, and a mounting device, where:

[0039] The acoustic generating device is used to generate the vibration signal required for calibrating the sensor. In this embodiment, the acoustic generating device includes an external controller and a speaker 4. The external controller is used to generate the required sound signal waveform, control its frequency and amplitude, so that it can conform to the characteristics of the input sound signal in the implanted state; the speaker 4 is connected to the external controller and is used to convert the transmitted sound signal into a vibration signal for output.

[0040] Specifically, the sound signal includes a swept-frequency sound signal, a single-frequency sound signal, and a voice sound signal. Among them, the swept-frequency sound signal and the single-frequency sound signal are preferably sine signals. By inputting the swept-frequency sound signal, the frequency response of the sensor within the human ear's audible frequency range can be obtained at one time; by inputting the single-frequency sound signal, the response and performance indicators of the sensor at a certain specific frequency can be obtained; by inputting the voice sound signal, the signal that the sensor can obtain in the real environment after implantation can be obtained, and the ability of the sensor to restore complex sound signals after actual implantation can be measured (the amplitude corresponds to the loudness of the sound signal, and the frequency corresponds to the pitch of the sound frequency), laying a foundation for subsequent implantation.

[0041] Furthermore, the surface of the diaphragm in the speaker 4 is circular and has a diameter of 10 mm to 50 mm. In addition, the audible frequency range of the speaker 4 satisfies the human ear's audible range (20 - 20000 Hz), and by adjusting the signal input through the acoustic sound generation platform, the output vibration amplitude can reach 7 nm, and there is still a reliable frequency resolution available at this amplitude.

[0042] The sensor mounting device is used to mount the implantable middle ear sensor to be calibrated on the acoustic generating device to simulate the state after being implanted into the ossicular chain. In this embodiment, the sensor mounting device includes a sensor mounting block 5, which is mounted on the diaphragm of the speaker 4. The sensor mounting block 5 simulates the mass and shape of the ossicle, ensuring that the sensor to be tested can be mounted on it for multiple mounting tests. The sensor should include a structure for mounting on the ossicular chain.

[0043] Furthermore, for the speaker 4, according to the characteristics of its hemispherical diaphragm, a circular sensor mounting block is made by 3D printing method, and the sensor mounting device is polished and cleaned to meet the requirements of multiple installation tests of the sensor. Specifically, by adjusting the shape of the sensor mounting block, it can be adjusted to the shapes of the three ossicles (malleus, incus, stapes) according to the implantation mounting points required in practice. Three different mounting blocks are made by 3D printing according to the scan model of the ossicles, and the selection of the implantation points is completed before implantation. The mounting position is polished and cleaned to meet the requirements of repeated installation of the sensor, enabling a single sensor to be calibrated at different implantation positions under the same experimental conditions, avoiding possible damage to the sensor due to the need to change the implantation position during the calibration process, and providing a reliable platform for the repeatability experiment of the sensor.

[0044] An acoustic measurement device is used to measure the amplitude, frequency and phase of the sound signal actually generated by the acoustic generating device, and import the data into the signal analysis system; the acoustic measurement device can be a vibration measurement device such as a laser displacement sensor, a Doppler vibrometer, etc. In this embodiment, the acoustic measurement device uses a laser displacement sensor 7 to measure the amplitude of the input vibration received when the sensor is fixed on the calibration system, ensuring that its amplitude conforms to the vibration amplitude data of the human ossicular chain measured in the experiment; the laser displacement sensor 7 preferably has a measurement range of up to 0.1 nm, and the sampling frequency can reach 20 kHz, and Keyence LK-H025 can be used.

[0045] A signal acquisition and analysis device is used to collect the signals of the acoustic measurement device and the sensor and analyze and compare them to obtain the performance of the sensor to be measured; the signal of the acoustic measurement device received is a displacement signal (i.e., the amplitude of the diaphragm / sensor to be measured at different sound signal frequencies), and the sensor signal is a voltage signal. In this embodiment, the signal acquisition and analysis device includes a voltage signal collector, a laser displacement sensor host computer and a signal processing unit. Among them, the voltage signal collector is used to collect the voltage signal output by the sensor to be measured and transmit it to the signal processing unit, and the model meets the requirement that the sampling rate can reach 200 kHz; the laser displacement sensor host computer is used to collect the displacement signal measured by the laser displacement sensor 7 for the diaphragm, transmit it to the signal processing unit, and meet the above sampling rate requirements; the signal processing unit is used to process the signals collected above.

