Second-level gas data transmission method, system and device

Abstract

The present application relates to the technical field of gas transmission, and provides a second-level gas data transmission method, system and device, comprising a gas data transmission circuit; wherein the gas transmission circuit comprises a main controller connected with a segmentation circuit; the method comprises: collecting a gas concentration analog signal in a fire smoldering environment in real time through a gas sensing device; wherein the sampling frequency is positively correlated with the gas concentration; performing second-level data segmentation on the gas concentration analog signal through the segmentation circuit through a first clock signal to generate second-level effective data; wherein the first clock signal represents a trigger signal of the initial moment of the periodic growth of the gas concentration, and the second-level effective data is an effective digital quantity signal representing the state of the gas concentration within each second; performing hardware mapping and packaging on the second-level effective data according to a frame structure through the main controller to generate a second-level data frame of the current channel; wherein when the current channel is connected with a host computer, the second-level effective data is transmitted to the host computer.

Description

Technical Field

[0001] This invention relates to the technical field of gas transmission, and in particular to a method, system and apparatus for transmitting gas data at the second level. Background Technology

[0002] In fire early warning systems, traditional sensors for detecting CO gas in smoldering conditions typically have a response time of 60 seconds, insufficient for rapid fire warning. In the very early stages, the concentration of smoldering gases is extremely low. Therefore, we improve the stability and sensitivity of the operational amplifier circuit, combined with software algorithms, to achieve rapid data transmission of smoldering gas concentration data. The transmission method utilizes a 4G network, sending data to the backend at a rate of one data point per second. This ensures rapid real-time data transmission to the backend.

[0003] Traditional gas monitoring circuit boards typically operate on a minute-by-minute basis. In this project, however, minute-by-minute gas data is insufficient for effective fire monitoring and early warning; a much faster response and transmission of all data are required. To address this issue, the sensor's acquisition speed needs to be increased to transmit real-time data to the server for backend analysis. Therefore, a second-level gas data transmission solution is urgently needed. Summary of the Invention

[0004] This application proposes a method, system, and apparatus for second-level gas data transmission. The method uses a segmentation circuit and a multi-stage RC filter circuit to segment the collected gas concentration signal into second-level effective data. The second-level effective data is then hardware-encapsulated to achieve rapid transmission. This method can ensure sampling accuracy, reduce the power consumption of gas sensing devices, and prevent the risk of multi-signal crosstalk and transmission interruption. It is suitable for industrial fire protection.

[0005] To achieve the above objectives, this application provides the following technical solution:

[0006] In a first aspect, this application proposes a second-level gas data transmission method, including a gas data transmission circuit; wherein the gas transmission circuit includes a main controller, and the main controller is connected to a segmentation circuit;

[0007] The method includes:

[0008] The gas concentration simulation signal in the smoldering fire environment is collected in real time by gas sensing equipment; the sampling frequency is positively correlated with the gas concentration.

[0009] The gas concentration analog signal is divided into second-level data by a segmentation circuit using a first clock signal to generate second-level valid data. The first clock signal represents the trigger signal at the initial moment of the periodic increase in gas concentration, and the second-level valid data is an effective digital signal representing the gas concentration state within one second.

[0010] The main controller performs hardware mapping and encapsulation of second-level valid data according to the frame structure to generate second-level data frames for the current channel; when the current channel is connected to the host computer, the second-level valid data is transmitted to the host computer.

[0011] In conjunction with the first aspect, a multi-stage RC filter network is deployed between the segmentation circuit and the gas sensing device. The multi-stage RC filter network includes operational amplifiers, each configured with a preset gain range; wherein,

[0012] The gas concentration simulation signal is filtered to remove electromagnetic noise by a multi-stage RC filter network, and when there is a weak signal at the MV level in the gas concentration simulation signal, the weak signal is amplified through a preset gain range.

[0013] In conjunction with the first aspect, the segmentation circuit includes a capacitor array 321 and an analog switch; wherein,

[0014] When the analog switch is triggered by the rising edge of the first clock signal, a second-level trigger signal is generated, and second-level signal slicing is performed to determine the segmented signal. During the second-level signal slicing process, the switching noise is suppressed in real time by the LC network. The second-level signal slicing process completes no less than 500 signal slices per second, and the timestamp accuracy of the second-level trigger signal is less than 10ms.

[0015] The segmented signal is converted into a digital quantity at a sampling rate of 1MSPS using an analog-to-digital converter. The digital quantity is then divided into segments according to a second-level period. The valid values ​​in the digital quantity are extracted and timestamps are embedded to generate second-level valid data.

[0016] In conjunction with the first aspect, the capacitor array 321 is composed of multiple sub-arrays. The input terminal of the capacitor array 321 is connected to the signal conditioning circuit 320 of the gas sensor through gold-plated pins, and its output terminal is connected to the analog switch through a low-impedance ribbon cable.

[0017] Each subarray consists of at least eight high-precision ceramic capacitors connected in parallel, each subarray receives a single gas analog signal, and the output of each subarray is connected in series with a magnetic bead inductor.

[0018] In conjunction with the first aspect, the analog switch includes a CMOS analog switch chip, and the input channels of the CMOS analog switch chip correspond one-to-one with the sub-array;

[0019] The output of the CMOS analog switch chip is connected in series with a π-type filter and is electrically isolated from the input of the analog-to-digital converter through an optocoupler isolation chip.

[0020] A first sampling resistor is connected in parallel to the common terminal of the CMOS analog switch chip. The first sampling resistor is used to acquire the conduction status signal of the input channel.

[0021] In conjunction with the first aspect, the main controller integrates a hardware acceleration module for encapsulation processing; wherein,

[0022] The hardware acceleration module includes a frame structure generator and data alignment circuitry;

[0023] The frame structure generator concatenates the frame type identifier, timestamp, valid data segment, and checksum according to a preset sequence.

[0024] The data alignment circuit directly maps the second-level valid data collected by the sensor to the corresponding fields in the protocol frame, replacing the software encapsulation process with hardware logic.

[0025] In conjunction with the first aspect, the current channel deployment includes spatiotemporal gating logic; wherein,

[0026] The time-space gating logic includes a channel state detection circuit, which monitors the differential voltage signal of the RS485 bus in real time. When it detects a connection response signal sent by the host computer, it automatically generates a clock enable level until the current second-level data frame transmission is completed.

[0027] The duration of the clock enable level is dynamically determined by the bit width and transmission rate of the RS485 bus protocol frame.

