A barometric pressure sensor calibration method, apparatus and barometric pressure sensor

Abstract

This invention discloses a method, apparatus, and pressure sensor calibration method for a barometric pressure sensor, comprising: determining the number of pressure calibration points and the pressure at each calibration point, wherein each calibration point corresponds to a standard frequency; acquiring the measured frequency output by the pressure sensor at each calibration point; obtaining a first frequency deviation for each calibration point based on the measured frequency and the standard frequency; performing polynomial curve fitting on each first frequency deviation and each calibration point to obtain the correspondence between the frequency deviation and the pressure; obtaining a second frequency deviation corresponding to the pressure at each measurement point of the pressure sensor based on the correspondence; and calibrating the frequency output by the pressure sensor at each measurement point based on the standard frequency and the second frequency deviation. This invention eliminates the need for manual calibration of the pressure sensor, improving the automation and efficiency of calibration, and the calibration process is more complete, thus improving calibration accuracy to a certain extent.

Description

Technical Field

[0001] This invention relates to the field of sensor detection technology, and in particular to a method, apparatus and a barometric pressure sensor calibration method. Background Technology

[0002] The barometric pressure sensor contains a magnetically conductive thin film, a spring, and a resonant circuit. When the barometric pressure drives the spring and the magnetically conductive thin film, they interact with the resonant circuit, thereby changing the output frequency of the resonant circuit. This frequency is then mapped to barometric pressure.

[0003] Currently, due to the uncertainty of the physical properties of components such as springs and magnetic films during the production process, the pressure sensors composed of them also have measurement error problems. Therefore, the pressure sensors need to be calibrated before leaving the factory.

[0004] Traditional calibration methods involve manually adjusting screws, potentiometers, and other components on the barometric pressure sensor after connecting it to a standard air source. This method is not highly automated and is inefficient. Even with existing technologies that automate barometric pressure sensor calibration through software, the calibration process is still not perfect, leading to some degree of inaccuracy. Summary of the Invention

[0005] This invention provides a method, apparatus, and barometric pressure sensor for calibration, in order to address the problem that existing methods for calibrating barometric pressure sensors have imperfect calibration processes, resulting in a certain degree of low calibration accuracy.

[0006] In a first aspect, the present invention provides a method for calibrating a barometric pressure sensor, comprising:

[0007] Determine the number of barometric pressure calibration points, the barometric pressure at each calibration point, and the standard frequency corresponding to each calibration point;

[0008] Obtain the measured frequency output by the barometric pressure sensor when measuring at the barometric pressure calibration point;

[0009] The first frequency deviation of the air pressure calibration point is obtained based on the measured frequency and the standard frequency corresponding to the air pressure calibration point.

[0010] Polynomial curve fitting is performed on each of the first frequency deviations and each of the air pressure calibration points to obtain the correspondence between frequency deviation and air pressure.

[0011] Based on the correspondence, the second frequency deviation corresponding to the air pressure at each measurement point of the air pressure sensor is obtained, and each measurement point corresponds to a standard frequency;

[0012] The frequency output by the barometric pressure sensor at the measurement point is calibrated based on the standard frequency corresponding to the measurement point and the second frequency deviation.

[0013] In a second aspect, the present invention provides a barometric pressure sensor calibration device, comprising:

[0014] The barometric pressure calibration point determination module is used to determine the number of barometric pressure calibration points and the barometric pressure at each barometric pressure calibration point. Each barometric pressure calibration point corresponds to a standard frequency.

[0015] The measured frequency acquisition module is used to acquire the measured frequency output by the barometric pressure sensor when it is measured at the barometric pressure calibration point.

[0016] The first frequency deviation determination module is used to obtain the first frequency deviation of the air pressure calibration point based on the measured frequency and the standard frequency corresponding to the air pressure calibration point.

[0017] The frequency deviation curve fitting module is used to perform polynomial curve fitting on each of the first frequency deviations and each of the air pressure calibration points to obtain the correspondence between frequency deviation and air pressure.

[0018] The second frequency deviation determination module is used to obtain the second frequency deviation corresponding to the air pressure at each measurement point of the air pressure sensor according to the correspondence relationship, and each measurement point corresponds to a standard frequency.

[0019] The calibration module is used to calibrate the frequency output by the barometric pressure sensor when measuring at the measurement point, based on the standard frequency corresponding to the measurement point and the second frequency deviation.

