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 DISCLOSURE 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 the reflected wave from an object using the wave emitted by the "ultrasonic microphone," the distance to the obstacle can be known, but it is not possible to determine from which position on the concentric circle centered on the "ultrasonic microphone" the distance is reflected, or to specify the area and angle of the object's existence, and when angle detection in the vertical direction is required in particular, for example, when trying to distinguish whether the obstacle is an "opposing object" present in front or a "road object" present on the road surface, the error rate becomes significantly high. Many ultrasonic detection system products currently on the market are unable to accurately determine the "existence angle" 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 presence angle of an object with an ultrasonic detection system 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: Including a mixed wave generating circuit, an ultrasonic 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 waves to the ultrasonic generating module, The ultrasonic 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 signal 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 of different detection ranges; The CPU processing unit includes a presence angle determination processing module, which is used for determining the distance information and the 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, the excitation wave generation processing module being used to generate excitation waves of at least two different frequencies.

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

[0007] Optionally, the existence angle determination processing module specifically includes: Identifying a presence angle of a measured object based on the correlation degree calculation result and a previously established association relationship between the correlation degree value and the object presence angle; The correlation peak value is used to obtain a detection time of the measured object based on the correlation peak value, and calculate distance information of the measured object based on the detection time.

[0008] Optionally, establishing an association relationship between the correlation degree value and the object presence angle includes: Obtaining correlation degree values ​​between the ultrasonic echo signals corresponding to different detection angles and the reference wave; 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 an 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 same 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 the echo signals and corresponding reference waves; and determining the presence angle and distance information of the object to be measured based on the result of the correlation degree calculation.

[0010] Selectively determining the presence angle and distance information of the measured object based on the correlation degree calculation result includes: Identifying a presence angle of a measured object based on the correlation degree calculation result and a previously established association relationship between the correlation degree value and the object presence angle; The method includes 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.

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

[0012] The embodiment of the present invention generates ultrasonic signals with different detection ranges by transmitting excitation waves of different frequencies to the same ultrasonic generating module, and identifies the distance information and the presence angle of the measured object based on the correlation value between the ultrasonic echo signal and the corresponding reference signal according to the pre-established correlation relationship between the correlation value and the object presence angle. In the case of an "ultrasonic detection system" that does not need to use multiple "microphones" or multiple 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 description of the drawings]

[0013] [Figure 1] FIG. 1 shows a configuration diagram of a conventional system. [Diagram 2] 1 shows a schematic diagram of a conventional chirp wave. [Diagram 3] 1 shows a schematic diagram of a conventional correlation value calculation method. [Figure 4(1)] 1 shows a schematic diagram of 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 ultrasonic transmission and reception sensitivity in Example 1 of the present invention. [Figure 6(1)] 4 is a schematic diagram of a detection area range (after K correction) of a horizontal angle in the first embodiment of the present invention. FIG. [Figure 6 (2)] 4 is a schematic diagram of a detection area range (after K correction) of a vertical angle in the first embodiment of the present invention. FIG. [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 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_object position 3 according to the first embodiment of the present invention. [Figure 12(1)] 13 is a schematic diagram showing the relationship between the correlation value calculation result Vout and the object position. [Figure 12 (2)] 13 is a schematic diagram showing the relationship between the correlation value calculation result Vout and the object angle. [Figure 13(1)] 1 is a schematic diagram showing an application of determining a horizontal direction existence angle according to the first embodiment of the present invention; [Figure 13(2)] 1 is a schematic diagram showing an application of determining a vertical direction existence angle according to a first embodiment of the present invention; [Figure 14] FIG. 13 shows a system configuration diagram of a second embodiment of the present invention. [Figure 15] FIG. 13 is a schematic diagram of pulse wave mixing according to a second embodiment of the present invention. [Figure 16] 1 shows a schematic diagram of a correlation value calculation method_object position 1 according to a second embodiment of the present invention. [Figure 17] 13 is a schematic diagram of a correlation value calculation method_object position 2 according to the second embodiment of the present invention. [Figure 18] 13 is a schematic diagram of a correlation value calculation method_object position 3 according to the second embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[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 embodiments 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 related to the present invention, and not the entire structure. In order to better understand the technical solutions of the embodiments of the present invention, the ultrasonic detection method commonly used in the prior art will be introduced first. The system configuration diagram of the ultrasonic detection system in the prior art is shown in Figure 1, which includes a chirp wave generating circuit, an ultrasonic 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 generating module to transmit ultrasonic waves. (2) The ultrasonic generating module transmits chirp-type ultrasonic waves. (3) The amplification and filtering circuit amplifies the reflected received wave from the object to obtain an amplification and filtering circuit output signal. (4) The associated calculation circuit uses a device capable of high-speed calculation processing, such as a DSP, to perform associated 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, judges the distance of the object, and outputs the detection result.

