Ultrasound detection system and method

Abstract

The present invention discloses an ultrasound detection system and method. [Solution] The system includes a mixed wave generating circuit used for mixing and superimposing excitation waves of at least two different frequencies, an ultrasonic generating module used for generating ultrasonic signals with at least two different detection ranges, an associated calculation circuit module including at least two associated calculation circuits for performing correlation calculation between the amplified and filtered echo signals and the corresponding reference waves, and a CPU processing unit used for determining the distance information and the existence angle of the measured object based on the calculation results of the correlation degrees of the different detection ranges. In the embodiment of the present invention, by transmitting excitation waves with different frequencies to the same ultrasonic generating module, the ultrasonic detection system using only one ultrasonic generating module realizes the simultaneous detection of the distance and the existence angle of the object, and improves the stability of the ultrasonic detection process.

Description

[Technical Field]

[0001] FIELD OF THE INVENTION Embodiments of the present invention relate to the field of ultrasound detection, and more particularly to a mixed-wave based ultrasound detection system and method. [Background technology]

[0002] In the ultrasonic ranging principle, when an obstacle is detected by receiving reflected waves from an object using waves emitted by an "ultrasonic microphone," the distance to the obstacle can be determined, but it is not possible to determine from which position on a concentric circle centered on the "ultrasonic microphone" the distance is reflected, or the area and angle of the object's presence.In particular, when angle detection in the vertical direction is required, for example, when trying to distinguish whether the obstacle is an "opposing object" located directly in front or a "road object" located on the road surface, the error rate is significantly high.Many ultrasonic detection system products currently on the market are unable to accurately determine the "angle of presence" of an obstacle. Summary of the Invention [Problem to be solved by the invention]

[0003] The present invention provides an ultrasonic detection system and method, which does not require the use of multiple "microphones" or multiple ultrasonic sensors, but can simultaneously detect the distance and angle of an object using only one "microphone" or one ultrasonic sensor. [Means for solving the problem]

[0004] In a first aspect, embodiments of the present invention provide an ultrasound detection system, the ultrasound detection system comprising: It includes a mixed wave generating circuit, an ultrasonic wave generating module, an amplifying and filtering circuit module, a related calculation circuit module and a CPU processing unit; The mixed wave generating circuit is used to mix and superimpose excitation waves of at least two different frequencies and output the mixed and superimposed excitation waves to the ultrasound generating module, The ultrasonic wave generating module is used to generate ultrasonic signals having at least two different detection ranges based on the mixed and superimposed excitation waves; the amplification and filtering circuit module is used to perform amplification and filtering processing on the echo signals received by the ultrasound generation module; the associated calculation circuit module includes at least two associated calculation circuits, each of which is used to perform correlation calculation between the amplified and filtered echo signal and a corresponding reference wave, to obtain correlation calculation results for different detection ranges; The CPU processing unit includes a presence angle determination processing module, which is used to determine the distance information and presence angle of the measured object based on the calculation result of the correlation degree of different detection ranges.

[0005] Optionally, the CPU further includes an excitation wave generation processing module, which is used to generate excitation waves of at least two different frequencies.

[0006] Optionally, the CPU further includes a reference wave generation processing module, which is used to generate reference waves corresponding to the at least two ultrasonic signals having different detection ranges.

[0007] Optionally, the existence angle determination processing module specifically: Identifying the presence angle of the object to be measured based on the correlation calculation result and a pre-established correlation between the correlation value and the object presence angle; The detection time of the object to be measured is obtained based on the correlation peak value, and distance information of the object to be measured is calculated based on the detection time.

[0008] Optionally, establishing an association relationship between the correlation degree value and the object presence angle includes: Obtaining correlation values ​​between the ultrasonic echo signals and the reference wave corresponding to different detection angles; and establishing a correlation relationship between the correlation value and the object presence angle based on the detected angle and the corresponding correlation calculation result.

[0009] In a second aspect, an embodiment of the present invention further provides an ultrasonic detection method for the ultrasonic detection system according to any one of the preceding claims, the method comprising: Simultaneously transmitting at least two mixed excitation waves of different frequencies to a single ultrasonic generating module, so that the ultrasonic generating module correspondingly generates at least two ultrasonic signals with different detection ranges; receiving echo signals of an ultrasonic signal and calculating a correlation between each of the echo signals and a corresponding reference wave; and determining the angle of presence and distance information of the object to be measured based on the result of the correlation calculation.

