Methods, circuits, chips, and devices for echo signal processing of ultrasonic sensors

Abstract

This application provides a method, circuit, chip, and device for processing echo signals from an ultrasonic sensor. The echo signal processing circuit includes a differential circuit, a symbol extraction circuit, a second delay circuit, a logic operation circuit, a peak output circuit, and a threshold comparison circuit. In this application embodiment, a differential method is used to compare the ultrasonic echo signal and the delayed signal of the ultrasonic echo signal. The comparison result is then subjected to symbol extraction. The moment of peak occurrence is obtained through the analysis of the symbol signal, thereby obtaining the peak signal. Since the extraction of this peak signal is independent of the selected time period, the accuracy of peak signal extraction is greatly improved, thus making the determination of obstacle distance more accurate.

Description

Technical Field

[0001] This application relates to the field of electronic technology, and specifically to a method, circuit, chip, and device for processing echo signals of an ultrasonic sensor. Background Technology

[0002] 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 signals with frequencies of 20 kHz or higher (which are inaudible), the ultrasonic sensor can sense the ultrasonic echo signals reflected from external obstacles and analyze the echo signals to determine the distance between the ultrasonic sensor 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.

[0003] In existing technologies, ultrasonic echo signals received by ultrasonic sensors are typically divided into multiple time periods. The peak value of the ultrasonic echo signal is determined within each time period, and this peak value is analyzed to determine the distance to the obstacle. However, dividing the ultrasonic echo signal into multiple time periods and using signal processing techniques to determine the peak value within each time period is cumbersome. Furthermore, due to the uncertainty of the starting point within each time period, the peak value detected within that time period may not be the true peak value, thus affecting the accuracy of the detection results. Summary of the Invention

[0004] In view of this, this application provides an echo signal processing method, circuit, chip, and device for an ultrasonic sensor, which helps to solve the problem that in the prior art, the ultrasonic echo signal is divided into multiple time periods, and the peak value is determined by signal processing technology within each time period. This process is relatively cumbersome, and due to the uncertainty of the starting point of the time period, the peak value detected within the time period is not the true peak value, thus affecting the accuracy of the detection results.

[0005] In a first aspect, embodiments of this application provide an echo signal processing circuit for an ultrasonic sensor, comprising:

[0006] A differential circuit, comprising a first delay circuit and a difference calculation circuit, wherein the first delay circuit is used to delay the received ultrasonic echo signal d_in[i] by a first time to obtain a delayed signal d_in[i-1] of the ultrasonic echo signal; and the difference calculation circuit is used to perform difference calculation between the ultrasonic echo signal d_in[i] and the delayed signal d_in[i-1] of the ultrasonic echo signal to obtain a differential signal diff[i].

[0007] A symbol extraction circuit is used to mark the part of the differential signal diff[i] that is greater than 0 as a first symbol and mark the part of the differential signal diff[i] that is less than 0 as a second symbol, so as to obtain the symbol signal sign[i] corresponding to the differential signal diff[i].

[0008] The second delay circuit is used to delay the symbol signal sign[i] by a second time to obtain the delayed signal sign[i-1] of the symbol signal;

[0009] A logic operation circuit is used to output an enable signal A when the symbol signal sign[i] and the delayed signal sign[i-1] of the symbol signal are different and the enable signal output condition is met;

[0010] A peak output circuit is used to output a peak signal, wherein the peak signal is the signal corresponding to the ultrasonic echo signal d_in[i] or the delayed signal d_in[i-1] of the ultrasonic echo signal when the enable signal A is received;

[0011] A threshold comparison circuit is used to compare the peak signal with a peak signal threshold and output a comparison result. The comparison result is used to: determine that a valid echo signal has been received when the first comparison result meets the valid echo signal determination rule. The first comparison result is the comparison result that the peak signal is greater than or equal to the peak signal threshold. The valid echo signal is used to determine the distance to the obstacle.

[0012] Secondly, embodiments of this application provide a method for processing echo signals from an ultrasonic sensor, including:

[0013] The received ultrasonic echo signal d_in[i] is delayed by a first time to obtain the delayed signal d_in[i-1] of the ultrasonic echo signal;

[0014] The difference between the ultrasonic echo signal d_in[i] and the delayed signal d_in[i-1] of the ultrasonic echo signal is calculated to obtain the differential signal diff[i].

[0015] The portion of the differential signal diff[i] that is greater than 0 is marked as the first symbol, and the portion of the differential signal diff[i] that is less than 0 is marked as the second symbol, thereby obtaining the symbol signal sign[i] corresponding to the differential signal diff[i].

[0016] The symbol signal sign[i] is delayed by a second time to obtain the delayed signal sign[i-1] of the symbol signal;

[0017] When the symbol signal sign[i] and the delayed signal sign[i-1] of the symbol signal are different and the enable signal output condition is met, the enable signal A is output;

[0018] Output a peak signal, which is the signal corresponding to the ultrasonic echo signal d_in[i] or the delayed signal d_in[i-1] of the ultrasonic echo signal when the enable signal A is received;

[0019] The peak signal is compared with the peak signal threshold and the comparison result is output. The comparison result is used to: determine that a valid echo signal has been received when the first comparison result meets the valid echo signal determination rule. The first comparison result is the comparison result that the peak signal is greater than or equal to the peak signal threshold. The valid echo signal is used to determine the distance to the obstacle.

[0020] Thirdly, embodiments of this application provide an ultrasonic sensor chip, comprising:

[0021] A differential circuit includes a first delay circuit and a difference calculation circuit. The signal output terminal of the first delay circuit is electrically connected to the first signal input terminal of the difference calculation circuit, and the signal input terminal of the first delay circuit is electrically connected to the second signal input terminal of the difference calculation circuit. The first delay circuit is used to delay the received ultrasonic echo signal d_in[i] by a first time to obtain the delayed signal d_in[i-1] of the ultrasonic echo signal. The difference calculation circuit is used to perform difference calculation between the ultrasonic echo signal d_in[i] and the delayed signal d_in[i-1] of the ultrasonic echo signal to obtain the differential signal diff[i].

[0022] A symbol extraction circuit is provided, wherein the signal input terminal of the symbol extraction circuit is electrically connected to the first signal output terminal of the differential circuit. The symbol extraction circuit is used to mark the part of the differential signal diff[i] that is greater than 0 as the first symbol and mark the part of the differential signal diff[i] that is less than 0 as the second symbol, thereby obtaining the symbol signal sign[i] corresponding to the differential signal diff[i].

[0023] The second delay circuit is electrically connected to the signal output of the symbol extraction circuit. The second delay circuit is used to delay the symbol signal sign[i] by a second time to obtain the delayed signal sign[i-1] of the symbol signal.

[0024] A logic operation circuit, wherein the first signal input terminal of the logic operation circuit is electrically connected to the signal output terminal of the symbol extraction circuit, and the second signal input terminal of the logic operation circuit is electrically connected to the signal output terminal of the second delay circuit. The logic operation circuit is used to output an enable signal A when the symbol signal sign[i] and the delay signal sign[i-1] of the symbol signal are different and the enable signal output condition is met.

[0025] A peak output circuit, wherein the signal input terminal of the peak output circuit is electrically connected to the second signal output terminal of the differential circuit, and the control terminal of the peak output circuit is electrically connected to the signal output terminal of the logic operation circuit, the peak output circuit is used to output a peak signal, wherein the peak signal is the signal corresponding to the ultrasonic echo signal d_in[i] or the delayed signal d_in[i-1] of the ultrasonic echo signal when the enable signal A is received;

[0026] A threshold comparison circuit is provided, wherein the signal input terminal of the threshold comparison circuit is electrically connected to the signal output terminal of the peak output circuit. The threshold comparison circuit is used to compare the peak signal with a peak signal threshold and output a comparison result. The comparison result is used to determine that a valid echo signal has been received when the first comparison result meets the valid echo signal determination rule. The first comparison result is the comparison result that the peak signal is greater than or equal to the peak signal threshold. The valid echo signal is used to determine the distance to the obstacle.

[0027] Fourthly, embodiments of this application provide an ultrasonic radar device, comprising:

[0028] The ultrasonic sensor chip described in any of the third aspects;

[0029] An ultrasonic sensor is used to emit ultrasonic signals based on ultrasonic excitation signals and to receive ultrasonic echo signals d_in[i].

[0030] In this embodiment, a differential method is used to compare the ultrasonic echo signal and its delayed signal. The comparison result is then subjected to symbol extraction. The moment of peak occurrence is obtained through symbol signal analysis, thereby obtaining the peak signal. Since the extraction of this peak signal is independent of the selected time period, the accuracy of peak signal extraction is greatly improved, thus making the determination of obstacle distance more accurate. Attached Figure Description

[0031] 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.