[0028] In conjunction with the first aspect, the current channel also deploys security gating logic and state linkage circuitry; wherein,

[0029] The security gating logic is used to generate a frame transmission status signal when the channel state detection circuit detects a differential voltage signal;

[0030] The status linkage circuit receives the frame transmission status signal and the host computer connection response signal from the RS485 bus. When both the frame transmission status signal and the host computer connection response signal are at a valid level, the clock gating enable terminal is locked through the safety gating logic until the frame transmission completion signal is fed back and the lock is released. During this period, the execution of any clock disable command is prohibited.

[0031] Secondly, this application proposes a second-level gas data transmission system, applicable to the aforementioned second-level gas data transmission method, the system comprising:

[0032] Gas signal acquisition module: used to acquire simulated gas concentration signals in a smoldering fire environment in real time through gas sensing devices; wherein, the sampling frequency is positively correlated with the gas concentration;

[0033] Second-level data segmentation module: used to segment the gas concentration analog signal into second-level data through a segmentation circuit and a first clock signal to generate second-level valid data; wherein, the first clock signal represents the trigger signal at the initial moment of the periodic increase of gas concentration, and the second-level valid data is an effective digital signal representing the gas concentration state within one second.

[0034] Data upload module: Used by the main controller to control the hardware mapping and encapsulation of second-level valid data according to the frame structure, and generate second-level data frames for the current channel; when the current channel is connected to the host computer, the second-level valid data is transmitted to the host computer.

[0035] Thirdly, this application proposes a second-level gas data transmission device, applicable to the aforementioned second-level gas data transmission method, the device comprising:

[0036] Gas sensing devices are deployed in the fire monitoring area to collect simulated gas concentration signals;

[0037] A multi-stage RC filter network is electrically connected to the output of the gas sensing device and filters and amplifies the gas concentration analog signal.

[0038] The segmentation circuit is electrically connected to the output of a multi-stage RC filter network and performs second-level data segmentation on the filtered and amplified gas concentration analog signal.

[0039] The main controller is electrically connected to the segmentation circuit and controls the segmentation circuit to perform second-level data segmentation according to the first clock signal, and obtain the second-level valid data after the second-level data segmentation;

[0040] The 4G network communication module is electrically connected to the output of the main controller and wirelessly connected to the host computer.

[0041] The RS485 communication interface is electrically connected to the output of the main controller and the input of the host computer.

[0042] The power supply circuit is electrically connected to the main controller, multi-stage RC filter network, segmentation circuit, 4G network communication module, and RS485 communication interface, respectively.

[0043] The beneficial effects of the above scheme are as follows:

[0044] This application improves the gas data transmission circuit by adding a segmentation circuit and a multi-stage RC filter circuit. The collected gas concentration signal is segmented into second-level data to generate second-level valid data. Then, the second-level valid data is hardware-encapsulated to achieve fast transmission. This not only ensures sampling accuracy but also reduces the power consumption of the gas sensing device and prevents the risk of multi-signal crosstalk and transmission interruption. It is suitable for industrial fire protection.

[0045] Other features and advantages of the invention will be set forth in the following description, and will be apparent in part from the description, or may be learned by practicing the invention. The objects and other advantages of the invention may be realized and obtained by means of the structures particularly pointed out in the written description and the accompanying drawings.

[0046] The technical solution of the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. Attached Figure Description

[0047] The accompanying drawings are provided to further illustrate the invention and form part of the specification. They are used together with the embodiments of the invention to explain the invention and do not constitute a limitation thereof.

[0048] In the attached diagram:

[0049] Figure 1 This is a flowchart of a second-level gas data transmission method according to an embodiment of the present invention;

[0050] Figure 2 This is a circuit topology diagram of a conventional gas data transmission circuit in an embodiment of the present invention;

[0051] Figure 3 This is a circuit principle topology diagram of the improved gas data transmission circuit in an embodiment of the present invention;

[0052] Figure 4 This is a circuit topology diagram of the main controller MCU in an embodiment of the present invention;

[0053] Figure 5 This is a circuit topology diagram of the power supply circuit in an embodiment of the present invention;

[0054] Figure 6 This is a circuit topology diagram of the DC-DC power conversion circuit in an embodiment of the present invention;

[0055] Figure 7 This is a circuit topology diagram of the memory chip in an embodiment of the present invention;

[0056] Figure 8 This is a circuit topology diagram of the RS485 communication interface in an embodiment of the present invention;

[0057] Figure 9 This is a circuit topology diagram of the RJ45 network interface in an embodiment of the present invention;

[0058] Figure 10 This is a circuit topology diagram of the 4G network communication module in an embodiment of the present invention;

[0059] Figure 11 This is a circuit topology diagram of the isolated I / O circuit in an embodiment of the present invention.

[0060] Figure label:

[0061] 100 is the gas data transmission circuit system, 300 is the segmentation circuit, 210 is the dust sensor, 220 is the gas sensor, 310 is the multi-stage RC filter network, 311 is the first amplifier, 312 is the second amplifier, 320 is the signal conditioning circuit, 321 is the capacitor array, 322 is the first CMOS analog switch chip, 323 is the second CMOS analog switch chip, 324 is the first optocoupler isolation chip, 325 is the second optocoupler isolation chip, 400 is the ADC processor, 110 is the main controller MCU, 120 is the power supply circuit, 130 is the DC-DC power conversion circuit, 140 is the storage chip, 150 is the RS485 communication interface, 160 is the RJ45 network interface, 170 is the 4G network communication module, and 180 is the isolation I / O circuit. Detailed Implementation

[0062] The preferred embodiments of the present invention will be described below with reference to the accompanying drawings. It should be understood that the preferred embodiments described herein are for illustration and explanation only and are not intended to limit the present invention.

[0063] In existing intelligent fire monitoring systems, for fire early warning, comprehensive monitoring of the monitored area is achieved through gas detectors, smoke sensors, and integrated detectors fused with multiple sensors installed in public spaces. Smoldering is a major characteristic of fires. Smoldering is a slow combustion without a flame, mainly manifested by the tendency to overlook open flames and spontaneous combustion of accumulated materials under excessively hot weather. For example, paper, sawdust, fiber fabrics, cellulose boards, latex rubber, and certain porous thermosetting plastics are all highly likely to smolder.

[0064] Traditional methods for monitoring smoldering primarily include carbon dioxide detection, VOC (volatile organic compound) detection, CO (carbon monoxide) detection, and atmospheric aerosol detection. Each of these methods utilizes corresponding sensors. However, traditional fire early warning monitoring has a response time of 60 seconds, and since most smoldering occurs without an open flame, it cannot detect the extremely low concentrations of gases present in the smoldering environment. Therefore, fire early warning cannot be provided. Furthermore, the absence of an open flame in smoldering conditions makes detection errors highly likely.

[0065] Before introducing the embodiments of the second-level gas data transmission method in this application, the conventional gas data transmission circuit system 100 will be introduced first.