[0010] Selectively specifying the existence angle and distance information of the object to be measured based on the correlation degree calculation result includes: Identifying the presence angle of the object to be measured based on the correlation calculation result and a pre-established correlation between the correlation value and the object presence angle; The method includes obtaining a detection time of the object to be measured based on the correlation peak value, and calculating distance information of the object to be measured based on the detection time.

[0011] Optionally, establishing an association relationship between the correlation degree value and the object presence angle includes: Obtaining correlation values ​​between the ultrasonic echo signals and the reference wave corresponding to different detection angles; and establishing a correlation relationship between the correlation value and the object presence angle based on the detected angle and the corresponding correlation calculation result. [Effects of the Invention]

[0012] In an embodiment of the present invention, ultrasonic signals with different detection ranges are generated by transmitting excitation waves of different frequencies to the same ultrasonic generating module, and the distance information and the presence angle of the measured object are determined based on the correlation value between the ultrasonic echo signal and the corresponding reference signal according to the pre-established correlation value and the object presence angle. In an ultrasonic detection system that does not require the use of multiple microphones or ultrasonic sensors, an ultrasonic detection system that uses only one microphone or one ultrasonic sensor can simultaneously detect the distance and the presence angle of the object, thereby improving the stability of the ultrasonic detection process. [Brief explanation of the drawings]

[0013] [Figure 1] FIG. 1 shows a configuration diagram of a conventional system. [Figure 2] 1 shows a schematic diagram of a chirp wave in a conventional example. [Figure 3] 1 shows a schematic diagram of a conventional correlation value calculation method. [Figure 4(1)] 10A and 10B are schematic diagrams illustrating object detection in the horizontal direction in a conventional example. [Figure 4(2)] 1 shows a schematic diagram of object detection in the vertical direction in a conventional example. [Figure 5(1)] 1 is a schematic diagram showing ultrasonic directional characteristics of Example 1 of the present invention. [Figure 5(2)] 1 is a schematic diagram showing ultrasonic impedance characteristics of Example 1 of the present invention. [Figure 5(3)] 1 is a schematic diagram showing the transmission and reception sensitivity of ultrasonic waves in Example 1 of the present invention. [Figure 6(1)] 1 is a schematic diagram showing a detection area range (after K correction) of a horizontal angle in Example 1 of the present invention. [Figure 6(2)] 1 is a schematic diagram showing a detection area range (after K correction) of a vertical angle in Example 1 of the present invention. [Figure 7] 1 shows a system configuration diagram of a first embodiment of the present invention. [Figure 8] 1 shows a schematic diagram of chirp wave mixing in Example 1 of the present invention. [Figure 9]1 shows a schematic diagram of a correlation value calculation method_object position 1 according to a first embodiment of the present invention. [Figure 10] 1 shows a schematic diagram of a correlation value calculation method_object position 2 according to the first embodiment of the present invention. [Figure 11] 1 shows a schematic diagram of a correlation value calculation method for object position 3 according to the first embodiment of the present invention. [Figure 12(1)] 10 shows a schematic diagram of the relationship between the correlation value calculation result Vout and the object position. [Figure 12(2)] 10 shows a schematic diagram of the relationship between the correlation value calculation result Vout and the object angle. [Figure 13(1)] 1 shows a schematic diagram of an application of determining a horizontal direction existence angle according to a first embodiment of the present invention. [Figure 13(2)] 1 shows a schematic diagram of an application of determining the vertical direction existence angle in Example 1 of the present invention. [Figure 14] FIG. 10 shows a system configuration diagram of a second embodiment of the present invention. [Figure 15] 10 is a schematic diagram showing a pulse wave mixing according to a second embodiment of the present invention. [Figure 16] 10 is a schematic diagram of a correlation value calculation method for object position 1 according to a second embodiment of the present invention. [Figure 17] 10 is a schematic diagram of a correlation value calculation method_object position 2 according to a second embodiment of the present invention. [Figure 18] 10 is a schematic diagram of a correlation value calculation method for object position 3 according to a second embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0014] The present invention will be described in more detail below in conjunction with the accompanying drawings and examples. It should be understood that the specific examples described herein are only used to interpret the present invention and are not intended to limit the present invention. It should also be noted that for the sake of convenience, the accompanying drawings only show parts relevant to the present invention, not the entire structure. To better understand the technical solutions of the embodiments of the present invention, we first introduce the ultrasonic detection methods commonly used in the prior art. As shown in Figure 1, the system configuration of an ultrasonic detection system in the prior art includes a chirp wave generating circuit, an ultrasonic wave generating module, an amplifying and filtering circuit, a related calculation circuit, and a CPU processing unit. (1) The chirp wave generating circuit generates chirp waves and drives the ultrasonic wave generating module to transmit ultrasonic waves. (2) The ultrasonic wave generating module transmits chirp-type ultrasonic waves. (3) The amplification and filtering circuit amplifies the received wave reflected from the object to obtain an amplification and filtering circuit output signal. (4) The related calculation circuit uses a device capable of high-speed calculation processing, such as a DSP, to perform related calculations on the "reference wave output" generated from the chirp wave. (5) The CPU processing unit controls and processes all relevant signals in the system, processes the results output from the relevant calculation circuits, determines the distance of the object, and outputs the detection result.