[0032] Figure 1 This is a schematic diagram of an application scenario provided by an embodiment of this application;

[0033] Figure 2A This is a schematic diagram of the ranging principle of an ultrasonic system provided in an embodiment of this application;

[0034] Figure 2B This is a schematic diagram of the ranging principle of another ultrasonic system provided in an embodiment of this application;

[0035] Figure 3A A structural block diagram of an echo signal processing circuit for an ultrasonic sensor provided in an embodiment of this application;

[0036] Figure 3B A structural block diagram of an echo signal processing circuit for another ultrasonic sensor provided in an embodiment of this application;

[0037] Figure 4 A structural block diagram of a differential circuit provided in an embodiment of this application;

[0038] Figure 5 This is a schematic diagram of a peak signal extraction scenario provided in an embodiment of this application;

[0039] Figure 6 This is a schematic diagram of another peak signal extraction scenario provided in an embodiment of this application;

[0040] Figure 7 This is a block diagram of another differential circuit provided in an embodiment of this application;

[0041] Figure 8 This is a block diagram of another differential circuit provided in an embodiment of this application;

[0042] Figure 9 A partial structural block diagram of an echo signal processing circuit for an ultrasonic sensor provided in an embodiment of this application;

[0043] Figure 10 This is a schematic diagram of another peak signal extraction scenario provided in an embodiment of this application;

[0044] Figure 11 This is a schematic diagram of another peak signal extraction scenario provided in an embodiment of this application;

[0045] Figure 12 This is a schematic diagram of another peak signal extraction scenario provided in an embodiment of this application;

[0046] Figure 13 This is a schematic diagram of another peak signal extraction scenario provided in an embodiment of this application;

[0047] Figure 14 This is a schematic diagram of another peak signal extraction scenario provided in an embodiment of this application;

[0048] Figure 15 This is a schematic diagram of another peak signal extraction scenario provided in an embodiment of this application;

[0049] Figure 16 This is a schematic diagram of another peak signal extraction scenario provided in an embodiment of this application;

[0050] Figure 17 This is a schematic diagram of another peak signal extraction scenario provided in an embodiment of this application;

[0051] Figure 18 A flowchart illustrating an echo signal processing method for an ultrasonic sensor provided in an embodiment of this application;

[0052] Figure 19 A structural block diagram of an ultrasonic radar device provided in an embodiment of this application;

[0053] Figure 20 This is a structural block diagram of another ultrasonic radar device provided in an embodiment of this application. Detailed Implementation

[0054] 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.

[0055] 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.

[0056] 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.

[0057] 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.

[0058] See Figure 1 This is a schematic diagram illustrating an application scenario provided in 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 sensors 101. When the user controls the vehicle 100 to reverse, the ultrasonic sensors 101 can emit ultrasonic signals and receive ultrasonic echo signals (the ultrasonic sensors can be different sensors that emit and receive ultrasonic waves, or they can both emit and receive ultrasonic waves). The distance between the ultrasonic sensors 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.

[0059] 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 application 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 sensors 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 using four ultrasonic sensors, more or fewer ultrasonic sensors can be used, etc. This application does not impose specific limitations in these respects.

[0060] See Figure 2A This is a schematic diagram illustrating the ranging principle of an ultrasonic system provided in an embodiment of this application. Figure 2AThe diagram illustrates an ultrasonic sensor chip and an ultrasonic sensor, wherein the ultrasonic sensor includes an ultrasonic transmitting sensor and an ultrasonic receiving sensor. When distance detection is required, the main control circuit of the ultrasonic sensor chip receives a trigger signal from a host computer (such as a main control ECU; in this patent, a microprocessor chip is used) and controls the drive circuit to generate an ultrasonic excitation signal. This excitation signal drives the ultrasonic transmitting sensor to emit an ultrasonic signal. When the ultrasonic signal encounters an obstacle, it is emitted, and the ultrasonic receiving sensor begins to receive the ultrasonic echo signal. Due to environmental interference and interference from other ultrasonic sensors, the ultrasonic echo signal received by the ultrasonic receiving sensor is filtered and amplified. The filtering precision here can be improved to filter out ultrasonic echo signals of a specified frequency. Alternatively, high-pass, low-pass, or band-pass filters can be used to retain only ultrasonic echo signals within a specified frequency range. The processed ultrasonic echo signal is then input to an ADC for further processing. The digital signal output from the ADC is then input to a matched filter for matched filtering (matched filtering can also be understood as selecting or filtering out the desired echo signal), detecting waves with the same frequency (if the filter is fine enough to detect waves of the specified frequency, matched filtering can be omitted). The resulting digital signal is then input to a peak extractor to extract the peak value. When the peak extractor input is an analog signal, the ADC can be discarded (generally, the ADC is retained, and the analog signal is converted to a digital signal for processing; after processing, the digital signal is then converted back to digital). (Alternatively, analog signals can be compared). The peak extractor outputs the peak signal to the threshold comparison circuit. The threshold comparison circuit compares the peak signal with a preset threshold and outputs the comparison result. This comparison result is used to determine whether a valid echo signal emitted by the ultrasonic transmitter and reflected by the obstacle has been received when the specified result is obtained. The output result of the threshold comparison circuit can be directly sent to the host computer. The host computer determines whether a valid echo signal has appeared based on the comparison result. The main control circuit can calculate the distance to the obstacle based on the relationship between its timer's timing and the ultrasonic transmission speed. After obtaining the distance information, the main control circuit outputs a signal. The external ECU or controller makes a judgment and takes corresponding actions based on the received signal, such as triggering a buzzer to emit a prompt sound or displaying it on the screen. In this embodiment, it is not necessary to... Figure 2A The timer shown.

[0061] See Figure 2B This is a schematic diagram of the ranging principle of another ultrasonic system provided in the embodiments of this application. Figure 2B and Figure 2AThe difference lies in the fact that the main control circuit of the ultrasonic sensor chip also includes a judgment circuit. This judgment circuit is electrically connected to the threshold comparison circuit. The judgment circuit receives the comparison result output by the threshold comparison circuit and determines whether the comparison result is the specified result. If the comparison result is the specified result, it determines that a valid echo signal has been received and generates a feedback signal to the microprocessor chip. Figure 2B (Not shown in the image), and then the microprocessor chip calculates the distance to the obstacle based on the feedback signal. When the microprocessor chip calculates the distance, a timer in the main control circuit can also be set. If the distance is calculated by an ultrasonic sensor chip, the main control circuit can also include a timer. The main control circuit can calculate the distance to the obstacle based on the relationship between the timer's duration and the ultrasonic transmission speed. Different obstacle distances result in different feedback signals from the main control circuit. When the microprocessor chip receives these different feedback signals, it triggers a buzzer to emit a warning sound or displays an information on the screen. Other content related to the embodiments of this application can be found in [reference needed]. Figure 2A The description of the illustrated embodiment is omitted here for brevity. The timing module is set in the corresponding module that calculates the distance. Figure 2A and 2B Depending on the specific function, the corresponding timer in the middle can be omitted, and the timer can also be used for other functions, as described below.

[0062] It should be noted that in some possible implementations, the ultrasonic transmitting sensor and the ultrasonic receiving sensor can also be a single ultrasonic sensor, that is, a single ultrasonic sensor is used to both transmit ultrasonic signals and receive ultrasonic echo signals. This application does not limit this.

[0063] Furthermore, the division of functional units in Figure 2 is merely illustrative and should not be construed as limiting the scope of protection of this application. For example, the timer and / or threshold comparison circuit may not be included in the main control circuit.

[0064] In existing technologies, ultrasonic echo signals received by ultrasonic sensors are typically divided into multiple time periods. The peak value of the ultrasonic echo signal is determined within each time period, and this peak value is analyzed to determine the distance to the obstacle. However, dividing the ultrasonic echo signal into multiple time periods and using signal processing techniques to determine the peak value within each time period is cumbersome. Furthermore, due to the uncertainty of the starting point within each time period, the peak value detected within that time period may not be the true peak value, thus affecting the accuracy of the detection results.

[0065] To address the aforementioned problems, this application provides an echo signal processing scheme for an ultrasonic sensor. It employs a differential method to compare the ultrasonic echo signal and its delayed signal, extracts the symbol from the comparison result, and determines the time of peak occurrence through symbol signal analysis, thereby obtaining the peak signal. Since the extraction of this peak signal is independent of the selected time period, it greatly improves the accuracy of peak signal extraction, thus making the determination of obstacle distance more accurate. This will be described in detail below.

[0066] See Figure 3A This is a structural block diagram of an echo signal processing circuit for an ultrasonic sensor provided in an embodiment of this application. Figure 3A As shown, the echo signal processing circuit of the ultrasonic sensor includes a peak extractor and a threshold comparison circuit 306. The peak extractor further includes a differential circuit 301, a symbol extraction circuit 302, a second delay circuit 303, a logic operation circuit 304, and a peak output circuit 305. For ease of understanding, the connection relationship of each functional module is first introduced below.

