Ultrasonic compensation method and device, and ultrasonic transceiver

Abstract

The embodiment of the present application provides an ultrasonic compensation device, method and ultrasonic transceiver device, the ultraviolet compensation device includes: receiving unit, which converts acoustic signal into electrical signal;Variable gain amplifier, which carries out variable gain amplification to electrical signal;RC charge-discharge network, which outputs nonlinear control signal to the variable gain amplifier, and the nonlinear control signal controls the amplification multiple of the variable gain amplifier;And controller, which opens or closes the RC charge-discharge network, the RC charge-discharge network includes a resistor and a capacitor, two ends of the resistor are connected with the controller and the variable gain amplifier respectively, one end of the capacitor is connected between the resistor and the variable gain amplifier, and the other end of the capacitor is grounded.According to the embodiment of the present application, the gain voltage can be accurately controlled in a low-cost manner, and the measurement precision and anti-interference ability are improved.

Description

Technical Field

[0001] This application relates to the field of ultrasonic testing, and in particular to an ultrasonic compensation method, apparatus, and ultrasonic transceiver. Background Technology

[0002] Currently, ultrasonic technology is widely used, with a common application being distance measurement and object detection. For example, the time of flight of ultrasonic waves can be used to measure the distance to an object and / or detect its position. The time of flight is the time between the moment the ultrasonic transmitter emits the ultrasonic wave and the moment the ultrasonic receiver receives the returned ultrasonic wave.

[0003] Typically, a series of signal processing steps are performed on the received signal of the ultrasonic receiver to identify the returned ultrasonic signal, that is, to determine the time when the ultrasonic receiver receives the returned ultrasonic wave, thereby enabling distance measurement, object detection, and other functions.

[0004] In ultrasonic identification technology at the receiver side, the received signal is often compared with a predetermined threshold. If the received signal is greater than the predetermined threshold, it is determined that an ultrasonic signal has been received.

[0005] However, ultrasonic signals attenuate during propagation, and the attenuation characteristics of ultrasonic signals with different flight times vary greatly. In order to accurately identify the returned ultrasonic signal at the ultrasonic receiver, a variable gain amplifier is often needed to compensate for the attenuation. The goal is to achieve the same output amplitude for different received signals as much as possible, and to reproduce the sound wave signal emitted by the ultrasonic transmitter as accurately as possible.

[0006] The gain of a variable gain amplifier depends on the magnitude of the input control signal (such as a voltage signal). The larger the control signal, the larger the gain; the smaller the control signal, the smaller the gain.

[0007] It should be noted that the above introduction to the technical background is only for the purpose of providing a clear and complete explanation of the technical solutions of this application and facilitating understanding by those skilled in the art. It should not be assumed that these technical solutions are known to those skilled in the art simply because they have been described in the background section of this application. Summary of the Invention

[0008] The inventors discovered that in some existing solutions, the control signal generator produces a linear voltage signal to be input to the variable gain amplifier; that is, the voltage signal output by the control signal generator changes linearly with time, such as the output voltage signal being a rising edge signal of a triangular wave. In other existing solutions, to compensate for the exponential attenuation of ultrasound and to consider the influence of multiple factors, the control signal generator is implemented with a complex circuit structure. Furthermore, in some low-cost designs, ordinary operational amplifier circuits are used to amplify the received signal instead of a variable gain amplifier.

[0009] However, in existing control signal generators for variable gain, linear gain compensation is difficult to achieve with high precision due to the exponential attenuation of ultrasonic waves, resulting in low control accuracy. Existing exponential gain control signal generators are complex and expensive, with complicated control methods and slow detection speeds. Furthermore, schemes using ordinary operational amplifier circuits have low compensation accuracy and suffer from small dynamic range and susceptibility to saturation at close range. Therefore, achieving high-precision gain voltage control at low cost has become a key research topic in the industry.

[0010] This application provides an ultrasonic compensation device, method, and ultrasonic transceiver to achieve precise control of gain voltage in a low-cost manner and improve anti-interference capability.

[0011] According to a first aspect of the embodiments of this application, an ultrasonic compensation device is provided, the ultrasonic compensation device comprising:

[0012] The receiving unit converts acoustic signals into electrical signals;

[0013] A variable gain amplifier, which amplifies electrical signals with variable gain;

[0014] An RC charging / discharging network outputs a nonlinear control signal to the variable gain amplifier, the nonlinear control signal controlling the amplification factor of the variable gain amplifier; and

[0015] The controller, which turns the RC charging and discharging network on or off,

[0016] The RC charging and discharging network includes a resistor and a capacitor. The two ends of the resistor are connected to the controller and the variable gain amplifier, respectively. One end of the capacitor is connected between the resistor and the variable gain amplifier, and the other end of the capacitor is grounded.

