Ultrasonic transducer chip, signal processing method and automotive ultrasonic radar device

Abstract

The embodiment of the application provides an ultrasonic transducer chip, a signal processing method and an automobile ultrasonic radar device, the ultrasonic transducer chip comprises: a sampling circuit, which is used for sampling an ultrasonic signal; a digital down conversion module, which is used for carrying out digital down conversion processing on the sampled signal; a low-pass filter, which is used for carrying out low-pass filtering on the mixed frequency signal; an amplitude calculation module, which is used for carrying out amplitude calculation according to the filtered signal; an envelope calibration module, which is used for carrying out calibration processing on the envelope amplitude curve, wherein the envelope calibration module calibrates the envelope amplitude curve at least between the transition period of the driving stage and the aftershock stage; and a threshold comparison circuit, which is used for comparing the final envelope curve with the envelope curve threshold. In the embodiment of the application, the envelope amplitude curve can be calibrated between the transition period of the driving stage and the aftershock stage, so that the system misjudgment caused by waveform fluctuation in the transition period can be avoided, and the accuracy of obstacle detection is improved.

Description

[0001] This application claims priority to Chinese Patent Application No. 202310375784.5, filed on April 10, 2023, entitled “A Signal Processing Circuit, Processing Method and Processing Chip for an Ultrasonic Transducer”, the entire contents of which are incorporated herein by reference. Technical Field

[0002] This application relates to the field of electronic technology, specifically to an ultrasonic transducer chip, a signal processing method, and an automotive ultrasonic radar device. Background Technology

[0003] Ultrasonic ranging, as a typical non-contact measurement method, is widely used in many scenarios, such as vehicle obstacle detection, industrial automation control, and construction engineering. Taking vehicle obstacle detection as an example, after emitting ultrasonic waves at frequencies of 20 kHz or higher (which are in the inaudible range), the ultrasonic transducer can sense the echo signal reflected from external obstacles and analyze the echo signal to determine the distance between the ultrasonic transducer and the obstacle, i.e., the detection distance. Based on this detection distance, corresponding prompts can be provided to the user (e.g., through a buzzer or by displaying the obstacle distance on a screen) to assist the user in safe driving.

[0004] Specifically, when distance detection is required, the main control circuit of the ultrasonic transducer chip receives a trigger signal from the host computer (such as an ECU) and controls the drive circuit to generate an ultrasonic drive signal. This drive signal is used to drive the ultrasonic transducer to emit ultrasonic waves (this process is called the "drive phase"). After the drive phase, the drive signal stops driving the ultrasonic transducer, but the ultrasonic transducer does not stop vibrating immediately. Instead, it generates periodic oscillation signals (this process is called the "aftershock phase"). During the aftershock phase, because the intensity of the oscillation signal is relatively large, the echo processing circuit cannot identify the echo signal (the signal reflected back by the emitted ultrasonic wave when it encounters an obstacle). After the aftershock phase, the echo processing circuit can identify the echo signal (this process is called the "receiving phase").

[0005] In the aforementioned signal processing, the drive signal during the driving phase, the oscillation signal during the aftershock phase, and the echo signal during the receiving phase are all input into the echo processing circuit for processing. However, the applicant has discovered that due to the phase difference or frequency difference between the drive signal and the oscillation signal, a strong waveform fluctuation occurs between the received drive signal and the oscillation signal. This waveform fluctuation causes fluctuations in the received signal, and in severe cases, it can lead to misjudgment of the detection distance.

[0006] It should be noted that the information disclosed in the background section of this application is intended only to enhance the understanding of the general background of this application, and should not be construed as an admission or in any way implying that the information constitutes prior art known to those skilled in the art. Summary of the Invention

[0007] In view of this, this application provides an ultrasonic transducer chip, a signal processing method, and an automotive ultrasonic radar device to solve the problem in the prior art where a phase difference or frequency difference between the drive signal and the oscillation signal leads to a strong waveform fluctuation between the received drive signal and the oscillation signal. This waveform fluctuation causes fluctuation in the received signal, and in severe cases, it can lead to misjudgment of the detection distance.

[0008] In a first aspect, embodiments of this application provide an ultrasonic transducer chip for electrical connection to an ultrasonic transducer. The chip receives signals in three phases: a driving phase, an aftershock phase, and a receiving phase. The chip includes:

[0009] A sampling circuit is electrically connected to the ultrasonic transducer to sample the ultrasonic signal and obtain a sampled signal.

[0010] A digital downconversion module, electrically connected to the sampling circuit, is used to receive the sampling signal output by the sampling circuit and perform digital downconversion processing on the sampling signal to obtain a mixed signal corresponding to the ultrasonic signal.

[0011] A low-pass filter, electrically connected to the digital down-conversion module, is used to receive the mixing signal output by the digital down-conversion module and perform low-pass filtering on the mixing signal to obtain a filtered signal.

[0012] An amplitude calculation module is electrically connected to the low-pass filter and is used to receive the filtered signal output by the low-pass filter, calculate the amplitude based on the filtered signal, and output an envelope amplitude curve.

[0013] An envelope calibration module, electrically connected to the amplitude calculation module, is used to receive the envelope amplitude curve output by the amplitude calculation module, and to calibrate the envelope amplitude curve to output a final envelope curve. The envelope calibration module calibrates the envelope amplitude curve at least during the transition period between the driving phase and the aftershock phase and outputs the final envelope curve for the transition period.

[0014] A threshold comparison circuit, electrically connected to the envelope calibration module, is used to receive the final envelope curve output by the envelope calibration module, compare the final envelope curve with the envelope curve threshold, and output the threshold comparison result.

[0015] Secondly, embodiments of this application provide an ultrasonic signal processing method applied to an ultrasonic transducer chip. The chip is used for electrical connection with an ultrasonic transducer. The chip receives signals in three stages: a driving stage, an aftershock stage, and a receiving stage. The method includes:

[0016] The ultrasonic signal is sampled to obtain the sampled signal;

[0017] The sampled signal is digitally down-converted to obtain a mixed signal corresponding to the ultrasonic signal;

[0018] The mixed signal is low-pass filtered to obtain a filtered signal;

[0019] The amplitude is calculated based on the filtered signal, and the envelope amplitude curve is output.