[0066] like Figure 2 As shown, Figure 2This is a schematic diagram of the circuit topology of a gas data transmission circuit system 100 in the prior art. The gas data transmission circuit system 100 includes a main controller MCU 100, which is the control core of the gas data transmission circuit system 100. The main controller MCU 100 is powered by a power supply circuit 120 and a power conversion circuit DC-DC 130 connected in series. The 3.3V voltage output terminal of the power conversion circuit DC-DC 130 is connected to the main controller MCU 100. In a smoldering fire environment, when the gas sensor 220 and / or the dust sensor 210 collect dust sensing data and gas sensing data: the gas sensing data is transmitted to the main controller MCU 100 through the isolation IO circuit 180; the dust sensing data is transmitted to the main controller MCU 100 through the RS485 communication interface 150. The main controller MCU 100 analyzes the received dust sensing data and gas sensing data to determine whether there is any data anomaly. If there is a data anomaly, it transmits the data to the host computer through the 4G network communication module 170. Alternatively, all data may be transmitted to a host computer for analysis to determine if any data anomalies exist. In the existing gas data transmission circuit system 100, sensor data includes interference signals, normal gas data, normal dust data, and abnormal sensor data; all data is transmitted to the main controller MCU 100, and then to the host computer. Therefore, data transmission is slow during the upload process to the host computer. The host computer is a remote control terminal, which can be an interactive terminal device such as a computer, mobile phone, or tablet.

[0067] To solve the above problems, such as Figure 3 As shown, this application improves upon the existing gas data transmission circuit system 100 by adding a segmentation circuit 300 and a multi-stage RC filter network 310 to segment the analog signal of the sensor data and generate effective data at the second level. The specific implementation process is as follows:

[0068] Example 1:

[0069] Figure 1 This is a flowchart of a second-level gas data transmission method, suitable for... Figure 3 The gas data transmission circuit 100 in the middle, after adding a segmentation circuit 300 and a multi-stage RC filter network 310, is as follows: Figure 1 As shown, the method of this application includes:

[0070] In a smoldering fire environment, based on step S100: the gas concentration simulation signal in the smoldering fire environment is collected in real time by a gas sensing device; wherein, the sampling frequency is positively correlated with the gas concentration;

[0071] In the embodiments of this application, the smoldering fire environment is the initial stage of a fire, which is characterized by the absence of open flames, slow temperature rise, and the release of large amounts of characteristic gases such as CO and VOCs; the types of gas sensors 220 include various types of sensors such as dust sensors 210, CO, and VOC sensors; it also includes a single sensor or a collection of multiple sensors.

[0072] This gas sensing device is used to collect gas concentration data, determine whether smoldering has occurred, and then convert it into a continuous simulated gas concentration signal. For example, during the smoldering stage, the gas concentration increases periodically by 20% per minute from a baseline concentration. Conventional sensing devices only trigger an alarm when an open flame is detected, at which point the gas concentration may be more than twice the baseline concentration, and it can take several hours from the start of smoldering to the open flame alarm. However, by detecting the gas signal during the smoldering stage, it is possible to determine whether smoldering has occurred within ten minutes.

[0073] The sampling frequency is positively correlated with the gas concentration, which allows gas sensing devices to reduce the sampling frequency in the early stage of smoldering fire (low concentration) to save power, and increase the frequency in the middle stage of smoldering fire (high concentration) to capture details of concentration changes and prevent data redundancy.

[0074] Step S200: The gas concentration analog signal is divided into second-level data by the segmentation circuit 300 through the first clock signal to generate second-level valid data; wherein, the first clock signal represents the trigger signal at the initial moment of the periodic increase of gas concentration, and the second-level valid data is an effective digital signal representing the gas concentration state within one second.

[0075] In the embodiments of this application, after generating the gas concentration analog signal, it is mainly transmitted to the main controller MCU 110 through the RS485 communication interface 150 or the isolated I / O circuit 180; an ADC processor 400 is connected between the RS485 communication interface 150 or the isolated I / O circuit 180 and the segmentation circuit 300; therefore, the acquired gas concentration analog signal is filtered and amplified by the multi-stage RC filter network 310 to output a stable signal, and the stable signal is segmented into second-level segments by the segmentation circuit 300. The second-level valid data after segmentation is converted into digital values ​​by the ADC processor 400, and then transmitted to the main controller MCU 110. The isolated I / O circuit 180 is as follows: Figure 11 As shown.

[0076] When the main controller MCU110 is triggered by the first clock signal, it sends a control command to the segmentation circuit 300, controlling the segmentation circuit 300 to segment the data within each second, determining the second-level valid data. The second-level valid data includes parameters representing the gas concentration, such as the maximum value, average value, and concentration change rate within each second. By discretizing the continuous analog signal into second-level data points, invalid data transmission is reduced, lowering channel bandwidth pressure. Furthermore, clock synchronization based on the first clock signal ensures strict correspondence between data and timestamps, facilitating timing analysis by the host computer. The main controller MCU110, as... Figure 4 As shown.

[0077] The first clock signal is generated by the clock chip integrated into the main controller MCU. This clock chip has a built-in temperature compensation circuit, used in smoldering fire environments to output a 1Hz pulse signal per second, triggered by a rising edge, as the reference timestamp for data segmentation, achieving second-level data segmentation. Second-level segmentation does not mean the data is divided into segments per second; rather, only valid data exists within each second's segment. The main controller MCU110 collects multiple sample values ​​within the first clock cycle (one second) and calculates the second-level valid values ​​using a moving average algorithm, thus representing the second-level valid data.

[0078] For example, when the first clock is triggered, it acts as a trigger signal source, controlling the segmentation circuit 300 to perform time slicing on the continuous analog signal. For example, data framing is performed once per second, and valid signal segments are extracted to generate multiple structured data points. These structured data points, after encapsulation, enable second-level data transmission. Data framing and extraction of valid signal segments reduce the amount of data and improve time accuracy. The first clock acts as a trigger signal source within one cycle of gas concentration change. For example, after determining that the smoldering environment gas concentration has been reached, a 50% increase in the corresponding gas concentration is considered one cycle.

[0079] For example, when detecting gas concentration, the concentration is increased periodically from a preset baseline value to a preset rate of increase and percentage increase. This synchronizes data segmentation with the physical cycle of gas concentration changes, enabling accurate detection of key growth stages of gas concentration in smoldering environments, intuitive observation of smoldering pipe diameter, determination of potential fire risk, and subsequent alarm.

[0080] For example, generating second-level valid data involves digitally processing the segmented signal fragments, using methods such as noise reduction, peak extraction, and average value calculation to determine the characteristic parameters of the gas concentration change in the smoldering environment within a period, thus forming structured data represented by timestamps and concentration values.