[0017] In one or more embodiments, the controller controls the transmission of the acoustic signal and the controller activates the RC charging and discharging network within a predetermined time after the acoustic signal is transmitted.

[0018] In one or more embodiments, the predetermined time is any value in the range of 0.95 milliseconds to 1.05 milliseconds.

[0019] In one or more embodiments, the product of the resistance and the capacitance of the RC charge-discharge network is any value in the range of 0.874 milliseconds to 0.966 milliseconds.

[0020] According to a second aspect of the embodiments of this application, an ultrasonic transceiver is provided, the ultrasonic transceiver comprising:

[0021] The ultrasonic compensation device as described in the first aspect of the above embodiments;

[0022] A transmitting unit, connected to a controller of an ultrasonic compensation device, transmits acoustic signals to a receiving unit of the ultrasonic compensation device under the control of the controller; and

[0023] A comparator compares the output signal of the variable gain amplifier of the ultrasonic compensation device with a predetermined threshold to detect the acoustic signal emitted by the transmitting unit.

[0024] In one or more embodiments,

[0025] The receiving unit and the transmitting unit both include the same transducer. The transmitting unit uses the transducer to convert electrical signals into acoustic signals, and the receiving unit uses the transducer to convert acoustic signals into electrical signals.

[0026] According to a third aspect of the embodiments of this application, an ultrasonic compensation method is provided, the method comprising:

[0027] Receives ultrasonic waves and converts the sound wave signals into electrical signals; and

[0028] The electrical signal is amplified by a variable gain amplifier. The amplification factor of the variable gain amplifier is controlled by the output signal of an RC charging and discharging network. The RC charging and discharging network includes a resistor and a capacitor. The two ends of the resistor are connected to the controller that controls the RC charging and discharging network and the variable gain amplifier, respectively. One end of the capacitor is connected between the resistor and the variable gain amplifier, and the other end of the capacitor is grounded.

[0029] In one or more embodiments,

[0030] The RC charging and discharging network is activated within a predetermined time after the sound wave signal is emitted.

[0031] In one or more embodiments,

[0032] The predetermined time is any value within the range of 0.95 milliseconds to 1.05 milliseconds.

[0033] In one or more embodiments,

[0034] The product of the resistance R and capacitance C of the RC charging and discharging network is any value within the range of 0.874 milliseconds to 0.966 milliseconds.

[0035] One of the beneficial effects of the embodiments of this application is that: using an RC charging and discharging network including resistors and capacitors as the control signal generation circuit, it is possible to achieve precise control of gain voltage in a low-cost manner and improve anti-interference capability.

[0036] Specific embodiments of this application are disclosed in detail with reference to the following description and accompanying drawings, indicating how the principles of this application can be adopted. It should be understood that the embodiments of this application are not limited in scope. Within the spirit and scope of the appended claims, embodiments of this application include many changes, modifications, and equivalents.

[0037] The feature information described and illustrated for one embodiment may be used in the same or similar manner in one or more other embodiments, combined with feature information in other embodiments, or substituted for feature information in other embodiments.

[0038] It should be emphasized that the term "including / comprises" as used herein refers to the presence of a feature, whole, step, or component, but does not exclude the presence or addition of one or more other features, wholes, steps, or components. Attached Figure Description

[0039] Many aspects of this application can be better understood by referring to the following accompanying drawings. The components in the drawings are not drawn to scale, but are only intended to illustrate the principles of this application. Corresponding portions in the drawings may be enlarged or reduced for ease of illustration and description of certain parts of this application. Elements and features described in one drawing or embodiment of this application may be combined with elements and features shown in one or more other drawings or embodiments. Furthermore, similar reference numerals in the drawings denote corresponding components in several drawings and can be used to indicate corresponding components used in more than one embodiment.

