CN111443254B - Ultrasonic reflection performance detection system and method - Google Patents
Ultrasonic reflection performance detection system and method Download PDFInfo
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- CN111443254B CN111443254B CN202010313710.5A CN202010313710A CN111443254B CN 111443254 B CN111443254 B CN 111443254B CN 202010313710 A CN202010313710 A CN 202010313710A CN 111443254 B CN111443254 B CN 111443254B
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R31/00—Arrangements for testing electric properties; Arrangements for locating electric faults; Arrangements for electrical testing characterised by what is being tested not provided for elsewhere
- G01R31/001—Measuring interference from external sources to, or emission from, the device under test, e.g. EMC, EMI, EMP or ESD testing
- G01R31/002—Measuring interference from external sources to, or emission from, the device under test, e.g. EMC, EMI, EMP or ESD testing where the device under test is an electronic circuit
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- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N29/00—Investigating or analysing materials by the use of ultrasonic, sonic or infrasonic waves; Visualisation of the interior of objects by transmitting ultrasonic or sonic waves through the object
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Abstract
The application discloses ultrasonic reflection performance detecting system and method for testing ultrasonic performance of electronic equipment, the ultrasonic reflection performance detecting system includes: sealing the box body; the motion guide rail is arranged in the closed box body; the reflecting component is connected with the motion guide rail in a sliding way; the electronic equipment and the reflecting component are respectively positioned at two ends of the motion guide rail, and in the process that the electronic equipment and the reflecting component are close to each other, ultrasonic signals emitted by the electronic equipment are reflected by the reflecting component and received by the electronic equipment. The detection system provided by the application can improve the ultrasonic detection precision.
Description
Technical Field
The present application relates to the field of ultrasound technologies, and in particular, to a system and a method for detecting an ultrasound reflection performance.
Background
With the development of communication technology, ultrasound technology has been widely applied to electronic devices. Ultrasound applications on electronic devices include: ultrasonic ranging, ultrasonic proximity sensing, gesture recognition, and the like. Before the electronic equipment leaves a factory, ultrasonic reflection performance detection is required, and only the electronic equipment which passes the ultrasonic reflection performance detection is allowed to enter the market.
The ultrasonic reflection performance detection method in the prior art comprises the following steps: the receiver of the electronic equipment sends an ultrasonic signal, the ultrasonic signal is reflected by the reflecting component and then received by the microphone of the electronic equipment, and the ultrasonic reflection performance of the electronic equipment is determined according to the energy amplitude of the received ultrasonic signal.
Content of application
The application provides an ultrasonic reflection performance detection system and method, which can improve the detection precision of ultrasonic reflection performance.
In order to solve the technical problem, the present application is implemented as follows:
in a first aspect, the present application provides an ultrasonic reflection performance testing system for testing ultrasonic performance of an electronic device, the ultrasonic reflection performance testing system comprising:
sealing the box body;
the motion guide rail is arranged in the closed box body;
the reflecting component is connected with the motion guide rail in a sliding way;
the electronic equipment and the reflecting component are respectively positioned at two ends of the moving guide rail, and in the process that the electronic equipment and the reflecting component are close to each other, ultrasonic signals emitted by the electronic equipment are reflected by the reflecting component and received by the electronic equipment.
In a second aspect, the present application provides an ultrasonic reflection performance detection method, which is applied to the ultrasonic reflection performance detection system, and the ultrasonic reflection performance detection method includes:
When the reflecting component is located at a preset distance relative to the electronic equipment, the electronic equipment receives a first ultrasonic detection signal;
the electronic equipment receives a second ultrasonic detection signal in the process that the reflecting component approaches from the preset distance relative to the electronic equipment;
the electronic equipment determines the ultrasonic reflection performance of the electronic equipment according to the first ultrasonic detection signal and the second ultrasonic detection signal.
By adopting the ultrasonic reflection performance detection system, when the ultrasonic performance of the electronic equipment is detected, the electronic equipment and the reflection part can be respectively positioned at two ends of the motion guide rail, and the electronic equipment and the reflection part are close to each other.