[0046] Specifically, the signal processing unit includes: a vibration signal data preprocessing program that converts the input diaphragm displacement signal into an acceleration signal; a signal frequency-domain analysis program that performs frequency-domain analysis on the voltage signal input by the sensor to obtain the frequency-domain response and signal-to-noise ratio; a signal time-frequency analysis program that performs time-frequency analysis on the voltage signal input by the sensor to obtain the time-domain followability and frequency-domain resolution of the sensor for non-stationary signals (signals whose frequency changes with time), and obtains the dynamic frequency characteristics of the sensor; a signal normalization program that normalizes the sensor voltage signal after frequency-domain processing through the acceleration signal to obtain the ratio of the sensor voltage signal to the acceleration signal at each frequency, and obtains the sensor sensitivity data.

[0047] The installation device is used to reduce external interference, optimize the calibration performance of the overall system, and integrally fix and install other devices in the system. In this embodiment, the external installation device includes: an optical measurement platform 1, which serves as the overall installation base of the system and is provided with installation holes thereon to facilitate the installation of other structures; a speaker mounting block 3, which is used to mount and fix the speaker 4 and is connected to the optical measurement platform 1; a laser displacement sensor mounting block 6, which is used to fix the laser displacement sensor 7 and is connected to the optical measurement platform 1 to stabilize the distance to the speaker 4.

[0048] Specifically, the above-mentioned mounting blocks need to be designed according to the models of the selected speaker 4 and laser displacement sensor 7. Specifically, according to the positions of the mounting holes on the selected device model and the shape of the selected device, the design of the device installation part is completed. Furthermore, in order for the laser displacement sensor to operate correctly, according to the rated reference distance of the selected laser displacement sensor, the distance from the sensor installed on the speaker diaphragm to the laser emission port of the laser displacement sensor should be at the reference distance.

[0049] Furthermore, the sensor mounting block 5, the speaker mounting block 3, and the laser displacement sensor mounting block 6 are all made by 3D printing.

[0050] Specifically, the installation method of the above-mentioned calibration system is as follows:

[0051] First, complete the construction of the installation part of the laser sensor 7 and fix it on the optical measurement platform 1. Connect the laser displacement sensor 7 to its supporting laser displacement sensor host computer for preheating. Connect it to the computer host computer through the USB interface to collect its signals and verify that the laser displacement sensor 7 and its host computer are in good condition. After that, complete the installation of the acoustic generating device part. Install the fabricated speaker mounting block 3 on the optical measurement platform 1. Due to the characteristics of the selected speaker 4, there will be a short sound fluctuation when powering on. Therefore, the installation of the sensor needs to be carried out after the speaker 4 is powered on. Connect the sensor mounting block 5 to the speaker diaphragm with 498 glue, and then install the sensor on the sensor mounting block 5. The installation method mentioned here is the same as the installation method after the sensor is actually implanted, and this is used as a method to detect the installation performance of the sensor. After completing the installation of the sensor, install the speaker 4 on the speaker mounting block 3 and fix it. During this installation process, attention should be paid to the wires led out by the sensor to avoid damaging the sensor during installation.

[0052] The embodiment of the present invention also provides a calibration method for an implantable middle ear sensor, as Figure 2 shown, which includes the following steps:

[0053] The acoustic generating device generates a vibration signal, and the implantable middle ear sensor to be measured follows the vibration;

[0054] Collect the voltage signal and displacement signal of the implantable middle ear sensor;

[0055] Based on the voltage signal and displacement signal, realize the performance calibration of the implantable middle ear sensor.