[0081] Step S300: The main controller performs hardware mapping and encapsulation of second-level valid data according to the frame structure to generate a second-level data frame for the current channel; wherein, when the current channel is connected to the host computer, the second-level valid data is transmitted to the host computer.

[0082] In this application, data frame structures are mapped according to the channel protocol to achieve high-speed encapsulation. The frame structure includes a frame header (device ID), a data segment (second-level valid data), and a check bit (CRC). The connection status is determined by physical layer signals, and a transmission interrupt is triggered only when the connection is valid. The second-level data frames are linked to the channel status to ensure that the host computer receives the latest data within 1 second, meeting the timeliness requirements of fire early warning. In a smoldering fire environment, low-latency and high-reliability transmission of gas data is achieved through precise time segmentation and channel adaptation.

[0083] For example, the current channel is a dedicated channel for data transmission between the sensor detecting the smoldering environment and the host computer. Second-level data frames are generated by segmenting data into second-level segments to determine the data packet format suitable for the dedicated channel. Standardized, valid data is then rapidly encapsulated using an FPGA frame generator, incorporating a frame header, timestamp, valid data points, and checksum.

[0084] For example, during alarm and data transmission, the connection status of the host computer is determined in real time through the channel status detection circuit. Only when the connection is valid is the gas data sent quickly to prevent invalid transmission, so as to realize remote monitoring of gas data in smoldering fire environments.

[0085] For example, in the process of data transmission, traditional fire monitoring detects changes in the concentration of gases in the air using a fixed clock. A first clock provides a clock signal with second-level data segments for the periodic increase in gas concentration, and by associating the clock signal with the periodic physical changes in gas concentration, a fire alarm can be triggered within seconds.

[0086] For example, during data transmission, the segmentation circuit 300 performs second-level data segmentation, discretizing the continuous analog signal into second-level transmission signals, reducing transmission bandwidth and simultaneously reducing power consumption. Then, through frame structure encapsulation, it achieves fast transmission of second-level effective data, and also realizes frequency hopping communication. This reduces power consumption, increases data transmission rate, eliminates data transmission errors and interference, and also increases transmission distance.

[0087] For example, the current channel is either an RS485 bus channel formed by the RS485 communication interface 150 connected to the host computer, or a wireless communication channel of the 4G network communication module 170. If both channels are connected to the host computer simultaneously, a DMA buffer can be deployed in the current channel for hardware mapping and encapsulation. The generated second-level valid signal can be transmitted to the host computer through a sliding window protocol. In the event of a disconnection between the host computer and the RS485 communication interface 150 or the 4G network communication module 170, the buffer can also cache some data. At the same time, when there is no disconnection, the DMA buffer performs encapsulation delay, which can also make the hardware encapsulation mapping and data transmission to the host computer more synchronized.

[0088] Example 2:

[0089] like Figure 3 The diagram shows the circuit topology of an improved gas data transmission circuit system 100, which addresses the common problems of strong electromagnetic interference and weak signal detection in smoldering fire environments.

[0090] In this application:

[0091] During data acquisition, a multi-stage RC filter network 310 is deployed between the segmentation circuit 300 and the gas sensing device. The multi-stage RC filter network 310 includes operational amplifiers, each configured with a preset gain range.

[0092] The gas concentration simulation signal is filtered by a multi-stage RC filter network 310 to remove electromagnetic noise, and when there is a weak signal at the MV level in the gas concentration simulation signal, the weak signal is amplified through a preset gain range.

[0093] The operational amplifier includes a first-stage RC amplifier and a second-stage RC amplifier, as well as an amplification sensor. The first-stage RC amplifier is connected to the first amplifier 311 to amplify the analog signal of dust. The second-stage RC amplifier is connected to the second amplifier 312 to amplify the analog signal of gas.

[0094] In the embodiments of this application, the function of the multi-level RC filter network 310 is to suppress noise in the original analog signal and to amplify the weak signal (mV level) generated by the low concentration of gas in the early stage of smoldering fire, thereby solving the problem that small signals are easily submerged by noise. The data segmentation stage can then effectively extract valid data.

[0095] The multi-stage RC filter network 310 consists of resistors and capacitors connected in series. Each stage of the RC circuit forms a low-pass filter, allowing low-frequency signals with slowly changing gas concentrations to pass through by setting the cutoff frequency. The period of change in smoldering gas concentration is typically >1 second. It also filters out high-frequency electromagnetic noise. Cascading multiple stages further increases the filter slope and enhances noise suppression. This reduces the electromagnetic noise amplitude to below 1% of the signal amplitude, preventing data segmentation errors caused by noise. Compared to digital filtering, multi-stage RC filtering does not require processor resources and can complete preprocessing before the signal enters the ADC, reducing the complexity of subsequent software algorithms and ensuring real-time data segmentation down to the second level. The gas sensor 220 typically outputs a signal in the mV range during the early stages of smoldering fires, requiring adjustable gain amplification via an amplifier circuit. The preset gain range is set by a hardware resistor network. High gain is automatically enabled when the sensor output voltage is <50mV, and switches to low gain when it is ≥50mV to avoid signal saturation distortion. The amplified signal can be matched to the ADC's input range.

[0096] For example, when there is a smoldering fire signal: multi-level filtering adapts the weak signal and amplifies it to prevent the smoldering gas concentration simulation signal from being segmented incorrectly due to interference. Then, by dynamically matching the signal amplitude through a preset gain range, the weak signal can be dynamically amplified during the correct segmentation process. Instead of using a fixed weak signal method, the weak gas concentration sensing signal is accurately amplified, so that the weak gas concentration sensing signal is not distorted while noise is suppressed.

[0097] For example, during the amplification of the gas concentration signal, in the case of smoldering, the gas concentration signal is weak. The multi-stage RC filter network 310 amplifies the weak signal with strong gain. Later, as the gas concentration becomes more concentrated in the case of smoldering, the gas concentration analog signal gradually becomes weak and the gain increases. This makes the signal divided by the segmentation circuit 300 have the same frequency but increased amplitude during data transmission. This increases the current and voltage of the weak signal and makes it consistent with the strong signal, reducing signal distortion. The segmentation circuit 300 does not need to be adjusted to adapt to the weak signal.

[0098] Example 3:

[0099] like Figure 3 The diagram shows the circuit topology of an improved gas data transmission circuit system 100 according to this application. The main components of the segmentation circuit 300 include a capacitor array and an analog switch.