[0015] Figure 2 shows the attributes of a chirp wave in the prior art. The time difference between t0 and t1 is defined as the chirp wave transmission time, and the corresponding Fc1_0 - Fc1_1 is defined as the chirp wave frequency range. There are several types of chirp waves, such as a linear increase, linear decrease, or nonlinear increase or decrease in frequency over time. Figure 2 shows a chirp wave whose frequency increases linearly over time. After the chirp wave is generated, the ultrasonic generating module transmits chirp-type ultrasonic waves, receives the reflected wave from the object, and then enters the amplification and filtering circuit to obtain an output signal from the amplification and filtering circuit. Here, the time when the reflected signal from the object is received is defined as t2.

[0016] FIG. 3 shows a conventional method for calculating correlation values. First, the correlation value at time t0 is calculated as follows: "Reference wave_0000" is multiplied by "amplification filtering circuit output," the multiplication results are added, and the resulting sum is used as the correlation value at time t0, which is then stored as "calculation result of correlation value." Next, "reference wave_0001" is obtained by delaying one period, and "reference wave_0001" is multiplied by "amplification filtering circuit output," the multiplication results are added, and the resulting sum is used as the correlation value at time t1. This process is repeated sequentially. In other words, the correlation value calculation is equivalent to calculating the correlation between the two. Around t2, when a reflected wave from an object is present, the correlation value between the "reference wave" and "amplification filtering circuit output" becomes large, and the value of the "calculation result of correlation value" also becomes large.

[0017] After calculating the correlation values ​​at all times, the calculation results are evaluated using a threshold. If the correlation value calculation result is greater than the correlation threshold, it is considered that an obstacle has been detected, and the time t2 at which the peak correlation value appears is searched for. By converting the reception time into the distance to the object, the detected distance to the object can be calculated. While this conventional system can output the distance to the object, as shown in the horizontal angle detection diagram in Figure 4(1), it is unable to determine the position on the concentric circle centered on the "ultrasonic microphone" from which this distance is reflected, nor is it able to determine the object's location area and angle. To address this issue, the technical solution typically adopted in many ultrasonic inspection systems currently on the market combines multiple ultrasonic sensors and determines the object's location based on their respective results, which means that multiple ultrasonic sensors are required for area determination. However, many ultrasonic detection systems currently on the market are unable to accurately determine the object's location angle.

[0018] As shown in the vertical angle detection in Figure 4(2), in the vertical direction, the conventional system cannot distinguish whether a detected object is an "opposing object" located in the front direction or a "road object" located on the road surface. In the case of road objects, it should be possible to effectively detect and distinguish the direction of a large road object such as a road edge (stone curb), but it is necessary to avoid detecting small uneven objects on the road surface. Therefore, it is necessary to determine whether the object is an "opposing object" located in the front direction, a "road object" on the road surface, or simply a small uneven object on the road surface based on the object's angle of existence.

[0019] Based on the deficiencies existing in the prior art, an embodiment of the present invention provides an ultrasonic detection system, which includes a mixed wave generating circuit, an ultrasonic generating module, an amplifying and filtering circuit module, an associated calculation circuit module, and a CPU processing unit.