[0020] Thirdly, the present invention provides a pressure sensor, the pressure sensor comprising:

[0021] At least one processor; and

[0022] A memory communicatively connected to the at least one processor; wherein,

[0023] The memory stores a computer program that can be executed by the at least one processor to enable the at least one processor to perform the barometric pressure sensor calibration method according to the first aspect of the present invention.

[0024] The beneficial effects of the barometric pressure sensor calibration method of the present invention compared with the prior art are as follows:

[0025] In this embodiment, after determining the number of pressure calibration points and the pressure at each calibration point, the measured frequency output by the pressure sensor at each calibration point is obtained. Based on the measured frequency and standard frequency corresponding to each calibration point, the first frequency deviation of the pressure calibration point is obtained. Polynomial curve fitting is performed on each first frequency deviation and each calibration point to obtain the correspondence between frequency deviation and pressure. Based on the correspondence, the second frequency deviation corresponding to the pressure at each measurement point of the pressure sensor is obtained. Based on the standard frequency and second frequency deviation corresponding to the measurement point, the frequency output by the pressure sensor at each measurement point is calibrated. The embodiments of this invention not only help reduce manpower and material costs and improve calibration efficiency, but also, by using the measurement data of the air pressure calibration points and based on polynomial curve fitting, can obtain the frequency deviation of the air pressure at each measurement point within the measurement range in a relatively complete, fast and effective manner. The execution algorithm is not complicated and easy to implement. It can calibrate the output frequency by using the standard frequency and frequency deviation of each measurement point, which can reduce the problems of complicated procedures caused by the need for a lot of data for calibration, or the problem of insufficient data affecting measurement accuracy. The calibration process of this invention can easily obtain the measurement data of each measurement point of the air pressure sensor, thereby calibrating each measurement point. The calibration process is relatively complete and easy to operate, improving the degree of automation and calibration accuracy.

[0026] It should be understood that the description in this section is not intended to identify key or essential features of the embodiments of the present invention, nor is it intended to limit the scope of the invention. Other features of the invention will become readily apparent from the following description. Attached Figure Description

[0027] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0028] Figure 1 This is a flowchart of a barometric pressure sensor calibration method provided in Embodiment 1 of the present invention;

[0029] Figure 2 This is a flowchart of a barometric pressure sensor calibration method provided in Embodiment 2 of the present invention;

[0030] Figure 3 This is a schematic diagram of the structure of a barometric pressure sensor calibration device provided in Embodiment 3 of the present invention;

[0031] Figure 4 This is a schematic diagram of the structure of the air pressure sensor provided in Embodiment 4 of the present invention. Detailed Implementation

[0032] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of the present invention.

[0033] Currently, when calibrating barometric pressure sensors using software, the process typically involves calibrating only relatively commonly used pressure points, or calculating the average frequency deviation between a standard frequency and the measured frequencies of a few selected pressure points. During use, this average frequency deviation is used to correct the measured frequencies at the selected pressure points to achieve the standard frequency; for example, the sum of the measured frequency and the average frequency deviation is used as the output frequency. However, these calibration methods do not reflect the measurement error of the barometric pressure at every point across the entire measurement range of the sensor. Therefore, the calibration method is relatively coarse and incomplete, resulting in low calibration accuracy.

[0034] To address the shortcomings and low accuracy of existing calibration methods, the barometric pressure sensor calibration method provided by the embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

[0035] Example 1

[0036] Figure 1 This is a flowchart of a barometric pressure sensor calibration method provided in Embodiment 1 of the present invention. This embodiment is applicable to the calibration of barometric pressure sensors. The method can be executed by a barometric pressure sensor calibration device, which can be implemented in hardware and / or software. The barometric pressure sensor calibration device can be configured in the barometric pressure sensor, such as... Figure 1 As shown, the barometric pressure sensor calibration method includes:

[0037] S101. Determine the number of air pressure calibration points and the air pressure at each air pressure calibration point. Each air pressure calibration point corresponds to a standard frequency.

[0038] In this embodiment, when calibrating the pressure sensor, the pressure sensor is connected to a standard air source. The pressure of the standard air source gradually increases, and the pressure calibration point can be the pressure point where the pressure needs to be recorded during the gradual increase of the pressure of the standard air source.

[0039] In one embodiment, the barometric pressure sensor is calibrated to bring the deviation of the barometric pressure sensor to a desired value, thereby performing at least one calibration. After each calibration, the number of barometric pressure calibration points can be adjusted. The more barometric pressure calibration points there are, the higher the calibration accuracy. The number of barometric pressure calibration points can be initialized during the first calibration. This initial number can be an empirical value to reduce the number of calibrations.