[0100] In the embodiments of this application, the capacitor array is used to store analog signal charge, and the temporary storage of signals of different amplitudes is achieved by capacitance matching; the analog switch controls the signal path by turning on / off the MOS transistor, and is triggered by the rising edge of the first clock signal to realize fast signal switching and slicing.

[0101] For example, the capacitor array uses multiple capacitance values, and the signal amplitude is matched by address line selection to achieve signal temporary storage. For example, 8 capacitance values ​​are preferred. The analog switch uses a low on-resistance switching device to reduce signal loss and achieve fast switching. The combination of the two reduces signal distortion during switching and can prevent the 300 response delay of the segmentation circuit from causing slicing errors.

[0102] When the analog switch is triggered by the rising edge of the first clock signal, a second-level trigger signal is generated, and second-level signal slicing is performed to determine the segmented signal. During the second-level signal slicing process, the switching noise is suppressed in real time by the LC network. The second-level signal slicing process completes no less than 500 signal slices per second, and the timestamp accuracy of the second-level trigger signal is less than 10ms.

[0103] In the embodiments of this application, the first clock signal is a clock signal provided by the main controller MCU110, which is used to set a high-precision time base for data segmentation to ensure a second-level time granularity. The first clock uses a high-precision RTC built into the MCU or an external crystal oscillator, and generates a 1Hz second-level trigger pulse through a frequency divider circuit. The timestamp accuracy is determined by the frequency deviation of the clock source.

[0104] For example, the trigger signal is simultaneously synchronized to the segmentation circuit 300 and the main controller MCU110 to ensure a unified time base. An accuracy of less than 10ms ensures that the timestamp error of second-level data frames is negligible and can meet the timing analysis requirements of second-level data transmission. A timestamp accuracy of less than 10ms indicates a timescale much smaller than the change in smoldering gas concentration in a fire, ensuring the periodic stability of the data segmentation. This makes the deviation between the timestamp and the actual sampling time negligible, resulting in more accurate timing analysis when the host computer calculates the rate of change of gas concentration in a smoldering environment.

[0105] For example, when the second-level trigger signal is high, the analog switch is turned on, and the gas concentration analog signal is charged through the capacitor array 321, discretizing the continuous signal into analog packets of time slices. The charge storage speed of the capacitor array 321 is much faster than that of software-controlled ADC sampling, preventing signal loss caused by processor response delay. The low leakage current characteristics of the ceramic capacitors ensure that the amplitude attenuation of the slice signal is ≤0.1% during the holding period.

[0106] For example, the second-level trigger signal is a gating signal used to control the conduction of the analog switch. Therefore, the path is only opened when a valid signal is input. Then, the input gas concentration analog signal is continuously compared, reducing power consumption. The capacitor array temporarily stores the charge of the analog signal, and the analog switch controls the on / off state of the signal path, so that continuous analog signals can be physically sliced ​​through the capacitor array and analog switch, preventing delays in software control.

[0107] In one embodiment, the analog switch includes a first CMOS analog switch chip 322 and a second CMOS analog switch chip 323.

[0108] For example, when the analog switch is triggered by the rising edge of the first clock, a second-level signal slicing is performed to determine the segmented signal; wherein, during the second-level signal slicing process, the switching noise is suppressed in real time by the LC network, and no less than 500 signal slices are completed per second during the second-level signal slicing process;

[0109] For example, to prevent information loss due to signal fluctuations within a single second, the rising edge of the first clock triggers an analog switch to rapidly switch at a frequency of 500Hz, dividing the analog signal within one second into 500 consecutive slices. An LC network acts as a bandpass filter, with its center frequency matched to the slice frequency, filtering out switching noise introduced during the slicing process. A slice density of 500 times / second can capture minute fluctuations in gas concentration within a single second, such as a 0.5% instantaneous change in concentration at the initial stage of smoldering, without the information loss that occurs with traditional 1-times / second sampling.

[0110] For example, the rising edge of the first clock signal is used as the trigger edge, which can control the analog switch to switch rapidly at a fixed frequency, cutting the continuous analog signal within 1 second into 500 discrete signal slices. Each slice is a 2ms signal segment, and the segmented signal can accurately determine the subtle fluctuations in gas concentration every second. By combining the slices and the second-level period, the amount of data and the integrity of information can be balanced.

[0111] For example, an LC network can suppress and reduce noise during the slicing process, improving the signal-to-noise ratio of the segmented signal. Then, the switching frequency of the control analog switch is determined by the high-frequency trigger signal of the first clock, ensuring that slicing occurs no less than 500 times per second, and the slicing density is determined by the clock frequency and the response speed of the analog switch.

[0112] For example, in the process of acquiring second-level valid data, the analog slice signal is digitized and the effective value is calculated. Combined with the timestamp, structured second-level data is formed. The ADC processor 400 digitizes the segmented signal at a sampling rate of 1MSPS, with each slice signal corresponding to 2000 digital sampling points. The processor summarizes the digital values ​​of 500 slices at second-level cycles, or even more than 1000 slices. The effective value is extracted by the moving average algorithm and embedded with the timestamp generated by the first clock to form structured second-level data. This not only preserves the signal characteristics within a single second but also compresses the data volume, ensuring high precision while achieving low transmission load.

[0113] The segmented signal is converted into a digital quantity at a sampling rate of 1MSPS using an analog-to-digital converter. The digital quantity is then divided into segments according to a second-level period. The valid values ​​in the digital quantity are extracted and timestamps are embedded to generate second-level valid data.

[0114] In one implementation, 1 MSPS represents digitizing the segmented signal at a sampling rate of one million times per second, with each slice corresponding to multiple digital sampling points, such as 2000. This achieves high-precision quantization of the samples. When segmenting the digital data, the digitized slices are aggregated according to a second-level period of the first clock, thereby dividing the continuous digital stream with timestamp alignment into one data block per second. This structured segmentation of the digital data reduces redundancy in data transmission and storage. The generation of second-level valid data is achieved through a digital filtering algorithm. This algorithm uses the average and maximum values ​​mentioned in the second-level digital blocks from the moving average and peak detection data, and embeds the timestamp generated by the first clock to form a structured data frame.

[0115] For example, the LC network suppresses switching noise. During the second-level signal slicing process, there are more than 500 high-density switches per second. The LC network suppresses the switching noise of high-frequency switching. Combined with the second-level trigger signal, the segmentation circuit 300 can achieve high-frequency slicing and acquire low-noise second-level effective data at the same time during the acquisition of second-level effective data. Combined with the digital acquisition of effective data with a sampling rate of 1MSPS of analog-to-digital converter and the embedding of timestamps, the second-level effective data has an extremely high compression ratio while retaining all effective features without distortion, making it faster to encapsulate and transmit.