[0040] In the attached diagram:

[0041] Figure 1 This is a schematic diagram of an ultrasonic compensation device according to an embodiment of this application;

[0042] Figure 2 This is a schematic diagram of the ultrasonic attenuation curve and RC charge-discharge curve of an embodiment of this application;

[0043] Figure 3 The charging curves corresponding to different RC constants in embodiments of this application are shown;

[0044] Figure 4 This is a schematic diagram of an ultrasonic compensation method according to an embodiment of this application;

[0045] Figure 5 This is a schematic diagram of an ultrasonic transceiver device according to an embodiment of this application;

[0046] Figure 6 This is an example diagram comparing the gain compensation control timing of the ultrasonic transceiver device according to an embodiment of this application with that of uncompensated ultrasonic transceiver. Detailed Implementation

[0047] The preferred embodiments of this application will now be described with reference to the accompanying drawings.

[0048] First aspect of the embodiments

[0049] An embodiment of the first aspect of this application provides an ultrasonic compensation device.

[0050] Figure 1 This is a schematic diagram of an ultrasonic compensation device according to an embodiment of this application. Figure 1 As shown, the ultrasonic compensation device 100 includes:

[0051] The receiving unit 101 converts the acoustic wave signal into an electrical signal;

[0052] The variable gain amplifier 102 amplifies the electrical signal with variable gain.

[0053] An RC charging / discharging network 103 outputs a nonlinear control signal to a variable gain amplifier 102, which controls the amplification factor of the variable gain amplifier 102; and

[0054] The controller 104 turns the RC charging and discharging network 103 on or off.

[0055] In this embodiment, the RC charging and discharging network 103 includes a resistor and a capacitor. The two ends of the resistor are connected to the controller 104 and the variable gain amplifier 102, respectively. One end of the capacitor is connected between the resistor and the variable gain amplifier 102, and the other end of the capacitor is grounded.

[0056] As can be seen from the above embodiments, using an RC charging and discharging network 103, which includes a resistor and a capacitor, as the control signal generation circuit can achieve precise control of the gain voltage in a low-cost manner and improve anti-interference capability. Furthermore, in the embodiments of this application, "a" can be understood as "at least one," and the number of resistors and capacitors is not limited to one. For example, the resistor can be formed by multiple resistive elements connected in series and / or in parallel, and the capacitor can be formed by multiple capacitive elements connected in series and / or in parallel, and so on.

[0057] The inventors discovered that the attenuation of ultrasound in air is theoretically exponential, but is also affected by factors such as sensor structure, emission angle, and refraction and absorption by the object being measured. In summary, ultrasound in practice is not an exponential process with a base e, as theoretically observed. Experimental data shows that its attenuation conforms more closely to the following formula:

[0058] b = K * B0 / R^2

[0059] Where K is the proportionality coefficient, a natural number greater than 0; B0 is the sound intensity at the sound source; R is the distance from the observation point to the sound source, the sound source being the transmitter and the observation point being the receiver; and b is the sound intensity at the observation point.

[0060] Figure 2 This is a schematic diagram of the ultrasonic attenuation curve and RC charge-discharge curve of an embodiment of this application.

[0061] like Figure 2 As shown, Q1 is the ultrasonic attenuation curve measured under actual conditions. Q1 shows that the ultrasonic power attenuates at a rate of 1 / x^2 over time. Since the control voltage X of the variable gain amplifier and the gain Y of the variable gain amplifier have a linear relationship of Y = X, the attenuation of ultrasonic power can be compensated by generating a characteristic equation with a control voltage of -1 / X^2 + 2b. However, the inventors found that they could not theoretically find a simple circuit to implement a control voltage with the aforementioned variation characteristics.

[0062] However, through meticulous research and observation of images, the inventor discovered that exponential and logarithmic functions exhibit a trend of changing from rapid to slow. In commonly used electronic circuits, the characteristics of PN junction current changes in semiconductors and the charging and discharging of capacitors are all related to exponential equations. Therefore, the inventor found the possibility of implementing a simple circuit with the aforementioned changing characteristics in hardware.

[0063] Furthermore, from a feasibility perspective, the inventors have found that the RC charging characteristic function is very suitable for compensating for ultrasonic attenuation and can be used as a hardware compensation method, wherein the RC charging characteristic is the charging characteristic of a charging and discharging circuit consisting of a resistor and a capacitor.

[0064] like Figure 2 As shown, Figure 2 Curve Q2 in the equation represents the charging equation E*(1-EXP(-t / RC)), and the absolute value of its derivative (rate of change) is very close to the derivative of ultrasonic attenuation. In other words, curve Q2 and curve Q1 have very similar rates of change.

