Method and apparatus for pre-processing of mos gas sensor array signals

Abstract

This invention relates to the field of MOS gas sensor array technology. To address the problem of varying MOS gas sensor array signals within a uniform scale range while eliminating the influence of interference factors, this invention provides a preprocessing method for MOS gas sensor array signals. The method includes: driving a target gas into a gas chamber to replace the air inside; and during the process of driving the target gas into the gas chamber, acquiring a first electrical signal output by the MOS gas sensor according to a preset acquisition frequency; filtering the first electrical signal to obtain a second electrical signal; and performing scale transformation processing on the second electrical signal to obtain a third electrical signal. The filtering process of this invention can eliminate abnormal fluctuations in the electrical signal, thereby improving the stability of the electrical signal acquired by the MOS gas sensor. The scale transformation processing enables the signal to vary within a uniform scale range while eliminating the influence of interference factors, thereby effectively improving the consistency and stability of the signal.

Description

Technical Field

[0001] This invention relates to the field of MOS gas sensor array technology, and specifically provides a preprocessing method and apparatus for MOS gas sensor array signals. Background Technology

[0002] MOS gas sensors, or metal oxide semiconductor gas sensors, primarily use metal oxide semiconductors as their sensing material. The main principle of a MOS gas sensor is that its resistance in air is R0. Under certain conditions, the higher the concentration of the target gas in contact with it, the higher the resistance R0 of the MOS gas sensor. S The lower the value, the better. S / R0 matches the sensitivity characteristic curve. Connect the MOS gas sensor to a load resistor R. L They are connected in series, and a DC loop voltage V is applied across the two ends of this series circuit. C The voltage V across the load resistor RL The collected value is the signal value of the MOS gas sensor, such as... Figure 1 As shown.

[0003] A MOS gas sensor array, composed of multiple MOS gas sensors, generates multiple signals through contact with the target gas. Combined with algorithms such as pattern recognition and deep learning, it can be used for gas type or odor identification, such as the identification of hazardous chemicals, pollutants, disease markers, types of liquor, and the degree of food spoilage. Gas type or odor identification algorithms typically require high consistency and stability of the input signal, meaning it should vary within the same scale range and be as minimally affected by interference factors as possible.

[0004] However, different models of MOS gas sensors exhibit inconsistent signal value variation ranges, showing significant differences, typically manifested as large variations in initial signal values ​​and amplitudes. Furthermore, even the same model of MOS gas sensor can be affected by various interference factors, resulting in variations in signal value consistency and stability between different individuals and under different conditions. This typically manifests as differences in initial and maximum signal values, as well as abnormal signal fluctuations. These interference factors include at least the following:

[0005] 1. Manufacturing batch: Due to the manufacturing process, there are individual differences in the same model of sensor, resulting in inconsistent signals from MOS gas sensors;

[0006] 2. Circuit conditions: Different or fluctuating loop voltages applied across the aforementioned series circuit, or different resistance values ​​between the MOS gas sensor and the load resistor, can cause inconsistent or unstable signals from the MOS gas sensor.

[0007] 3. Acquisition System: The voltage signal ADC (Analog-to-Digital Converter) bits of the acquisition system are different, and the same acquired voltage will be converted into different digital values, resulting in inconsistent signals from the MOS gas sensor;

[0008] 4. Environment: Variations or fluctuations in temperature, humidity, and background gas concentration in the environment can cause inconsistent or unstable signals from the MOS gas sensor.

[0009] 5. Usage: Different preheating times or continuous use result in different recovery levels of the sensor, leading to inconsistent and unstable signals from the MOS gas sensor.

[0010] The application of MOS gas sensors in gas detection alarms differs from their application in gas type or odor identification. Gas detection alarms typically measure the concentration of a single gas (such as methane) and trigger an alarm based on a preset value. Before leaving the factory, the MOS gas sensor signal is calibrated by passing a standard gas of known type and concentration through it. This calibration includes zero-point calibration, alarm value calibration, range calibration, and curve fitting calibration, and the calibration data is stored in the gas detection alarm's measurement program. After calibration, the gas detection alarm can measure the gas concentration during actual use and can, to some extent, eliminate the influence of interference factors 1, 2, and 3 mentioned above, but generally cannot eliminate the influence of interference factors 4 and 5.

