CN113765517A - High-precision multichannel synchronous acquisition system for temperature adaptive calibration - Google Patents
High-precision multichannel synchronous acquisition system for temperature adaptive calibration Download PDFInfo
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- H03M1/00—Analogue/digital conversion; Digital/analogue conversion
- H03M1/06—Continuously compensating for, or preventing, undesired influence of physical parameters
- H03M1/08—Continuously compensating for, or preventing, undesired influence of physical parameters of noise
- H03M1/089—Continuously compensating for, or preventing, undesired influence of physical parameters of noise of temperature variations
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Abstract
The invention discloses a high-precision multichannel synchronous acquisition system for temperature self-adaptive calibration, which comprises: the device comprises an AD converter, a DSP, an FPGA, an operational amplifier, an analog switch and a thermistor; analog signals output by an external component are connected to the input end of an analog switch, the output end of the analog switch is connected to the input end of an operational amplifier, the output end of the operational amplifier is connected to the input end of an AD converter, and R/C, CS signals of the AD converter are simultaneously controlled by an FPGA (field programmable gate array) so as to realize the synchronous acquisition of multi-channel analog quantity signals; the temperature calibration channel signal is obtained by pulling up a thermistor in the system through a voltage stabilizing source, and the output temperature voltage signal is connected to the input end of the other analog switch; analog signals collected by the AD converter are sent to the FPGA after being subjected to AD conversion, the FPGA communicates with the DSP through an EMIF interface of the DSP, collected temperature calibration signals and analog signals of external components are sent to the DSP, and the DSP processes the analog signals of the external components according to a temperature self-adaptive calibration algorithm.
Description
Technical Field
The invention relates to the fields of signal acquisition, data processing and temperature self-calibration, in particular to a high-precision multichannel synchronous acquisition system for temperature self-adaptive calibration.
Background
Data acquisition is an important way for intelligent measurement, data analysis and control systems to acquire information. The accuracy of the data acquisition is critical to the performance of the overall system. The acquisition precision is related to a functional chip used by the system, and a high-performance control processing chip and a high-precision AD conversion chip are the basis for realizing high-precision data acquisition. However, due to the non-ideality of the device, certain errors exist in the data acquired by the system, and the performance index of the whole system is affected. Typical errors of devices such as AD converters include offset error, gain error, integral non-linearity INL and differential non-linearity DNL. The offset error and the gain error are adjusted to be minimum when the components are delivered from a factory, and the integral non-linearity INL and the differential non-linearity DNL can be corrected by a hardware or software calibration method. However, due to the influence of temperature and environmental noise changes, these errors will change to different degrees, and the conventional error compensation method often cannot achieve the expected acquisition accuracy during full-scale acquisition. In addition, the temperature drift characteristics of the components cause certain loss to the data acquisition precision.
Under the influence of temperature, the application environment of the acquisition system is limited due to the change of the error characteristics of components, and the high-precision acquisition system applied to the satellite-borne equipment must meet the requirement of ensuring the same acquisition precision in a complicated space environment of minus dozens to plus dozens of degrees centigrade, so a reasonable temperature calibration method must be designed for the high-precision acquisition system to correct the influence of temperature on acquired data so as to meet the performance index requirement of the whole system.
Disclosure of Invention
The invention aims to provide a high-precision multichannel synchronous acquisition system with temperature self-adaptive calibration, which can self-adaptively adjust calibration coefficients in different temperature environments, simultaneously compensate offset errors, gain errors, INL, DNL and errors caused by temperature drift of the system, and achieve the aim of acquiring precision superior to 1mV in a wider acquisition range (0-10V) in high and low temperature (-20-55 ℃) environments.