[0065] Therefore, compared with the prior art, this application, by describing the above embodiments, utilizes the RC charging process to generate a control voltage for compensating the receiving gain, so that the gain of the ultrasonic receiving circuit can compensate for the input signal attenuation throughout the ultrasonic receiving time (or within the global measurement distance of the ultrasonic wave), thereby achieving stable output signal amplitude throughout the receiving phase. This enables precise control of the gain voltage at low cost and improves anti-interference capability.

[0066] In other words, because a low-cost RC circuit is used for gain voltage control, the cost is very low. Furthermore, since the RC charging characteristic curve used is very similar to the attenuation characteristics of the ultrasonic received signal, the control accuracy is significantly improved compared to other existing methods. Moreover, since signal attenuation compensation is performed through RC hardware, the load on the controller (such as a microprocessor MCU) is greatly reduced, allowing for lower MCU costs or enabling other task management at a comparable cost. Therefore, the ultrasonic compensation device of this application embodiment has advantages such as high detection accuracy, fast detection speed, low cost, and low environmental requirements.

[0067] Furthermore, ultrasonic transmitted signals are often ultrasonic pulse trains with a certain characteristic frequency and number. The received signal typically undergoes the following processing: for example, detecting the envelope signal of the received signal by integration, shaping the envelope signal, comparing the shaped envelope signal with a preset threshold, and outputting a pulse signal if the received signal is greater than the preset threshold, indicating that an ultrasonic signal has been received. In other words, due to detection accuracy issues, existing solutions generally reconstruct a single pulse from a pulse train to achieve ultrasonic detection.

[0068] In this embodiment, the RC hardware used can significantly improve control accuracy compared to other existing methods. On the receiving side, the ultrasonic signal can be restored to have the same characteristics as the transmitted wave, namely a series of pulses. Therefore, by using characteristics such as the number and interval of pulses, it is beneficial to identify interference and its own signals, thereby improving detection accuracy.

[0069] In the embodiments of this application, the ultrasonic compensation device can be applied to various devices that use ultrasonic waves for measurement, detection, etc., such as various large, medium and small sensors, as long as there is a need for control of the nonlinear variable gain of the amplification circuit in the ultrasonic receiving circuit. This application does not impose any restrictions on this.

[0070] In one or more embodiments, the controller controls the transmission of the acoustic signal and activates the RC charging and discharging network within a predetermined time after the acoustic signal is transmitted. This improves the control accuracy of ultrasonic attenuation compensation.

[0071] In this embodiment, there is a saturation period during the initial signal transmission. This means that because the ultrasonic wave has a very short flight time and minimal signal attenuation, the receiving circuit will be in a saturated state during signal reception, meaning the received signal will always be greater than a predetermined threshold. The transmitted signal normalization corresponding to this condition is as follows: Figure 2 As shown by curve Q1, it is in a saturated state for a period of time after the start (less than 1 millisecond), that is, the part of curve Q1 normalized to a constant 1. In this case, there is no need to control the amplification factor of the variable gain controller, that is, there is no need to turn on the RC charging and discharging network.

[0072] In addition, when the receiver and transmitter share the same transducer, the ultrasonic transducer rings after transmission and needs to wait for a period of time before it can start receiving. In other words, the receiver cannot start receiving immediately after the ultrasonic wave is sent due to the ringing phenomenon. In addition, there are also system factors such as the damping of the transmitting system itself, which prevent the receiver from receiving signals for a period of time after transmission.

[0073] Therefore, in this embodiment, the controller activates the RC charging and discharging network within a predetermined time after the acoustic signal is emitted, enabling appropriate charging control.

[0074] Furthermore, the inventors discovered that the ultrasonic receiver cannot receive signals for approximately 1 millisecond due to phenomena such as ringing. Therefore, the controller can activate the RC charging and discharging network approximately 1 millisecond after the sound wave signal is emitted (e.g., any value within the range of 0.95 milliseconds to 1.05 milliseconds). However, this application is not limited to this; the predetermined time can also be other values, which can be set according to actual needs.

[0075] In one or more embodiments, the product of the resistance and capacitance of the RC charging / discharging network is any value ranging from 0.874 milliseconds to 0.966 milliseconds. This enables more precise compensation control.

[0076] The inventors discovered that different values ​​of RC in the charging equation E*(1-EXP(-t / RC)) correspond to different curves, but how to determine the most suitable RC has become a problem to be solved.