[0040] After determining the number of pressure calibration points and obtaining the measurement range of the pressure sensor, the measurement range can be divided into multiple intervals based on the number of calibration points. The pressure value at the endpoint of each interval is then used to determine the pressure magnitude of the corresponding calibration point. For example, if the number of pressure calibration points is k, the measurement range can be divided into N intervals, where N = k-1. The endpoint of each interval is then designated as a pressure calibration point, and the pressure magnitude at each endpoint is the pressure magnitude of that calibration point.

[0041] For example, assuming the measurement range of the barometric pressure sensor is 0-12 kPa and k = 5, the measurement range of 0-10 kPa can be divided into 4 intervals, and the barometric pressure at the endpoint of each interval can be determined as the barometric pressure of the calibration point. That is, the barometric pressure of the 5 barometric pressure calibration points are 0 kPa, 3 kPa, 6 kPa, 9 kPa and 12 kPa.

[0042] The standard frequency can be the frequency output by the resonant circuit in the pressure sensor when the pressure sensor measures the true value of the pressure. In one embodiment, the output frequencies of multiple pressure sensors at multiple pressures under a preset temperature environment can be obtained, and the average frequency of the output frequency at each pressure can be calculated as the standard frequency corresponding to each pressure. By fitting the pressure-standard frequency curve with each standard frequency and each pressure, the standard frequency corresponding to each pressure can be obtained.

[0043] S102. Obtain the measured frequency output by the barometric pressure sensor when measuring at the barometric pressure calibration point.

[0044] When calibrating a barometric pressure sensor, connect the gas inlet of the barometric pressure sensor to the gas outlet of a standard gas source. Then, control the pressure of the standard gas source to gradually increase from 0, so that the standard gas source outputs a gradually increasing airflow to the barometric pressure sensor until the maximum range of the barometric pressure sensor is reached. During the pressure increase process, the frequency output by the barometric pressure sensor at each barometric pressure calibration point can be recorded as the measured frequency at each barometric pressure calibration point.

[0045] S103. Based on the measured frequency and standard frequency corresponding to the air pressure calibration point, obtain the first frequency deviation of the air pressure calibration point.

[0046] For each pressure calibration point, the difference between the measured frequency and the standard frequency at that pressure calibration point can be calculated to obtain the first frequency deviation of each pressure calibration point.

[0047] S104. Perform polynomial curve fitting on each first frequency deviation and each air pressure calibration point to obtain the correspondence between frequency deviation and air pressure.

[0048] After obtaining the first frequency deviation at each pressure calibration point, a polynomial curve fitting can be performed on the first frequency deviation and pressure magnitude at each pressure calibration point to obtain the correspondence between frequency deviation and pressure.

[0049] In one embodiment, a higher-order polynomial function can be constructed to perform polynomial curve fitting, obtain all coefficients of the polynomial function, and determine the final fitting function to obtain the correspondence between frequency deviation and air pressure based on the fitting function. Furthermore, during curve fitting, a fitting curve can be mapped based on the fitting function, where the horizontal axis represents air pressure and the vertical axis represents frequency deviation, thus obtaining the frequency deviation corresponding to each air pressure.

[0050] In another embodiment, the frequency deviation-pressure curve can also be obtained by linear or nonlinear fitting of the air pressure magnitude and the first frequency deviation at each air pressure calibration point. This embodiment does not limit the way of fitting the correspondence between the first frequency difference and the air pressure.

[0051] S105. Based on the correspondence, the second frequency deviation corresponding to the air pressure at each measurement point of the air pressure sensor is obtained, and each measurement point corresponds to a standard frequency.

[0052] After obtaining the correspondence between frequency deviation and air pressure, the frequency deviation corresponding to the air pressure at each measurement point within the measurement range of the air pressure sensor can be obtained through this correspondence. For example, when a curve is mapped based on the correspondence, the target point of each air pressure on the curve can be determined from the curve. The value of the vertical axis corresponding to the target point is the frequency deviation corresponding to each air pressure.

[0053] S106. Based on the standard frequency corresponding to the measurement point and the second frequency deviation, calibrate the frequency output by the barometric pressure sensor when measuring at the measurement point.