[0020] The mixed wave generating circuit is used to mix and superimpose excitation waves of at least two different frequencies and output the mixed wave to the ultrasound generating module. The excitation waves in this embodiment may be in the form of chirp waves, pulse waves, etc.

[0021] The ultrasonic wave generating module is used to generate ultrasonic signals having at least two different detection ranges based on the mixed and superimposed excitation waves. Optionally, the ultrasonic wave generating module in this embodiment may be a microphone, an ultrasonic sensor, or other component.

[0022] the amplification and filtering circuit module is used to perform amplification and filtering processing on the echo signals received by the ultrasound generation module; the associated calculation circuit module includes at least two associated calculation circuits, each of which is used to perform correlation calculation between the echo signal after amplification and filtering and a corresponding reference wave, to obtain correlation calculation results for different detection ranges; The CPU processing unit includes a presence angle determination processing module, an excitation wave generation processing module, a reference wave generation processing module, and a presence angle output module. The presence angle determination processing module is used to determine distance information and presence angle of a measured object based on calculation results of correlations between different detection ranges, the excitation wave generation processing module is used to generate excitation waves of at least two different frequencies, the reference wave generation processing module is used to generate reference waves corresponding to the ultrasonic signals with different detection ranges, and the presence angle output module is used to output the distance and presence angle of the measured object.

[0023] Specifically, the existence angle determination processing module specifically: Identifying the presence angle of the object to be measured based on the correlation calculation result and a pre-established correlation between the correlation value and the object presence angle; The detection time of the object to be measured is obtained based on the correlation peak value, and distance information of the object to be measured is calculated based on the detection time.

[0024] In addition, constructing a relation between the correlation value and the object existence angle is Obtaining correlation values ​​between the ultrasonic echo signals and the reference wave corresponding to different detection angles; and establishing a correlation relationship between the correlation value and the object presence angle based on the detected angle and the corresponding correlation calculation result.

[0025] In this embodiment, since there are multiple detection ranges of the ultrasonic waves, the calculated correlation values ​​corresponding to different detection positions are also different, and by converting the detected position of the object into the existence angle, a relationship between the correlation value and the existence angle can be established. When detecting an object, the existence angle of the measured object can be correspondingly determined based on the calculated different correlation values.

[0026] In an embodiment of the present invention, ultrasonic signals with different detection ranges are generated by transmitting excitation waves of different frequencies to the same ultrasonic generating module, and the pre-established correlation between the correlation value and the object presence angle is used to determine the distance information and presence angle of the measured object based on the correlation value between the ultrasonic echo signal and the corresponding reference signal. If there is no need to use an "ultrasonic detection system" with multiple "microphones" or multiple ultrasonic sensors, the ultrasonic detection system using only one "microphone" or one ultrasonic sensor can simultaneously detect the distance and presence angle of an object, improving the stability of the ultrasonic detection process.

[0027] Next, the above technical solutions will be further explained and illustrated using two examples.

[0028] Example 1 The ultrasonic mixed wave detection system provided in Example 1 of the present invention uses multiple different chirp waves, and Figure 5 shows the ultrasonic directivity generated by this system. Typically, an "ultrasonic microphone" used in an ultrasonic detection device emits ultrasonic waves by attaching a piezoelectric element to a metal case such as aluminum, and generating vibrations when excited by an applied transmission wave. The emitted radiation intensity has a specific radiation intensity depending on the diameter and frequency of the vibration source. The characteristics of the ultrasonic radiation intensity are called directional characteristics. In the present invention, different directional characteristics are generated by using multiple frequencies. Furthermore, since an "ultrasonic microphone" has a resonance point, transmission / reception sensitivity is high near the resonance point, but sensitivity decreases at frequencies away from the resonance point, requiring sensitivity correction.

[0029] In this example, three operating frequencies are used: fm1 = 40 [kHz], fm2 = 60 [kHz], and fm3 = 80 [kHz]. Using the sensitivity of fm1 = 40 [kHz] as the reference, the sensitivity of fm2 = 60 [kHz] is lower by K60-40 [dB] compared to fm1 = 40 [kHz], and the sensitivity of fm3 = 80 [kHz] is lower by K80-40 [dB] compared to fm1 = 40 [kHz]. These values ​​are corrected in the following calculations.