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

[0016] FIG. 3 shows a correlation value calculation method in the prior art. First, the correlation value at time t0 is calculated by the following method: multiplying "reference wave_0000" and "amplification filtering circuit output", adding the multiplication results, and storing the obtained sum as the correlation value at time t0 in "calculation result of correlation value". Next, "reference wave_0001" is obtained by delaying one period, and "reference wave_0001" and "amplification filtering circuit output" are multiplied, and the multiplication results are added, and the obtained sum is stored as the correlation value at time t1. This process is repeated in order. That is, the correlation value calculation corresponds to calculating the correlation between the two. In the vicinity of t2 where the reflected wave from the object exists, the correlation value between the "reference wave" and the "amplification filtering circuit output" becomes large, so the value of the "calculation result of correlation value" also becomes large.

[0017] After calculating the correlation values ​​at all times, when the correlation value calculation result is judged based on the threshold, if the correlation value calculation result is greater than the correlation degree threshold, it is considered that the presence of an obstacle has been detected, and the time t2 at which the peak value of the correlation value appears is searched for. In this way, if the reception time is converted into the distance to the object, the detection distance to the object can be calculated. In the conventional example, the distance to the object can be output, but as shown in the detection of the horizontal angle in FIG. 4(1), it is not possible to specify from which position on the concentric circle centered on the "ultrasonic microphone" this distance is reflected, and it is also not possible to specify the presence area and presence angle of the object. In response to this problem, the technical solution normally adopted in many ultrasonic inspection system products currently on the market combines multiple ultrasonic sensors and judges in which area the object is located from the results of each, that is, multiple ultrasonic sensors are required to judge the area. However, many ultrasonic detection system products currently on the market cannot accurately judge the presence angle of the object.

[0018] As shown in the vertical angle detection in FIG. 4(2), in the vertical direction, the conventional system cannot distinguish whether a detected object is an "opposing object" present in the front direction or a "road object" present on the road surface. In the case of a road object, for example, it should be possible to effectively detect and distinguish the direction of a large road object such as a road edge (stone curve), 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" 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 existence angle.

[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 computing 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 ultrasonic generating module. The excitation wave in this embodiment may be in the form of a chirp wave, a pulse wave, or the like.

[0021] The ultrasonic generating module is used to generate ultrasonic signals having at least two different detection ranges according to the excitation waves after mixing and superimposition. Optionally, the ultrasonic generating module in this embodiment may be a microphone, an ultrasonic sensor, or other components.

[0022] The amplification and filtering circuit module is used to perform amplification and filtering processing on the echo signal 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 of 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 the distance information and the presence angle of the measured object based on the calculation result of the correlation degree of 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 of the at least two detection ranges respectively, and the presence angle output module is used to output the distance and the presence angle of the measured object.

[0023] Specifically, the existence angle determination processing module specifically includes: Identifying a presence angle of a measured object based on the correlation degree calculation result and a previously established association relationship between the correlation degree value and the object presence angle; The correlation peak value is used to obtain a detection time of the measured object based on the correlation peak value, and calculate distance information of the measured object based on the detection time.

[0024] In addition, constructing a relation between the correlation degree value and the object existence angle is Obtaining correlation degree values ​​between the ultrasonic echo signals corresponding to different detection angles and the reference wave; 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 wave, the correlation calculation value corresponding to different detection positions is also different, and the detection position of the object is converted into the existence angle, so that 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 different correlation values ​​obtained by calculation.