[0011] In gas type or odor recognition applications, after acquiring the sampling signal from the MOS gas sensor array, preprocessing is required. The main purpose of preprocessing is to eliminate various interference factors, obtain the true response of the MOS gas sensor, and make the MOS gas sensor array signal more consistent and stable, thereby reducing the difficulty of subsequent recognition and improving the performance of the recognition algorithm. Common preprocessing methods include baseline processing and normalization. Baseline processing eliminates zero-point differences in the signal. Normalization ensures that the signal values ​​vary within the same scale range.

[0012] However, in gas type or odor recognition applications, the target gas is variable and unknown, and may even be a mixture with incompletely defined composition (such as human exhaled breath). Furthermore, the maximum concentration of the target gas cannot be given a specific range. Therefore, it is impossible to eliminate interference factors 1, 2, and 3 using standard gas calibration methods, nor is it possible to eliminate the influence of interference factors 1 to 5 while varying the MOS gas sensor array signal within the same scale range through baseline processing and normalization. Currently, there is no preprocessing method or device for MOS gas sensor array signals that can eliminate the influence of interference factors 1 to 5 while varying the MOS gas sensor array signal within the same scale range.

[0013] Therefore, there is an urgent need in the field for a preprocessing method and apparatus for MOS gas sensor array signals to solve the above problems. Summary of the Invention

[0014] The present invention aims to solve the above-mentioned technical problems, namely, to solve the problem of making the signal of the MOS gas sensor array vary within the same scale range while eliminating the influence of interference factors on the MOS gas sensor.

[0015] In a first aspect, the present invention provides a preprocessing method for signals from a MOS gas sensor array, the MOS gas sensor array comprising a plurality of MOS gas sensors disposed in a gas chamber, the preprocessing method comprising the following steps:

[0016] Air is forced into the gas chamber to replace the original gas in the gas chamber. When the electrical signal output by the MOS gas sensor reaches a stable state, the first output value output by the MOS gas sensor is obtained.

[0017] The target gas is driven into the gas chamber to replace the air in the gas chamber. During the process of driving the target gas into the gas chamber, the first electrical signal output by the MOS gas sensor is acquired according to a preset acquisition frequency, and the first output value is used as the first acquisition signal value of the first electrical signal.

[0018] The first electrical signal is filtered to obtain the second electrical signal;

[0019] The second electrical signal is scaled to obtain the third electrical signal.

[0020] In a specific implementation of the above preprocessing method, "filtering the first electrical signal to obtain the second electrical signal" includes:

[0021] A F [0][i]=A L [0][i];

[0022] A F [t max [i] = A L [t max [i];

[0023] Where t is the time number at which the first electrical signal is acquired, and the value of t ranges from 0 to t. mmax t=0 represents the first data collection, t=t mmax Representing the last data collection, A L For the first electrical signal, A F The second electrical signal is denoted by , and i is the number of the MOS gas sensor.

[0024] In the specific implementation of the above preprocessing method, "filtering the first electrical signal to obtain a second electrical signal" further includes:

[0025] Judging whether A mmax at t not equal to 0 or t L [t][i] meets the preset conditions. If it meets the preset conditions, filtering is performed; if it does not meet the preset conditions, then A F [t][i] = A L [t][i].

[0026] In the specific implementation of the above preprocessing method, "judging whether A max at t not equal to 0 or t L [t][i] meets the preset conditions. If it meets the preset conditions, filtering is performed" includes:

[0027] If A L [t][i] < A F [0][i], then A F [t][i] = A F [0][i].

[0028] In the specific implementation of the above preprocessing method, "judging whether A max at t not equal to 0 or t L [t][i] meets the preset conditions. If it meets the preset conditions, filtering is performed" further includes:

[0029] If A L [t][i] > A F [t - 1][i] and A L [t][i] ≥ A L [t + 1][i], or A L [t][i] < A F [t - 1][i] and A L [t][i] = A L [t + 1][i], then A F [t][i] = A F [t - 1][i];

[0030] where t + 1 represents the next acquisition after the t-th acquisition, and t - 1 represents the previous acquisition before the t-th acquisition.

[0031] In the specific implementation of the above preprocessing method, "judging whether A max at t not equal to 0 or t L [t][i] meets the preset conditions. If it meets the preset conditions, filtering is performed" further includes:

[0032] If A L [t][i]<A F [t-1][i]andA L [t][i]<A L [t+1][i], then A F [t][i]=min{A F [t-1][i], A L [t+1][i]};

[0033] Where min{} represents taking the minimum value between the two elements inside {}.