[0077] To address this, the inventors adopted the following two-step process to obtain the most suitable RC:

[0078] Coarse fitting: Take multiple RC constants and calculate the changing trend of the corresponding curves. For example, take RC constants of 0.5ms, 1ms, and 1.5ms. Through calculation, it is determined that when RC = 1ms, the slope (i.e. the amount of change) in the initial time period (the initial time period is a time period with a relatively large amount of change, such as within 2ms) is very close to decay, while the other two constants of 0.5ms and 1.5ms are either too steep or too slow.

[0079] Figure 3 The charging curves corresponding to different RC constants of embodiments of this application are shown.

[0080] like Figure 3 As shown, the slope (i.e. change) of the charging curve Q11 with an RC constant of 1 ms within 2 ms is very close to that of the decay curve Q2, while the slope (i.e. change) of the charging curve Q12 with an RC constant of 0.5 ms within 2 ms is too steep, and the slope (i.e. change) of the charging curve Q13 with an RC constant of 1.5 ms within 2 ms is too slow.

[0081] Furthermore, the inventors discovered that within approximately 1 ms, due to the minimal attenuation of ultrasound, the circuit is in a saturated state. If amplification compensation is performed simultaneously after ultrasound emission, it will lead to a complete mismatch in compensation during the subsequent time period. Therefore, a delay compensation is required after ultrasound emission. Figure 3 As shown, shifting curve Q11 by approximately 1 millisecond results in the dashed curve Q14, which yields a suitable compensation result (i.e., the increase and decrease are as close as possible at each time point). This 1 millisecond corresponds to the previously predetermined time, but can also be other values, as explained above.

[0082] Next, with RC around 1 millisecond, the variance of the compensation difference was calculated by iterating over different RC times to obtain the RC value at its minimum. The inventors found that the compensation deviation at each time point was minimal when the RC constant was close to 0.92 ms. When setting specific RC parameters, 0.92 ms was used as the center value, with ±5% as the deviation, and the value range could be set from 0.874 ms to 0.966 ms. However, this application is not limited to this; RC can also take other time constants, which can be determined according to the actual situation.

[0083] In the embodiments of this application, after determining the RC time constant, the specific values ​​of R and C can be further determined based on the determined time constant.

[0084] In one or more embodiments, the resistor R can be 19.6k ohms and the capacitor C can be 47nF, but this application is not limited to this. Other values ​​of resistor R and capacitor C can also be used, as long as their product is within the range of the time constant RC. In addition, in order to reduce the influence of the internal resistance of the charging source and the influence of stray capacitance, the value of capacitor C can be larger, and the resistance of resistor R can be reduced accordingly.

[0085] In the embodiments of this application, the ultrasonic compensation device may also include other components. For example, a buffer may be provided between the RC charging and discharging network and the variable gain amplifier for output buffering and voltage matching of the RC charging and discharging network. For example, pre-amplification processing may be performed before the received signal is sent to the variable gain amplifier. This application does not limit this. For information on buffers and pre-amplification processing devices, please refer to related technologies.

[0086] As can be seen from the above embodiments, using an RC charging and discharging network 103, which includes a resistor and a capacitor, as the control signal generation circuit can achieve precise control of the gain voltage in a low-cost manner and improve the anti-interference capability.

[0087] Second aspect of the embodiments

[0088] This application provides an ultrasonic compensation method, which corresponds to the ultrasonic compensation device described in the first aspect of the embodiment.

[0089] Figure 4 This is a schematic diagram of an ultrasonic compensation method according to an embodiment of the second aspect of this application. Figure 4 As shown, the method includes:

[0090] Step 401: Receive ultrasonic waves and convert the sound wave signal into an electrical signal;

[0091] Step 402: The electrical signal is amplified by a variable gain amplifier. The amplification factor of the variable gain amplifier is controlled by the output signal of the RC charging and discharging network. The RC charging and discharging network includes a resistor and a capacitor. The two ends of the resistor are connected to the controller that controls the RC charging and discharging network and the variable gain amplifier, respectively. One end of the capacitor is connected between the resistor and the variable gain amplifier, and the other end of the capacitor is grounded.

[0092] In one or more embodiments, the RC charging and discharging network is activated within a predetermined time after the acoustic signal is emitted.

[0093] In one or more embodiments, the predetermined time is any value in the range of 0.95 milliseconds to 1.05 milliseconds.