[0026] In the embodiment of the present invention, ultrasonic signals with different detection ranges are generated by transmitting excitation waves with different frequencies to the same ultrasonic generating module, and the correlation between the correlation value and the object presence angle is established in advance to identify the distance information and the presence angle of the measured object based on the correlation value between the ultrasonic echo signal and the corresponding reference signal. When 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 detect the distance and presence angle of simultaneous objects, improving the stability of the ultrasonic detection process.

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

[0028] Example 1 The ultrasonic mixed wave detection system provided by the first embodiment of the present invention uses multiple different Chirp waves, and FIG. 5 shows the ultrasonic directivity generation of the system. Usually, 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 by excitation with an applied transmission wave. The emitted radiation intensity has a specific radiation intensity depending on the diameter and frequency of the vibration source. The characteristic of the radiation intensity of ultrasonic waves is called the directional characteristic. In the present invention, different directional characteristics are generated by using multiple frequencies. Also, since the "ultrasonic microphone" has a resonance point, the transmission / reception sensitivity is high near the resonance point, but the sensitivity decreases for frequencies away from the resonance point, so the sensitivity needs to be corrected.

[0029] In this embodiment, three frequencies are used: fm1=40[kHz], fm2=60[kHz], and fm3=80[kHz]. The sensitivity of fm1=40[kHz] is used as a reference, and fm2=60[kHz] is lower than fm1=40[kHz] by K60-40[dB], and fm3=80[kHz] is lower than fm1=40[kHz] by K80-40[dB], so these are corrected in the following calculations.

[0030] 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] are modified, so in the technical proposal described below, the detection area range is written as Detection Area_fm1=40[kHz], Detection Area_fm2=60[kHz], Detection Area_fm3=80[kHz].

[0031] FIG. 7 shows a 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 processing on the reflected echo received by the microphone. (4) The associated calculation circuit module includes a plurality of associated calculation circuits, and each associated calculation circuit uses a device capable of performing high-speed calculation processing, such as a DSP, to perform associated calculation processing on the signal after the amplification and filtering processing and the "reference wave output" generated from the Chirp wave, inputting the processing result to the existence angle determination module for processing, obtaining the existence angle determination result and outputting it by the existence angle output processing module, and at the same time, synchronously calculating and outputting the distance.

[0032] (5) The CPU processing unit includes a generation processing module for multiple Chirp waves, a reference wave generation processing module corresponding to the above-mentioned Chirp waves, a presence angle determination processing module which processes the related calculation results, and an output processing module. Based on the calculation results output by the "related calculation circuit module", it determines the "distance" and "presence angle" of the object presence and outputs the detection results.

[0033] FIG. 8 shows the mixing of chirp waves in the first embodiment of the present invention. The transmission times of the multiple chirp waves are between t0 and t1, and the scanning frequencies are Fc1_0-Fc1_1, Fc2_0-Fc2_1, and Fc3_0-Fc3_1, respectively. These frequencies use the above-mentioned frequency bands of fm1=40[kHz], fm2=60[kHz], and fm3=80[kHz]. After the chirp mixed wave is transmitted by the "microphone", the "microphone" receives the reflected wave from the object, and enters the "amplification filtering circuit" module for processing. Here, the time when the reflected wave from the object is received is set to 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 FIG. 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 FIG. 3 above. Object position.1 is the case where there is an object in the front direction, and the object is all within the ranges of Detection Area_fm1=40[kHz], Detection Area_fm2=60[kHz], and Detection Area_fm3=80[kHz], and when comparing the three "calculation results of correlation values" 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 object position 2 in Figure 10, if an object is located slightly off-center from 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".

[0037] In object position 3 in Figure 11, when an object is present outside the vehicle, the object is within the range of Detection Area_fm1 = 40 [kHz], but is not within the ranges of 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 of the present invention in the first embodiment. 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 object's position, 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 exists, it becomes FIG. 12(2). That is, when the object's angle of presence increases, the result of Vout.2-Vout.1 or Vout.3-Vout.1 is a curve that increases with the increase in the angle. By comparing the "correlation value.1 calculation result Vout.1", "correlation value.2 calculation result Vout.2", and "correlation value.3 calculation result Vout.3" after calculation with the curve, the angle and distance at which the object exists can be determined.

