CN113108867B - A segmented coaxial guided wave radar level gauge data processing method - Google Patents

Abstract

The invention discloses a data processing method of a segmented guided wave radar liquid level meter. The method comprises the following steps: predicting a predicted value of the liquid level height in the target container at the next measurement according to the measured liquid level value and the liquid level change speed value of the current liquid level height in the target container; calculating a first false echo signal in the first echo signal measured next time according to the predicted value and the length of each segment of the waveguide rod; acquiring a first echo signal of a wave guide rod when liquid in a target container is positioned at the predicted liquid level height; calculating an initial measured level value of the predicted liquid level height according to the first echo signal and the first false echo signal; and performing Kalman filtering processing on the initial measurement liquid level value to obtain a measurement liquid level value of the predicted liquid level height. The present disclosure also provides a data processing system, a storage medium, and a computer program product of a segmented guided wave radar level gauge.

Description

A segmented coaxial guided wave radar level gauge data processing method

technical field

The invention belongs to the technical field of FMCW radar liquid level gauge signal processing, and in particular relates to a data processing method, data processing system, storage medium and computer program product of a segmented guided wave radar liquid level gauge.

Background technique

The FMCW system guided wave radar level gauge is a radar level gauge instrument based on the principle of frequency domain reflection (FDR). The frequency-modulated continuous wave electromagnetic signal of the radar level gauge propagates along the probe. At the same time, part of the signal of the radar level gauge is reflected to form an echo and returns to the signal transmitting device (receiving antenna) along the same path. The received echo signal and the coupled signal of the transmitted signal are mixed to generate a difference frequency signal. Converted to frequency difference, measuring frequency instead of directly measuring time difference to calculate liquid level height.

Depending on the structure of the probe, the commonly used guided wave radar level gauges include two types: coaxial type and double-rod type. Among them, the coaxial probe is the most basic and most effective probe in the guided wave radar level gauge. , The electromagnetic signal propagates in the space between the metal rod and the metal round tube, the energy is concentrated, and will not spread, which can effectively propagate high-frequency signals, and is not easily affected by the outside world.

The traditional coaxial probe adopts an integrated structure. Because the length of the rod structure is restricted, it is not easy to transport and install, so the coaxial probe is not suitable for large ranges. In order to overcome this limitation, the coaxial probe can adopt a segmented structure, and each segment is connected by a thread to achieve a larger range, and at the same time, it is convenient for transportation and installation.

In the process of realizing the concept of the present disclosure, the inventor found that the characteristic impedance at the connection of each segment of the segmented coaxial probe is not continuous with other parts, and false echoes will be generated at the connection, which will interfere with the liquid level measurement, resulting in There is a problem of large measurement error.

SUMMARY OF THE INVENTION

In view of this, the present disclosure provides a data processing method for a segmented coaxial guided wave radar liquid level gauge.

One aspect of the present disclosure provides a method for processing segmented coaxial guided wave radar liquid level gauge data, including:

According to the measured liquid level value and the liquid level change speed value of the current liquid level height in the target container, predict the predicted value of the liquid level height in the target container during the next measurement;

Calculate the first false echo signal in the next measured first echo signal according to the predicted value and the length of each section of the probe;

acquiring the first echo signal of the probe when the liquid in the target container is at the predicted liquid level;

Calculate the measured liquid level value of the predicted liquid level according to the first echo signal and the first false echo signal;

Kalman filtering is performed on the liquid level value to obtain the measured liquid level value of the predicted liquid level height.

According to an embodiment of the present disclosure, the data processing method further includes:

respectively acquiring the background echo signal of the probe when there is no liquid in the target container and the initial echo signal of the probe when the liquid in the target container is at the initial liquid level height;

The measured liquid level value and the liquid level change speed value of the initial liquid level height are calculated according to the background echo signal and the initial echo signal.

According to an embodiment of the present disclosure, the acquisition of the background echo signal of the probe when there is no liquid in the target container and the initial echo signal of the probe when the liquid in the target container is at an initial liquid level height is performed respectively. The echo signal includes:

respectively collecting the second echo signal of the probe when there is no liquid in the target container and the third echo signal of the probe when the liquid in the target container is at the initial liquid level;

The second echo signal and the third echo signal are respectively subjected to chirp Z-transform to obtain the background echo signal and the initial echo signal.

According to an embodiment of the present disclosure, the background echo signal includes:

c(t)=c ₀ (t)+c ₁ (t)+c ₂ (t)+…+c _Q (t)

Among them, c(t) is the background echo signal, c ₀ (t) is the reflected signal caused by the impedance mismatch of the probe feed port, c ₁ (t) is the length from the probe feed port L ₁ The reflected signal generated at the connection between the first section of the probe and the second section of the probe, c ₂ (t) is the second section of the probe and the third section of the length L ₂ from the probe feed port The reflected signal generated at the connection of the probe, c _Q (t) is the total reflection signal caused by the short-circuit at the end of the Q-th section of the probe with a length of L _Q from the probe feed port.

According to an embodiment of the present disclosure, the calculation of the measured liquid level value and the liquid level change speed value of the initial liquid level height according to the background echo signal and the initial echo signal includes:

obtaining a second false echo signal at the feeding port of the probe according to the background echo signal;

Eliminate the false echo signal in the initial echo signal according to the second false echo signal to obtain a first real echo signal;

The first real echo signal is processed by the method of wave peak positioning to obtain the initial liquid level height value;

The liquid level change speed value is calculated according to the initial liquid level value.