Drawings
FIG. 1 shows a model schematic when an electronic device receives an ultrasound signal;
FIG. 2 illustrates a schematic structural diagram of an ultrasonic reflective performance detection system provided according to an embodiment of the present application;
FIG. 3 is a schematic diagram illustrating an ultrasonic reflective performance detection system according to another embodiment of the present application;
FIG. 4 is a schematic flow chart diagram illustrating a method for detecting ultrasonic reflection performance according to an embodiment of the present application;
figure 5 illustrates an ultrasound signal profile provided in accordance with one embodiment of the present application.
Detailed Description
The technical solutions in the present application will be described clearly and completely with reference to the accompanying drawings in the present application, and it is obvious that the described embodiments are some, not all embodiments of the present application. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present application.
Fig. 1 shows a model diagram of an electronic device receiving an ultrasonic signal when an obstacle is in front. As shown in fig. 1, an ultrasonic signal received by a microphone of an electronic device is actually a superposition of ultrasonic signals of three paths, where path 1 is a direct ultrasonic signal, and represents a signal component in which an ultrasonic signal sent by a receiver of the electronic device directly passes through air and enters the microphone without passing through an obstacle; the path 2 is an internal leakage ultrasonic signal and represents a signal component of an ultrasonic signal sent by a receiver which directly passes through an internal structure without passing through an obstacle and is transmitted into a microphone; the path 3 is a reflected ultrasonic signal, which represents a signal component of an ultrasonic signal transmitted by the receiver and transmitted into the microphone after being reflected by an external obstacle.
Because the ultrasonic reflection performance of the electronic equipment is only related to the reflected ultrasonic signal, when the ultrasonic reflection performance of the electronic equipment is represented by using the energy amplitude of the ultrasonic signal (i.e. the superimposed signal) received by the microphone, the detection result of the ultrasonic reflection performance is interfered by the direct ultrasonic signal and the internally leaked ultrasonic signal, so that the detection precision is low.
Fig. 2 shows a schematic structural diagram of an ultrasonic reflection performance detection system provided in an embodiment of the present application, which is used for testing the ultrasonic performance of an electronic device. As shown in fig. 2, the ultrasonic reflection performance detecting system includes: a closed box 201, a motion guide rail 202 and a reflecting component 203.
The closed sound insulation box 201 is used for isolating the interference of external environment noise to ultrasonic signals, and meanwhile, the inner wall of the closed sound insulation box is coated with ultrasonic absorption materials, so that the interference of reflected signals in the box to a detection process can be avoided.
The moving guide 202 is provided inside the sealed sound-insulating case 201, and the reflecting member 203 is slidably connected to the moving guide 202 and can reciprocate in the longitudinal direction of the moving guide 202. The reflecting member 203 may be a baffle for reflecting the ultrasonic signal emitted from the electronic device 204.
Fig. 3 shows a schematic structural diagram of an ultrasonic reflection performance detection system according to another embodiment of the present application. Fig. 3 is different from fig. 2 in that the movement guide 202 in fig. 3 is disposed perpendicular to the horizontal direction, and the reflecting member 203 and the electronic device 204 are disposed parallel to the horizontal direction. The skilled person can select the appropriate guide rail arrangement according to the production line requirements.
As shown in fig. 2 and 3, when detecting the ultrasonic performance of the electronic device 204, the electronic device 204 and the reflecting component 203 may be respectively located at two ends of the moving guide 202, and in a process that the electronic device 204 and the reflecting component 203 approach each other, an ultrasonic signal emitted by the electronic device 204 is reflected by the reflecting component 203 and received by the electronic device 204.
Adopt the supersound reflection performance detecting system of this application, when carrying out the supersound performance detection to electronic equipment, can make electronic equipment and reflection part be located the both ends of motion guide rail respectively, and make electronic equipment and reflection part be close to each other, along with electronic equipment and reflection part be close to each other, the reflection ultrasonic signal that comes from reflection part that electronic equipment received can change thereupon, can follow the supersound detection signal with reflecting ultrasonic signal and isolate according to this change to the supersound reflection performance of accurate reflection electronic equipment.
Next, in the process that the electronic device and the reflection component approach each other, the ultrasonic detection signal received by the electronic device is analyzed to separate the reflected ultrasonic signal from the ultrasonic detection signal.