In order to achieve the above object, the present invention provides a high-precision multichannel synchronous acquisition system with adaptive temperature calibration, comprising: the device comprises an AD converter, a DSP, an FPGA, an operational amplifier, an analog switch and a thermistor;
analog signals output by an external component are connected to the input end of an analog switch, the output end of the analog switch is connected to the input end of an operational amplifier, the output end of the operational amplifier is connected to the input end of an AD converter, and R/C, CS signals of the AD converter are simultaneously controlled by an FPGA (field programmable gate array) so as to realize synchronous acquisition of multi-channel analog quantity signals; the temperature calibration channel signal is obtained by pulling up a thermistor in the system through a voltage stabilizing source, and the output temperature voltage signal is connected to the input end of the other analog switch;
the FPGA realizes asynchronous acquisition of different external component signals and acquisition of temperature calibration channel signals by controlling the gating time sequence of the control end of the analog switch;
analog quantity signals collected by the AD converter are sent to the FPGA after being subjected to AD conversion, the FPGA communicates with the DSP through an EMIF interface of the DSP, collected temperature calibration signals and analog quantity signals of external components are sent to the DSP, and the DSP processes the analog quantity signals of the external components according to a temperature self-adaptive calibration algorithm.
In the high-precision multichannel synchronous acquisition system for temperature adaptive calibration, the AD converter acquires analog signals of different external components in a time-sharing manner by switching the analog switch; the DSP is responsible for realizing a temperature self-adaptive calibration algorithm; the FPGA is responsible for multi-channel acquisition channel control, time sequence control and interrupt management.
The high-precision multichannel synchronous acquisition system for temperature adaptive calibration is characterized in that a voltage follower circuit realized by an operational amplifier is arranged between the analog switch and the AD converter, and the voltage follower circuit has higher input impedance and lower output impedance and is used for impedance matching of analog acquisition so as to reduce the influence of impedance on an acquisition loop on acquisition precision.
The high-precision multichannel synchronous acquisition system with the temperature self-adaptive calibration function is characterized in that the AD976ASD chip is selected as the AD converter, and the AD976ASD chip has 16-bit resolution and +/-10V measuring range.
The high-precision multichannel synchronous acquisition system with the temperature self-adaptive calibration function is characterized in that the input end of the AD converter is connected with a capacitor with the power of 300-400 PF; two groups of capacitors to ground are connected in parallel between a digital power supply and an analog power supply of the AD converter, and an 'x' type single-point short circuit mode is adopted, wherein a 200nF ceramic dielectric capacitor is used for filtering interference of partial high-frequency signals, and a 22uF tantalum capacitor is used for reducing influence generated by partial low-frequency interference signals.
The high-precision multichannel synchronous acquisition system with the temperature self-adaptive calibration function is characterized in that the operational amplifier is OP27AJ, and the operational amplifier is a follower circuit.
The high-precision multichannel synchronous acquisition system with the temperature self-adaptive calibration function is characterized in that the analog switch is HI 1-201.
The high-precision multichannel synchronous acquisition system for temperature adaptive calibration is characterized in that the temperature adaptive calibration algorithm is realized by using a 32-bit floating-point chip DSP, and the model is SMJ320C6701GLPW 14.
The high-precision multichannel synchronous acquisition system with the temperature self-adaptive calibration function comprises a calibration channel system hardware platform, a temperature range and a sampling range are subdivided according to the specific application environment of acquisition equipment, the calibration coefficient of each temperature section is calculated according to a calibration algorithm model, and the calibration coefficient of each temperature section is applied to the system hardware platform.
A temperature self-adaptive calibration algorithm comprises the steps of firstly determining a calibration mathematical model, then subdividing a sampling range and a temperature range, and finally determining a temperature calibration channel; the external environment temperature is collected by a system temperature channel, the temperature channel is realized by a thermistor in the system, and a temperature signal is converted into an analog quantity voltage signal; the multichannel synchronous acquisition system acquires a group of temperature channel signals inside the system before acquiring the analog signals of the external components each time, so that the temperature environment of the external analog quantity signals is judged according to the signals, and the used calibration coefficients are determined.
The temperature self-calibration system provided by the patent is realized by adopting a framework mode of DSP + FPGA + AD converter. And 4 AD converters are adopted to acquire analog signals of different external components in a time-sharing manner by switching the analog switches. Simultaneous acquisition of 4-channel signals can be performed for the same external component. The hardware structure of the multichannel acquisition system is shown in figure 1.