According to an embodiment of the present disclosure, according to the measured liquid level value of the current liquid level in the target container, predicting the predicted value of the liquid level in the target container for the next measurement includes:

为测量液位值，

为相邻两次测量的液位变化速度值，T为相邻两次测量的时间间隔。in,

To measure the liquid level value,

is the liquid level change speed value of two adjacent measurements, and T is the time interval of two adjacent measurements.

According to an embodiment of the present disclosure, the calculating, according to the predicted value and the length of each section of the probe, the first false echo signal in the first echo signal to be measured next time includes:

为第一虚假回波信号，C_i(k)为距离导波杆馈电端口的长度为L_i的第i段导波杆和第i+1段导波杆连接处产生的反射信号，J为预测值至馈电端口间导波杆的分段数，L_J≤X＜L_J+1，X为预测值。in

is the first false echo signal, C _i (k) is the reflected signal generated at the junction of the _i -th section of the probe and the i+1-th section of the probe with a length of Li from the probe feed port, J is the segment number of the probe between the predicted value and the feeding port, L _J ≤ X<L _J+1 , X is the predicted value.

According to an embodiment of the present disclosure, the acquiring the first echo signal of the probe when the liquid in the target container is at a predicted liquid level includes:

collecting the fourth echo signal of the probe when the liquid in the target container is at the predicted liquid level;

The chirp-z-transform is performed on the fourth echo signal within a window centered on the predicted value to obtain the first echo signal.

According to an embodiment of the present disclosure, calculating the measured liquid level value of the predicted liquid level according to the first echo signal and the first false echo signal includes:

Eliminate the false echo signal in the first echo signal according to the first false echo signal to obtain a second true echo signal;

The second real echo signal is processed by the method of wave peak positioning to obtain the initial measured liquid level value of the predicted liquid level height.

According to an embodiment of the present disclosure, performing Kalman filtering processing on the initial measured liquid level value to obtain the measured liquid level value of the predicted liquid level includes:

Kalman filtering is performed on the initial measured liquid level value to obtain the measured liquid level value of the predicted liquid level height in the target container and the liquid level change speed value in the target container;

The measured liquid level value is output as the final output result.

According to the embodiment of the present disclosure, the false echo signal in the echo signal of the next measurement can be calculated by the predicted value of the liquid level height in the target container and the length of each section of the probe in the next measurement, and then according to the false echo signal. The echo signal calculates the real echo signal of each measurement, which can eliminate the influence of the false echo caused by the discontinuous impedance at the feed port and the connection of each probe on the measurement result, and effectively improve the measurement accuracy. At the same time, the present disclosure can reduce the influence of external interference or instantaneous liquid level jitter on the measurement by performing Kalman filtering processing on the liquid level value, and further improve the measurement accuracy.

Description of drawings

FIG. 1 schematically shows a flowchart of a data processing method for a segmented guided wave radar liquid level gauge according to an embodiment of the present disclosure.

FIG. 2 schematically shows a schematic diagram of a background echo signal according to an embodiment of the present disclosure.

FIG. 3 schematically shows a schematic diagram of an initial echo signal according to an embodiment of the present disclosure.

FIG. 4 schematically shows a schematic diagram of a first real echo signal according to an embodiment of the present disclosure.

FIG. 5 schematically shows a schematic diagram of the relationship between the measured value and the real value of the data processing method according to an embodiment of the present disclosure.

FIG. 6 schematically shows a schematic diagram of the error between the measured value and the actual value of the data processing method according to an embodiment of the present disclosure.

7 schematically illustrates a block diagram of a data processing system according to an embodiment of the present disclosure.

FIG. 8 schematically shows a block diagram of a computer system suitable for implementing a data processing method according to an embodiment of the present disclosure.

Detailed ways

In order to make the objectives, technical solutions and advantages of the present invention more clearly understood, the present invention will be further described in detail below in conjunction with specific embodiments and with reference to the accompanying drawings.

The terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the present disclosure. The terms "comprising", "comprising" and the like as used herein indicate the presence of stated features, steps, operations and/or components, but do not preclude the presence or addition of one or more other features, steps, operations or components.

All terms (including technical and scientific terms) used herein have the meaning as commonly understood by one of ordinary skill in the art, unless otherwise defined. It should be noted that terms used herein should be construed to have meanings consistent with the context of the present specification and should not be construed in an idealized or overly rigid manner.

In the process of realizing the present disclosure, the inventor found that the characteristic impedance at the connection of each segment of the segmented coaxial probe is not continuous with other parts, and false echoes will be generated at the connection, which will interfere with the liquid level measurement, resulting in the occurrence of The problem of large measurement error.

In view of the above problems, the present disclosure provides a data processing method, data processing system, storage medium and computer program product of a segmented guided wave radar liquid level gauge.

FIG. 1 schematically shows a flowchart of a data processing method for a segmented guided wave radar liquid level gauge according to an embodiment of the present disclosure.

As shown in FIG. 1 , the data processing method for a segmented guided wave radar liquid level gauge provided by an embodiment of the present disclosure includes operations S101 to S105 .

In operation S101, a predicted value of the liquid level in the target container in the next measurement is predicted according to the measured liquid level value and the liquid level change speed value of the current liquid level in the target container.