[0054] In one embodiment, for each measurement point, the sum of the deviations between the standard frequency and the second frequency at that measurement point can be calculated as the standard frequency corresponding to the air pressure at that measurement point. That is, the sum is used to replace the standard frequency in the pre-stored standard frequency-air pressure correspondence in the control chip to obtain a new standard frequency-air pressure correspondence.

[0055] In another embodiment, when the barometric pressure sensor measures the output frequency at the measurement point, the measured frequency can be increased by adding a frequency deviation to reach the standard frequency corresponding to the measurement point, thus eliminating the need to modify the correspondence between the standard frequency and barometric pressure in the control chip.

[0056] In this embodiment, after determining the number of pressure calibration points and the pressure at each calibration point, the measured frequency output by the pressure sensor at each calibration point is obtained. Based on the measured frequency and standard frequency corresponding to each calibration point, the first frequency deviation of the pressure calibration point is obtained. Polynomial curve fitting is performed on each first frequency deviation and each calibration point to obtain the correspondence between frequency deviation and pressure. Based on the correspondence, the second frequency deviation corresponding to the pressure at each measurement point of the pressure sensor is obtained. Based on the standard frequency and second frequency deviation corresponding to the measurement point, the frequency output by the pressure sensor at each measurement point is calibrated. The invention eliminates the need for manual mechanical calibration of the barometric pressure sensor, reducing labor and material costs and improving calibration efficiency. Furthermore, by using measurement data from barometric pressure calibration points and employing a polynomial curve fitting method, the frequency deviation of the barometric pressure at each measurement point within the measurement range can be obtained relatively completely, quickly, and effectively. The execution algorithm is simple and easy to implement, reducing the complexity of the calibration process required for large amounts of data, and minimizing the impact on measurement accuracy due to insufficient data acquisition. The calibration process of this invention facilitates the acquisition of measurement data at each measurement point of the barometric pressure sensor, enabling calibration at each measurement point. The calibration process is relatively complete and easy to operate, improving automation and calibration accuracy.

[0057] Example 2

[0058] Figure 2 This is a flowchart of a barometric pressure sensor calibration method provided in Embodiment 2 of the present invention. This embodiment optimizes Embodiment 1 as described above. Figure 2 As shown, the barometric pressure sensor calibration method includes:

[0059] S201. Determine the number of air pressure calibration points and the air pressure at each air pressure calibration point. Each air pressure calibration point corresponds to a standard frequency.

[0060] In this embodiment, after connecting the pressure sensor to the standard air source, the number of pressure calibration points can be initialized, and the pressure of each pressure calibration point can be determined by the number of pressure calibration points.

[0061] In one embodiment, after determining the number of pressure calibration points and obtaining the measurement range of the pressure sensor, the measurement range can be divided into multiple intervals based on the number of calibration points. The pressure value at the endpoint of each interval is then used to determine the pressure magnitude of the corresponding calibration point. For example, if the number of pressure calibration points is k, the measurement range can be divided into N intervals, where N = k-1. The endpoint of each interval is then defined as a pressure calibration point, and the pressure magnitude corresponding to that endpoint is the pressure magnitude of the corresponding calibration point.

[0062] S202. Obtain the measured frequency output by the barometric pressure sensor when measuring at the barometric pressure calibration point.

[0063] Specifically, the pressure of the standard gas source can be controlled to gradually increase from 0, so that the pressure sensor connected to the standard gas source outputs the measured frequency. During the pressure increase, the frequency output by the pressure sensor at each pressure calibration point can be recorded as the measured frequency at each pressure calibration point.

[0064] S203. Based on the measured frequency and standard frequency corresponding to the air pressure calibration point, obtain the first frequency deviation of the air pressure calibration point.

[0065] For each pressure calibration point, the difference between the measured frequency and the standard frequency at that pressure calibration point can be calculated to obtain the first frequency deviation of each pressure calibration point.

[0066] S204. Perform polynomial curve fitting on each first frequency deviation and each air pressure calibration point to obtain the correspondence between frequency deviation and air pressure.

[0067] In this embodiment, the correspondence can be a fitting function of a higher-order polynomial, which is as follows:

[0068]

[0069] In the above formula (1), δf χ (P k This indicates that the barometric pressure sensor operates at pressure P. k The frequency deviation at k pressure calibration points is then calculated. For a given pressure sensor, after obtaining the first frequency deviation at k pressure calibration points, it is substituted into the above formula (1) to obtain the following equation:

[0070]

[0071] Solving the above equations yields the coefficients (A0 A1…A) of the higher-order polynomials. k ) T .