[0067] The first signal output terminal of the differential circuit 301 is electrically connected to the signal input terminal of the symbol extraction circuit 302, and the second signal output terminal of the differential circuit 301 is electrically connected to the signal input terminal of the peak output circuit 305. The signal output terminal of the symbol extraction circuit 302 is electrically connected to the signal input terminal of the second delay circuit 303 and the first signal input terminal of the logic operation circuit 304, respectively. The signal output terminal of the second delay circuit 303 is electrically connected to the second signal input terminal of the logic operation circuit 304. The signal input terminal of the logic operation circuit 304 is electrically connected to the control terminal of the peak output circuit 305. The signal output terminal of the peak output circuit 305 is electrically connected to the signal input terminal of the threshold comparison circuit 306.

[0068] See Figure 4 This is a structural block diagram of a differential circuit 301 provided in an embodiment of this application. Figure 4 As shown, the differential circuit 301 includes a first delay circuit 3011 and a difference calculation circuit 3012. The signal output terminal of the first delay circuit 3011 is electrically connected to the first signal input terminal of the difference calculation circuit 3012, and the signal input terminal of the first delay circuit 3011 is electrically connected to the second signal input terminal of the difference calculation circuit 3012. The signal input terminal of the first delay circuit 3011, i.e., the signal input terminal of the differential circuit 301, is used to input the ultrasonic echo signal d_in[i]. The first delay circuit 3011 is used to delay the received ultrasonic echo signal d_in[i] by a first time Δt1 to obtain the delayed signal d_in[i-1] of the ultrasonic echo signal, as shown below. Figure 5 (5a) and Figure 6As shown in (6a) above. In a specific implementation, the first time Δt1 can be 1-n clock cycles, where n≥1. Those skilled in the art can set the duration of the first time Δt1 according to actual needs. It can be understood that the shorter the delay time of the ultrasonic echo signal d_in[i], the more accurate the detection result. In a preferred implementation, the first time Δt1 is set to one clock cycle, that is, the ultrasonic echo signal d_in[i] and the delayed signal d_in[i-1] of the ultrasonic echo signal differ by one clock cycle. This setting can greatly improve the extraction error of the peak signal and obtain a more accurate peak signal.

[0069] After the first delay circuit 3011 obtains the delayed signal d_in[i-1] of the ultrasonic echo signal, it inputs the delayed signal d_in[i-1] into the difference calculation circuit 3012. The difference calculation circuit 3012 calculates the difference between the ultrasonic echo signal d_in[i] and the delayed signal d_in[i-1] to obtain the difference signal diff[i]. In specific implementation, the ultrasonic echo signal d_in[i] can be used as the minuend, and the delayed signal d_in[i-1] can be used as the subtrahend to calculate the difference and obtain the difference signal diff[i]. Figure 5 As shown in (5b); or, using the delayed ultrasonic echo signal d_in[i-1] as the minuend and the ultrasonic echo signal d_in[i] as the subtrahend, the difference signal diff[i] is obtained, as shown in (5b). Figure 6 As shown in (6b).

[0070] The signal output terminal of the difference calculation circuit 3012 involved in this application embodiment, namely the first signal output terminal of the differential circuit 301, is used to output the differential signal diff[i]. The second signal output terminal of the differential circuit 301 is connected to the node between the signal input terminal of the first delay circuit 3011 and the second signal input terminal of the difference calculation circuit 3012, and is used to output the ultrasonic echo signal d_in[i]. Since the second signal output terminal of the differential circuit 301 outputs the ultrasonic echo signal d_in[i], the peak signal can be extracted from the ultrasonic echo signal d_in[i] in subsequent steps.

[0071] See Figure 7 This is a structural block diagram of another differential circuit 301 provided in an embodiment of this application. Figure 4The difference in the illustrated embodiment is that, in this embodiment, the second signal output terminal of the differential circuit 301 is connected to the node between the signal output terminal of the first delay circuit 3011 and the first signal input terminal of the difference calculation circuit 3012, and is used to output the delayed signal d_in[i-1] of the ultrasonic echo signal, that is, the peak signal is extracted from the delayed signal d_in[i-1] of the ultrasonic echo signal in subsequent steps. For specific details regarding the embodiments of this application, please refer to... Figure 4 The description of the embodiments shown is omitted here for the sake of brevity.

[0072] It should be noted that the peak signal extracted from the ultrasonic echo signal d_in[i] is a data point close to the actual peak value; the peak signal extracted from the delayed ultrasonic echo signal d_in[i-1] is a data point at the actual peak value. Therefore, extracting the peak signal from the delayed ultrasonic echo signal d_in[i-1] can ensure the timing alignment of the entire system.

[0073] Please continue reading. Figure 4 From the above text Figure 4 As can be seen from the introduction, in Figure 4 In the illustrated embodiment, the second signal output terminal of the differential circuit 301 outputs an ultrasonic echo signal d_in[i], meaning that the peak signal can be extracted from the ultrasonic echo signal d_in[i] in subsequent steps. In this application scenario, to achieve timing alignment of the entire system, [further steps can be taken]. Figure 4 A third delay circuit 3013 is added to the embodiment shown, which will be described in detail below.

[0074] See Figure 8 This is a structural block diagram of another differential circuit 301 provided in an embodiment of this application. Figure 4 The difference in the illustrated embodiment is that, in this embodiment, the differential circuit 301 further includes a third delay circuit 3013. Specifically, the signal input terminal of the third delay circuit 3013 is connected to the node between the signal input terminal of the first delay circuit 3011 and the second signal input terminal of the difference calculation circuit 3012, and the signal output terminal of the third delay circuit 3013 is the second signal output terminal of the differential circuit 301. It can be understood that the signal input terminal of the third delay circuit 3013 is used to input the ultrasonic echo signal d_in[i]. After being delayed by a third time Δt3 by the third delay circuit 3013, the delayed signal d_in[i-1] of the ultrasonic echo signal is output. That is, in subsequent steps, the peak signal is extracted through the delayed signal d_in[i-1] of the ultrasonic echo signal, so that the timing of the entire system is aligned.

[0075] In some possible implementations, the first time Δt1 and the third time Δt3 are equal, meaning the delay times of the first delay circuit 3011 and the third delay circuit 3013 are the same. Therefore, the delayed signal d_in[i-1] of the ultrasonic echo signal obtained by delaying through the first delay circuit 3011 is the same signal as the delayed signal d_in[i-1] of the ultrasonic echo signal obtained by delaying through the third delay circuit 3013. In specific implementations, both the first time Δt1 and the third time Δt3 can be one clock cycle. For more details regarding the embodiments of this application, please refer to [link to relevant documentation]. Figure 4 The description of the illustrated embodiments is omitted here for the sake of brevity. Figure 7 and Figure 8 The desired effect is the same.

[0076] See Figure 9 This is a partial structural block diagram of an echo signal processing circuit for an ultrasonic sensor provided in an embodiment of this application. Figure 8 The difference in the illustrated embodiment is that, in this embodiment, the third delay circuit 3013 is disposed outside the differential circuit 301. Specifically, the signal input terminal of the third delay circuit 3013 is electrically connected to the second signal output terminal of the differential circuit 301. That is, after the second signal output terminal of the differential circuit 301 outputs the ultrasonic echo signal d_in[i], the third delay circuit 3013 outputs the delayed signal d_in[i-1] of the ultrasonic echo signal after a third delay. In subsequent steps, the peak signal is extracted through the delayed signal d_in[i-1] of the ultrasonic echo signal, thereby aligning the timing of the entire system. For specific details regarding the embodiments of this application, please refer to [link to relevant documentation]. Figure 8 The description of the illustrated embodiments is omitted here for the sake of brevity. Figure 9 The effect of performance and Figure 8 Consistent. Figure 7 , 8 The final inputs to the peak output circuit 305 are both delayed signals of d_in[i]. When the delay time of the third delay circuit 3013 is the same as that of the first delay circuit 3011, the only difference is the circuit connection and division method. In essence, both are feasible and within the scope of protection of this patent.

[0077] Please continue reading. Figure 3A The signal input terminal of the symbol extraction circuit 302 receives the differential signal diff[i] output from the first signal output terminal of the differential circuit 301, and performs symbol extraction on the differential signal diff[i]. Specifically, the part of the differential signal diff[i] that is greater than 0 is marked as the first symbol, and the part of the differential signal diff[i] that is less than 0 is marked as the second symbol, thereby obtaining the symbol signal sign[i] corresponding to the differential signal diff[i].

[0078] In one possible implementation, the first symbol is 1 and the second symbol is 0. That is, the portion of the differential signal diff[i] greater than 0 is marked as "1"; the portion of the differential signal diff[i] less than 0 is marked as "0", thus obtaining the symbol signal sign[i] corresponding to the differential signal diff[i]. Figure 5 (5c) and Figure 6 As shown in (6c).

[0079] Of course, those skilled in the art can also use other rules to set the first and second symbols, and the embodiments of this application do not impose specific limitations on this. For example, the first symbol is 0 and the second symbol is 1, that is, the part of the differential signal diff[i] greater than 0 is marked as "0"; and the part of the differential signal diff[i] less than 0 is marked as "1". Or, the first symbol is 1 and the second symbol is -1, that is, the part of the differential signal diff[i] greater than 0 is marked as "1"; and the part of the differential signal diff[i] less than 0 is marked as "-1". Or, the first symbol is 0 and the second symbol is -1, that is, the part of the differential signal diff[i] greater than 0 is marked as "0"; and the part of the differential signal diff[i] less than 0 is marked as "-1". It can be understood that it can also be any number other than 1 and 0.