[0056] The following uses a specific example to illustrate the calibration method in more detail:

[0057] First, connect the signal wires. Connect the wires on the sensor to the voltage signal collector (AD7606) and connect it to the computer host computer through the USB interface. At this time, start the initial calibration of the sensor. There are three purposes for this calibration: 1. Check whether the sensor works normally; 2. Detect whether the voltage signal collector (AD7606) works normally. 3. Measure the output signal of the sensor when the speaker does not receive a sound signal. The signal measured in point 3 is considered the initial signal of the sensor. By analysis, the background signal of the sensor under a pure experimental platform can be obtained, which serves as the basis for subsequent signal processing. This signal can also judge whether the sensor is affected by the electromagnetic radiation interference of the laser displacement sensor, so as to detect whether the electromagnetic shielding package on the sensor is in place. In addition, collect the signal of the laser displacement sensor to obtain the vibration amplitude information in the initial state of the sensor, and analyze it as a comparison with the above-mentioned sensor initial signal.

[0058] The sensor performance calibration officially begins. The responses of the sensor to three types of signals, namely swept-frequency sound signals, single-frequency sound signals, and voice sound signals, are calibrated:

[0059] 1. Swept-frequency sound signal. Specifically, the method is to output a swept-frequency signal from the matlab software in the computer host to the speaker to make it output swept-frequency vibration. The output swept-frequency signal has a swept frequency of 100 - 5000 Hz and a swept time of 15 seconds. In the host computer of the voltage signal collector, set the sampling frequency to 200 kHz and the sampling time to 20 seconds; in the host computer of the laser displacement sensor, set the sampling frequency to 20 kHz and the sampling time to 20 seconds. After starting the speaker to emit the sound signal, collect and save the two signals simultaneously. As Figure 3 shown, it presents the original waveform of the sensor output voltage signal obtained by this calibration method and the result after time-frequency analysis. The time-domain to frequency-domain response reducibility of the sensor can be determined based on this returned result.

[0060] 2. Single-frequency sound signal. Specifically, the method is to output a single-frequency signal from the matlab software in the computer host to the speaker to make it output single-frequency vibration. The output single-frequency signal ranges from 100 Hz to 5000 Hz, with measurements taken every 100 Hz, and the signal duration is 10 seconds. In the host computer of the voltage signal collector, set the sampling frequency to 200 kHz and the sampling time to 5 seconds; in the host computer of the laser displacement sensor, set the sampling frequency to 200 kHz and the sampling time to 5 seconds. After starting the speaker to emit the sound signal, collect and save the two signals simultaneously. As Figure 4 shown, it shows the frequency-domain analysis and time-frequency analysis of the sensor output voltage signal when the vibration signals input to the speaker are 1000, 2000, and 3000 Hz obtained by this calibration method. Based on this returned result, the amplitude of the voltage signal returned by the sensor at a specific frequency can be read out, and thus the sensitivity can be obtained by comparing it with the processed displacement signal (sensor - diaphragm vibration data).

[0061] 3. Voice sound signal. Specifically, the method is to output a signal from the sound playback software in the computer host to the speaker to make it output voice signal vibration. The duration of the output voice signal is the English sentence "the fire is very hot". In the host computer of the voltage signal collector, set the sampling frequency to 200 kHz and the sampling time to 10 seconds; in the host computer of the laser displacement sensor, set the sampling frequency to 20 kHz and the sampling time to 10 seconds. After starting the speaker to emit the sound signal, collect and save the two signals simultaneously. As Figure 5 shown, it presents the sensor output voltage signal obtained by this calibration method. The voice signal can be restored based on this returned result to judge the restoration degree of the sensor for voice signals.

[0062] After the computer host computer collects the voltage data output by the sensor and the displacement signal (sensor - diaphragm vibration data) collected by the laser displacement sensor, it starts to perform data analysis. Specifically, for the swept-frequency sound signal, the voltage signal is processed in the frequency domain, and the dynamic frequency characteristics of the sensor are obtained based on the voltage signal after frequency-domain processing. For the single-frequency sound signal, the displacement signal is converted into acceleration data by differentiation, and the obtained voltage data and acceleration data are subjected to Fourier transform spectrum analysis to obtain the voltage-frequency response of the sensor under the input of the swept-frequency signal, and compared with the acceleration-frequency response of the acceleration data. Through normalization, the sensor sensitivity parameter mV / g is obtained; through the voltage signal processed in the frequency domain, the signal-to-noise ratio parameter of the sensor at each single frequency can be obtained, which is used as an index to measure the quality of the sensor output signal. Through the voice sound signal, the response of the sensor under complex frequency input is obtained, and the performance index of the sensor in actual application after implantation is measured.