[0034] In a specific implementation of the above preprocessing method, "determine whether t is not equal to 0 or t..." max A at that time L "[t][i] Whether it meets the preset conditions, if it meets the preset conditions, perform filtering processing" also includes:

[0035] If A L [t][i]≥A max [t], then A F [t][i]=A max [t]-1;

[0036] Among them, A max [t] is for obtaining A L The loop voltage acquisition value of the MOS gas sensor array obtained at time [t][i].

[0037] In a specific implementation of the above preprocessing method, "performing a scaling transformation on the second electrical signal to obtain a third electrical signal" includes:

[0038]

[0039] Among them, A P Representing the third electrical signal, A max [0] To obtain A L The loop voltage acquisition value of the MOS gas sensor array obtained at [0][i].

[0040] Secondly, the present invention provides a preprocessing apparatus for signals from a MOS gas sensor array, comprising:

[0041] air chamber;

[0042] A MOS gas sensor array is disposed in the gas chamber;

[0043] The control module is configured to perform the preprocessing method described above.

[0044] By employing the above technical solution, this invention performs filtering and scaling processing on the first electrical signal acquired by the MOS gas sensor. Filtering eliminates abnormal fluctuations in the electrical signal, thereby improving the stability of the electrical signal acquired by the MOS gas sensor. Scaling processing enables the MOS gas sensor array signal to vary within the same scale range, while eliminating the influence of interference factors, thus effectively improving the consistency and stability of the signal acquired by the MOS gas sensor. Attached Figure Description

[0045] The preferred embodiments of the present invention are described below with reference to the accompanying drawings, in which:

[0046] Figure 1 This is a circuit diagram of a MOS gas sensor array composed of multiple MOS gas sensors and their auxiliary circuits provided by the present invention;

[0047] Figure 2 This is a first electrical signal diagram under the first test condition provided by the present invention;

[0048] Figure 3 This is a second electrical signal diagram under the first test condition provided by the present invention;

[0049] Figure 4 This is the third electrical signal diagram under the first test conditions provided by the present invention;

[0050] Figure 5 This is an electrical signal diagram under the first test condition provided by the present invention, in which the first electrical signal is not filtered and is directly subjected to scale transformation.

[0051] Figure 6 This is an electrical signal diagram under the first test condition provided by the present invention, which undergoes relative differential baseline processing and logarithmic function normalization processing on the first electrical signal;

[0052] Figure 7 This is a first electrical signal diagram under the second test condition provided by the present invention;

[0053] Figure 8 This is a second electrical signal diagram under the second test condition provided by the present invention;

[0054] Figure 9 This is a third electrical signal diagram under the second test condition provided by the present invention;

[0055] Figure 10 This is an electrical signal diagram under the second test condition provided by the present invention, in which the first electrical signal is not filtered and is directly subjected to scale transformation.

[0056] Figure 11This is an electrical signal diagram under the second test condition provided by the present invention, which involves relative differential baseline processing and logarithmic function normalization processing of the first electrical signal.

[0057] Figure 12 This is the first electrical signal diagram under the third test condition provided by the present invention;

[0058] Figure 13 This is the second electrical signal diagram under the third test condition provided by the present invention;

[0059] Figure 14 This is the third electrical signal diagram under the third test condition provided by the present invention;

[0060] Figure 15 This is an electrical signal diagram under the third test condition provided by the present invention, in which the first electrical signal is not filtered and is directly subjected to scale transformation.

[0061] Figure 16 This is an electrical signal diagram under the third test condition provided by the present invention, which involves relative differential baseline processing and logarithmic function normalization processing of the first electrical signal. Detailed Implementation

[0062] Preferred embodiments of the present invention will now be described with reference to the accompanying drawings. Those skilled in the art should understand that these embodiments are merely illustrative of the technical principles of the present invention and are not intended to limit the scope of protection of the present invention.

[0063] It should be noted that in the description of this invention, terms such as "upper," "lower," "left," "right," "inner," and "outer," indicating directional or positional relationships, are based on the directional or positional relationships shown in the accompanying drawings. These are merely for ease of description and do not indicate or imply that the device or element must have a specific orientation, or be constructed and operated in a specific orientation; therefore, they should not be construed as limitations on this invention. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0064] Furthermore, it should be noted that, in the description of this invention, unless otherwise explicitly specified and limited, the terms "installation," "setting," and "connection" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a direct connection, an indirect connection through an intermediate medium, or a connection within two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0065] This addresses the problem of varying the signal of a MOS gas sensor array within the same scale range while eliminating the influence of interference factors on the MOS gas sensor.