[0080] Please continue reading. Figure 3A The signal input terminal of the second delay circuit 303 receives the symbol signal sign[i] output from the signal output terminal of the symbol extraction circuit 302. The second delay circuit 303 delays the symbol signal sign[i] by a second time Δt2 to obtain the delayed signal sign[i-1] of the symbol signal, such as... Figure 5 (5d) and Figure 6 As shown in (6d) in the figure. In the specific implementation, the second time Δt2 can be 1-n clock cycles, where n≥1. Those skilled in the art can set the duration of the first time Δt2 according to actual needs.

[0081] In one possible implementation, the first time Δt1 and the second time Δt2 are equal, that is, the delay time of the first delay circuit 3011 for the ultrasonic echo signal d_in[i] and the delay time of the second delay circuit 303 for the symbol signal sign[i] are equal. Delaying the ultrasonic echo signal d_in[i] and the symbol signal sign[i] by the same time can reduce the processing complexity of the circuit. In a specific implementation, the first time Δt1 and the second time Δt2 can both be one clock cycle.

[0082] The first signal input terminal of the logic operation circuit 304 receives the symbol signal sign[i] output by the signal output terminal of the symbol extraction circuit 302. The second signal input terminal of the logic operation circuit 304 receives the delayed signal sign[i-1] of the symbol signal output by the signal output terminal of the second delay circuit 303. The logic operation circuit 304 performs logical operations on the symbol signal sign[i] and the delayed signal sign[i-1], and outputs the corresponding enable signal according to the result of the logical operation.

[0083] In one possible implementation, when the symbol signal sign[i] and its delayed signal sign[i-1] are different and the enable signal output condition is met, enable signal A is output; otherwise, enable signal B is output. Specifically, the enable signal output condition includes a first enable signal output condition, a second enable signal output condition, or a third enable signal output condition; when the first or second enable signal output condition is not met, enable signal B is output. The enable signal can control the signal output of the peak output circuit 305, which will be described in detail below.

[0084] Please continue reading. Figure 5 (5a) and Figure 6 In (6a), it can be seen from the waveform diagrams of the ultrasonic echo signal d_in[i] and the delayed ultrasonic echo signal d_in[i-1] that the peak signal may be either a peak signal or a trough signal. In practical applications, only the peak signal can be extracted to determine the obstacle distance; or only the trough signal can be extracted to determine the obstacle distance; or both the peak and trough signals can be extracted to determine the obstacle distance. Therefore, based on different peak signal extraction requirements, the enable signal output conditions can be divided into the following three types.

[0085] First enable signal output condition:

[0086] The symbol signal sign[i] is the second symbol, and the delayed signal sign[i-1] is the first symbol. Under this enable signal output condition, only the peak signal or the trough signal can be extracted.

[0087] Under the condition of the first enable signal output, whether the extracted peak signal is a peak signal or a trough signal depends on the subtrahend and minuend relationship between the ultrasonic echo signal d_in[i] and the delayed signal d_in[i-1] of the ultrasonic echo signal in the difference calculation circuit 3012, as well as the values ​​of the first and second symbols.

[0088] For example, in Figure 5In the application scenario shown, the ultrasonic echo signal d_in[i] is used as the minuend, and the delayed ultrasonic echo signal d_in[i-1] is used as the subtrahend; the first sign value is 1, and the second sign value is 0. Correspondingly, the first enable signal output condition is: when sign[i] = 0 and sign[i-1] = 1, enable signal 1 is output, i.e., enable signal A. In subsequent steps, the peak output circuit 305 outputs the delayed ultrasonic echo signal d_in[i-1] corresponding to the moment enable signal 1, obtaining... Figure 5 The peak signal shown in (5f) is shown in the image. That is to say, in... Figure 5 In the application scenario shown, only the peak signal is extracted under the condition of the first enable signal output.

[0089] For example, in Figure 11 In the application scenario shown, the delayed ultrasonic echo signal d_in[i-1] is used as the minuend, and the ultrasonic echo signal d_in[i] is used as the subtrahend; the first sign value is 1, and the second sign value is 0. Correspondingly, the first enable signal output condition is: when sign[i] = 0 and sign[i-1] = 1, enable signal 1 is output, i.e., enable signal A. In subsequent steps, the peak output circuit 305 outputs the delayed ultrasonic echo signal d_in[i-1] corresponding to the moment enable signal 1, obtaining... Figure 11 The trough signal is shown in (11f). That is to say, in Figure 11 In the application scenario shown, under the condition of the first enable signal output, only the trough signal is extracted.

[0090] It should be pointed out that, in Figure 5 and Figure 11 In the application scenario shown, the first symbol has a value of 1 and the second symbol has a value of 0. It can be understood that if the first symbol has a value of 0 and the second symbol has a value of 1, then under the condition that other conditions remain unchanged, the final extracted peak signal will also be reversed (the peak signal and the trough signal are reversed). For the sake of simplicity, this will not be elaborated here.

[0091] Second enable signal output condition:

[0092] The symbol signal sign[i] is the first symbol and the delayed signal sign[i-1] of the symbol signal is the second symbol.

[0093] Under the condition of the second enable signal output, whether the extracted peak signal is a peak signal or a trough signal depends on the subtrahend and minuend relationship between the ultrasonic echo signal d_in[i] and the delayed signal d_in[i-1] of the ultrasonic echo signal in the difference calculation circuit 3012, as well as the values ​​of the first and second symbols.

[0094] For example, in Figure 6 In the application scenario shown, the delayed ultrasonic echo signal d_in[i-1] is used as the minuend, and the ultrasonic echo signal d_in[i] is used as the subtrahend; the first sign value is 1, and the second sign value is 0. Correspondingly, the second enable signal output condition is: when sign[i] = 1 and sign[i-1] = 0, enable signal 1 is output, i.e., enable signal A. In subsequent steps, the peak output circuit 305 outputs the delayed ultrasonic echo signal d_in[i-1] corresponding to the moment enable signal 1, obtaining... Figure 6 The peak signal shown in (6f) is shown in the image. That is to say, in... Figure 6 In the application scenario shown, only the peak signal is extracted under the condition of the second enable signal output.

[0095] For example, in Figure 10 In the application scenario shown, the ultrasonic echo signal d_in[i] is used as the minuend, and the delayed ultrasonic echo signal d_in[i-1] is used as the subtrahend; the first sign value is 1, and the second sign value is 0. Correspondingly, the second enable signal output condition is: when sign[i] = 1 and sign[i-1] = 0, enable signal 1 is output, i.e., enable signal A. In subsequent steps, the peak output circuit 305 outputs the delayed ultrasonic echo signal d_in[i-1] corresponding to the moment enable signal 1, obtaining... Figure 10 The trough signal is shown in (10f). That is, in Figure 10 In the application scenario shown, under the condition of the second enable signal output, only the trough signal is extracted.

[0096] It should be pointed out that, in Figure 6 and Figure 10 In the application scenario shown, the first symbol has a value of 1 and the second symbol has a value of 0. It can be understood that if the first symbol has a value of 0 and the second symbol has a value of 1, then under the condition that other conditions remain unchanged, the final extracted peak signal will also be reversed (the peak signal and the trough signal are reversed). For the sake of simplicity, this will not be elaborated here.

[0097] Third enable signal output condition:

[0098] The symbol signal sign[i] is the first symbol and the delayed signal sign[i-1] is the second symbol, and the symbol signal sign[i] is the second symbol and the delayed signal sign[i-1] is the first symbol.

[0099] Understandably, the third enable signal output condition combines the first enable signal output condition with the second enable signal output condition, and simultaneously extracts the peak signal and the trough signal.

[0100] For example, in Figure 12 In the application scenario shown, the ultrasonic echo signal d_in[i] is used as the minuend, and the delayed ultrasonic echo signal d_in[i-1] is used as the subtrahend; the first sign value is 1, and the second sign value is 0. Correspondingly, the third enable signal output condition is: when sign[i] = 1 and sign[i-1] = 0, and when sign[i] = 0 and sign[i-1] = 1, enable signal 1 is output, i.e., enable signal A. In subsequent steps, the peak output circuit 305 outputs the delayed ultrasonic echo signal d_in[i-1] corresponding to the moment enable signal 1, obtaining... Figure 12 The peak signal is shown in (12f). That is, in Figure 12 In the application scenario shown, under the condition of the third enable signal output, the peak signal and the trough signal are extracted simultaneously.