In operation S102, a first false echo signal among the first echo signals to be measured next time is calculated according to the predicted value and the length of each section of the probe.

According to the embodiment of the present disclosure, since the segmented coaxial guided wave radar liquid level gauge will cause false echoes at the feed port and the connection of each probe due to discontinuous impedance, which will affect the measurement results, it is necessary to first Calculate the false echo signal in the echo signal in the next measurement.

According to the embodiment of the present disclosure, for example, the predicted value of the liquid level height in the target container is located in the middle of the i+1-th section of the probe in the next measurement. At this time, before the next measurement, the i-th section of the guided wave needs to be predicted The reflected signal generated at the connection between the rod and the i+1 section of the probe, the reflected signal generated at each connection at the upper end of the i section of the probe, and the segmented coaxial guided wave radar level gauge generated at the feed port Reflect the signal, and calculate the false echo signal in the echo signal in the next measurement according to all the above reflected signals.

In operation S103, a first echo signal of the probe when the liquid in the target container is at the predicted liquid level is acquired.

According to an embodiment of the present disclosure, the predicted liquid level may be the actual liquid level of the liquid in the target container at the next measurement as described above. Since the predicted liquid level height may have errors with the actual liquid level height of the liquid in the target container during measurement, the value of the predicted liquid level height is different from the predicted value of the liquid level height in the target container described above.

In operation S104, an initial measured liquid level value of the predicted liquid level is calculated according to the first echo signal and the first false echo signal.

In operation S105, Kalman filtering is performed on the initial measured liquid level value to obtain the measured liquid level value of the predicted liquid level height.

According to the embodiment of the present disclosure, the false echo signal in the echo signal of the next measurement can be calculated by the predicted value of the liquid level height in the target container and the length of each section of the probe in the next measurement, and then according to the false echo signal. The echo signal calculates the real echo signal of each measurement, which can eliminate the influence of the false echo caused by the discontinuous impedance at the feed port and the connection of each probe on the measurement result, and effectively improve the measurement accuracy. At the same time, the present disclosure can reduce the influence of external interference or instantaneous liquid level jitter on the measurement by performing Kalman filtering processing on the liquid level value, and further improve the measurement accuracy.

According to an embodiment of the present disclosure, the data processing method may further include:

Obtain the background echo signal of the probe when there is no liquid in the target container and the initial echo signal of the probe when the liquid in the target container is at the initial liquid level; calculate the initial liquid according to the background echo signal and the initial echo signal. The measured liquid level value of the surface height and the value of the liquid level change speed.

According to an embodiment of the present disclosure, the background echo signals may include, for example, reflected signals caused by impedance mismatches at the connections of adjacent probes, at the feed port, and at the end of the last probe.

According to an embodiment of the present disclosure, the background echo signal includes:

c(t)=c ₀ (t)+c ₁ (t)+c ₂ (t)+…+c _Q (t) (1)

Among them, c(t) is the background echo signal, c ₀ (t) is the reflected signal caused by the impedance mismatch of the probe feed port, c ₁ (t) is the length from the probe feed port L ₁ The reflected signal generated at the connection between the first section of the probe and the second section of the probe, c ₂ (t) is the second section of the probe and the third section of the length L ₂ from the probe feed port The reflected signal generated at the connection of the probe, c _Q (t) is the total reflection signal caused by the short-circuit at the end of the Q-th section of the probe with a length of L _Q from the probe feed port.

According to the embodiment of the present disclosure, the segmented coaxial guided wave radar level gauge has four sections of probes, the first section of the probe is connected to the feed port through a flange, and the length is 1.2m, and the remaining three sections are guided Taking the probe length of 1m as an example, the background echo signal of the probe when there is no liquid in the target container is expressed as follows:

c(t)=c ₀ (t)+c ₁ (t)+c ₂ (t)+c ₃ (t)+c ₄ (t) (2)

Among them, c ₀ (t) is the reflected signal caused by the impedance mismatch of the feed port of the probe, the length L ₁ =0 from the mismatch point to the feed port, and c ₁ (t) is the distance from the feed port of the probe to the feed port. The reflected signal generated at the connection of the first section of the probe with the length of L ₁ =1.2m and the second section of the probe, c ₂ (t) is the distance from the feed port of the probe with a length of L ₂ =2.2m The reflected signal generated at the connection of the second section of the probe and the third section of the probe, c ₃ (t) is the third section of the probe and the fourth section of the probe with a length L ₃ =3.2m from the feed port of the probe The reflected signal generated at the connection of the section probe, c ₄ (t) is the total reflection signal caused by the short circuit at the end of the fourth section of the probe, and the length L ₄ =4.2m from the end of the probe to the feed port.

According to an embodiment of the present disclosure, respectively acquiring the background echo signal of the probe when there is no liquid in the target container and the initial echo signal of the probe when the liquid in the target container is at the initial liquid level may include:

Collect the second echo signal of the probe when there is no liquid in the target container and the third echo signal of the probe when the liquid in the target container is at the initial liquid level; The wave signal is subjected to linear frequency modulation Z-transformation to obtain the background echo signal and the initial echo signal.