[0030] Figure 6 shows the detection area range of the ultrasonic mixed wave detection system of the present invention. Only K60-40[dB] and K80-40[dB] have been modified, so in the technical solution described below, the detection area ranges will be written as Detection Area_fm1=40[kHz], Detection Area_fm2=60[kHz], and Detection Area_fm3=80[kHz].

[0031] 7 shows the system configuration of the first embodiment of the present invention. The system includes a mixed wave generating circuit, a microphone, an amplifying and filtering circuit module, an associated calculation circuit module, and a CPU processing unit. (1) The mixed wave generation circuit mixes and superimposes the different chirp waves generated by the “chirp wave generation processing” module and outputs them to the microphone. (2) The microphone generates an ultrasonic signal. (3) The amplification and filtering circuit module performs amplification and filtering on the reflected echo received by the microphone. (4) The related calculation circuit module includes multiple related calculation circuits, and each related calculation circuit uses a device capable of high-speed calculation processing, such as a DSP, to perform related calculation processing on the signal after amplification and filtering processing and the “reference wave output” generated from the chirp wave, input the processing result to the existence angle determination module for processing, obtain the existence angle determination result, and output it by the existence angle output processing module, and at the same time, the distance can also be synchronously calculated and output.

[0032] (5) The CPU processing unit includes a plurality of Chirp wave generation processing modules, a reference wave generation processing module corresponding to the Chirp waves, a presence angle determination processing module that processes the related calculation results, and its output processing module. Based on the calculation results output by the "related calculation circuit module," the CPU processing unit determines the "distance" and "presence angle" of the object presence and outputs the detection results.

[0033] FIG. 8 shows the chirp wave mixture of Example 1 of the present invention. The transmission times of the multiple chirp waves are between t0 and t1, and the scan frequencies are Fc1_0-Fc1_1, Fc2_0-Fc2_1, and Fc3_0-Fc3_1, respectively. These frequencies use the above-mentioned frequency bands fm1=40 [kHz], fm2=60 [kHz], and fm3=80 [kHz]. After the chirp mixture wave is transmitted by the "microphone," the "microphone" receives the reflected wave from the object, which then enters the "amplification and filtering circuit" module for processing. Here, the time when the reflected wave from the object is received is designated as t2.

[0034] 9 to 11 are schematic diagrams showing correlation value calculations in the first embodiment of the present invention. Fig. 9 shows the correlation calculation results for object position 1, Fig. 10 shows the correlation calculation results for object position 2, and Fig. 11 shows the correlation calculation results for object position 3.

[0035] In Figure 9, the related calculations between "Reference Wave.1" and the "Amplification Filtering Circuit Output", the related calculations between "Reference Wave.2" and the "Amplification Filtering Circuit Output", and the related calculations between "Reference Wave.3" and the "Amplification Filtering Circuit Output" are processed in parallel. The related calculations were explained in Figure 3 above. Object Position.1 is when there is an object in the front direction, and the objects are all within the ranges of Detection Area_fm1 = 40 [kHz], Detection Area_fm2 = 60 [kHz], and Detection Area_fm3 = 80 [kHz]. Comparing the three "correlation value calculation results" at reception time t2, "Correlation Value.1 Calculation Result: Vout.1" ≒ "Correlation Value.2 Calculation Result: Vout.2" ≒ "Correlation Value.3 Calculation Result: Vout.3".

[0036] In Figure 10, when an object is located slightly off the midline, the object is within Detection Area_fm1 = 40 [kHz] and Detection Area_fm2 = 60 [kHz], but not within Detection Area_fm3 = 80 [kHz]. Comparing the three "calculation results of correlation values" at reception time t2, the order is "calculation result of correlation value 1: Vout.1" > "calculation result of correlation value 2: Vout.2" > "calculation result of correlation value 3: Vout.3".

[0037] In Figure 11, when an object is located outside the vehicle, object position 3 is within Detection Area_fm1 = 40 [kHz], but is not within Detection Area_fm2 = 60 [kHz] or Detection Area_fm3 = 80 [kHz]. Comparing the three "correlation value calculation results" at reception time t2, the order is "correlation value 1 calculation result: Vout.1" > "correlation value 2 calculation result: Vout.2" > "correlation value 3 calculation result: Vout.3".