[0101] For example, in Figure 13 In the application scenario shown, the delayed ultrasonic echo signal d_in[i-1] is used as the minuend, and the ultrasonic echo signal d_in[i] is used as the subtrahend; the first sign value is 1, and the second sign value is 0. Correspondingly, the third enable signal output condition is: when sign[i] = 1 and sign[i-1] = 0; or sign[i] = 0 and sign[i-1] = 1, enable signal 1 is output, i.e., enable signal A. In subsequent steps, the peak output circuit 305 outputs the delayed ultrasonic echo signal d_in[i-1] corresponding to the moment enable signal 1, obtaining... Figure 13 The peak signal is shown in (13f). That is, in Figure 13 In the application scenario shown, under the condition of the third enable signal output, the peak signal and the trough signal are extracted simultaneously.

[0102] In the example above, the delayed signal d_in[i-1] of the ultrasonic echo signal is used as the peak signal. As mentioned above, the ultrasonic echo signal d_in[i] can also be used as the peak signal.

[0103] The signal input terminal of the peak output circuit 305 receives the ultrasonic echo signal d_in[i] or the delayed signal d_in[i-1] of the ultrasonic echo signal output from the second signal output terminal of the differential circuit 301. The control terminal of the peak output circuit 305 receives the enable signal A or enable signal B output from the signal output terminal of the logic operation circuit 304. Specifically, when the control terminal of the peak output circuit 305 receives the enable signal A from the signal output terminal of the logic operation circuit 304, the peak output circuit 305 outputs the signal corresponding to the ultrasonic echo signal d_in[i] or the delayed signal d_in[i-1] of the ultrasonic echo signal; this signal is the peak signal. In other words, the moment the enable signal A is generated is the moment corresponding to the peak signal in the ultrasonic echo signal d_in[i] or the delayed signal d_in[i-1].

[0104] For example, the peak signal output by the peak output circuit 305 is a wave peak signal, such as... Figure 14 As shown; the peak signal output by the peak output circuit 305 is a trough signal, such as... Figure 15 As shown.

[0105] In one possible implementation, to facilitate logical processing and decision-making in subsequent modules and improve the accuracy and reliability of system operation, when the peak output circuit 305 receives the enable signal B, it maintains the peak signal corresponding to the previous enable signal A, so that the peak output circuit 305 outputs the envelope curve of the peak signal. It should be noted that the enable signal B can be a signal such as 0, a certain voltage value, or it can be that no signal is emitted.

[0106] For example, in Figure 16 In this embodiment, the peak output circuit 305 outputs a peak signal when it receives enable signal A, and maintains the peak signal corresponding to the previous enable signal A when it receives enable signal B, thus forming the envelope curve of the peak signal. Similarly, the envelope curve of the trough signal can also be formed, which will not be described in detail here. It should be noted that in this embodiment, the peak output circuit 305 directly outputs the envelope curve of the peak signal. In some possible implementations, an envelope curve generation circuit can also be set in the echo signal processing circuit to generate the envelope curve corresponding to the peak signal, which will be described in detail below.

[0107] Please continue reading. Figure 3AThe threshold comparison circuit 306 receives the peak signal output by the peak output circuit 305 at its signal input terminal. The threshold comparison circuit 306 compares the peak signal with a peak signal threshold and outputs a comparison result. This comparison result is used to determine whether a valid echo signal has been received. For ease of explanation, the comparison result where the peak signal is greater than or equal to the peak signal threshold is referred to as the "first comparison result"; the comparison result where the peak signal is less than the peak signal threshold is referred to as the "second comparison result". In this embodiment, a valid echo signal determination rule can be set. Only when the first comparison result meets the valid echo signal determination rule is a valid echo signal determined to have been received, thus avoiding misjudgment. This valid echo signal is used to determine the distance to the obstacle.

[0108] In specific implementation, the valid echo signal determination rule is as follows: when the number of peak signals greater than or equal to the peak signal threshold meets a preset number, or when the duration of peak signals greater than or equal to the peak signal threshold meets a preset duration, a valid echo signal is determined to have been received, and a feedback signal is generated. This feedback signal is used to characterize the receipt of a valid echo signal. It can be understood that this valid echo signal determination rule can eliminate the influence of sudden noise or other interference signals, improving the reliability of the system. If the output is a discrete value of the peak signal, when comparing the peak signal with the peak signal threshold, the output signal will flip when the peak signal is greater than the peak signal threshold. The number of signal flips is calculated to see if it meets the preset number, such as 4, 5, or even more (or less). If it meets the preset number, it is determined that a valid echo signal has been received. If the output is a peak envelope curve, when comparing it with the peak signal threshold, the previous peak data will be maintained until the next peak signal appears. Therefore, the flipped signal is a continuous time. In particular, the vibration waveform of the ultrasonic signal is a process from low to high and then back to low. Therefore, when the first peak signal is greater than the peak signal threshold, the signal flip will continue until the peak signal is less than the peak signal threshold. Therefore, it is possible to determine whether the duration of the output signal meets the preset duration to determine whether a valid echo signal has been received.

[0109] It is understandable that ultrasonic signals attenuate during propagation; that is, the longer the propagation distance (the longer the propagation time), the weaker the ultrasonic signal intensity. Therefore, setting a fixed peak signal threshold may lead to misjudgment. To more accurately determine the valid echo signal, one possible implementation is to set the peak signal threshold to a value that dynamically changes with the propagation time of the ultrasonic signal. In other words, the peak signal threshold is related to the propagation time of the ultrasonic signal. In a specific implementation, a first timer can be set in the echo signal processing circuit of the ultrasonic sensor. This first timer starts counting after the ultrasonic signal is emitted. The peak signal threshold input to the threshold comparison circuit 306 is time-related, i.e., related to the time of the first timer. Alternatively, a first timer can be omitted. The peak signal threshold is time-related, and when it is stored in a memory or register, it is already a time-related peak signal threshold. The threshold comparison circuit 306 can then read the corresponding peak signal threshold from the storage module according to the clock.

[0110] See Figure 3B This is a block diagram of the echo signal processing circuit of another ultrasonic sensor provided in an embodiment of this application. Figure 3B and Figure 3A The difference is that the echo signal processing circuit also includes an envelope curve generation circuit 307 and a judgment circuit 308.

[0111] The envelope curve generation circuit 307 is electrically connected to the signal output of the peak output circuit 305, and its signal output is electrically connected to the signal input of the threshold comparison circuit 306. The envelope curve generation circuit 307 forms a continuous envelope curve from the peak signal and inputs it to the threshold comparison circuit 306. The threshold comparison circuit 306 compares the peak signal with a peak signal threshold and outputs the comparison result. The signal output of the threshold comparison circuit 306 is electrically connected to the signal input of the judgment circuit 308, which determines whether a valid echo signal has been received based on the comparison result output by the threshold comparison circuit 306. As mentioned above, the comparison result where the peak signal is greater than or equal to the peak signal threshold is called the "first comparison result"; the comparison result where the peak signal is less than the peak signal threshold is called the "second comparison result". In this embodiment, a valid echo signal determination rule can be set. Only when the first comparison result meets the valid echo signal determination rule is a valid echo signal determined to have been received, thus avoiding misjudgment. This valid echo signal is used to determine the distance to the obstacle.

[0112] In specific implementation, the valid echo signal determination rule is as follows: when the number of peak signals greater than or equal to the peak signal threshold meets a preset number, or when the duration of peak signals greater than or equal to the peak signal threshold meets a preset duration, a valid echo signal is determined to have been received, and a feedback signal is generated. This feedback signal is used to characterize the receipt of a valid echo signal. It can be understood that this valid echo signal determination rule can eliminate the influence of sudden noise or other interference signals, improving the reliability of the system.

[0113] In one possible implementation, the envelope curve generation circuit 307 is used to maintain the output value of the envelope curve at the previous peak signal before the next peak signal appears, under the first enable signal output condition or the second enable signal output condition. Specifically, the peak output circuit 305 can be a register, latch, storage unit circuit, etc., and can store the ultrasonic echo signal at a certain moment. For example, it can store the ultrasonic echo signal at the moment corresponding to the peak (store peak signal), and / or store the ultrasonic echo signal at the moment corresponding to the trough (store trough signal). The envelope curve generation circuit 307 can read the peak signal or trough signal stored in the peak output circuit 305, and maintain the output of the peak signal or trough signal before the next peak signal or trough signal appears, thus forming the envelope curve of the peak signal or trough signal.

[0114] For example, in Figure 16 In this embodiment, the peak output circuit 305 stores the peak signal upon receiving the enable signal A. The envelope curve generation circuit 307 can read the peak signal stored in the peak output circuit 305 and maintain the output of the peak signal until the next peak signal appears, thus forming a continuous envelope curve. Similarly, the envelope curve of the trough signal can also be formed, which will not be described in detail here.

[0115] In one possible implementation, to obtain a larger peak signal amplitude and make the peak signal more prominent, the envelope curve generation circuit 307 is further used to, when the third enable signal is output, use the difference between adjacent peak signals as the output value of the envelope curve to obtain a superimposed peak signal. Specifically, the peak output circuit 305 can store the peak and trough signals, and the envelope curve generation circuit 307 can read the peak and trough signals stored in the peak output circuit 305, performing addition or subtraction operations on adjacent peak and trough signals to obtain the superimposed peak signal. For example, if the peak signal of an adjacent group is 5V and the trough signal is -5V, after taking the absolute values ​​of the peak and trough signals of the adjacent group and performing addition, the superimposed peak signal obtained is |5V| + |-5V| = 10V. Alternatively, subtracting the trough signal from the peak signal yields a superimposed peak signal of (5V) - (-5V) = 10V.