When the reflection component moves relative to the electronic device, the time domain form of the ultrasonic detection signal received by the electronic device is as follows:
Wherein A (N) represents the intensity of the reflected ultrasonic signal received by the electronic equipment, A (N) τ sin (wt) represents the static signal component received by the electronic equipment when the reflecting component moves relative to the electronic equipment(including the direct ultrasound signal and the internal leakage ultrasound signal), the initial phase of the static signal component is 0,
represents dynamic signal components (including reflected ultrasonic signals), z represents the linear distance of the reflecting component from the electronic device, f (z) represents the intensity of the sound field as a function of distance,
showing the variation of sound field phase with linear distance, and tau is showing static energy coefficient.
According to equation (1), the amplitude of the ultrasound energy for the sampling period t can be expressed as:
by subtracting the square of the ultrasonic energy of two adjacent sampling periods t1 and t2, we can obtain:
comparing the formula (2) and the formula (3), it is found that by making a difference between the squares of the ultrasonic energies of two adjacent sampling periods t1 and t2, the time-dependent variable wt is eliminated, and as wt is eliminated, the phase interference of the static signal component to the reflected ultrasonic signal is also eliminated, so that the reflected ultrasonic signal intensity a (n) becomes a single-term product factor, providing a condition for separating the reflected ultrasonic signal from the ultrasonic detection signal.
Assuming that the relative motion speed is slow (i.e. the interval between z1 and z2 corresponding to two adjacent sampling periods t1 and t2 is very close), f (z2) ≈ f (z1), equation (3) can be simplified as follows:
summing the squared differences of the ultrasonic energy over each two adjacent sampling periods during the movement of the reflecting element relative to the electronic device can obtain:
according to the formula (5), T can be understood as a differential value of the ultrasonic detection signal received by the electronic device during the movement of the reflection component relative to the electronic device, i.e. T represents the energy of the dynamic signal.
By using
By performing a simplification process on equation (5), we can obtain:
wherein, the first and the second end of the pipe are connected with each other,
representing the mean of the reflected ultrasonic energy throughout the relative motion,
representing the mean value of the ultrasonic energy throughout the relative movement, i.e.
It is the static signal energy that is represented,
representing a constant associated with an auxiliary moving device (such as a moving rail) in an ultrasonic reflective performance detection system.
Thus, the reflected ultrasound signal intensity a (n) can be expressed as:
as can be seen from equation (7), the value of A (N) is summed with T
Correlation according to T and
the ratio of (a) to (n) can result in the relative size of a (n), and thus the ultrasonic reflective performance of the electronic device.
Based on the above analysis, the present application provides an ultrasonic reflection performance detection method, which is applied to the ultrasonic reflection performance detection system described above, and as shown in fig. 4, the ultrasonic reflection performance detection method includes:
And step 403, determining the ultrasonic reflection performance of the electronic equipment according to the first ultrasonic detection signal and the second ultrasonic detection signal.
Since the reflecting component does not move relative to the electronic device during the acquisition of the first ultrasonic detection signal, the first ultrasonic detection signal can be used to represent the energy of the static signal
In the acquisition process of the second ultrasonic detection signal, the reflecting component is close to the electronic equipment from the preset distance, so that the second ultrasonic detection signal can be used for representing the dynamic signal energy T, and the ultrasonic reflection performance of the electronic equipment can be represented by the sum of the energy T and the energy T
The ultrasonic reflection performance of the electronic device can thus be determined from the first ultrasonic detection signal and the second ultrasonic detection signal.
In particular, the static signal energy may be calculated from the first ultrasonic detection signal for a consecutive plurality of first sampling periods
And calculating dynamic signal energy T according to the second ultrasonic detection signal of continuous multiple second sampling periods, and then calculating the dynamic signal energy T according to the dynamic signal energy T and the static signal energy 
Determining the ultrasonic reflection performance of the electronic equipment.
Wherein the static signal energy
May be a product of an energy average value of the first ultrasonic detection signal corresponding to the plurality of first sampling periods and a preset coefficient. Because the energy amplitude of each first sampling period in the first ultrasonic detection signal is stable and is not easily influenced by the duration of the first sampling period, the energy of the static signal can be accurately represented by adopting the first ultrasonic detection signal
The dynamic signal energy T may be a difference value of an energy square of the second ultrasonic detection signal corresponding to the plurality of second sampling periods, that is, a cumulative sum of differences of ultrasonic energy squares between every two adjacent second sampling periods in the second ultrasonic detection signals corresponding to the plurality of periods.