[0066] This embodiment discloses a preprocessing device for signals from a MOS gas sensor array, which is mainly used for gas type or odor identification, and can also be used for gas concentration identification, gas detection alarm, etc.

[0067] The pretreatment device includes a gas chamber, a MOS gas sensor array, and a control module.

[0068] The air chamber is equipped with an inlet and an outlet. External gas can enter the air chamber through the inlet, and the gas inside the air chamber can be discharged through the outlet. Preferably, the inlet and outlet are small in size to avoid external airflow disturbances affecting the interior of the air chamber. Furthermore, the outlet is connected to an intake pump, which can drive the existing gas in the air chamber to exit through the outlet, while simultaneously driving external gas into the air chamber through the inlet. If a target gas is connected to the inlet, the intake pump can drive the existing gas in the air chamber to exit, allowing the target gas to enter the air chamber and replace the existing gas.

[0069] Reference Figure 1 A MOS gas sensor array comprises multiple MOS gas sensors and their associated circuitry, housed within a gas chamber. When a MOS gas sensor comes into contact with the gas within the chamber, it generates an electrical signal. Each MOS gas sensor also includes associated circuitry, such as… Figure 1 As shown, the MOS gas sensor R S With load resistance R L Connect them in series, and apply a DC loop voltage V across the two ends of the series circuit. C , for MOS gas sensor R S With load resistance R L Power supply. Load resistance R L Both ends are signal ports, through which the signal voltage V is acquired. RL .

[0070] The control module includes a power supply module, a sampling module, and a multi-channel analog-to-digital converter. The power supply module is connected to the power port of the aforementioned auxiliary circuitry, supplying power to the MOS gas sensor R. S With load resistance R L Power supply. The sampling module is connected to the signal port of the auxiliary circuit to receive voltage V. RL The signal. A multi-channel analog-to-digital converter can process voltage V. RL The signal is sampled to obtain the first electrical signal; the multi-channel analog-to-digital converter can also sample the loop voltage V. C Sampling is performed to obtain the collected value A of the loop voltage. maxIn this embodiment, the main body of the control module is a microcontroller, and the multi-channel analog-to-digital converter is an ADC module mounted on the microcontroller; in other embodiments, the multi-channel analog-to-digital converter can also be replaced by a multi-channel analog-to-digital converter chip or multiple single-channel analog-to-digital converter chips mounted outside the microcontroller.

[0071] The control module is also configured to perform a preprocessing method for the MOS gas sensor array signal, which includes the following steps:

[0072] S1: Start the intake pump to force air into the gas chamber, thereby expelling the existing gas inside. In other words, the existing gas in the gas chamber is purged by introducing air. When the electrical signal output by the MOS gas sensor reaches a stable state, the intake pump is turned off, and the electrical signal value output by the MOS gas sensor, i.e., the first output value, is obtained through a multi-channel analog-to-digital converter. Specifically, when the variance of the electrical signal output by the MOS gas sensor decreases to a preset threshold, it indicates that "the electrical signal output by the MOS gas sensor has reached a stable state." Further, when the electrical signal output by the MOS gas sensor reaches a stable state, the loop voltage acquisition value A of the MOS gas sensor array is also obtained. max [0].

[0073] S2: Restart the suction pump to drive the target gas into the air chamber and replace the air inside the air chamber.

[0074] S3: During the process of driving the target gas into the gas chamber, according to the preset acquisition frequency, the multi-channel analog-to-digital converter is driven to acquire the electrical signal value output by the MOS gas sensor, which is the first electrical signal, denoted as A. L [t][i],A L The first electrical signal is represented by t, which represents the time number of the acquired signal. The value of t ranges from 0 to t. max t=0 represents the first data collection, t=t max This represents the last acquisition, and 'i' represents the number of the MOS gas sensor in the MOS gas sensor array. The first output value is then used as the first acquisition signal value of the first electrical signal, denoted as A. L [0][i]. Further, when "the multi-channel analog-to-digital converter is driven to acquire the electrical signal value output by the MOS gas sensor according to the preset acquisition frequency", the loop voltage acquisition value A of the MOS gas sensor array at the corresponding time is acquired. max [t].