[0116] In one possible implementation, in order to facilitate the logical processing and decision-making of subsequent modules and improve the accuracy and reliability of system operation, the envelope curve generation circuit 307, after obtaining the superimposed peak signals, can also maintain the difference of the previous set of peak signals before the difference of the next set of peak signals appears, so as to obtain the envelope curve of the superimposed peak signals.

[0117] For example, in Figure 17 In the process, when the peak output circuit 305 receives the enable signal A, it simultaneously extracts the peak and trough signals. The envelope curve generation circuit 307 uses the difference between adjacent peak signals as the output value of the envelope curve, and maintains the difference between the previous peak signals until the difference between the next set of peak signals appears, thus obtaining the envelope curve of the superimposed peak signals. It can be understood that in... Figure 17 In the implementation shown, the envelope curve has a larger amplitude and more obvious characteristics, which can further improve the accuracy and reliability of the system operation.

[0118] It should be noted that in some possible implementations, the judgment circuit 308 can also be located in a microprocessor chip electrically connected to the echo signal processing circuit. For example, in Figure 3A In the implementation shown, there is no judgment circuit 308 in the echo signal processing circuit. The comparison result between the peak signal output by the echo signal processing circuit and the peak signal threshold is used by the judgment circuit 308 in the microprocessor chip to determine whether a valid echo signal has been received and generate a feedback signal. Figure 3B For further details regarding the illustrated embodiments, please refer to [link / reference needed]. Figure 3A The description of the embodiments shown is omitted here for the sake of brevity.

[0119] Corresponding to the above embodiments, this application also provides a method for processing echo signals of an ultrasonic sensor.

[0120] See Figure 18 This is a schematic flowchart illustrating an echo signal processing method for an ultrasonic sensor provided in an embodiment of this application. Figure 18 As shown, it mainly includes the following steps.

[0121] Step S1801: Delay the received ultrasonic echo signal d_in[i] by a first time to obtain the delayed signal d_in[i-1] of the ultrasonic echo signal;

[0122] Step S1802: Calculate the difference between the ultrasonic echo signal d_in[i] and the delayed signal d_in[i-1] of the ultrasonic echo signal to obtain the differential signal diff[i].

[0123] Step S1803: Mark the part of the differential signal diff[i] that is greater than 0 as the first symbol, and mark the part of the differential signal diff[i] that is less than 0 as the second symbol, to obtain the symbol signal sign[i] corresponding to the differential signal diff[i].

[0124] Step S1804: Delay the symbol signal sign[i] by a second time to obtain the delayed signal sign[i-1] of the symbol signal;

[0125] Step S1805: When the symbol signal sign[i] and the delayed signal sign[i-1] are different and the enable signal output condition is met, output enable signal A;

[0126] Step S1806: Output peak signal, which is the signal corresponding to the ultrasonic echo signal d_in[i] or the delayed signal d_in[i-1] of the ultrasonic echo signal when the enable signal A is received;

[0127] Step S1807: Compare the peak signal with the peak signal threshold and output the comparison result. The comparison result is used to determine that a valid echo signal has been received when the first comparison result meets the valid echo signal determination rule. The first comparison result is the comparison result where the peak signal is greater than or equal to the peak signal threshold. The valid echo signal is used to determine the distance to the obstacle.

[0128] In one possible implementation, the enable signal output condition is a first enable signal output condition, a second enable signal output condition, or a third enable signal output condition, wherein: the first enable signal output condition is: the symbol signal sign[i] is the second symbol and the delayed signal sign[i-1] of the symbol signal is the first symbol; or, the second enable signal output condition is: the symbol signal sign[i] is the first symbol and the delayed signal sign[i-1] of the symbol signal is the second symbol; or, the third enable signal output condition is: the symbol signal sign[i] is the second symbol and the delayed signal sign[i-1] of the symbol signal is the first symbol, and the symbol signal sign[i] is the first symbol and the delayed signal sign[i-1] of the symbol signal is the second symbol.

[0129] In one possible implementation, the output peak signal is converted into an envelope curve before a peak signal threshold comparison is performed.

[0130] In one possible implementation, when the first enable signal output condition or the second enable signal output condition is met, the output value of the envelope curve maintains the previous peak signal until the next peak signal appears.

[0131] In one possible implementation, when the third enable signal is output, the difference between the peak signals of adjacent sets is used as the output value of the envelope curve.

[0132] In one possible implementation, the output value of the envelope curve maintains the difference of the previous set of peak signals until the difference of the next set of peak signals appears.

[0133] In one possible implementation, an enable signal B is output when the first enable signal output condition or the second enable signal output condition is not met; when enable signal B is received, the peak signal corresponding to the previous enable signal A is maintained.

[0134] In one possible implementation, the first time and the second time are the same, or the first time and the second time are both one clock cycle.

[0135] In one possible implementation, it is determined whether the first comparison result meets the valid echo signal determination rule. The valid echo signal determination rule is: when the number of peak signals greater than or equal to the peak signal threshold meets the preset number, or when the duration of the peak signals greater than or equal to the peak signal threshold meets the preset duration, it is determined that a valid echo signal has been received and a feedback signal is generated.

[0136] 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.

[0137] Corresponding to the above embodiments, this application also provides an ultrasonic sensor chip, which includes:

[0138] The differential circuit includes a first delay circuit and a difference calculation circuit. The signal output terminal of the first delay circuit is electrically connected to the first signal input terminal of the difference calculation circuit, and the signal input terminal of the first delay circuit is electrically connected to the second signal input terminal of the difference calculation circuit. The first delay circuit is used to delay the received ultrasonic echo signal d_in[i] by a first time to obtain the delayed signal d_in[i-1] of the ultrasonic echo signal. The difference calculation circuit is used to perform difference calculation between the ultrasonic echo signal d_in[i] and the delayed signal d_in[i-1] of the ultrasonic echo signal to obtain the differential signal diff[i].

[0139] The symbol extraction circuit is electrically connected to the first signal output terminal of the differential circuit. The symbol extraction circuit is used to mark the part of the differential signal diff[i] that is greater than 0 as the first symbol and mark the part of the differential signal diff[i] that is less than 0 as the second symbol, so as to obtain the symbol signal sign[i] corresponding to the differential signal diff[i].

[0140] The second delay circuit is electrically connected to the signal output of the symbol extraction circuit. The second delay circuit is used to delay the symbol signal sign[i] by a second time to obtain the delayed signal sign[i-1] of the symbol signal.

[0141] The logic operation circuit has its first signal input terminal electrically connected to the signal output terminal of the symbol extraction circuit, and its second signal input terminal electrically connected to the signal output terminal of the second delay circuit. The logic operation circuit is used to output the enable signal A when the symbol signal sign[i] and the delayed signal sign[i-1] of the symbol signal are different and the enable signal output condition is met.

[0142] The peak output circuit is electrically connected to the second signal output terminal of the differential circuit, and the control terminal of the peak output circuit is electrically connected to the signal output terminal of the logic operation circuit. The peak output circuit is used to output the peak signal, which is the signal corresponding to the ultrasonic echo signal d_in[i] or the delayed signal d_in[i-1] of the ultrasonic echo signal when the enable signal A is received.

[0143] A threshold comparison circuit is included, with its signal input terminal electrically connected to the signal output terminal of the peak output circuit. The threshold comparison circuit is used to compare the peak signal with a peak signal threshold and output a comparison result. The comparison result is used to determine that a valid echo signal has been received when the first comparison result meets the valid echo signal determination rule. The first comparison result is the comparison result where the peak signal is greater than or equal to the peak signal threshold. The valid echo signal is used to determine the distance to the obstacle.

[0144] In one possible implementation, the enable signal output condition is a first enable signal output condition, a second enable signal output condition, or a third enable signal output condition, wherein: the first enable signal output condition is: the symbol signal sign[i] is the second symbol and the delayed signal sign[i-1] of the symbol signal is the first symbol; or, the second enable signal output condition is: the symbol signal sign[i] is the first symbol and the delayed signal sign[i-1] of the symbol signal is the second symbol; or, the third enable signal output condition is: the symbol signal sign[i] is the second symbol and the delayed signal sign[i-1] of the symbol signal is the first symbol, and when the symbol signal sign[i] is the first symbol and the delayed signal sign[i-1] of the symbol signal is the second symbol.

[0145] In one possible implementation, an envelope curve generation circuit is also included. The signal input terminal of the envelope curve generation circuit is electrically connected to the signal output terminal of the peak output circuit, and the signal output terminal of the envelope curve generation circuit is electrically connected to the signal input terminal of the threshold comparison circuit. The envelope curve generation circuit is used to form a continuous envelope curve from the peak signal and input it to the threshold comparison circuit.