The ultrasonic reflection performance detection method in the present application is exemplarily described below with reference to fig. 2 and 3:
s1, stopping the reflection member at a remote position from the electronic apparatus, causing the electronic apparatus to transmit an ultrasonic signal, and causing the electronic apparatus to receive an ultrasonic detection signal.
In this step, the ratio of the distance between the reflection component and the electronic device to the operating wavelength of the ultrasonic wave may be greater than 10, so that the ultrasonic detection signal received by the electronic device mainly includes a static energy signal (for example, a direct ultrasonic signal and an internal leakage ultrasonic signal), the reflected ultrasonic signal is negligible, and the area 1 in fig. 5 shows the ultrasonic detection signal received by the electronic device in this step.
For example, for an ultrasonic application with an operating frequency of 20KHz, the distance between the reflecting component and the electronic device can be selected to be 15cm or more, and correspondingly, the length of the moving guide rail should be not less than 15cm, and the length, the width and the height of the closed sound insulation box body should be not less than 20 cm. In specific implementation, the contact part of the motion guide rail and the reflecting component can be subjected to surface treatment, so that impact noise or specific ultrasonic signals cannot be generated when the reflecting component slides on the motion guide rail, and the detection result of the ultrasonic reflection performance cannot be interfered.
S2, approaching the reflection member to the electronic device at a certain speed, causing the electronic device to emit an ultrasonic signal, and causing the electronic device to receive an ultrasonic detection signal.
In this step, the ultrasonic detection signal received by the electronic device mainly includes a static energy signal and a dynamic energy signal (which may also be understood as a dynamic reflected signal), and the area 2 in fig. 5 shows the ultrasonic detection signal received by the electronic device in this step.
In this step, the reflecting component can be moved closer to the electronic device at a slower speed to ensure that the interval between z1 and z2 corresponding to two adjacent second sampling periods t1 and t2 is far smaller than the wavelength of the ultrasonic signal, so as to better meet the assumption condition in formula (4). Illustratively, the close distance of the reflecting component relative to the electronic equipment can be 0cm/s-50cm/s, and under the conditions that the relative movement speed is 10cm/s, the ultrasonic emission frequency is 20KHz, and the second sampling period is 0.015ms, the position interval of the reflecting component under two adjacent second sampling periods is 1.5mm, which is far smaller than the wavelength of the ultrasonic signal.
In addition, in order to reduce the influence of air resistance on the detection result of the ultrasonic reflection performance, the ratio of the acoustic impedance of the reflection part to the acoustic impedance of air should be greater than 10, namely, one order of magnitude greater than the acoustic impedance of air.
S3, calculating the ultrasonic reflection performance of the electronic device according to the ultrasonic energy waveforms in the area 1 and the area 2 in fig. 5, wherein the calculation process is as follows:
(1) for region 1Averaging the ultrasonic energy in a plurality of first sampling periods in the ultrasonic energy signal, multiplying the average value by a preset coefficient, and calculating the energy average value
(2) Accumulating and summing the difference values of the ultrasonic energy squares between every two adjacent second sampling periods in a plurality of second sampling periods in the ultrasonic energy signals of the area 2 to calculate a characteristic value T;
(3) according to
And obtaining the relative size of the intensity A (N) of the reflected ultrasonic signal, and representing the ultrasonic reflection performance of the electronic equipment according to the relative size.
In addition, when the ultrasonic reflection performance detection system in fig. 2 or fig. 3 detects the ultrasonic reflection performance of the electronic device, the ultrasonic reflection surface of the reflection component and the ultrasonic emission surface of the electronic device should be aligned as much as possible to improve the ultrasonic reflection efficiency. Illustratively, the included angle between the reflecting surface of the reflecting component and the ultrasonic emitting surface of the electronic equipment can be 0-30 degrees.
In the present application, the electronic device includes, but is not limited to, a mobile phone, a tablet computer, a notebook computer, a palm computer, a vehicle-mounted terminal, a wearable device, a pedometer, and the like.
It should be noted that, in this document, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising an … …" does not exclude the presence of other like elements in a process, method, article, or apparatus that comprises the element.