The DSP is mainly responsible for realizing the temperature self-adaptive calibration algorithm. The FPGA is mainly responsible for multi-channel acquisition channel control, time sequence control, interrupt management and the like. A voltage follower circuit realized by an operational amplifier is arranged between the multi-path gating analog switch and the A/D device, and the voltage follower circuit has higher input impedance and lower output impedance and is used for impedance matching of analog quantity acquisition so as to reduce the influence of impedance (internal resistance of an external component, cable loss, internal resistance of the analog switch and the like) on acquisition precision on an acquisition loop.
The selection of the AD analog-to-digital converter is crucial to the acquisition precision of the whole system, an AD976ASD chip with high reliability of aerospace products is selected for the system, and the AD976ASD has 16-bit resolution and +/-10V measuring range. In order to reduce the influence of external noise on the acquired signal and ensure the accuracy and reliability of the acquisition circuit, a hardware filtering measure as shown in fig. 2 is adopted for the AD analog-to-digital converter. In fig. 2, a signal from the output end of the operational amplifier to the input end of the AD analog-to-digital converter may generate a certain degree of jitter, and a capacitor of 300PF to 400PF is added to the input end to eliminate the jitter; two groups of capacitors to ground are connected in parallel between a digital power supply and an analog power supply of the AD analog-to-digital converter, wherein a ceramic capacitor of 200nF is used for filtering interference of partial high-frequency signals, and a tantalum capacitor of 22uF can reduce the influence generated by partial low-frequency interference signals. The AGND and the DGND of the AD analog-digital converter adopt an 'x' type single-point short circuit mode to reduce the influence of digital system noise on an analog system and simultaneously have certain improvement effect on the stability and the precision of data acquisition. The hardware filtering measure proposed by the patent based on the AD976ASD is also applicable to AD converters of other models.
Under high and low temperature environments, the external precise voltage reference adopted by the operational amplifier, the AD converter and the AD converter is mainly used for generating temperature drift of component parameters in the system. Wherein, the temperature drift of the operational amplifier is about 0.2 uV/DEG C; a typical value for AD976ASD is 7 ppm/c, i.e., normalized to +25 c with zero error and an output voltage of seven parts per million from its nominal value for every 1 c change in temperature. The standard value adopted by the AD976ASD in the collection system designed by the patent is 2.5V, and the AD976ASD output voltage deviates 17.5uV when the temperature changes by 1 ℃. As can be seen from the temperature drift characteristic curve of AD976ASDA, the deviation of about 1mV is generated at 0 ℃ in AD976 ASD; the output error of the precision voltage reference device is usually +/-25 mV, the temperature drift is usually 55 ppm/DEG C, the precision voltage reference device is influenced by the reference voltage drift, and the error of 3 mV-4 mV of data acquired by AD976ASD is generated at 0 ℃.
In order to correct the offset and gain and INL and DNL errors in high and low temperature environments and achieve high-precision data acquisition, the patent provides a temperature self-adaptive calibration algorithm, and the algorithm firstly needs to determine a calibration mathematical model.
Calibration model
The proportion of linear errors existing in a data acquisition system is generally far greater than that of nonlinear errors, and the data acquisition system is easy to calibrate, so that the existing calibration method aims at the linear errors of the system, and the calibration method provided by the patent is also based on the linear errors of the system.
In the graph shown in fig. 3, the X-axis is the actual collected value and the Y-axis is the desired value (input value). The ideal conversion curve equation for data acquisition is: and y is x.
And the slope of the actual transfer curve is ktIntercept of btAnd the actual conversion data of the system corresponding to any point input x is marked as y. Then y is kix+hi。
By (x) on the ideal transfer curve0，y0) The points are used as reference points, and a fitting curve equation of the system can be established by an actual conversion equation:
y′-y0＝k′t(x′-x0)+b′t
2 calibration reference point coordinates (x) on the actual conversion curvec，yc)，(xd，yd) The coefficients k 'of the fitting curves can be obtained by substituting the coefficients into the above formulae'tAnd b'tThe value of (c):
sampling range and temperature range subdivision
(1) Sampling range subdivision
As shown in fig. 3, generally, 0, 1/2FSR and 1FSR 3 reference points are selected for calibration on the X-axis, and if more precise calibration is to be achieved, the X-axis needs to be further subdivided as shown below.