[0020] The envelope amplitude curve is calibrated and a final envelope curve is output, wherein the envelope amplitude curve is calibrated at least between the transition period of the driving phase and the aftershock phase and the final envelope curve of the transition period is output.

[0021] The final envelope curve is compared with the envelope curve threshold, and the threshold comparison result is output.

[0022] Thirdly, embodiments of this application provide an automotive ultrasonic radar device, comprising:

[0023] The chip described in the first aspect;

[0024] Ultrasonic transducer;

[0025] The chip and the ultrasonic transducer are electrically connected.

[0026] In this embodiment, the envelope amplitude curve can be calibrated between the transition period of the driving phase and the aftershock phase to avoid excessive waveform fluctuations during the transition period and system misjudgments that may be caused by fluctuations, thereby improving the accuracy of obstacle detection. Attached Figure Description

[0027] To more clearly illustrate the technical solutions of the embodiments of this application, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0028] Figure 1 This is a schematic diagram of an application scenario provided by an embodiment of this application;

[0029] Figure 2A and Figure 2BThis is a schematic diagram of the ranging principle of an ultrasonic system provided in an embodiment of this application;

[0030] Figure 3 A schematic diagram of the envelope amplitude curve before calibration is provided in an embodiment of this application;

[0031] Figure 4 This is a schematic diagram of the ranging principle of another ultrasonic system provided in an embodiment of this application;

[0032] Figure 5 This is a schematic diagram of the structure of an echo processing circuit provided in an embodiment of this application;

[0033] Figure 6 This is a schematic diagram of the ranging principle of another ultrasonic system provided in an embodiment of this application;

[0034] Figure 7 This is a schematic diagram of the ranging principle of another ultrasonic system provided in an embodiment of this application;

[0035] Figure 8 A threshold comparison diagram provided for an embodiment of this application;

[0036] Figure 9 A schematic diagram of the final calibrated envelope curve provided in an embodiment of this application;

[0037] Figure 10 This is a schematic diagram of the ranging principle of another ultrasonic system provided in an embodiment of this application;

[0038] Figure 11 This is a schematic diagram of the ranging principle of another ultrasonic system provided in an embodiment of this application;

[0039] Figure 12 A schematic flowchart of an ultrasonic signal processing method provided in an embodiment of this application;

[0040] Figure 13 This application also provides a schematic diagram of the structure of an automotive ultrasonic radar device. Detailed Implementation

[0041] To better understand the technical solution of this application, the embodiments of this application will be described in detail below with reference to the accompanying drawings.

[0042] It should be understood that the described embodiments are merely some, not all, of the embodiments in this application. All other embodiments obtained by those skilled in the art based on the embodiments in this application without inventive effort are within the scope of protection of this application.

[0043] The terminology used in the embodiments of this application is for the purpose of describing particular embodiments only and is not intended to be limiting of this application. The singular forms “a,” “the,” and “the” used in the embodiments of this application and the appended claims are also intended to include the plural forms unless the context clearly indicates otherwise.

[0044] It should be understood that the term "and / or" used in this article is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, or B existing alone. Additionally, the character " / " in this article generally indicates that the preceding and following related objects have an "or" relationship.

[0045] See Figure 1 This is a schematic diagram illustrating an application scenario provided by an embodiment of this application. Figure 1 The image shows a vehicle 100 and an obstacle 200. The rear of the vehicle 100 is equipped with multiple ultrasonic transducers 101. When the user (or in the case of autonomous driving) controls the vehicle 100 to reverse (or in any scenario such as parallel parking or obstacle recognition), the ultrasonic transducers 101 can emit ultrasonic waves and receive echo signals. (The ultrasonic transducer can be two independent devices including an ultrasonic emitting transducer and an ultrasonic receiving transducer, or it can be a single device that can both emit and receive ultrasonic waves.) The distance between the ultrasonic transducers 101 (i.e., the vehicle 100) and the obstacle 200 can be calculated, and corresponding prompts can be provided to the user (e.g., a warning sound is output through a buzzer or the distance to the obstacle is displayed on a screen) to assist the user in driving safely.

[0046] It should be pointed out that, Figure 1 The examples provided in this application are merely one possible application scenario and should not be construed as limiting the scope of protection of this application. For instance, ultrasonic ranging, in addition to its application in vehicle obstacle detection, may also be applied in industrial automatic control, construction engineering surveying, and other scenarios. In other application scenarios, the obstacle may also be referred to as the "object to be detected." Besides being located at the rear of the vehicle, ultrasonic transducers can also be located at the side or front of the vehicle to detect obstacles on the side or front of the vehicle. Furthermore, in addition to four ultrasonic transducers, more or fewer ultrasonic transducers can be used, etc. This application does not impose specific limitations in these respects.

[0047] See Figure 2A and Figure 2B This is a schematic diagram illustrating the ranging principle of an ultrasonic system provided in an embodiment of this application. Figure 2A and Figure 2BAs shown, the ultrasonic system includes an Electronic Control Unit (ECU), an ultrasonic transducer chip, and an ultrasonic transducer. The ultrasonic transducer chip includes a main control circuit, a drive circuit, and an echo processing circuit. The ECU and the main control circuit are communicatively connected. The output of the main control circuit is electrically connected to the input of the drive circuit, the output of the drive circuit is electrically connected to the input of the ultrasonic transducer, the output of the ultrasonic transducer is electrically connected to the input of the echo processing circuit, and the output of the echo processing circuit is electrically connected to the input of the main control circuit.

[0048] Specifically, in Figure 2A In the ultrasonic system shown, the input and output terminals of the ultrasonic transducer are respectively set. For example... Figure 2A As shown, the two ports below the ultrasonic transducer are electrically connected to the output of the drive circuit as input terminals, and the two ports above the ultrasonic transducer are electrically connected to the input of the echo processing circuit as output terminals. Figure 2B In the ultrasonic system shown, the same set of ports serves as both the input and output terminals of the ultrasonic transducer. For example... Figure 2B As shown, the two ports at the bottom of the ultrasonic transducer can be used as input terminals to be electrically connected to the output terminals of the drive circuit, and simultaneously as output terminals to be electrically connected to the input terminals of the echo processing circuit. It should be noted that... Figure 2A and Figure 2B The inclusion of two ports at the input and / or output of the ultrasonic transducer is merely an illustrative example; it can also be configured with more or fewer ports. Furthermore, in different implementations, there are other variations in the functional units and / or connections between functional units of the ultrasonic system, as described in other parts of this application.