[0075] S4: Filter the first electrical signal to obtain the second electrical signal. Specifically, this includes the following steps:

[0076] S41: A F [0][i]=A L [0][i],AF [t max [i] = A L [t max ][i], where A F This represents the second electrical signal after filtering.

[0077] S42: Determine if t is not equal to 0 or t max A at that time L [t][i] Whether it meets the preset conditions. If it meets the preset conditions, then perform filtering. If it does not meet the preset conditions, then A... F [t][i]=A L [t][i]. Specifically, "if the preset conditions are met, then perform filtering" includes the following steps:

[0078] S421: If A L [t][i]<A F [0][i], then A F [t][i]=A F [0][i].

[0079] S422: If A L [t][i]>A F [t-1][i]andA L [t][i]≥A L [t+1][i], or A L [t][i]<A F [t-1][i]andA L [t][i]=A L [t+1][i], then A F [t][i]=A F [t-1][i]. Where t+1 represents the next collection after the t-th collection, and t-1 represents the previous collection after the t-th collection.

[0080] S423: If A L [t][i]<A F [t-1][i]andA L [t][i]<A L [t+1][i], then A F [t][i]=min{A F [t-1][i], A L [t+1][i]}. Here, min{} represents taking the minimum value between the two elements within {}.

[0081] S424: If A L [t][i]≥A max [t], then A F [t][i]=Amax [t]-1.

[0082] The above steps complete "S4: Filtering the first electrical signal" to obtain the second electrical signal A. F [t][i].

[0083] S5: Perform scaling transformation on the second electrical signal to obtain the third electrical signal. Specifically, Among them, A P This represents the third electrical signal.

[0084] In step S4, filtering the first electrical signal eliminates abnormal fluctuations. In step S5, scaling the second electrical signal adjusts it to the same scale range, while also eliminating interference from the MOS gas sensor.

[0085] Specifically, refer to Figures 2 to 16 ,in Figure 2 This is the first electrical signal diagram under the first test condition. Figure 3 To Figure 2 The image shows the second electrical signal after filtering the first electrical signal. Figure 4 To Figure 3 The image shows the third electrical signal after the second electrical signal in the image has undergone scale transformation. Figure 5 To Figure 2 The first electrical signal in the image is not filtered; the image is directly processed by scaling. Figure 6 To Figure 2 The electrical signal diagram after the first electrical signal in the image has undergone relative differential baseline processing and logarithmic function normalization. Figure 7 The first electrical signal diagram under the second test condition is shown. Figure 8 To Figure 7 The image shows the second electrical signal after filtering the first electrical signal. Figure 9 To Figure 8 The image shows the third electrical signal after the second electrical signal in the image has undergone scale transformation. Figure 10 To Figure 7 The first electrical signal in the image is not filtered; the image is directly processed by scaling. Figure 11 To Figure 7 The electrical signal diagram after the first electrical signal in the image has undergone relative differential baseline processing and logarithmic function normalization. Figure 12 This is the first electrical signal diagram under the third test condition. Figure 13 To Figure 12 The image shows the second electrical signal after filtering the first electrical signal. Figure 14 To Figure 13 The image shows the third electrical signal after the second electrical signal in the image has undergone scale transformation. Figure 15To Figure 12 The first electrical signal in the image is not filtered; the image is directly processed by scaling. Figure 16 To Figure 12 The electrical signal diagram after the first electrical signal in the image has undergone relative differential baseline processing and logarithmic function normalization.

[0086] The first and second test conditions involve the same gas type and concentration. The difference lies in the introduction of interference factors (i.e., interference factors 1 to 5 in the background art) such as the MOS gas sensor, circuit conditions, acquisition system, environment, and usage method. Specifically, A max and A L [0][i] are different. The difference between the first and third test conditions is the different concentrations of the collected gas.

[0087] Specifically, Figures 2 to 16 The horizontal axis represents the sampling time number t, and the vertical axis represents the electrical signal value.

[0088] contrast Figure 2 and Figure 4 It can be clearly seen that, after preprocessing, the initial values ​​of the third electrical signal from different models of MOS gas sensors become consistent (all are 0) compared to the first electrical signal without preprocessing, and the amplitude of the signals is relatively small. This means that after using the signal preprocessing method provided by the present invention, the signals of the MOS gas sensor array can vary within the same scale range, thereby improving the consistency of the signals acquired by the MOS gas sensor.