The 0-1/2 FSR section can be subdivided into: (1/2n) FSR ( n 1,2,3 … … i), obtained using a calibration model (k)1、 b1)，(k2、b2)……(ki、bi) i calibration coefficients.
1/2FSR 1FSR section can be subdivided into: (1-1/2n) FSR (n ═ 1,2,3 … … i); (k) is also obtained using the calibration model1、b1)，(k2、b2)……(ki、bi) i calibration coefficients.
(2) Subdivision of temperature range
Suppose the operating temperature of the system is T0～TnThe temperature gradient interval is set to Δ t (Δ t)<(|Tn|-|T0I))) at Ti～TiAnd (3) subdividing the sampling range of the temperature segment of + delta t (i is 0,1, …, n) to obtain the calibration coefficient of each acquisition range segment of the temperature segment.
The working temperature range of the collection system designed by the patent is-20-55 ℃, and the temperature gradient interval delta t can be subdivided into 10 ℃, 5 ℃ or 1 ℃. For example, the temperature gradient interval Δ t is 1 ℃. Namely, within the temperature range of-20 ℃ to 55 ℃, a calibration coefficient is used for every 1 ℃ change of temperature.
According to the characteristics of the calibration model, the more accurate the subdivision of the acquisition range and the temperature range is, the higher the accuracy of the acquired data is.
Temperature calibration channel
The external environment temperature is collected by a system temperature channel, the temperature channel is realized by a thermistor in the system, and the temperature signal is converted into an analog quantity voltage signal. The multichannel synchronous acquisition system that this patent was realized gathers the inside temperature channel signal of a set of system before the analog signal of external component is gathered at every turn, and the temperature environment of outside analog quantity signal is decided to the signal from this to decide the calibration coefficient who uses. The temperature calibration channel is shown in dashed outline in fig. 1.
Fig. 5 shows the maximum absolute error versus temperature of the input values versus the actual sampled values at different acquisition stages. As can be seen from the figure, the acquisition errors of the acquisition signals of the 4 channels of the acquisition system are less than 1mV in different sampling ranges and different temperatures, and the purpose of high-precision acquisition in a wider sampling range (0V-10V) and a higher temperature range (-20 ℃ -55 ℃) is realized.
As can be seen from the three-dimensional change trend graph of input voltage-temperature-error of fig. 6, the input voltage is in the range of 0V to 10V, and the acquisition error is changed in a trend of "increase first, then decrease, then increase second, then decrease", which indicates that the acquisition system designed in the patent has a strong adaptive energy-saving capability; within the temperature range of-20 ℃ to 55 ℃, the collected signals can be corrected according to the calibration coefficient of each temperature section, so that the collection error is less than 1mV, and the system has strong environmental adaptability.
Compared with the prior art, the invention has the technical beneficial effects that:
the multichannel acquisition system has the advantages that acquisition errors of multichannel acquisition signals are smaller than 1mV in different sampling ranges and different temperatures, and the purpose of high-precision acquisition in a wider sampling range (0V-10V) and a higher temperature range (-20 ℃ -55 ℃) is achieved.
The acquisition system designed by the patent has strong adaptive capacity, and can correct the acquired signals according to the calibration coefficients of all temperature sections within the temperature range of-20-55 ℃ so that the acquisition error is less than 1mV, which indicates that the system has strong environment adaptive capacity.
Drawings
The invention discloses a high-precision multichannel synchronous acquisition system for temperature self-adaptive calibration, which is provided by the following embodiments and attached drawings.
Fig. 1 is a hardware structure diagram of a multi-channel synchronous acquisition system.