[0072] S205. Based on the correspondence, the second frequency deviation corresponding to the air pressure at each measurement point of the air pressure sensor is obtained, and each measurement point corresponds to a standard frequency.

[0073] As shown in formula (1) above, the coefficients (A0 A1…A) of the higher-order polynomial are solved. k ) T Substituting the air pressure at each measurement point into formula (1), we can obtain the second frequency deviation corresponding to the air pressure at each measurement point.

[0074] S206. Obtain the preset expected value and the measurement range of the barometric pressure sensor.

[0075] The preset expected value can be the measurement error of the barometric pressure sensor, which is the design error caused by the components of the barometric pressure sensor itself. The measurement range, i.e. the range of the barometric pressure sensor, is related to the structure and electrical properties of the barometric pressure sensor. The measurement range and the preset expected value can be stored in the memory of the barometric pressure sensor in advance.

[0076] S207. Based on the deviations of each second frequency within the measurement range, obtain the average frequency deviation within the measurement range.

[0077] Specifically, the average frequency deviation within the measurement range can be obtained using the following formula:

[0078]

[0079] In the above formula P represents the average frequency deviation. min P is the minimum air pressure that the barometer can measure. max A is the maximum air pressure that the barometer can measure. i represents the coefficients of the fitting function, and k represents the number of pressure calibration points.

[0080] S208, The average frequency deviation did not meet the expected value.

[0081] After obtaining the average frequency deviation, it can be determined whether the frequency deviation has reached the expected value. If the average frequency deviation has not reached the expected value, return to S201 to determine the number of pressure calibration points, that is, adjust the number of pressure calibration points to recalibrate the pressure sensor. For example, the number of pressure calibration points can be gradually increased from small to large. When the number of pressure calibration points is small, the average frequency deviation may be greater than the expected value, which indicates that the calibration accuracy is low. The number of pressure calibration points can be increased until the average frequency deviation reaches the expected value. Or, if the average frequency deviation is much smaller than the expected value, the calibration accuracy is too high, and the number of calibration points can be reduced.

[0082] S209, The average frequency deviation has reached the expected value.

[0083] When the average frequency deviation reaches the expected value, it is determined that the calibration accuracy is sufficient, the number of selected air pressure calibration points is appropriate, and the parameters of the air pressure sensor can be calibrated. Then, execute S210.

[0084] S210. Based on the standard frequency corresponding to the measurement point and the second frequency deviation, calibrate the frequency output by the barometric pressure sensor when measuring at the measurement point.

[0085] In one embodiment, for each measurement point, the sum of the deviations between the standard frequency and the second frequency at that measurement point can be calculated, as follows:

[0086]

[0087] The sum is the standard frequency corresponding to the calibrated air pressure P. δf is the standard frequency of the stored air pressure P before calibration. χ (P) represents the second frequency deviation corresponding to air pressure P. The calculated sum can be used to replace the standard frequency in the pre-stored standard frequency-air pressure correspondence in the control chip to obtain a new standard frequency-air pressure correspondence.

[0088] In another embodiment, when the barometric pressure sensor measures the output frequency at the measurement point, the measured frequency can be increased by adding a frequency deviation to reach the standard frequency corresponding to the measurement point, thus eliminating the need to modify the correspondence between the standard frequency and barometric pressure in the control chip.

[0089] In this embodiment, after determining the number of pressure calibration points and the pressure at each calibration point, the measured frequency output by the pressure sensor at each calibration point is obtained. Then, a first frequency deviation is determined by comparing the measured frequency at the calibration point with a standard frequency. A polynomial curve fitting is performed on each first frequency deviation and each calibration point to obtain the correspondence between frequency deviation and pressure. Based on this correspondence, a second frequency deviation corresponding to the pressure at each measurement point of the pressure sensor is obtained. Each measurement point corresponds to a standard frequency. A preset expected value and the measurement range of the pressure sensor are obtained. Based on the second frequency deviations within the measurement range, the average frequency deviation within the measurement range is obtained. If the average frequency deviation does not reach the expected value, the number of pressure calibration points is re-determined for recalibration. If the average frequency deviation reaches the expected value, the frequency output by the pressure sensor at each measurement point is calibrated based on the standard frequency and the second frequency deviation corresponding to the measurement point. This invention eliminates the need for manual mechanical calibration of the barometric pressure sensor, reducing labor and material costs and improving calibration efficiency. Furthermore, by using measurement data from barometric pressure calibration points and employing a polynomial curve fitting method, it can obtain the frequency deviation of the barometric pressure at each measurement point within the measurement range in a relatively complete, rapid, and effective manner. Its execution algorithm is simple and easy to implement, enabling calibration of the output frequency using the standard frequency and frequency deviation of each measurement point. This reduces the complexity of calibration procedures requiring large amounts of data, and the problem of insufficient data affecting measurement accuracy. The calibration process of this invention facilitates the acquisition of measurement data from each measurement point of the barometric pressure sensor, thereby calibrating each measurement point. During the calibration process, the average frequency deviation is also calculated, and if the average frequency deviation does not reach the expected value, the number of barometric pressure calibration points is recalculated for recalibration. The calibration process is relatively complete and easy to operate, improving automation and calibration accuracy.