[0146] In one possible implementation, the envelope curve generation circuit is used to maintain the output value of the envelope curve at the previous peak signal before the next peak signal appears, under the first enable signal output condition or the second enable signal output condition.

[0147] In one possible implementation, the envelope curve generation circuit is used to take the difference between the peak signals of adjacent groups as the output value of the envelope curve when the third enable signal is output.

[0148] In one possible implementation, the envelope curve generation circuit is also used to maintain the output value of the envelope curve at the difference of the previous set of peak signals until the difference of the next set of peak signals appears.

[0149] In one possible implementation, the logic operation circuit is further configured to output an enable signal B when the first enable signal output condition or the second enable signal output condition is not met; the peak output circuit is further configured to maintain the peak signal corresponding to the previous enable signal A when the enable signal B is received.

[0150] In one possible implementation, a judgment circuit is also included. The judgment circuit is used to determine whether the first comparison result meets the valid echo signal determination rule. The valid echo signal determination rule is: when the number of peak signals greater than or equal to the peak signal threshold meets the preset number, or when the duration of the peak signals greater than or equal to the peak signal threshold meets the preset duration, it is determined that a valid echo signal has been received and a feedback signal is generated.

[0151] In one possible implementation, the system further includes: a storage circuit storing the peak signal threshold, the peak signal threshold being time-dependent; and a threshold comparison circuit electrically connected to the storage circuit to read the peak signal threshold.

[0152] In one possible implementation, it further includes: a driving circuit for generating an ultrasonic excitation signal after receiving a trigger signal, the ultrasonic excitation signal being used to drive the ultrasonic sensor to emit ultrasonic signals.

[0153] 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.

[0154] Corresponding to the above embodiments, this application also provides an ultrasonic radar device.

[0155] See Figure 19 This is a structural block diagram of an ultrasonic radar device provided in an embodiment of this application. Figure 19 As shown, the ultrasonic radar device includes: an ultrasonic sensor chip; and an ultrasonic sensor for emitting ultrasonic signals according to ultrasonic excitation signals and receiving ultrasonic echo signals d_in[i]. The specific details of the ultrasonic sensor chip can be found in the description of the above embodiments, and will not be repeated here for the sake of brevity.

[0156] See Figure 20 This is a structural block diagram of another ultrasonic radar device provided in an embodiment of this application. Figure 20 As shown, in Figure 19 Based on the embodiment shown, the ultrasonic radar device further includes: a microprocessor chip electrically connected to an ultrasonic sensor chip, used to send a trigger signal; the ultrasonic sensor chip receives the trigger signal and generates an ultrasonic excitation signal; the microprocessor chip is also used to calculate the obstacle distance based on the feedback signal sent by the ultrasonic sensor chip indicating that a valid echo signal has been received.

[0157] In one possible implementation, the microprocessor chip includes a second timer, which starts timing after a trigger signal is sent and stops timing when a feedback signal is received; specifically, the microprocessor chip is used to receive the feedback signal and calculate the obstacle distance based on the feedback signal and the timing duration of the second timer.

[0158] In one possible implementation, the microprocessor chip is further configured to trigger the prompting system to output prompt information based on the obstacle distance. Specifically, this prompt information can be voice information, light information, or display information, etc. This application embodiment does not impose specific limitations on the type of prompt information. It is understood that, to facilitate user differentiation of obstacle distances, different prompt information will be provided for different obstacle distances.

[0159] 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.

[0160] 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.

[0161] 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.

[0162] 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.

[0163] 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.

[0164] 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.

[0165] 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.

[0166] 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 echo signal processing circuit for an ultrasonic sensor, characterized in that, include: A differential circuit, comprising a first delay circuit and a difference calculation circuit, wherein the first delay circuit is used to delay the received ultrasonic echo signal d_in[i] by a first time to obtain a delayed signal d_in[i-1] of the ultrasonic echo signal; and the difference calculation circuit is used to perform difference calculation between the ultrasonic echo signal d_in[i] and the delayed signal d_in[i-1] of the ultrasonic echo signal to obtain a differential signal diff[i]. A symbol extraction circuit is used to mark the part of the differential signal diff[i] that is greater than 0 as a first symbol and mark the part of the differential signal diff[i] that is less than 0 as a second symbol, so as to obtain the symbol signal sign[i] corresponding to the differential signal diff[i]. The second delay circuit is used to delay the symbol signal sign[i] by a second time to obtain the delayed signal sign[i-1] of the symbol signal; A logic operation circuit is used to output an enable signal A when the symbol signal sign[i] and the delayed signal sign[i-1] of the symbol signal are different and the enable signal output condition is met; A peak output circuit is used to output a peak signal, wherein the peak signal is the signal corresponding to the ultrasonic echo signal d_in[i] or the delayed signal d_in[i-1] of the ultrasonic echo signal when the enable signal A is received; A threshold comparison circuit is used to compare the peak signal with a peak signal threshold and output a comparison result. The comparison result is used to: determine that a valid echo signal has been received when the first comparison result meets the valid echo signal determination rule. The first comparison result is the comparison result that the peak signal is greater than or equal to the peak signal threshold. The valid echo signal is used to determine the distance to the obstacle.

2. The echo signal processing circuit of the ultrasonic sensor according to claim 1, characterized in that, The enable signal output condition is a first enable signal output condition, a second enable signal output condition, or a third enable signal output condition, wherein: The first enable signal output condition is: the symbol signal sign[i] is the second symbol and the delayed signal sign[i-1] of the symbol signal is the first symbol; or, The second enable signal output condition is: the symbol signal sign[i] is the first symbol and the delayed signal sign[i-1] of the symbol signal is the second symbol; or, The third enable signal output condition is: the symbol signal sign[i] is the second symbol and the delayed signal sign[i-1] of the symbol signal is the first symbol, and the symbol signal sign[i] is the first symbol and the delayed signal sign[i-1] of the symbol signal is the second symbol.

3. The echo signal processing circuit of the ultrasonic sensor according to claim 2, characterized in that, It also includes an envelope curve generation circuit, used to form a continuous envelope curve from the peak signal and input it to the threshold comparison circuit.

4. The echo signal processing circuit of the ultrasonic sensor according to claim 3, characterized in that, The envelope curve generation circuit is used to maintain the output value of the envelope curve at the previous peak signal before the next peak signal appears, under the first enable signal output condition or the second enable signal output condition.

5. The echo signal processing circuit of the ultrasonic sensor according to claim 3, characterized in that, The envelope curve generation circuit is used to, when the third enable signal is output, use the difference between the peak signals of an adjacent group as the output value of the envelope curve.

6. The echo signal processing circuit of the ultrasonic sensor according to claim 5, characterized in that, The envelope curve generation circuit is also used to maintain the output value of the envelope curve at the difference of the previous set of peak signals until the difference of the next set of peak signals appears.

7. The echo signal processing circuit of the ultrasonic sensor according to claim 2, characterized in that, The logic operation circuit is also used to output an enable signal B when the first enable signal output condition or the second enable signal output condition is not met. The peak output circuit is further configured to maintain the peak signal corresponding to the previous enable signal A when the enable signal B is received.

8. The echo signal processing circuit of the ultrasonic sensor according to claim 1, characterized in that, The first time and the second time are the same, or the first time and the second time are both one clock cycle.

9. The echo signal processing circuit of the ultrasonic sensor according to any one of claims 1-8, characterized in that, It also includes a judgment circuit, which is used to determine whether the first comparison result meets the valid echo signal determination rule. The valid echo signal determination rule is: when the number of peak signals greater than or equal to the peak signal threshold meets the preset number, or when the duration of the peak signals greater than or equal to the peak signal threshold meets the preset duration, it is determined that a valid echo signal has been received and a feedback signal is generated.

10. A method for processing echo signals from an ultrasonic sensor, characterized in that, include: The received ultrasonic echo signal d_in[i] is delayed by a first time to obtain the delayed signal d_in[i-1] of the ultrasonic echo signal; The difference between the ultrasonic echo signal d_in[i] and the delayed signal d_in[i-1] of the ultrasonic echo signal is calculated to obtain the differential signal diff[i]. The portion of the differential signal diff[i] that is greater than 0 is marked as the first symbol, and the portion of the differential signal diff[i] that is less than 0 is marked as the second symbol, thereby obtaining the symbol signal sign[i] corresponding to the differential signal diff[i]. The symbol signal sign[i] is delayed by a second time to obtain the delayed signal sign[i-1] of the symbol signal; When the symbol signal sign[i] and the delayed signal sign[i-1] of the symbol signal are different and the enable signal output condition is met, the enable signal A is output; Output a peak signal, which is the signal corresponding to the ultrasonic echo signal d_in[i] or the delayed signal d_in[i-1] of the ultrasonic echo signal when the enable signal A is received; The peak signal is compared with the peak signal threshold and the comparison result is output. The comparison result is used to: determine that a valid echo signal has been received when the first comparison result meets the valid echo signal determination rule. The first comparison result is the comparison result that the peak signal is greater than or equal to the peak signal threshold. The valid echo signal is used to determine the distance to the obstacle.