[0116] Example 4:

[0117] like Figure 3 As shown, the circuit principle topology diagram of the improved gas data transmission circuit system 100 of this application is shown. The capacitor array 321 is composed of multiple sub-arrays. The input terminal of the capacitor array is connected to the signal conditioning circuit 320 of the gas sensor 220 through gold-plated pins, and its output terminal is connected to the analog switch through a low-impedance ribbon cable.

[0118] Each subarray consists of at least eight high-precision ceramic capacitors connected in parallel, each subarray receives a single gas analog signal, and the output of each subarray is connected in series with a magnetic bead inductor.

[0119] In the embodiments of this application, the capacitor array 321, through its physical structure design, can achieve isolated transmission and low-loss connection in the presence of multiple gas signals, enabling multi-channel parallel operation. It comprises multiple modular subarrays, each corresponding to one gas sensor 220. For example, the carbon monoxide detection subarray corresponds only to CO; different subarrays are physically isolated to prevent cross-interference between different gas sensing signals; the pins of the capacitor array 321 are gold-plated to form a low-impedance, oxidation-resistant contact interface, reducing contact resistance and electrochemical corrosion risk in the signal transmission path. The low-impedance flatbed cable uses a twisted-pair shielded cable to reduce skin effect loss and electromagnetic radiation coupling in high-frequency signal transmission.

[0120] For example, the ceramic capacitors in the subarray exhibit high-frequency response and low loss tangent; eight capacitors connected in parallel increase the total capacitance by eight times, while reducing the equivalent series resistance, thereby improving charge storage efficiency and charging / discharging speed. Each subarray corresponds one-to-one with a sensor, and electromagnetic isolation between channels is achieved through grounding isolation strips in the PCB layout. The ferrite bead inductor utilizes high-frequency hysteresis loss to absorb switching noise; its impedance increases with frequency, and it exhibits almost no attenuation for low-frequency gas signals.

[0121] For example, multiple subarrays are physically isolated, and each subarray corresponds to the acquisition of a single gas signal. When used alone, it can achieve the highest accuracy in acquiring single gas data. When acquiring multiple gas signals, because the different subarrays are physically isolated, the mixed gas can accurately detect the concentration data of a single gas. After the accurate single gas concentration data is fused, a gas signal fusion is generated. During fusion, because there is no interference from the mixed gas factors in the acquisition stage, the accuracy of the acquired data is improved.

[0122] For example, the gold-plated pins have a low resistance effect, which, together with the low transmission loss of the low-impedance cable, forms a low-loss transmission link. When performing gas concentration detection, the accuracy of the gas concentration analog signal can be improved due to the low-loss transmission link.

[0123] For example, when high-precision ceramic capacitors are connected in parallel, the circuit has static stability, and the ferrite bead inductor can achieve dynamic noise suppression. When the two are combined in the process of converting the gas concentration analog signal into a digital signal, the accuracy of the digital signal is improved, the early warning effect of smoldering is stronger, and the signal-to-noise ratio of the signal transmission link is reduced.

[0124] For example, by receiving an independent gas concentration analog signal for each subarray, multi-signal isolation can be achieved. Combined with the noise suppression of the series-connected magnetic bead inductors and the improvement of the accuracy of the gas concentration analog signal by the high-precision ceramic capacitors, crosstalk-free data transmission can be achieved when transmitting multiple gases.

[0125] Example 5:

[0126] like Figure 3 As shown, the circuit principle topology diagram of the improved gas data transmission circuit system 100 of this application is shown. The analog switch includes a MOS analog switch chip, and the input channels of the CMOS analog switch chip correspond one-to-one with the sub-array.

[0127] The CMOS analog switch chip has a π-type filter connected in series at its output terminal and is electrically isolated from the input terminal of the analog-to-digital converter through an optocoupler isolation chip. The optocoupler isolation chip includes a first optocoupler isolation chip 324 and a second optocoupler isolation chip 325. The first optocoupler isolation chip 324 is used to realize the independent switching of multiple dust signals, and the second optocoupler isolation chip 325 isolates and realizes the independent switching of multiple gas signals.

[0128] A first sampling resistor is connected in parallel to the common terminal of the CMOS analog switch chip. The first sampling resistor is used to acquire the conduction status signal of the input channel.

[0129] In the embodiments of this application, the CMOS analog switch chip is used to prevent contact resistance fluctuations and crosstalk of the mechanical switch. The independent switching of multiple dust signals is achieved through the channel isolation of the first CMOS analog switch chip 322; and the independent switching of multiple gas signals is achieved through the channel isolation of the second CMOS analog switch chip 323.

[0130] CMOS analog switch chips integrate a field-effect transistor switch array, and the channel is turned on / off by digital control signals.

[0131] In the embodiments of this application, the input channels correspond one-to-one with the sub-arrays, ensuring that each gas signal is transmitted through an independent MOSFET switch to prevent cross-interference of multiple gas signals, achieve high-frequency slice switching, and avoid mechanical wear problems.

[0132] For example, a π-type filter specifically filters out high-frequency spike noise generated by switch switching, and the gas concentration analog signal is used for purification before analog-to-digital conversion. A π-type low-pass network composed of two ceramic capacitors and one ferrite bead inductor filters out charge injection noise and clock feedthrough noise generated by CMOS switch switching.

[0133] In the embodiments of this application, the optocoupler chip transmits signals via infrared light, and there is no direct electrical connection between the input and output terminals, thus blocking loop interference and high-voltage spikes. For example, a first sampling resistor is connected in parallel between the common output terminal of the analog switch and ground. When an input channel is conducting, the signal current flows through the first sampling resistor, generating a voltage drop. This voltage is acquired through an additional analog-to-digital conversion channel to determine whether the channel is conducting normally, thereby monitoring the conduction status of the switch channel in real time and avoiding faults such as channel sticking (continuous conduction) and open circuit (inability to conduct).

[0134] For example, the input channels of the CMOS analog switch chip correspond one-to-one with the sub-arrays. Therefore, when there is a gas concentration analog signal input, the independent channels can reduce crosstalk. Then, the π-type filter specifically suppresses high-frequency switching noise, thereby reducing the signal-to-noise ratio by at least 60% and improving the fidelity of the gas concentration analog signal.

[0135] For example, the π-type filter first attenuates high-frequency switching noise to prevent high-frequency noise from entering the isolator, and then blocks common-mode interference through optical isolation to prevent noise from being reverse-coupled after isolation, thus forming a dual anti-interference mechanism of active filtering and passive isolation, thereby improving the acquisition of gas concentration analog signals.

[0136] For example, a CMOS analog switch chip, operating at a slice efficiency of 500 times per second, can monitor the switching status in real time through sampling resistors and status acquisition. In the event of a fault, the high-speed switching allows for instantaneous reset and fault elimination. Once a fault is detected, a backup channel can be switched immediately.