[0049] When distance detection is required, the main control circuit of the ultrasonic transducer chip receives a trigger signal from the ECU and controls the drive circuit to generate an ultrasonic drive signal. This drive signal drives the ultrasonic transducer to emit ultrasonic waves (this process is called the "drive phase"). After the drive phase, the drive signal stops driving the ultrasonic transducer, but the ultrasonic transducer does not stop vibrating immediately. Instead, it generates periodic oscillation signals (this process is called the "aftershock phase"). During the aftershock phase, because the intensity of the oscillation signal is relatively large, the echo processing circuit cannot identify the echo signal (the signal reflected back by the emitted ultrasonic wave when it encounters an obstacle). After the aftershock phase, the echo processing circuit can identify the echo signal (this process is called the "receive phase").

[0050] In the aforementioned signal processing, the drive signal during the driving phase, the oscillation signal during the aftershock phase, and the echo signal during the receiving phase are all input to the echo processing circuit for processing. Particularly in cases where an ultrasonic transducer acts as both a drive and a receiver, the drive signal during the driving phase is directly input to the echo processing circuit, along with the oscillation and echo signals from the ultrasonic transducer. Upon receiving the ultrasonic signal, the echo processing circuit extracts the envelope amplitude curve of the ultrasonic signal. Further, it compares the envelope amplitude curve with a preset envelope threshold to obtain a threshold comparison result. Based on the threshold comparison result, it can determine whether an obstacle has been detected and the distance to the obstacle. Specifically, the threshold comparison result may include a first logic and a second logic. For example, the first logic is 1 and the second logic is 0; or, the first logic is 0 and the second logic is 1. In other parts of this document, logic "1" may also be referred to as a high level, and logic "0" may also be referred to as a low level.

[0051] Typically, the amplitude of the envelope amplitude curves during the driving and oscillation phases is very large, exceeding the maximum input range of the sampling circuit. This is reflected in the envelope amplitude curve waveform as clipped peaks during the driving and oscillation phases. However, in practical applications, a phase difference or frequency difference between the driving and oscillation signals may cause a strong waveform fluctuation between the received driving and oscillation signals. This waveform fluctuation can lead to misjudgments of the detection distance.

[0052] For example, in Figure 3 The diagram illustrates an envelope amplitude curve comprising a driving phase, an aftershock phase, and a receiving phase. During the driving and aftershock phases, the envelope amplitude curve is clipped. However, between the driving and aftershock phases, there is a significant dip in the envelope amplitude curve. This dip can cause large signal fluctuations, and if the dip falls below the envelope curve threshold, it may lead to misjudgments of the detection distance.

[0053] Specifically, as mentioned above, whether an obstacle has been detected can be determined by comparing the envelope amplitude curve and the envelope curve threshold. Figure 3 In the application scenario shown, when the envelope amplitude curve is less than the envelope curve threshold, the threshold comparison result is high; when the envelope amplitude curve is greater than the envelope curve threshold, the threshold comparison result is low. Therefore, the first low level is detected between t1 and t2, the second low level is detected between t3 and t4, and the third low level is detected between t5 and t6.

[0054] It is understandable that the third low-level signal corresponds to the low-level signal of the echo signal. Therefore, the detection of an obstacle and its distance can be determined through the third low-level signal. Furthermore, since the first low-level signal is detected during the drive phase, a feasible solution is for the system to directly ignore it. However, the second low-level signal could lead to a misjudgment; the system might mistakenly interpret it as the low-level signal corresponding to the echo signal and then determine the obstacle distance based on it. Clearly, this judgment is incorrect, and the second low-level signal is caused by the dip between the drive phase and the aftershock phase.

[0055] To address the aforementioned issues, this application provides an ultrasonic transducer chip that can calibrate the envelope amplitude curve during the transition period between the driving and aftershock phases. This avoids excessive waveform fluctuations during the transition period and prevents potential system misjudgments caused by such fluctuations, thereby improving the accuracy of obstacle detection. The specific implementation will be described in detail below.

[0056] See Figure 4 This is a schematic diagram illustrating the ranging principle of another ultrasonic system provided in an embodiment of this application. Figure 4 As shown, in Figure 2A Based on the ultrasonic system shown, the echo processing circuit in the ultrasonic transducer chip further includes a sampling circuit, a digital down-conversion module, a low-pass filter, an amplitude calculation module, and an envelope calibration module; the main control circuit further includes a threshold comparison circuit. It should be noted that the ultrasonic transducer chip described in this application embodiment can also be applied to… Figure 2B The ultrasonic system shown is, for the sake of brevity, referred to only as [missing information] in this article. Figure 2A The ultrasonic system shown is used as an example for explanation.

[0057] Please continue reading. Figure 4 The input terminal of the sampling circuit is electrically connected to the output terminal of the ultrasonic transducer. The output terminal of the sampling circuit is electrically connected to the input terminal of the digital down-conversion module. The output terminal of the digital down-conversion module is electrically connected to the input terminal of the low-pass filter. The output terminal of the low-pass filter is electrically connected to the input terminal of the amplitude calculation module. The output terminal of the amplitude calculation module is electrically connected to the input terminal of the envelope calibration module. The output terminal of the envelope calibration module is electrically connected to the input terminal of the threshold comparison circuit.

[0058] The sampling circuit is used to sample the received ultrasonic signal to obtain a sampled signal. As mentioned above, the drive signal in the driving phase, the oscillation signal in the aftershock phase, and the echo signal in the receiving phase are all input into the echo processing circuit for processing. Therefore, the sampled signal includes the drive signal in the driving phase, the oscillation signal in the aftershock phase, and the echo signal in the receiving phase.

[0059] In one possible implementation, to reproduce the received ultrasonic signal as accurately as possible, the sampling frequency of the sampling circuit can be increased. Specifically, the sampling frequency of the sampling circuit is greater than the oscillation frequency of the ultrasonic signal itself. For example, if the driving circuit emits an ultrasonic signal at a frequency of f0, the sampling circuit samples the ultrasonic signal at a sampling frequency of n*f0, where n>1. For example, n can be 4, 8, etc.