Fig. 2 is a hardware connection diagram of an AD converter AD976ASD circuit.
Fig. 3 is a timing diagram of data acquisition during a single acquisition cycle.
FIG. 4 is a calibration model graph.
Fig. 5 is a graph showing the relationship between the maximum absolute error of the input value and the actual sampling value and the temperature at different acquisition stages.
Fig. 6 is a three-dimensional variation trend graph of input voltage-temperature-error.
Fig. 7 is a table of calibration coefficients for a first acquisition channel over different temperature ranges and acquisition ranges.
Detailed Description
The present invention will be described in further detail with reference to the accompanying drawings.
The temperature self-calibration multichannel synchronous acquisition system designed by the patent firstly needs to build a hardware platform with a calibration channel system. And then subdividing the temperature range and the sampling range according to the specific application environment of the acquisition equipment, and solving the calibration coefficient of each temperature section according to the calibration algorithm model. And finally, applying the calibration coefficients of the temperature sections to a system hardware platform.
1. Construction of multi-channel synchronous acquisition system hardware platform with system calibration channel
As shown in fig. 1. The hardware platform is realized by adopting an architecture mode of FPGA + DSP + AD converter. The AD converter selects 4 AD976 ASDs, the precision voltage reference selects 1 AD580RH, the operational amplifier selects 4 OP27AJ, the analog switch selects 3 HI1-201, the temperature calibration algorithm is realized by using 32bit floating point type core DSP, and the model selects SMJ320C6701GLPW 14. The components required by the device are conventional general components of aerospace or ground products, and other devices with the same type and the same characteristics can be selected for replacement. Four paths of analog signals output by the external component 1 are connected to the input end of one piece of HI1-201(4 input 4 output 4 control end); four paths of analog signals output by the external component 2 are connected to the input ends of another HI 1-201; temperature calibration channel signals are obtained by pulling up a thermistor MF501 in the system through a voltage stabilizing source by 2.5V, and output temperature voltage signals are connected to the input end of a third HI 1-201. And four control terminals of each HI1-201 are respectively connected with one IO port of the FPGA. The output end of the three HIs 1-201 is connected to the input end of the four operational amplifiers, the operational amplifiers are designed to be follower circuits, the output ends of the operational amplifiers are connected to the input ends of the four AD976 ASDs, and R/C, CS signals of the four AD976 ASDs are simultaneously controlled by the FPGA to realize synchronous acquisition of four-channel analog quantity signals. The FPGA realizes asynchronous acquisition of different external component signals and acquisition of temperature calibration channel signals by controlling the gating time sequence of the control end of the three analog switches HI1-201, and the gating time sequence is shown in figure 3. Analog quantity signals collected by four AD976 ASDs are sent to the FPGA after being subjected to AD conversion, the FPGA communicates with the DSP through an EMIF interface of the DSP, collected temperature calibration signals and analog quantity signals of external components are sent to the DSP, and the DSP processes the analog quantity signals of the external components according to a temperature self-calibration algorithm.
In order to reduce INL, DNL, offset error, gain error and acquisition error caused by external interference during AD conversion, AD976ASD hardware filtering measures are designed with reference to fig. 2. The voltage-stabilizing signal generated by the precision voltage reference source AD580 is connected to the REF end of the AD976ASD, and a precision resistance value of 33.2k omega is connected to the REF end and the input end, and the resistance value of the precision voltage reference source AD976ASD is not changed due to compensation resistance during analog-to-digital conversion operation. The input end is connected with a ground capacitor of 300PF to 400 PF; two groups of capacitors to ground are connected in parallel between the digital power supply and the analog power supply, and a star-shaped single-point short circuit mode is adopted.