According to an embodiment of the present disclosure, the second echo signal may be, for example, the raw data collected by the segmented coaxial guided wave radar level gauge when there is no liquid in the target container, and the third echo signal may be, for example, the The raw data collected by the type coaxial guided wave radar when the liquid in the target container is at the initial liquid level. The final background echo signal and the initial echo signal are obtained respectively by performing chirp-z-transform on the second echo signal and the third echo signal.

According to an embodiment of the present disclosure, performing chirp-Z-transform on the second echo signal and the third echo signal includes:

Among them, N is the number of acquisition points of echo data, M is the total number of spectrum analysis points, and C _i (k) is the spectrum of the echo signal C _i (n); where M is determined by the distance measurement accuracy requirements.

FIG. 2 schematically shows a schematic diagram of a background echo signal according to an embodiment of the present disclosure.

According to an embodiment of the present disclosure, as shown in FIG. 2 , the abscissa is the distance, and the ordinate is the amplitude. The segmented coaxial guided wave radar level gauge has four sections of probes. The first section of the probe is connected to the feed port through the flange, with a length of 1.2m, and the length of the remaining three sections is 1m. example. The total number of spectral sampling points M=131072. C ₀ (k) of the background echo signal is a waveform between -50cm and 100cm, C ₁ (k) is a waveform between 100cm and 140cm, C ₂ (k) is a waveform between 200cm and 240cm, and C ₃ (k ) is a waveform between 310cm and 330cm.

FIG. 3 schematically shows a schematic diagram of an initial echo signal according to an embodiment of the present disclosure.

According to the embodiment of the present disclosure, the segmented coaxial guided wave radar level gauge has four sections of probes, the first section of the probe is connected to the feed port through a flange, and the length is 1.2m, and the remaining three sections are guided The wave rod length is 1m as an example. The total number of spectral sampling points M=131072. The initial echo signal with the real initial liquid level height value of 40.4cm is shown in Figure 3. In the figure, the abscissa is the distance, and the ordinate is the amplitude. It can be seen from FIG. 3 that since the first real echo signal and the reflected signal generated at the feeding port are mixed together, the measurement error is relatively large.

According to an embodiment of the present disclosure, calculating the measured liquid level value and the liquid level change speed value of the initial liquid level height according to the background echo signal and the initial echo signal may include:

The second false echo signal at the feeding port of the probe is obtained according to the background echo signal; the false echo signal in the initial echo signal is eliminated according to the second false echo signal, and the first real echo signal is obtained; The positioning method processes the first real echo signal to obtain the initial liquid level height value; calculates the liquid level change speed value according to the initial liquid level height value.

According to the embodiment of the present disclosure, the first real echo signal is processed by the method of wave peak positioning, and the initial liquid level height value obtained includes:

为初始液面高度值，S₀(k)-C₀(k)为第一真实回波信号，S₀(k)为初始回波信号，C₀(k)为第二虚假回波信号，T为扫频时宽，B为扫频带宽，c为电磁波在真空中传播速度，f_s为接收采样频率，M为频谱采样总点数。in,

is the initial liquid level value, S ₀ (k)-C ₀ (k) is the first real echo signal, S ₀ (k) is the initial echo signal, C ₀ (k) is the second false echo signal, T is the sweep time width, B is the sweep bandwidth, c is the propagation speed of electromagnetic waves in a vacuum, f _s is the receiving sampling frequency, and M is the total number of spectrum sampling points.

FIG. 4 schematically shows a schematic diagram of a first real echo signal according to an embodiment of the present disclosure.

As shown in Figure 4, the abscissa is the distance, and the ordinate is the amplitude. The segmented coaxial guided wave radar level gauge has four sections of probes. The first section of the probe is connected to the feed port through the flange, with a length of 1.2m, and the length of the remaining three sections is 1m. example. The total number of spectral sampling points M=131072. The real initial liquid level value is 40.4 cm, and the first real echo signal is processed according to the method of wave peak positioning, and the obtained initial liquid level value is 40.38 cm.

According to an embodiment of the present disclosure, according to the measured liquid level value of the current liquid level in the target container, the predicted value of the liquid level in the target container for the next measurement is predicted to include:

为测量液位值，

为相邻两次测量的液位变化速度值，T为相邻两次测量的时间间隔。in,

To measure the liquid level value,

is the liquid level change speed value of two adjacent measurements, and T is the time interval of two adjacent measurements.

According to an embodiment of the present disclosure, calculating the first false echo signal in the next measured first echo signal according to the predicted value and the length of each section of the probe includes:

为第一虚假回波信号，C_i(k)为距离导波杆馈电端口的长度为L_i的第i段导波杆和第i+1段导波杆连接处产生的反射信号，J为预测值至馈电端口间导波杆的分段数，L_J≤X＜L_J+1，X为预测值。in,

is the first false echo signal, C _i (k) is the reflected signal generated at the junction of the _i -th section of the probe and the i+1-th section of the probe with a length of Li from the probe feed port, J is the segment number of the probe between the predicted value and the feeding port, L _J ≤ X<L _J+1 , X is the predicted value.

According to an embodiment of the present disclosure, acquiring the first echo signal of the probe when the liquid in the target container is at the predicted liquid level may include:

Collect the fourth echo signal of the probe when the liquid in the target container is at the predicted liquid level; perform chirp Z transformation on the fourth echo signal in the window centered on the predicted value to obtain the first echo signal.