[0060] In a specific implementation, the sampling circuit can be an analog-to-digital converter (ADC). Of course, those skilled in the art can set other types of sampling circuits according to actual needs, and the embodiments of this application do not impose specific limitations on this.

[0061] The digital down-conversion module receives the sampled signal output from the sampling circuit and performs digital down-conversion processing on the sampled signal to obtain a mixed signal corresponding to the ultrasonic signal. Specifically, the sampled signal can be digitally down-converted based on the local signal to obtain the corresponding mixed signal, which includes high-frequency and low-frequency signals. The low-frequency signal is the desired signal; therefore, in subsequent steps, the high-frequency signal needs to be filtered out to obtain the desired low-frequency signal. Furthermore, in practical applications, since ultrasonic signals are usually complex signals, it is necessary to perform digital down-conversion processing on the sampled signal based on two mutually orthogonal local signals to obtain two mixed signals.

[0062] See Figure 5 This is a schematic diagram of an echo processing circuit provided in an embodiment of this application. Figure 5 As shown in the embodiment of this application, the digital down-conversion module specifically includes a first frequency conversion module and a second frequency conversion module. The first and second frequency conversion modules are electrically connected to the sampling circuit and are used to receive the sampling signal output by the sampling circuit. Specifically, the first frequency conversion module performs digital down-conversion processing on the sampling signal based on the local signal sin(2πfot) to obtain a first mixed signal; the second frequency conversion module performs digital down-conversion processing on the sampling signal based on the local signal cos(2πfot) to obtain a second mixed signal. It can be understood that the local signals sin(2πfot) and cos(2πfot) are orthogonal to each other; that is, the first and second frequency conversion modules perform digital down-conversion processing on the sampling signal based on mutually orthogonal local signals.

[0063] Furthermore, the ultrasonic transducer chip also includes a storage unit where the aforementioned local signals can be stored. Specifically, the storage unit is electrically connected to the digital down-conversion module, which can directly retrieve the local signals from the storage unit, such as... Figure 6As shown. Alternatively, the storage unit is electrically connected to the main control circuit. When the digital down-converter module needs a local signal, the main control circuit can obtain the local signal from the storage unit and then forward the local signal to the digital down-converter module, such as... Figure 7 As shown.

[0064] In specific implementations, the storage unit can be any form of storage unit or element, such as RAM (random access memory), ROM (read-only memory), register, or cache.

[0065] A low-pass filter is used to receive the mixing signal output from the digital down-converter module and perform low-pass filtering on the mixing signal to obtain a filtered signal. It can be understood that when the digital down-converter module outputs two mixing signals, it should correspondingly include two low-pass filters.

[0066] Please continue reading. Figure 5 In this embodiment, the low-pass filter specifically includes a first low-pass filter and a second low-pass filter. The first low-pass filter is electrically connected to the first frequency converter module and is used to receive the first mixing signal output by the first frequency converter module, and to perform low-pass filtering on the first mixing signal to obtain a first filtered signal, i.e., the low-frequency signal in the first mixing signal. The second low-pass filter is electrically connected to the second frequency converter module and is used to receive the second mixing signal output by the second frequency converter module, and to perform low-pass filtering on the second mixing signal to obtain a second filtered signal, i.e., the low-frequency signal in the second mixing signal.

[0067] The amplitude calculation module receives the filtered signal output from the low-pass filter, calculates the amplitude based on the filtered signal, and outputs the envelope amplitude curve. In other words, when the low-pass filter outputs two filtered signals, the amplitude can be calculated based on these two signals.

[0068] Please continue reading. Figure 5 In this embodiment, the amplitude calculation module is electrically connected to the first low-pass filter and the second low-pass filter respectively (the electrical connection can be a direct electrical connection or an indirect electrical connection through the downsampling module, which will be described below), and is used to receive the first filtered signal and the second filtered signal output by the first low-pass filter and the second low-pass filter respectively, and to perform amplitude calculation based on the first filtered signal and the second filtered signal to obtain the envelope amplitude curve.

[0069] In practical implementation, it can be based on the formula: The envelope amplitude curve is calculated. Here, P is the amplitude of the envelope amplitude curve, I is the amplitude of the first filtered signal, and Q is the amplitude of the second filtered signal. It should be noted that when the echo signal processing circuit includes a downsampling module, I is the amplitude of the first downsampled signal, and Q is the amplitude of the second downsampled signal.

[0070] The envelope calibration module receives the envelope amplitude curve output by the amplitude calculation module, calibrates the envelope amplitude curve, and outputs the final envelope curve. (As mentioned above...) Figure 3 As described in the description, the misjudgment of the detection distance is mainly caused by waveform fluctuations during the transition period between the driving phase and the aftershock phase. Therefore, the envelope calibration module calibrates the envelope amplitude curve at least during the transition period between the driving phase and the aftershock phase and outputs the final envelope curve for the transition period. Specifically, the start point of the transition period is located at the end point of the driving phase, and the end point of the transition period is the point corresponding to a specified time or a specified number of cycles after the end point of the driving phase. Typically, this specified time or specified number of cycles is related to the duration of the aftershock phase, and its specific value can be determined based on experience or through testing.

[0071] Furthermore, outside the transition period, since the envelope amplitude curve does not exhibit drastic waveform fluctuations, the envelope calibration module can directly output the envelope amplitude curve to form the final envelope curve. Of course, outside the transition period, the envelope calibration module can also calibrate the envelope amplitude curve to obtain the final envelope curve; this embodiment does not impose specific limitations on this.

[0072] Please continue reading. Figure 3 In this embodiment, the envelope amplitude curve between the transition period of the driving phase and the aftershock phase exhibits a significant dip, causing strong waveform fluctuations and potentially leading to misjudgments of the detection distance by the system. Therefore, the envelope calibration module needs to focus on calibrating this dip. Further analysis reveals that the difference between this dip and other locations (during the driving phase and the early aftershock phase) lies in the smaller amplitude of the envelope amplitude curve. Therefore, the need for envelope amplitude curve calibration can be determined based on its amplitude.

[0073] Specifically, a first amplitude threshold can be set, and the amplitude of the envelope amplitude curve can be compared. If the amplitude of the envelope amplitude curve is less than the preset first amplitude threshold, the envelope amplitude curve is calibrated; if the amplitude of the envelope amplitude curve is greater than the preset first amplitude threshold, the envelope amplitude curve is not calibrated.