[0090] Example 3

[0091] Figure 3 This is a schematic diagram of a barometric pressure sensor calibration device provided in Embodiment 3 of the present invention. Figure 3 As shown, the barometric pressure sensor calibration device may specifically include:

[0092] The bar pressure calibration point determination module 301 is used to determine the number of bar pressure calibration points and the bar pressure of each bar pressure calibration point. Each bar pressure calibration point corresponds to a standard frequency.

[0093] The measured frequency acquisition module 302 is used to acquire the measured frequency output by the barometric pressure sensor when measuring at the barometric pressure calibration point;

[0094] The first frequency deviation determination module 303 is used to obtain the first frequency deviation of the air pressure calibration point based on the measured frequency and the standard frequency corresponding to the air pressure calibration point.

[0095] The frequency deviation curve fitting module 304 is used to perform polynomial curve fitting on each of the first frequency deviations and each of the air pressure calibration points to obtain the correspondence between frequency deviation and air pressure.

[0096] The second frequency deviation determination module 305 is used to obtain the second frequency deviation corresponding to the air pressure at each measurement point of the air pressure sensor according to the correspondence relationship, and each measurement point corresponds to a standard frequency.

[0097] The calibration module 306 is used to calibrate the frequency output by the barometric pressure sensor when measuring at the measurement point, based on the standard frequency corresponding to the measurement point and the second frequency deviation.

[0098] Optionally, it also includes:

[0099] The expected value and measurement range acquisition module is used to acquire the preset expected value and the measurement range of the air pressure sensor;

[0100] The average frequency deviation determination module is used to obtain the average frequency deviation within the measurement range based on the second frequency deviations within the measurement range.

[0101] The first average frequency deviation judgment module is used to return to the air pressure calibration point determination module if the average frequency deviation does not reach the expected value.

[0102] Optionally, it also includes:

[0103] The second average frequency deviation judgment module is used to execute the second frequency deviation determination module 305 if the average frequency deviation reaches the expected value.

[0104] Optionally, the air pressure calibration point determination module 301 includes:

[0105] The number determination unit is used to determine the number of air pressure calibration points;

[0106] A measurement range acquisition unit is used to acquire the measurement range of the air pressure sensor;

[0107] The air pressure determination unit is used to divide the measurement range into multiple intervals on an average basis according to the number of air pressure calibration points, and determine the air pressure of the air pressure calibration point based on the air pressure value at the endpoint of each interval.

[0108] Optionally, the correspondence is a fitting function of a higher-order polynomial, and the average frequency deviation determination module includes:

[0109] The average frequency deviation calculation unit is used to obtain the average frequency deviation within the measurement range according to the following formula:

[0110]

[0111] In the above formula P represents the average frequency deviation. min P is the minimum air pressure that the barometer can measure. max A is the maximum air pressure that the barometer can measure. i represents the coefficients of the fitting function, and k represents the number of pressure calibration points.

[0112] Optionally, the calibration module 306 includes:

[0113] An output frequency calibration unit is used to take the sum of the standard frequency and the deviation of the second frequency as the frequency output when measuring the measurement point.

[0114] Optionally, it also includes a standard frequency acquisition module, used to acquire the output frequencies of multiple pressure sensors when measuring multiple pressures under a preset temperature environment; calculate the average frequency of the output frequency of each pressure; and obtain the standard frequency corresponding to each pressure by fitting a pressure-standard frequency curve with the average frequency and the pressure.

[0115] The barometric pressure sensor calibration device provided in this embodiment of the invention can execute the barometric pressure sensor calibration method provided in any embodiment of the invention, and has the corresponding functional modules and beneficial effects of the method.