Through the above description of the embodiments, those skilled in the art will clearly understand that the method of the above embodiments can be implemented by software plus a necessary general hardware platform, and certainly can also be implemented by hardware, but in many cases, the former is a better implementation manner. Based on such understanding, the technical solutions of the present application may be embodied in the form of a software product, which is stored in a storage medium (such as ROM/RAM, magnetic disk, optical disk) and includes instructions for enabling a terminal (such as a mobile phone, a computer, a server, an air conditioner, or a network device) to execute the method according to the embodiments of the present application.
While the present embodiments have been described with reference to the accompanying drawings, it is to be understood that the invention is not limited to the precise embodiments described above, which are meant to be illustrative and not restrictive, and that various changes may be made therein by those skilled in the art without departing from the spirit and scope of the invention as defined by the appended claims.
Claims (10)
1. An ultrasonic reflective performance detection system for testing ultrasonic performance of an electronic device, comprising:
sealing the box body;
the motion guide rail is arranged in the closed box body;
the reflecting component is connected with the motion guide rail in a sliding way;
the electronic equipment and the reflecting component are respectively positioned at two ends of the motion guide rail, and in the process that the electronic equipment and the reflecting component are close to each other, ultrasonic signals emitted by the electronic equipment are reflected by the reflecting component and received by the electronic equipment;
the electronic equipment determines the ultrasonic reflection performance of the electronic equipment through a first ultrasonic detection signal and a second ultrasonic detection signal, the first ultrasonic detection signal is an ultrasonic signal received by the electronic equipment when the reflection component is at a preset distance relative to the electronic equipment, and the second ultrasonic detection signal is an ultrasonic signal received by the electronic equipment in a process of approaching each other.
2. The system of claim 1, wherein an interior surface of the tank is coated with an ultrasound absorbing material.
3. The system of claim 1, wherein an included angle between the reflection surface of the reflection component and the ultrasound emission surface of the electronic device is 0-30 degrees.
4. The system of claim 1, wherein a ratio of acoustic impedance of the reflective member to acoustic impedance of air is greater than 10.
5. The system of claim 1, wherein the motion rail has a length of no less than 15 cm.
6. The system of claim 1, wherein the length, width and height of the box body are not less than 20 cm.
7. An ultrasonic reflection performance detection method applied to the ultrasonic reflection system according to claims 1-6, comprising:
when the reflecting component is located at a preset distance relative to the electronic equipment, the electronic equipment receives a first ultrasonic detection signal;
in the process that the reflecting component approaches to the electronic equipment from the preset distance, the electronic equipment receives a second ultrasonic detection signal;
the electronic equipment determines the ultrasonic reflection performance of the electronic equipment according to the first ultrasonic detection signal and the second ultrasonic detection signal.
8. The method of claim 7, wherein determining the ultrasonic reflective performance of the electronic device from the first ultrasonic detection signal and the second ultrasonic detection signal comprises:
calculating static signal energy according to the first ultrasonic detection signals of a plurality of continuous first sampling periods;
calculating dynamic signal energy according to the second ultrasonic detection signals of a plurality of continuous second sampling periods;
calculating a ratio of the dynamic signal energy and the static signal energy;
and determining the ultrasonic reflection performance of the electronic equipment according to the ratio.
9. The method of claim 8, wherein the static signal energy is a product of an energy average of the first ultrasonic detection signal corresponding to a plurality of the first sampling periods and a preset coefficient.
10. The method of claim 8, wherein the dynamic signal energy is a differential value of the energy squared of the second ultrasonic test signal corresponding to a plurality of the second sampling periods.
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| KR102383790B1 (en) * | 2015-05-22 | 2022-04-08 | 삼성전자주식회사 | Environment recognition method and electronic device thereof |
| US10746872B2 (en) * | 2018-05-18 | 2020-08-18 | Vadim Piskun | System of tracking acoustic signal receivers |
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Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN201345189Y (en) * | 2009-02-19 | 2009-11-11 | 复旦大学 | Ranging experimental instrument through audible sound waves |
| CN202710749U (en) * | 2012-07-18 | 2013-01-30 | 清华大学 | Radar target simulator based on CPCI basic framework |
| CN105718064A (en) * | 2016-01-22 | 2016-06-29 | 南京大学 | Gesture recognition system and method based on ultrasonic waves |
| CN209182496U (en) * | 2018-09-06 | 2019-07-30 | 珠海翔越电子有限公司 | A kind of detection device of digital radar probe |
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