[0094] In one or more embodiments, the product of the resistance R and capacitance C of the RC charge / discharge network is any value in the range of 0.874 milliseconds to 0.966 milliseconds.

[0095] The specific implementation method of the above steps is the same as that described in the embodiment of the first aspect, and will not be repeated here.

[0096] As can be seen from the above embodiments, by using an RC charging and discharging network 103, which includes a resistor and a capacitor, to control the gain of a variable gain amplifier, precise control of the gain voltage can be achieved in a low-cost manner, thereby improving the anti-interference capability.

[0097] Third aspect of the embodiments

[0098] This application provides an ultrasonic transceiver device, which includes the ultrasonic compensation device described in the first aspect of the embodiment. Details regarding the ultrasonic compensation device are incorporated herein and will not be repeated here.

[0099] Figure 5 This is a schematic diagram of an ultrasonic transceiver device according to an embodiment of this application.

[0100] like Figure 5 As shown, the ultrasonic transceiver 20 also includes a transmitter 201 and a comparator 202. The transmitter 201 is connected to the controller 104 of the ultrasonic compensation device 10. Under the control of the controller 104, the transmitter 201 transmits an acoustic signal to the receiver 101 of the ultrasonic compensation device 10. The comparator 202 compares the output signal of the variable gain amplifier 102 of the ultrasonic compensation device with a predetermined threshold to detect the acoustic signal transmitted by the transmitter 201.

[0101] In existing technologies, an envelope detection circuit is often placed between the comparator and the variable gain amplifier to detect the envelope of the received signal. This results in a loss of precise extraction of the pulse train frequency and number, allowing noise and interference to also be received, increasing the risk of system interference. However, in this embodiment, since high-precision attenuation compensation can be achieved through the RC charge-discharge circuit, the receiving side can identify multiple pulse signals. Therefore, the ultrasonic transceiver 20 of this embodiment does not require an envelope detection circuit, simplifying the circuit and further reducing costs.

[0102] However, this application is not limited to this. In this embodiment, the envelope signal can also be detected to identify a pulse signal as the received ultrasonic signal. Furthermore, since high-precision attenuation compensation can be achieved through the RC charging and discharging circuit, the receiving side can identify multiple pulse signals. In this embodiment, the envelope signal can also be detected to obtain a more accurate ultrasonic signal, such as a shorter delay, thereby improving the accuracy of ranging and object detection.

[0103] In one or more embodiments, the comparator 202 may also have a pulse shaping function and compare the shaped signal with a predetermined threshold to restore the characteristics of the acoustic signal emitted by the transmitter.

[0104] Figure 6 This is an example diagram comparing the gain compensation control timing of the ultrasonic transceiver device according to an embodiment of this application with that of uncompensated ultrasonic transceiver.

[0105] like Figure 5 and Figure 6 As shown, MCU 104 emits a train of ultrasonic pulses with a specific frequency and number. After being driven by DRV power, the pulse train is applied to the transducer. Following electroacoustic conversion by the transducer, the transmitting unit 201 emits ultrasonic waves. After a minute wait (approximately 1 millisecond), a control port of MCU 104 outputs a high level, charging the RC charging network 103 to generate ultrasonic waves. Figure 5 The gain compensation curve V changes exponentially with time GAIN After the ultrasonic wave is emitted, it bounces back to the receiving transducer upon encountering an object. The transducer performs an acoustic-to-electric conversion, generating a weak voltage signal. After pre-amplification, the signal enters the variable gain amplifier (VCA) 102. The control voltage of VCA 102 follows an exponential change, with the amplification increasing over time (this exponential change is generated by the RC charging / discharging network 103 and buffered to obtain a control voltage range matched to VCA 102). This ensures that signals entering VCA 102 after different time intervals (the shorter the time, the larger the signal amplitude) have the most consistent amplitude possible. VCA 102 sends the processed signal to comparator 202, compares it with a set threshold, and outputs a shaped pulse. This pulse maximally recreates the ultrasonic wave pulse train. This pulse train can be directly input to the timer input of MCU 104 via the T0 interface for counting and pulse width measurement. By comparing it with the original pulse train, not only is the presence or absence of an object determined, but it also additionally determines whether the signal is a self-reflected signal, increasing anti-interference capability.

[0106] In one or more embodiments, the receiving unit 101 and the transmitting unit 201 may include the same transducer, which the transmitting unit 201 uses to convert electrical signals into acoustic signals, and the receiving unit 101 uses the same transducer to convert acoustic signals into electrical signals. This reduces costs.