According to the acquisition sequence of acquiring the temperature signal in the system, acquiring the first four-channel analog quantity signal of the external component 1 and then acquiring the four-channel analog quantity signal of the external component 2, taking a group of temperature signal, the four-channel signal of the external component 1 and the four-channel signal of the external component 2 as an acquisition period, wherein a data acquisition time sequence table in a single acquisition period is shown in figure 3,
in FIG. 3, J0、J1Acquisition of channel gating signals for analog voltages, Z0Channel gating signals are collected for temperature. Firstly, Z is0Put into effect, gating the temperature acquisition channel, Z0The effective time is about 300 us; then enters a gate-disabled state 100us, with the aim of avoiding mutual crosstalk between the signals at the instant the gating switches are turned off and on; then "J" is introduced0The method comprises the following steps of setting to be effective, collecting external first group of analog quantity signals, wherein the effective time is about 700 us; then entering a gate-inhibited state 100 us; finally J is put1And setting to be effective, and acquiring an external second group of analog quantity signals, wherein the effective time is about 700 us. The effective time of the gating signal can be determined according to the acquisition frequency requirement of actual engineering on the analog quantity.
2. Temperature range and sampling range subdivision
And (3) subdividing a sampling range: the patent selects 0, 1/2FSR (marked as X)c) 3/4FSR (denoted as X)d) And 1FSR (noted X)f) And calibrating the four reference points.
The temperature range is subdivided: this patent temperature gradient interval delta t chooses for use 5 ℃. I.e. one calibration factor is used per 5 deg.c change in temperature.
3. Determining a calibration model
The patent selects 0, 1/2FSR (marked as X)c) 3/4FSR (denoted as X)d) And 1FSR (noted X)f) And calibrating the four reference points.
0-1/2 FSR section:
1/2 FSR-3/4 FSR section:
3/4FSR section 1FSR section:
4. Determination and application of calibration coefficients
Firstly, carrying out high-low temperature (-20-55 ℃) environment tests on an acquisition system without a calibration coefficient, measuring the temperature once at every 5 ℃ change to obtain original acquisition data in different temperatures, and taking the data as an actual acquisition value (figure 4X axis); the expected values (FIG. 4Y-axis) were measured on a digital table of FLUKE45 (0.1 mV accuracy) at different temperatures. And then, obtaining a calibration coefficient by using the calibration model in each sampling range. The calibration coefficients for the first acquisition channel are shown in fig. 7. In fig. 7, a temperature calibration channel is first determined from temperature data collected from the system content; and then determining a sampling range according to the analog quantity voltage signal acquired by the external acquisition channel. The KB calibration coefficients of the analog signal can be determined from the temperature calibration channel and the acquisition range. The collection system of this patent sets up four synchronous collection passageways, because the influence factor of gathering passageway external environment and internal environment is inconsistent, so need set up different calibration coefficients to four passageways. However, since the calibration coefficients of other channels are consistent with the first channel design method, the details of this patent are not repeated.
And finally, storing the calibration coefficient of the figure 7 in a DSP of a system hardware platform to form a multi-channel synchronous acquisition system with the calibration coefficient. When the system is applied to collection again, the DSP judges an environment temperature section according to the collected data of the temperature channel, and adaptively calls the calibration coefficient under the temperature section to realize the temperature adaptive calibration of the collected data. The acquired data of each temperature section calibrated by the calibration coefficient is infinitely close to the measured value of FLUKE45, and the purpose that the acquisition error of each temperature section is less than 1mV is achieved.
Claims (10)
1. A high-precision multichannel synchronous acquisition system for temperature adaptive calibration is characterized by comprising: the device comprises an AD converter, a DSP, an FPGA, an operational amplifier, an analog switch and a thermistor;
analog signals output by an external component are connected to the input end of an analog switch, the output end of the analog switch is connected to the input end of an operational amplifier, the output end of the operational amplifier is connected to the input end of an AD converter, and R/C, CS signals of the AD converter are simultaneously controlled by an FPGA (field programmable gate array) so as to realize the synchronous acquisition of multi-channel analog quantity signals; the temperature calibration channel signal is obtained by pulling up a thermistor in the system through a voltage stabilizing source, and the output temperature voltage signal is connected to the input end of the other analog switch;
the FPGA realizes asynchronous acquisition of different external component signals and acquisition of temperature calibration channel signals by controlling the gating time sequence of the control end of the analog switch;
analog quantity signals collected by the AD converter are sent to the FPGA after being subjected to AD conversion, the FPGA communicates with the DSP through an EMIF interface of the DSP, collected temperature calibration signals and analog quantity signals of external components are sent to the DSP, and the DSP processes the analog quantity signals of the external components according to a temperature self-adaptive calibration algorithm.