[0074] Furthermore, to make the final envelope curve after calibration smoother, a second amplitude threshold can be set based on the first amplitude threshold, wherein the first amplitude threshold is greater than the second amplitude threshold. If the amplitude of the envelope amplitude curve is less than the preset first amplitude threshold but greater than or equal to the second amplitude threshold, the first calibration offset strategy is used to calibrate the envelope amplitude curve; if the amplitude of the envelope amplitude curve is less than the second amplitude threshold, the second calibration offset strategy is used to calibrate the envelope amplitude curve.

[0075] In one possible implementation, the first amplitude threshold is the maximum amplitude of the envelope amplitude curve, and / or the second amplitude threshold is half of the maximum amplitude of the envelope amplitude curve. Of course, those skilled in the art can adaptively adjust the first amplitude threshold and / or the second amplitude threshold according to actual needs, and the embodiments of this application do not impose specific limitations in this regard.

[0076] In specific implementation, the first calibration offset strategy is: P_final = (P_ev + P_cal1) / 2, and the second calibration offset strategy is: P_final = (P_ev + P_cal2) / 2. Where P_final is the amplitude of the final envelope curve output by the envelope calibration module, P_ev is the amplitude of the envelope amplitude curve output by the amplitude calculation module, P_cal1 is the first calibration factor, and P_cal2 is the second calibration factor. For example, the first calibration factor is 1.25 * P_max, and the second calibration factor is 1.5 * P_max; where P_max is the maximum amplitude of the envelope amplitude curve. Of course, those skilled in the art can adjust the specific values ​​of the first and second calibration factors according to actual needs, but it should be ensured that the first calibration factor is less than the second calibration factor to make the final envelope curve after calibration smoother.

[0077] Please continue reading. Figure 4 In this embodiment, the main control circuit further includes a threshold comparison circuit. This threshold comparison circuit receives the final envelope curve output by the envelope calibration module and compares the final envelope curve with the envelope curve threshold, outputting a threshold comparison result. Specifically, the threshold comparison result may include a first logic and a second logic. For example, the first logic is 1 and the second logic is 0; or, the first logic is 0 and the second logic is 1. In other parts of this document, logic "1" may also be referred to as a high level, and logic "0" may also be referred to as a low level.

[0078] See Figure 8 This is a schematic diagram illustrating a threshold comparison provided in an embodiment of this application. Figure 8As shown, the envelope value of the final envelope curve and the envelope curve threshold are simultaneously input into the threshold comparison circuit. By comparing the magnitudes of the final envelope curve and the envelope curve threshold, a high or low level signal is output. In this embodiment, when a low level appears in the threshold comparison result, it is determined that an obstacle has been detected. Of course, the judgment logic in the threshold comparison circuit can also be adjusted so that a high level appears in the threshold comparison result, indicating that an obstacle has been detected. This embodiment does not impose specific limitations on this.

[0079] See Figure 9 This is a schematic diagram of the final calibrated envelope curve provided in an embodiment of this application. (Comparison) Figure 3 and Figure 9 It can be seen that after the calibration process of the envelope calibration module, the concave area between the driving phase and the aftershock phase tends to be gentle. The amplitude at the concave area is higher than the threshold of the envelope curve, so it will not cause misjudgment of the detection distance. The concave area here is smoother and has been well processed.

[0080] Specifically, when the envelope amplitude curve is less than the envelope curve threshold, the threshold comparison result is low; when the envelope amplitude curve is greater than the envelope curve threshold, the threshold comparison result is high. Therefore, the first low level is detected between t1 and t4, and the second low level is detected between t5 and t6. Since the first low level is detected during the driving phase, the system can directly ignore this low-level signal. It can be understood that the second low level is the low-level signal corresponding to the echo signal; therefore, the detection of an obstacle and its distance can be determined through the second low-level signal.

[0081] In summary, the ultrasonic transducer chip provided in this application embodiment can calibrate the envelope amplitude curve during the transition period between the driving phase and the aftershock phase, so as to avoid system misjudgment caused by waveform fluctuations during the transition period and improve the accuracy of obstacle detection.

[0082] As mentioned above, oversampling can be performed to reproduce the received ultrasonic signal as accurately as possible, whereby the sampling frequency of the sampling circuit is greater than the oscillation frequency of the ultrasonic signal itself. However, oversampling results in a larger amount of data, which, while improving the reproduction of the ultrasonic signal, increases the data processing load of subsequent circuits, leading to a decrease in system response speed and an increase in system power consumption.

[0083] See Figure 10 This is a schematic diagram illustrating the ranging principle of another ultrasonic system provided in an embodiment of this application. Figure 10 As shown, the embodiments of this application are in Figure 4Based on the ultrasonic system shown, a downsampling module is further provided between the low-pass filter and the amplitude calculation module. Specifically, the input terminal of the downsampling module is electrically connected to the output terminal of the low-pass filter, used to receive the filtered signal output by the low-pass filter and downsample the filtered signal to obtain a downsampled signal; the output terminal of the downsampling module is electrically connected to the input terminal of the amplitude calculation module, used to output the downsampled signal to the amplitude calculation module, so that the amplitude calculation module can perform amplitude calculation based on the downsampled signal and output the envelope amplitude curve. This embodiment of the application, while restoring the received ultrasonic signal as accurately as possible, can also reduce the amount of data processing, thus achieving the effect of balancing improved detection accuracy and reduced data processing volume.

[0084] In one possible implementation, when the sampling frequency of the sampling circuit is n*f0, the sampling frequency of the downsampling module is also f0, meaning that one point is sampled every n points as the downsampled signal. In general, the ultrasonic transducer emits ultrasonic signals at a frequency of f0, the sampling circuit samples at a frequency of n*f0, and the downsampling module downsamples at a frequency of f0. It can be understood that the downsampling module and the ultrasonic transducer have the same frequency. This configuration reduces circuit complexity.

[0085] It is understandable that when a low-pass filter outputs two filtered signals, it should correspondingly include two downsampling modules.