[0039] FIG. 13 shows two application examples of the determination of 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 in Figure 13 (2), it is possible to simultaneously detect the “distance” and “existence angle” of an object 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 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] FIG. 14 shows a 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 processing on the reflected echo received by the microphone. (4) The associated calculation circuit module includes a plurality of associated calculation circuits, and each associated calculation circuit uses a device capable of performing high-speed calculation processing such as a DSP, performs associated calculation processing on the signal after the amplified 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 above-mentioned pulse waves, a presence angle determination processing module that processes related calculation results, and an output processing module. Based on the calculation results output by the "related calculation circuit module", it determines the "distance" and "presence angle" at which an object exists and outputs the detection result.

[0043] 15 shows a mixing of pulse waves according to the second embodiment 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] Fig. 16 to Fig. 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 the pulse wave 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 range of Detection Area_fm1 = 40 [kHz], Detection Area_fm2 = 60 [kHz], and Detection Area_fm3 = 80 [kHz], and when the three "correlation value calculation results" at reception time t2 are compared, "correlation value.1 calculation result: Vout.1" ≒ "correlation value.2 calculation result: Vout.2" ≒ "correlation value.3 calculation result: Vout.3".

[0046] In object position 2 in Figure 17, if an object is located slightly off the midline, the object is within the ranges of Detection Area_fm1 = 40 [kHz] and Detection Area_fm2 = 60 [kHz], but not within the range of 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 object position 3 in Figure 18, when an object is present outside the vehicle, the object is within the range of Detection Area_fm1 = 40 [kHz], but is not within the ranges of 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" at which an object is present.

[0049] It should be noted that the above are the relatively preferred embodiments and the operating technical principles of the present invention. Those skilled in the art can understand that the present invention is not limited to the specific embodiments described herein, and 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: Including a mixed wave generating circuit, an ultrasonic generating module, an amplifying and filtering circuit module, an associated computing circuit module, and a CPU processing unit; The mixed wave generating circuit is used for mixing and superimposing excitation waves of at least two different frequencies and outputting the mixed waves to an ultrasonic generating module; The ultrasonic 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 signal 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 of different detection ranges; an ultrasonic detection system, characterized in that 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 a measured object based on a calculation result of a correlation degree of different detection ranges.

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

3. The system described in claim 1, characterized in that the CPU further includes a reference wave generation processing module, the reference wave generation processing module being 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 for outputting a distance and an existence angle of a measured object.

5. Specifically, the existence angle determination processing module includes: Identifying a presence angle of a measured object based on the correlation degree calculation result and a previously established association relationship between the correlation degree value and the object presence angle; The system according to claim 1, characterized in that it is used to obtain a detection time of the measured object based on the correlation peak value, and calculate distance information of the measured object based on the detection time.

6. Establishing a relation between the correlation degree value and the object existence angle includes: Obtaining correlation degree values ​​between the ultrasonic echo signals corresponding to different detection angles and the reference wave; 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.

7. An ultrasonic detection method based on the ultrasonic detection system according to any one of claims 1 to 6, Simultaneously transmitting at least two mixed excitation waves of different frequencies to a same 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 the echo signals and corresponding reference waves; and determining an angle of presence and distance information of the measured object based on the correlation degree calculation result.

8. Identifying the presence angle and distance information of the measured object based on the correlation degree calculation result, Identifying a presence angle of a measured object based on the correlation degree calculation result and a previously established association relationship between the correlation degree value and the object presence angle; 8. The method according to claim 7, further comprising: 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.

9. Establishing a relation between the correlation degree value and the object existence angle includes: Obtaining correlation values ​​between the ultrasonic echo signals corresponding to different detection angles and the reference wave; 9. The method of claim 8, further comprising: establishing a correlation relationship between the correlation value and the object presence angle based on the detected angle and the corresponding correlation calculation result.

Images