According to the embodiments of the present disclosure, in order to reduce the amount of calculation, the spectrum can be calculated in the range of k, where:

Among them, w is the spectral calculation window.

According to an embodiment of the present disclosure, the width of w may include, for example, 20 cm, 25 cm, etc., and may also be other widths according to implementation needs.

According to an embodiment of the present disclosure, calculating the initial measured liquid level value of the predicted liquid level according to the first echo signal and the first false echo signal may include:

Eliminate the false echo signal in the first echo signal according to the first false echo signal to obtain the second true echo signal; process the second true echo signal by the method of wave peak positioning to obtain the predicted liquid level height Initially measure the liquid level value.

According to the embodiment of the present disclosure, the second real echo signal is processed by the method of wave peak positioning, and the measured liquid level value of the predicted liquid level height is obtained, including:

为第二真实回波信号，S(k)为第一回波信号，

为第一虚假回波信号，T为扫频时宽，B为扫频带宽，c为电磁波在真空中传播速度，f_s为接收采样频率，M为频谱采样总点数。where y _k is the initial measured liquid level value of the predicted liquid level,

is the second real echo signal, S(k) is the first echo signal,

is the first false echo signal, T is the frequency sweep time width, B is the frequency sweep bandwidth, c is the propagation speed of electromagnetic waves in vacuum, f _s is the receiving sampling frequency, and M is the total number of spectrum sampling points.

According to the embodiments of the present disclosure, performing Kalman filtering processing on the initial measured liquid level value to obtain the measured liquid level value of the predicted liquid level height may include:

Kalman filtering is performed on the initial measured liquid level value to obtain the measured liquid level value of the predicted liquid level height in the target container and the liquid level change speed value in the target container; the measured liquid level value is output as the final output result.

According to an embodiment of the present disclosure, Kalman filtering is performed on the initial measured liquid level value to obtain the measured liquid level value of the predicted liquid level height in the target container and the liquid level change speed value in the target container, including:

Among them, x is the measured liquid level value, v is the liquid level change speed value of two adjacent measurements, T is the time interval between two adjacent measurements, and the process noise ω _m is a white noise vector with a two-dimensional mean value of zero. The noise _{vm is a white noise signal with zero mean value, and y m is} the measured liquid level value processed by Kalman filtering.

FIG. 5 schematically shows a schematic diagram of the relationship between the measured value and the real value of the data processing method according to an embodiment of the present disclosure.

FIG. 6 schematically shows a schematic diagram of the error between the measured value and the actual value of the data processing method according to an embodiment of the present disclosure.

According to the embodiment of the present disclosure, as shown in FIG. 5 and FIG. 6 , the segmented coaxial guided wave radar level gauge has four sections of probes. The first section of the probe is connected to the feed port through a flange, and the length of For example, the length of the remaining three sections of the probe is 1.2m, and the total number of spectrum sampling points is 131072. In the whole measurement range, the error between the liquid level measurement value and the actual value can be kept within ±1cm. It can be seen that the data processing method according to the embodiment of the present disclosure can effectively process the liquid level of the segmented coaxial guided wave radar. Bit count data.

FIG. 7 schematically illustrates a block diagram of a data processing system 700 according to an embodiment of the present disclosure.

As shown in FIG. 7 , the data processing system 700 provided by the embodiment of the present disclosure may include a prediction module 701 , a first calculation module 702 , a first acquisition module 703 , a second calculation module 704 , and a processing module 705 .

The prediction module 701 is configured to predict the predicted value of the liquid level in the target container in the next measurement according to the measured liquid level value and the liquid level change speed value of the current liquid level height in the target container.

The first calculation module 702 is configured to calculate the first false echo signal in the next measured first echo signal according to the predicted value and the length of each section of the probe.

The first acquisition module 703 is configured to acquire the first echo signal of the probe when the liquid in the target container is at the predicted liquid level height.

The second calculation module 704 calculates the initial measured liquid level value of the predicted liquid level according to the first echo signal and the first false echo signal.

The processing module 705 is configured to perform Kalman filtering processing on the initial measured liquid level value to obtain the measured liquid level value of the predicted liquid level height.

According to the embodiment of the present disclosure, the false echo signal in the echo signal of the next measurement can be calculated by the predicted value of the liquid level height in the target container and the length of each section of the probe in the next measurement, and then according to the false echo signal. The echo signal calculates the real echo signal of each measurement, which can eliminate the influence of the false echo caused by the discontinuous impedance at the feed port and the connection of each probe on the measurement result, and effectively improve the measurement accuracy. At the same time, the present disclosure can reduce the influence of external interference or instantaneous liquid level jitter on the measurement by performing Kalman filtering processing on the liquid level value, and further improve the measurement accuracy.

According to an embodiment of the present disclosure, the data processing system 700 may further include a second acquisition module and a third calculation module.

The second acquisition module is used to acquire the background echo signal of the probe when there is no liquid in the target container and the initial echo signal of the probe when the liquid in the target container is at the initial liquid level height, respectively.

The third calculation module calculates the measured liquid level value and the liquid level change speed value of the initial liquid level height according to the background echo signal and the initial echo signal.

According to an embodiment of the present disclosure, the second acquisition module may include a first acquisition unit and a first transformation unit.

The first acquisition unit is used to separately acquire the second echo signal of the probe when there is no liquid in the target container and the third echo signal of the probe when the liquid in the target container is at the initial liquid level height.