[0116] Example 4

[0117] Figure 4 A schematic diagram of the structure of a pressure sensor 40 that can be used to implement an embodiment of the present invention is shown. Figure 4 As shown, the barometric pressure sensor 40 includes at least one processor 41 and a memory, such as a read-only memory (ROM) 42 or a random access memory (RAM) 43, communicatively connected to the at least one processor 41. The memory stores computer programs executable by the at least one processor 41. The processor 41 can perform various appropriate actions and processes based on the computer program stored in the ROM 42 or loaded from storage unit 48 into the RAM 43. The RAM 43 may also store various programs and data required for the operation of the barometric pressure sensor 40. The processor 41, ROM 42, and RAM 43 are interconnected via a bus 44. An input / output (I / O) interface 45 is also connected to the bus 44.

[0118] Multiple components in the pressure sensor 40 are connected to the I / O interface 45, including: a control panel 46, such as a panel on the pressure sensor 40 including buttons, a touch screen, etc.; and a communication unit 47, such as a wireless communication transceiver. The communication unit 47 allows the pressure sensor 40 to exchange information / data with other devices through computer networks such as the Internet and / or various telecommunications networks.

[0119] Processor 41 can be a variety of general-purpose and / or special-purpose processing components with processing and computing capabilities. Some examples of processor 41 include, but are not limited to, a central processing unit (CPU), various special-purpose artificial intelligence (AI) computing chips, various processors running machine learning model algorithms, digital signal processors (DSPs), and any suitable processor, controller, microcontroller, etc. Processor 41 performs the various methods and processes described above, such as barometric pressure sensor calibration methods.

[0120] In some embodiments, the barometric pressure sensor calibration method can be implemented as a computer program, and in some embodiments, part or all of the computer program can be loaded and / or mounted on the barometric pressure sensor 40 via ROM 42 and / or communication unit 47. When the computer program is loaded into RAM 43 and executed by processor 41, one or more steps of the barometric pressure sensor calibration method described above can be performed. Alternatively, in other embodiments, processor 41 can be configured to perform the barometric pressure sensor calibration method by any other suitable means (e.g., by means of firmware).

[0121] Various implementations of the systems and techniques described above in this document can be implemented in digital electronic circuit systems, integrated circuit systems, field-programmable gate arrays (FPGAs), application-specific integrated circuits (ASICs), application-specific standard products (ASSPs), systems-on-a-chip (SOCs), complex programmable logic devices (CPLDs), computer hardware, firmware, software, and / or combinations thereof.

[0122] Computer programs used to implement the methods of the present invention may be written in any combination of one or more programming languages. These computer programs may be provided to a processor such that, when executed by the processor, the functions / operations specified in the flowcharts and / or block diagrams are performed. The computer programs may be executed entirely on a machine, partially on a machine, as a standalone software package partially on a machine and partially on a remote machine, or entirely on a remote machine or server.

[0123] It should be understood that the various forms of processes shown above can be used, with steps reordered, added, or deleted. For example, the steps described in this invention can be executed in parallel, sequentially, or in different orders, as long as the desired result of the technical solution of this invention can be achieved, and this is not limited herein.

[0124] The specific embodiments described above do not constitute a limitation on the scope of protection of this invention. Those skilled in the art should understand that various modifications, combinations, sub-combinations, and substitutions can be made according to design requirements and other factors. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this invention should be included within the scope of protection of this invention.

Claims

1. A method for calibrating a barometric pressure sensor, characterized in that, include: Determine the number of barometric pressure calibration points, the barometric pressure at each calibration point, and the standard frequency corresponding to each calibration point; Obtain the measured frequency output by the barometric pressure sensor when measuring at the barometric pressure calibration point; Based on the measured frequency and standard frequency corresponding to the air pressure calibration point, the first frequency deviation of the air pressure calibration point is obtained, and the first frequency deviation is the difference between the measured frequency and the standard frequency. Polynomial curve fitting is performed on each of the first frequency deviations and each of the air pressure calibration points to obtain the correspondence between frequency deviation and air pressure, wherein the correspondence is a fitting function of a higher-order polynomial. Substituting the air pressure at each measurement point within the measurement range of the air pressure sensor into the fitting function yields the second frequency deviation corresponding to the air pressure at each measurement point of the air pressure sensor, with each measurement point corresponding to a standard frequency; The frequency output by the barometric pressure sensor at the measurement point is calibrated based on the standard frequency corresponding to the measurement point and the second frequency deviation.