[0107] In the embodiments of this application, since the beginning and end signals of the transmitted pulse train are generally lost during the receiving process, the number of pulse trains restored at the receiving end will be 2 to 6 fewer than the transmitted pulse train. However, the intermediate process is preserved relatively completely. The number of lost pulses is a fixed number in a fixed system, so it does not affect the identification of the entire pulse train.

[0108] As can be seen from the above embodiments, by using an RC charging and discharging network 103, which includes a resistor and a capacitor, to control the gain of a variable gain amplifier, precise control of the gain voltage can be achieved in a low-cost manner, thereby improving the anti-interference capability.

[0109] The apparatus and methods described above in this application can be implemented in hardware or in combination with software. This application relates to a computer-readable program that, when executed by a logic component, enables the logic component to implement the apparatus or constituent parts described above, or to implement the various methods or steps described above.

[0110] This application also relates to storage media for storing the above programs, such as hard disks, magnetic disks, optical disks, DVDs, flash memory, etc.

[0111] The present application has been described above with reference to specific embodiments. However, those skilled in the art should understand that these descriptions are exemplary and not intended to limit the scope of protection of the present application. Those skilled in the art can make various modifications and variations to the present application based on its spirit and principles, and these modifications and variations are also within the scope of the present application.

Claims

1. An ultrasonic compensation device, characterized in that, The ultrasonic compensation device includes: The receiving unit converts acoustic wave signals into electrical signals; A variable gain amplifier, which amplifies electrical signals with variable gain; An RC charging / discharging network outputs a nonlinear control signal to the variable gain amplifier, the nonlinear control signal controlling the amplification factor of the variable gain amplifier; and A controller that turns the RC charging and discharging network on or off, and the controller turns the RC charging and discharging network on within a predetermined time after the acoustic signal is emitted. The RC charging and discharging network includes a resistor and a capacitor. The two ends of the resistor are connected to the controller and the variable gain amplifier, respectively. One end of the capacitor is connected between the resistor and the variable gain amplifier, and the other end of the capacitor is grounded.

2. The ultrasonic compensation device according to claim 1, characterized in that, The controller controls the transmission of the acoustic signal.

3. The ultrasonic compensation device according to claim 2, characterized in that, The predetermined time is any value within the range of 0.95 milliseconds to 1.05 milliseconds.

4. The ultrasonic compensation device according to claim 1, characterized in that... The product of the resistance and the capacitance of the RC charging and discharging network is any value within the range of 0.874 milliseconds to 0.966 milliseconds.

5. An ultrasonic transceiver, characterized in that, The ultrasonic transceiver includes: The ultrasonic compensation device as described in any one of claims 1 to 4; A transmitting unit, connected to a controller of an ultrasonic compensation device, transmits acoustic signals to a receiving unit of the ultrasonic compensation device under the control of the controller; and A comparator compares the output signal of the variable gain amplifier of the ultrasonic compensation device with a predetermined threshold to detect the acoustic wave signal emitted by the transmitting unit.

6. The ultrasonic transceiver according to claim 5, characterized in that, The receiving unit and the transmitting unit both include the same transducer. The transmitting unit uses the transducer to convert electrical signals into acoustic signals, and the receiving unit uses the transducer to convert acoustic signals into electrical signals.

7. An ultrasonic compensation method, characterized in that, The ultrasonic compensation method includes: Receives ultrasonic waves and converts the sound wave signals into electrical signals; and The electrical signal is amplified by a variable gain amplifier, the amplification factor of which is controlled by the output signal of an RC charging and discharging network. The RC charging and discharging network is activated within a predetermined time after the acoustic signal is emitted. The RC charging and discharging network includes a resistor and a capacitor. The two ends of the resistor are connected to the controller that controls the RC charging and discharging network and the variable gain amplifier, respectively. One end of the capacitor is connected between the resistor and the variable gain amplifier, and the other end of the capacitor is grounded.

8. The ultrasonic compensation method according to claim 7, characterized in that, The predetermined time is any value within the range of 0.95 milliseconds to 1.05 milliseconds.

9. The ultrasonic compensation method according to claim 7, characterized in that, The product of the resistance R and capacitance C of the RC charging and discharging network is any value within the range of 0.874 milliseconds to 0.966 milliseconds.

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