[0137] For example, during the signal segmentation process, because the input channels and sub-arrays correspond one-to-one, there is no aliasing between signals. Consequently, the output signal passes through the first sampling resistor connected in parallel to the common terminal, preventing the different channels from sticking together and data transmission errors. Thus, under the on-state signal, the second-level valid data obtained by the segmentation circuit 300 segmentation will not be faulty.

[0138] Example 6:

[0139] like Figure 3 As shown, the circuit topology diagram of the improved gas data transmission circuit system 100 of this application shows that the second-level effective data encapsulation is processed by the hardware acceleration module integrated in the main controller MCU 110; wherein,

[0140] The hardware acceleration module includes a frame structure generator and a data alignment circuit. The frame structure generator splices the frame type identifier, timestamp, valid data segment and checksum according to a preset sequence. The data alignment circuit directly maps the second-level data collected by the sensor to the corresponding fields of the protocol frame, replacing the software encapsulation process with hardware logic.

[0141] In the embodiments of this application, the hardware acceleration module is independent of the CPU core. It reads second-level valid data from the data buffer through direct memory access and completes the encapsulation without CPU intervention. The clock frequency of the hardware acceleration module is consistent with that of the processor core, enabling parallel data processing and meeting the total time consumption from second-level data generation to encapsulation completion.

[0142] The frame structure generator uses a hardware state machine to concatenate protocol frames in a fixed format with a preset sequence. The state machine is triggered periodically, reading data from each field of the register sequentially and concatenating them into a continuous bit stream.

[0143] The data alignment circuit uses a hardware address mapping table to directly map the physical address of the sensor data buffer to the field offset of the valid data segment in the protocol frame, avoiding multiple memory copies in software encapsulation. The data alignment circuit has a built-in address mapping register that pre-configures the target offset address of each sensor data point in the protocol frame. When second-level data is generated, the circuit directly reads the physical address of the sensor data buffer via a DMA request and writes it to the corresponding field in the protocol frame buffer according to the mapping relationship. The entire process is controlled by hardware timing and does not require CPU instruction execution, making the hardware unaffected by software interrupts or task scheduling. It can still complete data encapsulation even when electromagnetic interference causes CPU malfunctions.

[0144] For example, during the encapsulation process of gas concentration signal data, the frame structure generator uses software to drive data alignment, realizes format splicing, and encapsulates second-level valid data. Therefore, it reduces the data error rate, reduces the data volume, and reduces power consumption and data processing time. The data alignment circuit directly maps the spliced ​​data to the corresponding field of the protocol frame buffer through a hardware address mapping table, so that the data encapsulation method achieves synchronous mapping and directly encapsulates and transmits data through hardware timing.

[0145] For example, during the process of uploading second-level valid data to the host computer, a frame structure generator is used to generate the overall format of the second-level valid data to improve throughput. Then, the data alignment circuit maps and encapsulates the collected second-level valid data through a preset address mapping table to generate second-level valid data frames. This not only improves throughput but also increases the transmission speed of the encapsulated second-level valid data frames.

[0146] Example 7:

[0147] The current channel deployment uses time-space gating logic; wherein...

[0148] The time-space gating logic includes a channel state detection circuit, which monitors the differential voltage signal of the RS485 bus in real time. When it detects a connection response signal sent by the host computer, it automatically generates a clock enable level until the current second-level data frame transmission is completed.

[0149] The duration of the clock enable level is dynamically determined by the bit width and transmission rate of the RS485 protocol frame.

[0150] In this application, the time-space gating logic integrated into the RS485 bus interface controller uses an AND gate circuit to control whether the clock signal is input to the communication module. When the enable signal is high, the clock passes through; when the enable signal is low, the clock is cut off, and the communication module stops working. This intermittent shutdown of the clock signal reduces high-frequency electromagnetic radiation.

[0151] The RS485 bus uses differential voltage transmission. The channel status detection circuit has a built-in high-speed comparator to monitor the bus differential voltage in real time. When a dominant level is detected, a status trigger signal is output to the time-space gating logic. The host computer's connection response signal is a dominant level. After the detection circuit is triggered, the time-space gating logic latches the enable signal through a D flip-flop. The RS485 bus... Figure 8 The circuit topology diagram of the RS485 communication interface 150 is shown below.

[0152] Simultaneously, the data frame transmission state machine begins counting. When the frame end marker is detected, the enable signal is automatically pulled low, and the clock is turned off, ensuring a stable clock output throughout the entire data frame transmission and avoiding frame format errors caused by clock interruptions. The bit width and transmission rate of the RS485 protocol frame determine the transmission time of a single frame. The time-space gating logic has a built-in multiplier circuit, which dynamically adjusts the duration of the enable signal in real time through hardware calculation.

[0153] In one embodiment, when second-level data frames are transmitted through the current channel, i.e., through intermittent communication, the channel is controlled to supply power according to data transmission requirements, reducing power loss of sensing devices without external power supply during data transmission. During the transmission of second-level data frames, a channel state detection circuit with spatiotemporal gating logic detects the differential signal during data transmission to determine whether there is a response delay, thereby improving the connection speed to the host computer and preventing strong electromagnetic interference in smoldering environments. A clock enable level is generated only when a connection response signal is received from the host computer. The clock enable level is dynamically calculated in real time based on the bit width and transmission rate of the RS485 protocol frame, thereby controlling the duration of the clock enable level to prevent excessively long durations that would result in ineffective power consumption. The current signal is controlled to transmit data until the second-level data frame transmission is complete, preventing excessive interference from continuously open channels and potential tail frame loss during fixed-duration transmission.

[0154] For example, during the second-level effective data transmission to the host computer, the differential voltage signal feedback connection acknowledgment signal enables the host computer to automatically respond during data transmission. Then, through the clock enable level, complete data transmission is achieved. In this process, the duration of the clock enable level is dynamically determined by the bit width and transmission rate of the RS485 bus protocol frame. This enables low-power transmission of complete data and reduces the intermediate steps of the detection circuit outputting to the CPU and then the CPU controlling the gating to achieve data transmission to the host computer.

[0155] Example 8:

[0156] The current channel also deploys security gating logic and state linkage circuitry; among which,

[0157] The security gating logic is used to generate a frame transmission status signal when the channel state detection circuit detects a differential voltage signal;

[0158] The status linkage circuit receives the frame transmission status signal and the host computer connection response signal from the RS485 bus. When both the frame transmission status signal and the host computer connection response signal are at a valid level, the clock gating enable terminal is locked through the safety gating logic until the frame transmission completion signal is fed back and the lock is released. During this period, the execution of any clock disable command is prohibited.