[0038] FIG. 12 shows a method for determining an angle of presence according to a first embodiment of the present invention. FIG. 12(1) shows the relationship between the correlation value calculation result Vout and the object position. The correlation value calculation result Vout changes depending on the position of the object, and FIG. 12(2) shows the relationship between the correlation value calculation result Vout and the object angle. When the object position in FIG. 12(1) is converted to the angle at which the object is present, the result is shown in FIG. 12(2). That is, as the angle at which the object is present increases, the result of Vout.2 - Vout.1 or Vout.3 - Vout.1 forms a curve that increases with increasing angle. By comparing the calculated "correlation value 1 calculation result Vout.1," "correlation value 2 calculation result Vout.2," and "correlation value 3 calculation result Vout.3" with the curve, the angle and distance at which the object is present can be determined.

[0039] FIG. 13 shows two application examples of determining the existence angle in the first embodiment of the present invention. In the detection of horizontal angles in Figure 13(1), we show that an ultrasonic detection system can be realized that can simultaneously detect the "distance" and "existence angle" of an object in the horizontal direction using only one "ultrasonic microphone."

[0040] In the vertical angle detection of Figure 13(2), the "distance" and "existence angle" of an object can be detected simultaneously in the vertical direction, so it is possible to determine whether the object is an "opposing object" located in the front direction or a "road surface object" located on the road surface.

[0041] Example 2 The system according to the second embodiment of the present invention uses a plurality of pulse waves.

[0042] 14 shows the system configuration of the second embodiment of the present invention. The system includes a mixed wave generating circuit, a microphone, an amplifying and filtering circuit module, an associated calculation circuit module and a CPU processing unit. (1) The mixed wave generation circuit mixes and superimposes the different pulse waves generated by the “pulse wave generation processing” module and outputs them to the microphone. (2) The microphone generates an ultrasonic signal. (3) The amplification and filtering circuit module performs amplification and filtering on the reflected echo received by the microphone. (4) The related calculation circuit module includes multiple related calculation circuits, and each related calculation circuit uses a device capable of high-speed calculation processing such as a DSP, performs related calculation processing on the signal after amplification and filtering processing and the ``reference wave output'' generated from the pulse wave, inputs the processing result to the existence angle determination module for processing, obtains the existence angle determination result and outputs it by the existence angle output processing module, and at the same time, the distance can also be synchronously calculated and output. (5) The CPU processing unit includes a generation processing module for multiple pulse waves, a reference wave generation processing module corresponding to the pulse waves, a presence angle determination processing module that processes the related calculation results, and an output processing module. Based on the calculation results output by the "related calculation circuit module," the CPU processing unit determines the "distance" and "presence angle" at which an object exists and outputs the detection results.

[0043] 15 shows a mixing of pulse waves in Example 2 of the present invention. The transmission times of the multiple pulse waves are between t0 and t1, and the frequencies are the single frequencies Fc1, Fc2, and Fc3, respectively. These frequencies use the frequency bands fm1=40[kHz], fm2=60[kHz], and fm3=80[kHz].

[0044] 16 to 18 show correlation value calculations in Example 2 of the present invention. Fig. 16 shows the calculation results for object position 1, Fig. 17 shows the calculation results for object position 2, and Fig. 18 shows the calculation results for object position 3. The related calculation method has already been shown in Fig. 3, and although the waveforms of the correlation value calculation results for pulse waves are different, the calculation method is the same.

[0045] In Figure 16, when an object is located in the front direction, the object is located within the ranges of Detection Area_fm1 = 40 [kHz], Detection Area_fm2 = 60 [kHz], and Detection Area_fm3 = 80 [kHz], and when the three "calculation results of correlation values" at reception time t2 are compared, "calculation result of correlation value 1: Vout.1" ≒ "calculation result of correlation value 2: Vout.2" ≒ "calculation result of correlation value 3: Vout.3".

[0046] In Figure 17, when an object is located slightly off the midline, the object is within Detection Area_fm1 = 40 [kHz] and Detection Area_fm2 = 60 [kHz], but not within Detection Area_fm3 = 80 [kHz]. Comparing the three "correlation value calculation results" at reception time t2, the order is "correlation value 1 calculation result: Vout.1" > "correlation value 2 calculation result: Vout.2" > "correlation value 3 calculation result: Vout.3".