The first transformation unit is configured to perform linear frequency modulation Z transformation on the second echo signal and the third echo signal respectively to obtain the background echo signal and the initial echo signal.

According to an embodiment of the present disclosure, the third calculation module may include a first calculation unit, a first elimination unit, a first positioning unit, and a second calculation unit.

The first calculation unit is configured to obtain the second false echo signal at the feeding port of the probe according to the background echo signal.

The first elimination unit is configured to eliminate the false echo signal in the initial echo signal according to the second false echo signal to obtain the first real echo signal.

The first positioning unit is used for processing the first real echo signal by the method of wave peak positioning to obtain the initial liquid level height value.

The second calculation unit is configured to calculate the value of the liquid level change speed according to the initial liquid level height value.

According to an embodiment of the present disclosure, the first acquisition module 703 may include a second acquisition unit and a second transformation unit.

The second acquisition unit is used for acquiring the fourth echo signal of the probe when the liquid in the target container is at the predicted liquid level.

The second transformation unit is configured to perform chirp-Z transformation on the fourth echo signal within a window centered on the predicted value to obtain the first echo signal.

According to an embodiment of the present disclosure, the second calculation module 704 may include a second elimination unit and a second positioning unit.

The second elimination unit is configured to eliminate the false echo signal in the first echo signal according to the first false echo signal to obtain the second real echo signal.

The second positioning unit is used for processing the second real echo signal by the method of wave peak positioning to obtain the initial measured liquid level value of the predicted liquid level height.

According to an embodiment of the present disclosure, the processing module 705 may include a processing unit and an output unit.

The processing unit is configured to perform Kalman filter processing on the initial measured liquid level value to obtain the measured liquid level value of the predicted liquid level height in the target container and the liquid level change speed value in the target container.

The output unit is used to output the measured liquid level value as the final output result.

Any of the modules, sub-modules, units, sub-units, or at least part of the functions of any of them according to embodiments of the present disclosure may be implemented in one module. Any one or more of the modules, sub-modules, units, and sub-units according to the embodiments of the present disclosure may be divided into multiple modules for implementation. Any one or more of the modules, sub-modules, units, sub-units according to embodiments of the present disclosure may be implemented at least in part as hardware circuits, such as field programmable gate arrays (FPGA), programmable logic arrays (PLA), A system on a chip, a system on a substrate, a system on a package, an application specific integrated circuit (ASIC), or any other reasonable means of hardware or firmware that integrates or packages circuits, or can be implemented in software, hardware, and firmware Any one of these implementations or an appropriate combination of any of them is implemented. Alternatively, one or more of the modules, sub-modules, units, and sub-units according to embodiments of the present disclosure may be implemented at least in part as computer program modules that, when executed, may perform corresponding functions.

For example, any number of the prediction module 701, the first calculation module 702, the first acquisition module 703, the second calculation module 704, and the processing module 705 may be combined in one module/unit/subunit to implement, or any one of them A module/unit/subunit can be split into multiple modules/units/subunits. Alternatively, at least part of the functionality of one or more of these modules/units/subunits may be combined with at least part of the functionality of other modules/units/subunits and combined in one module/unit/subunit realized in. According to an embodiment of the present disclosure, at least one of the prediction module 701 , the first calculation module 702 , the first acquisition module 703 , the second calculation module 704 , and the processing module 705 may be at least partially implemented as a hardware circuit, eg, field programmable Gate Array (FPGA), Programmable Logic Array (PLA), System on Chip, System on Substrate, System on Package, Application Specific Integrated Circuit (ASIC), or any other reasonable means by which circuits can be integrated or packaged, etc. It can be implemented in hardware or firmware, or in any one of the three implementation manners of software, hardware and firmware, or in an appropriate combination of any of them. Alternatively, at least one of the prediction module 701 , the first calculation module 702 , the first acquisition module 703 , the second calculation module 704 and the processing module 705 may be implemented at least in part as a computer program module, when the computer program module is executed , can perform the corresponding function.

It should be noted that the part of the data processing system 700 in the embodiment of the present disclosure corresponds to the part of the data processing method in the embodiment of the present disclosure, and the description of the part of the data processing system 700 specifically refers to the part of the data processing method, which is not repeated here. Repeat.

Figure 8 schematically illustrates a block diagram of a computer system suitable for implementing the methods described above, according to an embodiment of the present disclosure. The computer system shown in FIG. 8 is only an example, and should not impose any limitation on the function and scope of use of the embodiments of the present disclosure.

As shown in FIG. 8 , a computer system 800 according to an embodiment of the present disclosure includes a processor 801 that can be loaded into a random access memory (RAM) 803 according to a program stored in a read only memory (ROM) 802 or from a storage portion 808 program to perform various appropriate actions and processes. The processor 801 may include, for example, a general-purpose microprocessor (eg, a CPU), an instruction set processor and/or a related chipset, and/or a special-purpose microprocessor (eg, an application-specific integrated circuit (ASIC)), among others. The processor 801 may also include onboard memory for caching purposes. The processor 801 may include a single processing unit or multiple processing units for performing different actions of the method flow according to the embodiments of the present disclosure.