[0063] Those skilled in the art can easily understand that the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent replacements, and improvements made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A calibration system for an implantable middle ear sensor, characterized in that: It includes an acoustic generating device, a sensor mounting block, an acoustic measuring device and a signal acquisition and analysis device, wherein: The acoustic generating device is used to generate a vibration signal; The sensor mounting block is mounted on the acoustic generating device, and the sensor mounting block simulates the structure of the auditory ossicles and is used to mount the implantable middle ear sensor to be tested; The acoustic measurement device is used to measure the amplitude of the implanted middle ear sensor to obtain a displacement signal; The signal acquisition and analysis device is used to acquire the voltage signal of the implantable middle ear sensor and the displacement signal of the acoustic measurement device, and calibrate the performance of the implantable middle ear sensor based on the voltage signal and the displacement signal.

2. The calibration system for implantable middle ear sensor according to claim 1, characterized in that: The acoustic generating device comprises a loudspeaker, and the sensor mounting block is mounted on the diaphragm of the loudspeaker; and the acoustic measuring device is a laser displacement sensor.

3. The calibration system for implantable middle ear sensor according to claim 2, characterized in that: It also includes a mounting device, which includes an optical measurement platform and a speaker mounting block and a laser displacement sensor mounting block mounted on the optical measurement platform, wherein the speaker mounting block and the laser displacement sensor mounting block are used to mount a fixed speaker and a laser displacement sensor, respectively.

4. The calibration system for implantable middle ear sensor according to claim 3, characterized in that: The sensor mounting block, the loudspeaker mounting block and the laser displacement sensor mounting block are all made by a 3D printing method.

5. The calibration system for implantable middle ear sensor according to claim 2, characterized in that: The diaphragm surface of the loudspeaker is circular, and its diameter is 10 mm to 50 mm.

6. A calibration method based on the calibration system of the implantable middle ear sensor according to any one of claims 1 to 5, characterized in that: The steps include: The acoustic generating device generates a vibration signal, and the implantable middle ear sensor to be tested follows the vibration; Collecting voltage signals and displacement signals of implantable middle ear sensors; Based on the voltage signal and displacement signal, the performance calibration of the implantable middle ear sensor is achieved.

7. The calibration method according to claim 6, characterized in that: The acoustic generating device generates a vibration signal according to an input sound signal, and the sound signal is a swept frequency sound signal, a single frequency sound signal or a voice sound signal.

8. The calibration method according to claim 7, characterized in that: When the sound signal is a single-frequency sound signal, the performance calibration of the implantable middle ear sensor includes: Convert the displacement signal into an acceleration signal, and perform frequency domain processing on the voltage signal and the acceleration signal; The signal-to-noise ratio parameters of the implantable middle ear sensor at each single frequency are obtained based on the voltage signal after frequency domain processing; the voltage signal and acceleration signal after frequency domain processing are normalized to obtain the ratio of the voltage signal to the acceleration signal at different frequencies, thereby obtaining the sensitivity of the implantable middle ear sensor.

9. The calibration method according to claim 7, characterized in that: When the sound signal is a swept frequency sound signal, the performance calibration of the implantable middle ear sensor includes: performing frequency domain processing on the voltage signal, and obtaining the dynamic frequency characteristics of the implantable middle ear sensor based on the voltage signal after the frequency domain processing; When the sound signal is a speech sound signal, the performance calibration of the implantable middle ear sensor includes: obtaining the response of the implantable middle ear sensor under complex frequency input based on the voltage signal, and measuring the ability of the implantable middle ear sensor to restore complex sound signals after actual implantation.

10. The calibration method according to any one of claims 6 to 9, characterized in that: Before calibration, the amplitude of the sound signal at each frequency is adjusted in advance, including: The sound signal is converted into a vibration signal output by an acoustic generating device, and the implantable middle ear sensor to be tested follows the vibration; the amplitude of the implantable middle ear sensor is measured by an acoustic measuring device to obtain a displacement signal; the amplitude of the sound signal is adjusted to make the displacement signal consistent with the measured vibration displacement signal of the middle ear in the human body at the corresponding frequency.

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