[0089] contrast Figure 6 and Figure 11 It is evident that the curves of the two are different, indicating that the existing method of relative differential baseline processing and logarithmic function normalization of the first electrical signal cannot eliminate the influence of interference factors 1 to 5 on the electrical signal, resulting in inconsistent and unstable signal results acquired by the MOS gas sensor. In contrast... Figure 4 and Figure 9 It can be clearly seen that the curves of the two are basically the same, which means that the signal preprocessing method provided by the present invention can effectively eliminate the influence of interference factors 1 to 5, thereby improving the consistency and stability of the signal acquired by the MOS gas sensor.

[0090] Figure 5 The image shows the electrical signal after scaling the first electrical signal without filtering. It is clear that the unfiltered signal exhibits significant fluctuations. Figure 4 The third electrical signal in the image underwent filtering before scaling. As can be clearly seen in the figure, abnormal fluctuations have largely disappeared, and the stability of the acquired electrical signal has been improved. (Comparison) Figure 9 and Figure 10 , Figure 14 and Figure 15 This can also verify the above effects.

[0091] Furthermore, considering the test results under the first, second, and third test conditions, the method of the present invention can improve the consistency and stability of the signals acquired by the MOS gas sensor under different test conditions.

[0092] The technical solution of the present invention has been described above with reference to the preferred embodiments shown in the accompanying drawings. However, it will be readily understood by those skilled in the art that the scope of protection of the present invention is obviously not limited to these specific embodiments. Without departing from the principles of the present invention, those skilled in the art can make equivalent changes or substitutions to the relevant technical features, and the technical solutions after such changes or substitutions will all fall within the scope of protection of the present invention.

Claims

1. A preprocessing method for signals from a MOS gas sensor array, characterized in that, The MOS gas sensor array includes multiple MOS gas sensors, which are disposed in a gas chamber. The pretreatment method includes the following steps: Air is forced into the gas chamber to replace the original gas in the gas chamber. When the electrical signal output by the MOS gas sensor reaches a stable state, the first output value output by the MOS gas sensor is obtained. The target gas is driven into the gas chamber to replace the air in the gas chamber. During the process of driving the target gas into the gas chamber, the first electrical signal output by the MOS gas sensor is acquired according to a preset acquisition frequency, and the first output value is used as the first acquisition signal value of the first electrical signal. The first electrical signal is filtered to obtain the second electrical signal; The second electrical signal is scaled to obtain the third electrical signal; "Performing a scaling transformation on the second electrical signal to obtain a third electrical signal" includes: ; in, Represents the third electrical signal. In order to obtain The loop voltage acquisition value of the MOS gas sensor array obtained at that time. To obtain the time number of the first electrical signal, The value range is from 0 to , This represents the first collection. This represents the last data collection. This is the second electrical signal. This is the serial number of the MOS gas sensor.

2. The pretreatment method according to claim 1, characterized in that, "filtering the first electrical signal to obtain a second electrical signal" comprises: ; ; the first electrical signal.

3. The pre-treatment method according to claim 2, characterized in that, "Filtering the first electrical signal to obtain the second electrical signal" further includes: determining not equal to 0 or when whether a preset condition is met, if the preset condition is met, performing a filtering process, if the preset condition is not met, not performing the filtering process .

4. The pretreatment method according to claim 3, characterized in that, "judging is not equal to 0 or when whether a preset condition is met, and if the preset condition is met, performing a filtering process" includes: If then .

5. The pretreatment method according to claim 4, characterized in that, "judging not equal to 0 or when whether a preset condition is met, and if the preset condition is met, performing a filtering process" further includes: If and or and then wherein, represents the next acquisition of the next acquisition, represents the previous acquisition of the previous acquisition.

6. The pretreatment method according to claim 5, characterized in that, "judging is not equal to 0 or when whether a preset condition is met, and if the preset condition is met, performing a filtering process" further includes: If and then ; wherein represents the minimum of the two elements the minimum of the two elements 7. The pretreatment method according to claim 6, characterized in that, "judging not equal to 0 or when whether a preset condition is met, and if the preset condition is met, performing the filtering process" further includes: If then ; in, In order to obtain The loop voltage acquisition value of the MOS gas sensor array is obtained at that time.

8. A preprocessing device for signals from a MOS gas sensor array, characterized in that, include: air chamber; A MOS gas sensor array is disposed in the gas chamber; A control module configured to perform the preprocessing method as described in any one of claims 1-7.

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