[0086] Please continue reading. Figure 5 In this embodiment, the downsampling module specifically includes a first downsampling module and a second downsampling module. The input of the first downsampling module is electrically connected to the output of a first low-pass filter, and it receives the first filtered signal output by the first low-pass filter and downsamples the first filtered signal to obtain a first downsampled signal. The input of the second downsampling module is electrically connected to the output of a second low-pass filter, and it receives the second filtered signal output by the second low-pass filter and downsamples the second filtered signal to obtain a second downsampled signal. An amplitude calculation module is electrically connected to both the first and second downsampling modules, and it receives the first downsampled signal output by the first downsampling module and the second downsampled signal output by the second downsampling module, calculates the amplitude based on the first and second downsampled signals, and outputs an envelope amplitude curve.

[0087] See Figure 11 This is a schematic diagram illustrating the ranging principle of another ultrasonic system provided in an embodiment of this application. Figure 11 As shown, the embodiments of this application are in Figure 4Based on the ultrasonic system shown, a preamplifier circuit is also provided between the sampling circuit and the ultrasonic transducer. The input terminal of the preamplifier circuit is electrically connected to the output terminal of the ultrasonic transducer, and the output terminal of the preamplifier circuit is electrically connected to the input terminal of the sampling circuit. Specifically, the preamplifier circuit may include an amplifier and a filter. The amplifier amplifies the received ultrasonic signal, and the filter filters the received ultrasonic signal to obtain an ultrasonic signal of a specified frequency. This filtering can be high-pass, low-pass, or band-pass filtering. It should be noted that those skilled in the art can add or remove functions from the preamplifier circuit according to actual needs; or the preamplifier circuit can be deleted. This application embodiment does not impose specific limitations in this regard.

[0088] Furthermore, in some applications, the voltage of the drive signal output by the drive circuit is too low, which may prevent the ultrasonic transducer from emitting ultrasonic waves, or the low drive voltage or current may result in a short obstacle detection distance. Therefore, a transformer is installed between the output of the drive circuit and the input of the ultrasonic transducer. The transformer increases the voltage / current of the drive signal, thereby driving the ultrasonic transducer to emit ultrasonic waves. It should be noted that the echo signal received by the ultrasonic transducer can be directly transmitted to the echo processing circuit through the output without going through the transformer.

[0089] It should be noted that the ultrasonic transducer shown in the above embodiments can be two independent devices including an ultrasonic transmitting transducer and an ultrasonic receiving transducer, or it can be a device that simultaneously transmits and receives ultrasonic waves; in addition, the ECU can also be other microprocessor units with data processing capabilities, and this application embodiment does not impose specific limitations on this.

[0090] Corresponding to the above embodiments, this application also provides an ultrasonic signal processing method, which can be applied to the ultrasonic transducer chip described in the above embodiments, wherein the ultrasonic transducer chip is used for electrical connection with the ultrasonic transducer.

[0091] See Figure 12 This is a flowchart illustrating an ultrasonic signal processing method provided in an embodiment of this application. Figure 12 As shown, it mainly includes the following steps.

[0092] Step S1201: Sample the ultrasonic signal to obtain a sampled signal;

[0093] Step S1202: Perform digital down-conversion processing on the sampled signal to obtain a mixed signal corresponding to the ultrasonic signal;

[0094] Step S1203: Perform low-pass filtering on the mixing signal to obtain the filtered signal;

[0095] Step S1204: Calculate the amplitude based on the filtered signal and output the envelope amplitude curve;

[0096] Step S1205: The envelope amplitude curve is calibrated and the final envelope curve is output. The envelope amplitude curve is calibrated at least during the transition period between the driving phase and the aftershock phase, and the final envelope curve for the transition period is output.

[0097] Step S1206: Compare the final envelope curve with the envelope curve threshold and output the threshold comparison result.

[0098] In one possible implementation, step S1205 specifically includes: comparing the magnitude of the envelope amplitude curve; if the magnitude of the envelope amplitude curve is less than a preset first amplitude threshold, then calibrating the envelope amplitude curve.

[0099] In one possible implementation, the step of calibrating the envelope amplitude curve if its amplitude is less than a preset first amplitude threshold specifically includes: if the amplitude of the envelope amplitude curve is less than the preset first amplitude threshold but greater than or equal to a second amplitude threshold, then calibrating the envelope amplitude curve using a first calibration offset strategy; if the amplitude of the envelope amplitude curve is less than the second amplitude threshold, then calibrating the envelope amplitude curve using a second calibration offset strategy; wherein the first amplitude threshold is greater than the second amplitude threshold.

[0100] In one possible implementation, the first amplitude threshold is the maximum amplitude value of the envelope amplitude curve, and / or the second amplitude threshold is half of the maximum amplitude value of the envelope amplitude curve.

[0101] In one possible implementation, the first calibration offset strategy is: P_final = (P_ev + P_cal1) / 2, and the second calibration offset strategy is: P_final = (P_ev + P_cal2) / 2; where P_final is the magnitude of the final envelope curve, P_ev is the magnitude of the envelope amplitude curve, P_cal1 is the first calibration factor, and P_cal2 is the second calibration factor.

[0102] In one possible implementation, the first calibration factor is 1.25*P_max, and the second calibration factor is 1.5*P_max; where P_max is the maximum amplitude of the envelope amplitude curve.

[0103] In one possible implementation, the start point of the transition period is located at the end point of the driving phase, and the end point of the transition period is a specified time or a point corresponding to a specified number of cycles after the end point of the driving phase.

[0104] In one possible implementation, outside the transition period, the envelope amplitude curve is directly output to form the final envelope curve.

[0105] In one possible implementation, the ultrasonic transducer is driven to emit an ultrasonic signal at a frequency of f0, and the ultrasonic signal is sampled at a sampling frequency of n*f0 to obtain a sampled signal, where n>1.

[0106] In one possible implementation, after obtaining the filtered signal, the filtered signal is first downsampled to obtain a downsampled signal; then, the amplitude is calculated based on the downsampled signal, and the envelope amplitude curve is output.