2. The system according to claim 1, wherein the AD converter time-divisionally acquires analog signals of different external components by switching the analog switch; the DSP is responsible for realizing a temperature self-adaptive calibration algorithm; the FPGA is responsible for multi-channel acquisition channel control, time sequence control and interrupt management.
3. The system of claim 1, wherein a voltage follower circuit implemented by an operational amplifier is disposed between the analog switch and the AD converter, and the voltage follower circuit has a higher input impedance and a lower output impedance for impedance matching of analog acquisition to reduce the influence of impedance on the acquisition loop on the acquisition accuracy.
4. The system of claim 1, wherein the AD converter is an AD976ASD chip, and the AD976ASD chip has a 16-bit resolution and a ± 10V range.
5. The system according to claim 4, wherein the input end of the AD converter is connected with a capacitor of 300-400 PF; two groups of capacitors to ground are connected in parallel between a digital power supply and an analog power supply of the AD converter, and an 'x' type single-point short circuit mode is adopted, wherein a 200nF ceramic capacitor is used for filtering interference of partial high-frequency signals, and a 22uF tantalum capacitor is used for reducing influence generated by partial low-frequency interference signals.
6. The system of claim 1, wherein the operational amplifier is OP27AJ, and the operational amplifier is a follower circuit.
7. A high-precision multichannel synchronous acquisition system with adaptive temperature calibration as claimed in claim 1, characterized in that the analog switch is HI 1-201.
8. The system of claim 1, wherein the temperature adaptive calibration algorithm is implemented by using a 32-bit floating-point type chip DSP, and the model is SMJ320C6701GLPW 14.
9. The high-precision multichannel synchronous acquisition system for the temperature adaptive calibration according to claim 1 is characterized in that a hardware platform with a calibration channel system is required to be built, then a temperature range and a sampling range are subdivided according to the specific application environment of the acquisition equipment, the calibration coefficient of each temperature section is calculated according to a calibration algorithm model, and finally the calibration coefficient of each temperature section is applied to the system hardware platform.
10. The temperature adaptive calibration algorithm of the high-precision multichannel synchronous acquisition system based on claim 1 is characterized in that a calibration mathematical model is firstly determined, then a sampling range and a temperature range are subdivided, and finally a temperature calibration channel is determined; the external environment temperature is collected by a system temperature channel, the temperature channel is realized by a thermistor in the system, and a temperature signal is converted into an analog quantity voltage signal; the multichannel synchronous acquisition system acquires a group of temperature channel signals inside the system before acquiring the analog signals of the external components each time, so that the temperature environment of the external analog quantity signals is judged according to the signals, and the used calibration coefficients are determined.
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114362754A (en) * | 2022-03-21 | 2022-04-15 | 成都凯天电子股份有限公司 | Multichannel analog signal acquisition and processing system |
| CN116879855A (en) * | 2023-09-05 | 2023-10-13 | 成都梓峡信息技术有限公司 | Radar electronic countermeasure signal processing system and method |
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Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114362754A (en) * | 2022-03-21 | 2022-04-15 | 成都凯天电子股份有限公司 | Multichannel analog signal acquisition and processing system |
| CN114362754B (en) * | 2022-03-21 | 2022-06-07 | 成都凯天电子股份有限公司 | Multichannel analog signal acquisition and processing system |
| CN116879855A (en) * | 2023-09-05 | 2023-10-13 | 成都梓峡信息技术有限公司 | Radar electronic countermeasure signal processing system and method |
| CN116879855B (en) * | 2023-09-05 | 2023-11-28 | 成都梓峡信息技术有限公司 | Radar electronic countermeasure signal processing system and method |
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