2. The barometric pressure sensor calibration method as described in claim 1, characterized in that, Before calibrating the frequency output by the barometric pressure sensor at the measurement point based on the standard frequency corresponding to the measurement point and the second frequency deviation, the method further includes: Obtain the preset expected value and the measurement range of the air pressure sensor; The average frequency deviation within the measurement range is obtained based on the second frequency deviations within each measurement range. If the average frequency deviation does not reach the expected value, return to the step of determining the number of barometric pressure calibration points.

3. The barometric pressure sensor calibration method as described in claim 2, characterized in that, Also includes: If the average frequency deviation reaches the expected value, the frequency output by the barometric pressure sensor at the measurement point is calibrated according to the standard frequency corresponding to the measurement point and the second frequency deviation.

4. The barometric pressure sensor calibration method as described in claim 1, characterized in that, Determine the number of barometric pressure calibration points and the barometric pressure at each calibration point, including: Determine the number of barometric calibration points; Obtain the measurement range of the air pressure sensor; The measurement range is divided into multiple intervals on an average basis according to the number of air pressure calibration points, and the air pressure of the air pressure calibration point is determined according to the air pressure value at the endpoint of each interval.

5. The barometric pressure sensor calibration method as described in claim 2, characterized in that, The correspondence is a fitting function of a higher-order polynomial, and the average frequency deviation within the measurement range is obtained according to the following formula: In the above formula P represents the average frequency deviation. min P is the minimum air pressure that the barometer can measure. max A is the maximum air pressure that the barometer can measure. i represents the coefficients of the fitting function, and k represents the number of pressure calibration points.

6. The barometric pressure sensor calibration method according to any one of claims 1-5, characterized in that, Based on the standard frequency corresponding to the measurement point and the second frequency deviation, the frequency output by the barometric pressure sensor when measuring at the measurement point is calibrated, including: The sum of the standard frequency and the deviation of the second frequency is used as the output frequency when measuring the measurement point.

7. The barometric pressure sensor calibration method according to any one of claims 1-5, characterized in that, The standard frequency for each air pressure is determined in the following way: Obtain the output frequencies of multiple pressure sensors when measuring multiple pressures under a preset temperature environment; Calculate the average frequency of the output frequency for each air pressure, and use it as the standard frequency for each air pressure; fit the air pressure-standard frequency curves with each standard frequency and each air pressure to obtain the standard frequency for each air pressure.

8. A barometric pressure sensor calibration device, characterized in that, include: The barometric pressure calibration point determination module is used to determine the number of barometric pressure calibration points and the barometric pressure at each barometric pressure calibration point. Each barometric pressure calibration point corresponds to a standard frequency. The measured frequency acquisition module is used to acquire the measured frequency output by the barometric pressure sensor when it is measured at the barometric pressure calibration point. The first frequency deviation determination module is used to obtain the first frequency deviation of the air pressure calibration point based on the measured frequency and the standard frequency corresponding to the air pressure calibration point. The first frequency deviation is the difference between the measured frequency and the standard frequency. The frequency deviation curve fitting module is used to perform polynomial curve fitting on each of the first frequency deviations and each of the air pressure calibration points to obtain the correspondence between frequency deviation and air pressure, wherein the correspondence is a fitting function of a higher-order polynomial. The second frequency deviation determination module is used to substitute the air pressure at each measurement point within the measurement range of the air pressure sensor into the fitting function to obtain the second frequency deviation corresponding to the air pressure at each measurement point of the air pressure sensor, and each measurement point corresponds to a standard frequency. The calibration module is used to calibrate the frequency output by the barometric pressure sensor when measuring at the measurement point, based on the standard frequency corresponding to the measurement point and the second frequency deviation.

9. The barometric pressure sensor calibration device as described in claim 8, characterized in that, Also includes: The expected value and measurement range acquisition module is used to acquire the preset expected value and the measurement range of the air pressure sensor; The average frequency deviation determination module is used to obtain the average frequency deviation within the measurement range based on the second frequency deviations within the measurement range. The average frequency deviation judgment module is used to return to the air pressure calibration point determination module if the average frequency deviation does not reach the expected value.

10. A barometric pressure sensor, characterized in that, The pressure sensor includes: At least one processor; and A memory communicatively connected to the at least one processor; wherein, The memory stores a computer program that can be executed by the at least one processor to enable the at least one processor to perform the barometric pressure sensor calibration method according to any one of claims 1-7.

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