In the RAM 803, various programs and data necessary for the operation of the system 800 are stored. The processor 801 , the ROM 802 , and the RAM 803 are connected to each other through a bus 804 . The processor 801 performs various operations of the method flow according to the embodiment of the present disclosure by executing the programs in the ROM 802 and/or the RAM 803 . Note that the program may also be stored in one or more memories other than the ROM 802 and the RAM 803 . The processor 801 may also perform various operations of the method flow according to the embodiments of the present disclosure by executing programs stored in the one or more memories.

According to an embodiment of the present disclosure, the system 800 may also include an input/output (I/O) interface 805 that is also connected to the bus 804 . System 800 may also include one or more of the following components connected to I/O interface 805: input portion 806 including keyboard, mouse, etc.; including components such as cathode ray tube (CRT), liquid crystal display (LCD), etc., and speakers An output section 807 including a hard disk, etc.; a storage section 808 including a hard disk, etc.; and a communication section 809 including a network interface card such as a LAN card, a modem, and the like. The communication section 809 performs communication processing via a network such as the Internet. A drive 810 is also connected to the I/O interface 805 as needed. A removable medium 811, such as a magnetic disk, an optical disk, a magneto-optical disk, a semiconductor memory, etc., is mounted on the drive 810 as needed so that a computer program read therefrom is installed into the storage section 808 as needed.

According to an embodiment of the present disclosure, the method flow according to an embodiment of the present disclosure may be implemented as a computer software program. For example, embodiments of the present disclosure include a computer program product comprising a computer program carried on a computer-readable storage medium, the computer program containing program code for performing the method illustrated in the flowchart. In such an embodiment, the computer program may be downloaded and installed from the network via the communication portion 809, and/or installed from the removable medium 811. When the computer program is executed by the processor 801, the above-described functions defined in the system of the embodiment of the present disclosure are performed. According to embodiments of the present disclosure, the above-described systems, apparatuses, apparatuses, modules, units, etc. can be implemented by computer program modules.

The present disclosure also provides a computer-readable storage medium. The computer-readable storage medium may be included in the device/apparatus/system described in the above embodiments; it may also exist alone without being assembled into the device/system. device/system. The above-mentioned computer-readable storage medium carries one or more programs, and when the above-mentioned one or more programs are executed, implement the method according to the embodiment of the present disclosure.

According to an embodiment of the present disclosure, the computer-readable storage medium may be a non-volatile computer-readable storage medium. Examples may include, but are not limited to, portable computer disks, hard disks, random access memory (RAM), read only memory (ROM), erasable programmable read only memory (EPROM or flash memory), portable compact disk read only memory (CD- ROM), optical storage devices, magnetic storage devices, or any suitable combination of the above. In this disclosure, a computer-readable storage medium may be any tangible medium that contains or stores a program that can be used by or in conjunction with an instruction execution system, apparatus, or device.

For example, according to embodiments of the present disclosure, a computer-readable storage medium may include one or more memories other than ROM 802 and/or RAM 803 and/or ROM 802 and RAM 803 described above.

The embodiments of the present disclosure also include a computer program product, which includes a computer program, the computer program includes program codes for executing the methods provided by the embodiments of the present disclosure, and when the computer program product runs on an electronic device, the program The code is used to enable the electronic device to implement the data processing method provided by the embodiments of the present disclosure.

When the computer program is executed by the processor 801, the above-mentioned functions defined in the system/device of the embodiment of the present disclosure are performed. According to embodiments of the present disclosure, the systems, apparatuses, modules, units, etc. described above may be implemented by computer program modules.

In one embodiment, the computer program may rely on a tangible storage medium such as an optical storage device, a magnetic storage device, or the like. In another embodiment, the computer program may also be transmitted, distributed in the form of a signal over a network medium, downloaded and installed through the communication section 809, and/or installed from a removable medium 811. The program code embodied by the computer program may be transmitted using any suitable network medium, including but not limited to: wireless, wired, etc., or any suitable combination of the foregoing.

According to the embodiments of the present disclosure, the program code for executing the computer program provided by the embodiments of the present disclosure may be written in any combination of one or more programming languages, and specifically, high-level procedures and/or object-oriented programming may be used. programming language, and/or assembly/machine language to implement these computational programs. Programming languages include, but are not limited to, languages such as Java, C++, python, "C" or similar programming languages. The program code may execute entirely on the user computing device, partly on the user device, partly on a remote computing device, or entirely on the remote computing device or server. In the case of a remote computing device, the remote computing device may be connected to the user computing device through any kind of network, including a local area network (LAN) or a wide area network (WAN), or may be connected to an external computing device (eg, using an Internet service provider business via an Internet connection).

The flowchart and block diagrams in the Figures illustrate the architecture, functionality, and operation of possible implementations of systems, methods and computer program products according to various embodiments of the present disclosure. In this regard, each block in the flowchart or block diagrams may represent a module, segment, or portion of code that contains one or more logical functions for implementing the specified functions executable instructions. It should also be noted that, in some alternative implementations, the functions noted in the blocks may occur out of the order noted in the figures. For example, two blocks shown in succession may, in fact, be executed substantially concurrently, or the blocks may sometimes be executed in the reverse order, depending upon the functionality involved. It is also noted that each block of the block diagrams or flowchart illustrations, and combinations of blocks in the block diagrams or flowchart illustrations, can be implemented in special purpose hardware-based systems that perform the specified functions or operations, or can be implemented using A combination of dedicated hardware and computer instructions is implemented. Those skilled in the art will appreciate that various combinations and/or combinations of features recited in various embodiments and/or claims of the present disclosure are possible, even if such combinations or combinations are not expressly recited in the present disclosure. In particular, various combinations and/or combinations of the features recited in the various embodiments of the present disclosure and/or in the claims may be made without departing from the spirit and teachings of the present disclosure. All such combinations and/or combinations fall within the scope of this disclosure.