[0107] In one possible implementation, the step of performing digital down-conversion processing on the sampled signal to obtain a mixed signal corresponding to the ultrasonic signal includes: converting the sampled signal into a first mixed signal and a second mixed signal using mutually orthogonal local signals respectively; the step of performing low-pass filtering on the mixed signal to obtain a filtered signal includes: performing low-pass filtering on the first mixed signal and the second mixed signal respectively to obtain a first filtered signal and a second filtered signal; the step of downsampling the filtered signal to obtain a downsampled signal includes: downsampling the first filtered signal and the second filtered signal respectively to obtain a first downsampled signal and a second downsampled signal; the step of calculating the amplitude based on the downsampled signal and outputting an envelope amplitude curve includes: calculating the amplitude based on the first downsampled signal and the second downsampled signal and outputting the envelope amplitude curve.

[0108] It should be noted that the specific content involved in the embodiments of this application can be found in the description of the above embodiments, and will not be repeated here for the sake of brevity.

[0109] Corresponding to the above embodiments, this application also provides an automotive ultrasonic radar device.

[0110] See Figure 13 This is a schematic diagram of the structure of an automotive ultrasonic radar device provided in an embodiment of this application. Figure 13 As shown, the automotive ultrasonic radar device includes an ultrasonic transducer chip and an ultrasonic transducer, wherein the ultrasonic transducer chip and the ultrasonic transducer are electrically connected.

[0111] It should be noted that the specific details of the ultrasonic transducer chip and ultrasonic transducer involved in the embodiments of this application can be found in the description of the above embodiments, and will not be repeated here for the sake of brevity.

[0112] Corresponding to the above embodiments, this application also provides a computer-readable storage medium, wherein the computer-readable storage medium may store a program, wherein when the program runs, it can control the device where the computer-readable storage medium is located to execute some or all of the steps in the above method embodiments. Specifically, the computer-readable storage medium may be a magnetic disk, an optical disk, read-only memory (ROM), or random access memory (RAM), etc.

[0113] Corresponding to the above embodiments, this application also provides a computer program product containing executable instructions that, when executed on a computer, cause the computer to perform some or all of the steps in the above method embodiments.

[0114] In this application embodiment, "at least one" refers to one or more, and "more than one" refers to two or more. "And / or" describes the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent the existence of A alone, the simultaneous existence of A and B, or the existence of B alone. A and B can be singular or plural. The character " / " generally indicates that the preceding and following related objects are in an "or" relationship. "At least one of the following" and similar expressions refer to any combination of these items, including any combination of single or plural items. For example, at least one of a, b, and c can represent: a, b, c, ab, ac, bc, or abc, where a, b, and c can be single or multiple.

[0115] Those skilled in the art will recognize that the units and algorithm steps described in the embodiments disclosed herein can be implemented using electronic hardware, computer software, or a combination of electronic hardware and software. Whether these functions are implemented in hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of this application.

[0116] Those skilled in the art will understand that, for the sake of convenience and brevity, the specific working processes of the systems, devices, and units described above can be referred to the corresponding processes in the foregoing method embodiments, and will not be repeated here.

[0117] In the several embodiments provided in this application, any function, if implemented as a software functional unit and sold or used as an independent product, can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of this application, in essence, or the part that contributes to the prior art, or a part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of this application. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.

[0118] The above description is merely a specific embodiment of this application. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the protection scope of this application. The protection scope of this application should be determined by the protection scope of the claims.

Claims

1. An ultrasonic transducer chip for electrical connection with an ultrasonic transducer, the chip receiving signals divided into a drive phase, an aftershock phase and a receive phase, characterised in that, The chip comprises: a sampling circuit for sampling an ultrasonic signal to obtain a sampling signal; a digital down-conversion module electrically connected to the sampling circuit, configured to receive the sampling signal output by the sampling circuit and perform digital down-conversion processing on the sampling signal to obtain a mixed signal corresponding to the ultrasonic signal; a low-pass filter electrically connected to the digital down-conversion module, configured to receive the mixed signal output by the digital down-conversion module and perform low-pass filtering on the mixed signal to obtain a filtered signal; an amplitude calculation module electrically connected to the low-pass filter, configured to receive the filtered signal output by the low-pass filter and perform amplitude calculation on the filtered signal to output an envelope amplitude curve; an envelope calibration module electrically connected to the amplitude calculation module, configured to receive the envelope amplitude curve output by the amplitude calculation module and perform calibration processing on the envelope amplitude curve to output a final envelope curve, wherein the envelope calibration module calibrates the envelope amplitude curve and outputs a final envelope curve of a transition period between the driving phase and the aftershock phase. The envelope calibration module is specifically configured to:

2. The chip according to claim 1, characterized in that, compare the amplitude of the envelope amplitude curve, and if the amplitude of the envelope amplitude curve is less than a preset first amplitude threshold, calibrate the envelope amplitude curve. The envelope calibration module is specifically configured to:

3. The chip of claim 2, wherein, if the amplitude of the envelope amplitude curve is less than the preset first amplitude threshold and greater than or equal to a second amplitude threshold, adopt a first calibration offset strategy to calibrate the envelope amplitude curve; if the amplitude of the envelope amplitude curve is less than the second amplitude threshold, adopt a second calibration offset strategy to calibrate the envelope amplitude curve. The first amplitude threshold is greater than the second amplitude threshold. The first amplitude threshold is the maximum amplitude of the envelope amplitude curve, and / or the second amplitude threshold is half of the maximum amplitude of the envelope amplitude curve.

4. The chip of claim 3, wherein The first calibration offset strategy is P_final=(P_ev+P_cal1) / 2, and the second calibration offset strategy is P_final=(P_ev+P_cal2) / 2; 5. The chip of claim 4, wherein, wherein P_final is the amplitude of the final envelope curve output by the envelope calibration module, P_ev is the amplitude of the envelope amplitude curve output by the amplitude calculation module, P_cal1 is a first calibration factor, and P_cal2 is a second calibration factor. The first calibration factor is 1.25*P_max, and the second calibration factor is 1.5*P_max; 6. The chip of claim 5, wherein, wherein P_max is the maximum amplitude of the envelope amplitude curve. ​ 7. The chip of claim 1, wherein The starting point of the transition period is located at the ending point of the driving phase, and the ending point of the transition period is a point corresponding to a specified time or a specified number of cycles after the ending point of the driving phase.

8. The chip of claim 1, wherein, During the transition period, the envelope amplitude curve is directly outputted by the envelope calibration module to form the final envelope curve.