[0047] In Figure 18, when an object is located outside the vehicle, the object is within Detection Area_fm1 = 40 [kHz], but is not within Detection Area_fm2 = 60 [kHz] or Detection Area_fm3 = 80 [kHz]. Comparing the three "correlation value calculation results" at reception time t2, the order is "correlation value 1 calculation result: Vout.1" > "correlation value 2 calculation result: Vout.2" > "correlation value 3 calculation result: Vout.3".

[0048] By comparing the "calculation result of correlation value 1," "calculation result of correlation value 2," and "calculation result of correlation value 3," it is possible to simultaneously detect the "distance" and "existence angle" of an object.

[0049] It should be noted that the above are relatively preferred embodiments and operating technical principles of the present invention. Those skilled in the art will understand that the present invention is not limited to the specific embodiments described herein, and that those skilled in the art can make various obvious changes, adjustments, and substitutions without departing from the scope of protection of the present invention. Therefore, although the present invention has been described in detail through the above embodiments, the present invention is not limited to the above embodiments, and can include many other equivalent embodiments without departing from the concept of the present invention, and the scope of the present invention is determined by the scope of the appended claims.

Claims

1. 1. An ultrasound detection system comprising: The device includes a mixed wave generating circuit, an ultrasonic wave generating module, an amplifying and filtering circuit module, an associated calculation circuit module, and a CPU processing unit; The mixed wave generating circuit is used to mix and superimpose excitation waves of at least two different frequencies and output the mixed waves to the ultrasonic wave generating module; The ultrasonic wave generating module is used to generate ultrasonic signals having at least two different detection ranges according to the mixed and superimposed excitation waves; the amplification and filtering circuit module is used to perform amplification and filtering processing on the echo signals received by the ultrasound generation module; the associated calculation circuit module includes at least two associated calculation circuits, each of which is used to perform correlation calculation between the amplified and filtered echo signal and a corresponding reference wave to obtain correlation calculation results for different detection ranges; the CPU processing unit includes a presence angle determination processing module, and the presence angle determination processing module is used to determine distance information and a presence angle of the measured object based on a calculation result of the correlation degree of different detection ranges; Specifically, the existence angle determination processing module: Identifying the presence angle of the object to be measured based on the correlation calculation result and a pre-established correlation between the correlation value and the object presence angle; obtaining a detection time of the measured object based on the correlation peak value; and calculating distance information of the measured object based on the detection time; Establishing a relation between the correlation degree value and the object existence angle includes: Obtaining correlation degree values ​​between the ultrasonic echo signals and the reference wave corresponding to different detection angles; and establishing a correlation relationship between the correlation value and the object presence angle based on the detected angle and the corresponding correlation calculation result.

2. 10. The system of claim 1, wherein the CPU further includes an excitation wave generation processing module, the excitation wave generation processing module being used to generate excitation waves of at least two different frequencies.

3. The system of claim 1, wherein the CPU further includes a reference wave generation processing module, and the reference wave generation processing module is used to generate reference waves corresponding to the at least two ultrasonic signals having different detection ranges.

4. The system according to claim 1 , wherein the CPU further includes an existence angle output module, the existence angle output module being used to output the distance and existence angle of the measured object.

5. An ultrasonic detection method based on the ultrasonic detection system according to any one of claims 1 to 4, Simultaneously transmitting mixed excitation waves of at least two different frequencies to a single ultrasonic wave generating module, so that the ultrasonic wave generating module correspondingly generates ultrasonic signals with at least two different detection ranges; receiving echo signals of an ultrasonic signal and calculating a correlation between each of the echo signals and a corresponding reference wave; determining the angle of presence and distance information of the object to be measured based on the correlation degree calculation result; Identifying the presence angle and distance information of the object to be measured based on the correlation degree calculation result, Identifying the presence angle of the object to be measured based on the correlation calculation result and a pre-established correlation between the correlation value and the object presence angle; obtaining a detection time of the object to be measured based on the correlation peak value; and calculating distance information of the object to be measured based on the detection time; Establishing a relation between the correlation degree value and the object existence angle includes: Obtaining correlation degree values ​​between the ultrasonic echo signals and the reference wave corresponding to different detection angles; and establishing a correlation relationship between the correlation value and the object presence angle based on the detected angle and the corresponding correlation calculation result.

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