Embodiments of the present disclosure have been described above. However, these examples are for illustrative purposes only, and are not intended to limit the scope of the present disclosure. Although the various embodiments are described above separately, this does not mean that the measures in the various embodiments cannot be used in combination to advantage. The scope of the present disclosure is defined by the appended claims and their equivalents. Without departing from the scope of the present disclosure, those skilled in the art can make various substitutions and modifications, and these substitutions and modifications should all fall within the scope of the present disclosure.

Claims (10)

1. A data processing method of a segmented guided wave radar liquid level meter comprises the following steps:

predicting a predicted value of the liquid level height in the target container at the next measurement according to the measured liquid level value and the liquid level change speed value of the current liquid level height in the target container;

calculating a first false echo signal in the first echo signal measured next time according to the predicted value and the length of each segment of the waveguide rod;

acquiring a first echo signal of the wave guide rod when the liquid in the target container is positioned at the predicted liquid level height;

calculating an initial measured level value for the predicted level height from the first echo signal and the first spurious echo signal;

and performing Kalman filtering processing on the initial measurement liquid level value to obtain the measurement liquid level value of the predicted liquid level height.

2. The method of claim 1, further comprising:

respectively acquiring a background echo signal of the wave guide rod when no liquid exists in the target container and an initial echo signal of the wave guide rod when the liquid in the target container is positioned at an initial liquid level height;

and calculating a measurement liquid level value and a liquid level change speed value of the initial liquid level height according to the background echo signal and the initial echo signal.

3. The method of claim 2, wherein the separately obtaining the background echo signal of the waveguide rod when no liquid is in the target vessel and the initial echo signal of the waveguide rod when the liquid in the target vessel is at an initial liquid level comprises:

respectively collecting a second echo signal of the wave guide rod when no liquid exists in the target container and a third echo signal of the wave guide rod when the liquid in the target container is positioned at the initial liquid level height;

and respectively carrying out linear frequency modulation Z conversion on the second echo signal and the third echo signal to obtain the background echo signal and the initial echo signal.

4. The method of claim 2, wherein the background echo signal comprises:

c(t)＝c₀(t)+c₁(t)+c₂(t)+…+c_Q(t)

wherein c (t) is background echo signal, c₀(t) reflected signals due to impedance mismatch at the feed port of the waveguide rod, c₁(t) is a length L from the feed port of the waveguide rod₁C a reflection signal generated at the junction of the first and second guided wave rods, c₂(t) is a length L from the feed port of the waveguide rod₂C reflected signal generated at the joint of the second and third guided wave rods, c_Q(t) is a length L from the feed port of the waveguide rod_QThe total reflection signal caused by the short circuit of the tail end of the waveguide rod in the Q section.

5. The method of claim 4, wherein said calculating a measured level value and a level change velocity value for said initial liquid level height from said background echo signal and said initial echo signal comprises:

obtaining a second false echo signal at the feed port of the waveguide rod according to the background echo signal;

eliminating the false echo signal in the initial echo signal according to the second false echo signal to obtain a first real echo signal;

processing the first real echo signal by a peak positioning method to obtain an initial liquid level height value;

and calculating the liquid level change speed value according to the initial liquid level height value.

6. The method of claim 1, wherein predicting a predicted value of the liquid level in the target container at the next measurement based on the measured liquid level value of the current liquid level in the target container comprises:

wherein,

in order to measure the level value of the liquid,

the liquid level change speed values of two adjacent measurements are obtained, and T is the time interval of the two adjacent measurements.

7. The method of claim 1, wherein said calculating a first false echo signal in said next measured first echo signal based on said predicted values and waveguide rod segment lengths comprises:

wherein,

is the first false echo signal, C_i(k) Is L from the feed port of the waveguide rod_iJ is the number of segments of the waveguide rod between the predicted value and the feed port, L_J≤X＜L_J+1And X is a predicted value.

8. The method of claim 1, wherein the obtaining a first echo signal of the waveguide rod when the liquid in the target vessel is at the predicted liquid level comprises:

collecting a fourth echo signal of the wave guide rod when the liquid in the target container is positioned at the predicted liquid level height;

and performing linear frequency modulation Z conversion on the fourth echo signal in a window taking the predicted value as the center to obtain the first echo signal.

9. The method of claim 1, wherein said calculating an initial measured level value of said predicted level from said first echo signal and said first spurious echo signal comprises:

eliminating the false echo signal in the first echo signal according to the first false echo signal to obtain a second real echo signal;

and processing the second real echo signal by a peak positioning method to obtain an initial measurement liquid level value of the predicted liquid level height.

10. The method of claim 1, wherein the kalman filtering the initial measured level value to obtain the measured level value of the predicted liquid level height comprises:

performing Kalman filtering processing on the initial measurement level value to obtain a measurement level value of the predicted liquid level height in the target container and the liquid level change speed value in the target container;

and outputting the measured liquid level value as a final output result.

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