9. The chip according to any one of claims 1 to 8, wherein Further comprising a driving circuit electrically connected with the ultrasonic transducer to drive the ultrasonic transducer to emit ultrasonic signals at a frequency of f0; and a sampling circuit electrically connected with the ultrasonic transducer and configured to sample the ultrasonic signals at a sampling frequency of n*f0 to obtain a sampling signal, wherein f0 is the frequency of the ultrasonic signals, and n>1.

10. The chip of claim 9, wherein, Further comprising a downsampling module electrically connected between the low-pass filter and the amplitude calculation module, wherein the downsampling module is electrically connected with the low-pass filter to receive a filtered signal outputted by the low-pass filter and perform downsampling on the filtered signal to obtain a downsampled signal; and the amplitude calculation module is electrically connected with the downsampling module to receive the downsampled signal outputted by the downsampling module and perform amplitude calculation based on the downsampled signal to output an envelope amplitude curve.

11. The chip of claim 10, wherein, The digital down-conversion module comprises: a first frequency conversion module electrically connected with the sampling circuit to receive the sampling signal outputted by the sampling circuit and convert the sampling signal into a first mixed frequency signal; a second frequency conversion module electrically connected with the sampling circuit to receive the sampling signal outputted by the sampling circuit and convert the sampling signal into a second mixed frequency signal; wherein the local signals adopted by the first frequency conversion module and the second frequency conversion module are orthogonal to each other. The low-pass filter comprises: a first low-pass filter electrically connected with the first frequency conversion module to receive the first mixed frequency signal outputted by the first frequency conversion module and perform low-pass filtering on the first mixed frequency signal to obtain a first filtered signal; a second low-pass filter electrically connected with the second frequency conversion module to receive the second mixed frequency signal outputted by the second frequency conversion module and perform low-pass filtering on the second mixed frequency signal to obtain a second filtered signal; The downsampling module comprises: a first downsampling module electrically connected with the first low-pass filter to receive the first filtered signal outputted by the first low-pass filter and perform downsampling on the first filtered signal to obtain a first downsampled signal; a second downsampling module electrically connected with the second low-pass filter to receive the second filtered signal outputted by the second low-pass filter and perform downsampling on the second filtered signal to obtain a second downsampled signal; The amplitude calculation module is electrically connected with the first downsampling module and the second downsampling module respectively to receive the first downsampled signal outputted by the first downsampling module and the second downsampled signal outputted by the second downsampling module and perform amplitude calculation based on the first downsampled signal and the second downsampled signal to output the envelope amplitude curve.

12. An ultrasonic signal processing method applied to an ultrasonic transducer chip, the chip being configured to be electrically connected to an ultrasonic transducer, the chip receiving signals being divided into a driving phase, an aftershock phase and a receiving phase, characterized in that, The method comprises: sampling the ultrasonic signals to obtain a sampling signal; and performing amplitude calculation based on the sampling signal to output an envelope amplitude curve. digitally down-convert the sampling signal to obtain a mixed signal corresponding to the ultrasonic signal; perform low-pass filtering on the mixed signal to obtain a filtered signal; perform amplitude calculation based on the filtered signal to output an envelope amplitude curve; perform calibration processing on the envelope amplitude curve to output a final envelope curve, wherein the envelope amplitude curve is calibrated and the final envelope curve of a transition period between the driving phase and the aftershock phase is output. compare the final envelope curve with an envelope curve threshold to output a threshold comparison result.

13. The method of claim 12, wherein, The calibration processing on the envelope amplitude curve to output a final envelope curve specifically includes: If the amplitude of the envelope amplitude curve is less than a preset first amplitude threshold, the envelope amplitude curve is calibrated.

14. The method of claim 13, wherein, If the amplitude of the envelope amplitude curve is less than a preset first amplitude threshold and greater than or equal to a second amplitude threshold, a first calibration offset strategy is used to calibrate the envelope amplitude curve. If the amplitude of the envelope amplitude curve is less than the second amplitude threshold, a second calibration offset strategy is used to calibrate the envelope amplitude curve. The first amplitude threshold is greater than the second amplitude threshold. The first amplitude threshold is the maximum amplitude of the envelope amplitude curve, and / or the second amplitude threshold is half of the maximum amplitude of the envelope amplitude curve.

15. The method of claim 14, wherein, The first calibration offset strategy is P_final=(P_ev+P_cal1) / 2, and the second calibration offset strategy is P_final=(P_ev+P_cal2) / 2.

16. The method of claim 15, wherein, The first calibration factor is 1.25*P_max, and the second calibration factor is 1.5*P_max. The start point of the transition period is the end point of the driving phase, and the end point of the transition period is a point corresponding to a specified time or a specified number of cycles after the end point of the driving phase.

17. The method of claim 16, wherein, In the transition period, the envelope amplitude curve is directly outputted to form the final envelope curve. The ultrasonic transducer is driven to emit ultrasonic signals at a frequency of f0, and the ultrasonic signals are sampled at a sampling frequency of n*f0, where n>1.

18. The method of claim 12, wherein, After obtaining the filtered signal, the filtered signal is first down-sampled to obtain a down-sampled signal, and then amplitude calculation is performed based on the down-sampled signal to output an envelope amplitude curve.

19. The method of claim 12, wherein, 22. The method of claim 21, wherein 20. The method of any of claims 12-19, wherein, ​ 21. The method of claim 20, wherein, ​ ​ The digital down-conversion processing on the sampling signal to obtain a mixed frequency signal corresponding to the ultrasonic signal comprises: using mutually orthogonal local signals to convert the sampling signal into a first mixed frequency signal and a second mixed frequency signal, respectively; The low-pass filtering on the mixed frequency signal to obtain a filtered signal comprises: low-pass filtering the first mixed frequency signal and the second mixed frequency signal to obtain a first filtered signal and a second filtered signal, respectively; The down-sampling on the filtered signal to obtain a down-sampled signal comprises: down-sampling the first filtered signal and the second filtered signal to obtain a first down-sampled signal and a second down-sampled signal, respectively; The amplitude calculation according to the down-sampled signal to output an envelope amplitude curve comprises: amplitude calculation according to the first down-sampled signal and the second down-sampled signal to output the envelope amplitude curve.

23. An automotive ultrasonic radar apparatus characterized by comprising: Comprise: The chip of any one of claims 1-11; An ultrasonic transducer; Wherein, the chip and the ultrasonic transducer are electrically connected.

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