11. The echo signal processing method of the ultrasonic sensor according to claim 10, characterized in that, The enable signal output condition is a first enable signal output condition, a second enable signal output condition, or a third enable signal output condition, wherein: The first enable signal output condition is: the symbol signal sign[i] is the second symbol and the delayed signal sign[i-1] of the symbol signal is the first symbol; or, The second enable signal output condition is: the symbol signal sign[i] is the first symbol and the delayed signal sign[i-1] of the symbol signal is the second symbol; or, The third enable signal output condition is: the symbol signal sign[i] is the second symbol and the delayed signal sign[i-1] of the symbol signal is the first symbol, and the symbol signal sign[i] is the first symbol and the delayed signal sign[i-1] of the symbol signal is the second symbol.

12. The echo signal processing method of the ultrasonic sensor according to claim 11, characterized in that, The output peak signal is converted into an envelope curve before a peak signal threshold comparison is performed.

13. The echo signal processing method of the ultrasonic sensor according to claim 12, characterized in that, When the first enable signal output condition or the second enable signal output condition is met, the output value of the envelope curve remains at the previous peak signal until the next peak signal appears.

14. The echo signal processing method of the ultrasonic sensor according to claim 12, characterized in that, When the third enable signal is output, the difference between the peak signals of adjacent groups is used as the output value of the envelope curve.

15. The echo signal processing method of the ultrasonic sensor according to claim 14, characterized in that, The output value of the envelope curve remains at the difference of the previous set of peak signals until the difference of the next set of peak signals appears.

16. The echo signal processing method of the ultrasonic sensor according to claim 11, characterized in that, When the first enable signal output condition or the second enable signal output condition is not met, enable signal B is output; when enable signal B is received, the peak signal corresponding to the previous enable signal A is maintained.

17. The echo signal processing method of the ultrasonic sensor according to claim 11, characterized in that, The first time and the second time are the same, or the first time and the second time are both one clock cycle.

18. The echo signal processing method of the ultrasonic sensor according to any one of claims 10-17, characterized in that, Determine whether the first comparison result meets the valid echo signal determination rule. The valid echo signal determination rule is: when the number of peak signals greater than or equal to the peak signal threshold meets the preset number, or when the duration of the peak signal greater than or equal to the peak signal threshold meets the preset duration, it is determined that a valid echo signal has been received and a feedback signal is generated.

19. An ultrasonic sensor chip, characterized in that, include: A differential circuit includes a first delay circuit and a difference calculation circuit. The signal output terminal of the first delay circuit is electrically connected to the first signal input terminal of the difference calculation circuit, and the signal input terminal of the first delay circuit is electrically connected to the second signal input terminal of the difference calculation circuit. The first delay circuit is used to delay the received ultrasonic echo signal d_in[i] by a first time to obtain the delayed signal d_in[i-1] of the ultrasonic echo signal. The difference calculation circuit is used to perform difference calculation between the ultrasonic echo signal d_in[i] and the delayed signal d_in[i-1] of the ultrasonic echo signal to obtain the differential signal diff[i]. A symbol extraction circuit is provided, wherein the signal input terminal of the symbol extraction circuit is electrically connected to the first signal output terminal of the differential circuit. The symbol extraction circuit is used to mark the part of the differential signal diff[i] that is greater than 0 as the first symbol and mark the part of the differential signal diff[i] that is less than 0 as the second symbol, thereby obtaining the symbol signal sign[i] corresponding to the differential signal diff[i]. The second delay circuit is electrically connected to the signal output of the symbol extraction circuit. The second delay circuit is used to delay the symbol signal sign[i] by a second time to obtain the delayed signal sign[i-1] of the symbol signal. A logic operation circuit, wherein the first signal input terminal of the logic operation circuit is electrically connected to the signal output terminal of the symbol extraction circuit, and the second signal input terminal of the logic operation circuit is electrically connected to the signal output terminal of the second delay circuit. The logic operation circuit is used to output an enable signal A when the symbol signal sign[i] and the delay signal sign[i-1] of the symbol signal are different and the enable signal output condition is met. A peak output circuit, wherein the signal input terminal of the peak output circuit is electrically connected to the second signal output terminal of the differential circuit, and the control terminal of the peak output circuit is electrically connected to the signal output terminal of the logic operation circuit, the peak output circuit is used to output a peak signal, wherein the peak signal is the signal corresponding to the ultrasonic echo signal d_in[i] or the delayed signal d_in[i-1] of the ultrasonic echo signal when the enable signal A is received; A threshold comparison circuit is provided, wherein the signal input terminal of the threshold comparison circuit is electrically connected to the signal output terminal of the peak output circuit. The threshold comparison circuit is used to compare the peak signal with a peak signal threshold and output a comparison result. The comparison result is used to determine that a valid echo signal has been received when the first comparison result meets the valid echo signal determination rule. The first comparison result is the comparison result that the peak signal is greater than or equal to the peak signal threshold. The valid echo signal is used to determine the distance to the obstacle.

20. The ultrasonic sensor chip according to claim 19, characterized in that, The enable signal output condition is a first enable signal output condition, a second enable signal output condition, or a third enable signal output condition, wherein: The first enable signal output condition is: the symbol signal sign[i] is the second symbol and the delayed signal sign[i-1] of the symbol signal is the first symbol; or, The second enable signal output condition is: the symbol signal sign[i] is the first symbol and the delayed signal sign[i-1] of the symbol signal is the second symbol; or, The third enable signal output condition is: the symbol signal sign[i] is the second symbol and the delayed signal sign[i-1] of the symbol signal is the first symbol, and the symbol signal sign[i-1] is the second symbol.

21. The ultrasonic sensor chip according to claim 20, characterized in that, It also includes an envelope curve generation circuit, the signal input terminal of which is electrically connected to the signal output terminal of the peak output circuit, and the signal output terminal of which is electrically connected to the signal input terminal of the threshold comparison circuit. The envelope curve generation circuit is used to form a continuous envelope curve from the peak signal and input it to the threshold comparison circuit.

22. The ultrasonic sensor chip according to claim 21, characterized in that, The envelope curve generation circuit is used to maintain the output value of the envelope curve at the previous peak signal before the next peak signal appears, under the first enable signal output condition or the second enable signal output condition.

23. The ultrasonic sensor chip according to claim 21, characterized in that, The envelope curve generation circuit is used to, when the third enable signal is output, use the difference between the peak signals of an adjacent group as the output value of the envelope curve.

24. The ultrasonic sensor chip according to claim 23, characterized in that, The envelope curve generation circuit is also used to maintain the output value of the envelope curve at the difference of the previous set of peak signals until the difference of the next set of peak signals appears.

25. The ultrasonic sensor chip according to claim 21, characterized in that, The logic operation circuit is also used to output an enable signal B when the first enable signal output condition or the second enable signal output condition is not met. The peak output circuit is also used to maintain the peak signal corresponding to the previous enable signal A when the enable signal B is received.

26. The ultrasonic sensor chip according to any one of claims 19-25, characterized in that, It also includes a judgment circuit, which is used to determine whether the first comparison result meets the valid echo signal determination rule. The valid echo signal determination rule is: when the number of peak signals greater than or equal to the peak signal threshold meets the preset number, or when the duration of the peak signals greater than or equal to the peak signal threshold meets the preset duration, it is determined that a valid echo signal has been received and a feedback signal is generated.

27. The ultrasonic sensor chip according to any one of claims 19-25, characterized in that, Also includes: It also includes a storage circuit that stores the peak signal threshold, the peak signal threshold being time-dependent; The threshold comparison circuit is electrically connected to the storage circuit to read the peak signal threshold.

28. The ultrasonic sensor chip according to any one of claims 19-25, characterized in that, Also includes: A driving circuit is used to generate an ultrasonic excitation signal after receiving a trigger signal, the ultrasonic excitation signal being used to drive the ultrasonic sensor to emit ultrasonic signals.

29. An ultrasonic radar device, characterized in that, include: The ultrasonic sensor chip according to any one of claims 19-28; An ultrasonic sensor is used to emit ultrasonic signals based on ultrasonic excitation signals and to receive ultrasonic echo signals d_in[i].

30. The ultrasonic radar device according to claim 29, characterized in that, Also includes: A microprocessor chip, electrically connected to the ultrasonic sensor chip, is used to send a trigger signal, and the ultrasonic sensor chip receives the trigger signal and generates the ultrasonic excitation signal; the microprocessor chip is also used to calculate the distance to the obstacle based on the feedback signal sent by the ultrasonic sensor chip indicating that a valid echo signal has been received.

31. The ultrasonic radar device according to claim 30, characterized in that, The microprocessor chip includes a timer, which is used to start timing after a trigger signal is sent and to stop timing when the feedback signal is received; The microprocessor chip is specifically used to receive the feedback signal and calculate the obstacle distance based on the feedback signal and the duration of the timer.

32. The ultrasonic radar device according to claim 30 or 31, characterized in that, The microprocessor chip is also used to trigger the prompting system to output prompt information based on the distance to the obstacle.

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