[0159] In the embodiments of this application, the security gating logic is independent of the spacetime gating logic, and the clock enable signal is controlled secondaryally through a hardware interlock circuit. When the locking condition is met, EN is forcibly kept high, blocking any external disable commands. The frame transmission status signal comes from the transmit flag bit of the RS485 bus and remains high during each frame transmission. The host computer connection status signal comes from the periodic heartbeat response of the host computer, and the connection validity is determined by a hardware comparator. The status linkage circuit synchronizes the two signals to the same clock domain through a flip-flop, avoiding metastability and ensuring signal timing consistency.

[0160] For example, the two signals are judged by gate logic. Since both are high, the output is high, triggering the SR latch to be set. Its output is directly connected to the enable terminal of the space-time gating logic, forcing EN to remain high. After the RS485 bus transmission is completed, a frame end signal is output, triggering the SR latch to be reset and releasing the forced lock on the EN terminal. During the lockout period, the disable instruction input of the space-time gating logic is shielded by a NOR gate and cannot affect the state of the EN terminal.

[0161] For example, during the transmission of second-level valid signals, the clock gating enable terminal is controlled to transmit data by using two signals, namely the frame transmission status signal and the host computer connection response signal, which are valid at the same time. The execution of any clock disable command is prohibited, so that the transmission of second-level valid signals will not be interrupted by interference or system crashes. The lock is released after the frame transmission completion signal feedback. This can achieve zero-redundancy locking and make the locking duration more appropriate.

[0162] Example 9:

[0163] In other embodiments of this application, the second-level gas data transmission system may also employ the second-level data transmission method described in embodiments 1 to 8 above. In some embodiments, the second-level gas data transmission system includes:

[0164] Gas signal acquisition module: used to acquire simulated gas concentration signals in a smoldering fire environment in real time through gas sensing devices; wherein, the sampling frequency is positively correlated with the gas concentration;

[0165] Second-level data segmentation module: used to segment the gas concentration analog signal into second-level data through the segmentation circuit 300 via the first clock signal, generating second-level valid data; wherein, the first clock signal represents the trigger signal at the initial moment of the periodic increase of gas concentration, and the second-level valid data is an effective digital signal representing the gas concentration state within one second.

[0166] Data upload module: Used by the main controller to control the hardware mapping and encapsulation of second-level valid data according to the frame structure, and generate second-level data frames for the current channel; when the current channel is connected to the host computer, the second-level valid data is transmitted to the host computer.

[0167] It should be understood that the specific process of the second-level gas data transmission system executing the corresponding steps of the above-mentioned second-level gas data transmission method is described in Examples 1 to 8. For the sake of brevity, it will not be elaborated here.

[0168] Example 10:

[0169] In other embodiments of this application, see [reference]. Figure 3 This application also proposes a second-level gas data transmission device, which can also adopt the second-level data transmission method in the above embodiments 1 to 8:

[0170] Gas sensing devices are deployed in the fire monitoring area to collect simulated gas concentration signals;

[0171] A multi-stage RC filter network 310 is electrically connected to the output of the gas sensing device and filters and amplifies the gas concentration analog signal.

[0172] The segmentation circuit 300 is electrically connected to the output of the multi-stage RC filter network and performs second-level data segmentation on the filtered and amplified gas concentration analog signal.

[0173] The main controller is electrically connected to the segmentation circuit 300 and controls the segmentation circuit 300 to perform second-level data segmentation according to the first clock signal, thereby acquiring the second-level valid data after segmentation. In actual implementation, the main controller is also connected to the storage chip 140 to adjust the gas concentration reference corresponding to the first clock signal and the segmentation logic of the segmentation circuit 300, such as... Figure 7 As shown.

[0174] The 4G network communication module 170 is electrically connected to the output of the main controller and wirelessly connected to the host computer. The 4G network communication module 170, as shown... Figure 10 As shown.

[0175] The RS485 communication interface 150 is electrically connected to the output of the main controller and the input of the host computer. In actual implementation, an RJ45 network interface 160 is also included, such as... Figure 9 As shown.

[0176] The power supply circuit 120 is electrically connected to the main controller, the multi-stage RC filter network 310, the segmentation circuit 300, the 4G network communication module 170, and the RS485 communication interface 150, respectively. The power supply circuit is as follows: Figure 5 As shown, the power supply circuit 120 includes a power conversion circuit DC-DC130, which is used to convert the power supply from the battery or external power supply to generate power for modules such as the main controller.

[0177] It should be understood that the specific process of the second-level gas data transmission device executing the corresponding steps of the above-mentioned second-level gas data transmission method is described in Examples 1 to 8. For the sake of brevity, it will not be elaborated here.

[0178] Obviously, those skilled in the art can make various modifications and variations to this invention without departing from its spirit and scope. Therefore, if these modifications and variations fall within the scope of the claims of this invention and their equivalents, this invention also intends to include these modifications and variations.

Claims

1. A method for transmitting gas data at the second level, characterized in that, It includes a gas data transmission circuit; wherein the gas transmission circuit includes a main controller, and the main controller is connected to a segmentation circuit; The method includes: The gas concentration simulation signal in the smoldering fire environment is collected in real time by gas sensing equipment; the sampling frequency is positively correlated with the gas concentration. The gas concentration analog signal is divided into second-level data by a segmentation circuit using a first clock signal to generate second-level valid data. The first clock signal represents the trigger signal at the initial moment of the periodic increase in gas concentration, and the second-level valid data is an effective digital signal representing the gas concentration state within one second. The main controller performs hardware mapping and encapsulation of second-level valid data according to the frame structure to generate second-level data frames for the current channel; when the current channel is connected to the host computer, the second-level valid data is transmitted to the host computer. A multi-stage RC filter network is deployed between the segmentation circuit and the gas sensing device. The multi-stage RC filter network includes operational amplifiers, each configured with a preset gain range. The gas concentration simulation signal is filtered to remove electromagnetic noise by a multi-stage RC filter network, and when there is a weak signal at the MV level in the gas concentration simulation signal, the weak signal is amplified through a preset gain range. The segmentation circuit includes a capacitor array and analog switches; wherein... When the analog switch is triggered by the rising edge of the first clock signal, a second-level trigger signal is generated, and second-level signal slicing is performed to determine the segmented signal. During the second-level signal slicing process, the switching noise is suppressed in real time by the LC network. The second-level signal slicing process completes no less than 500 signal slices per second, and the timestamp accuracy of the second-level trigger signal is less than 10ms. The segmented signal is converted into a digital quantity at a sampling rate of 1MSPS using an analog-to-digital converter. The digital quantity is then divided into segments according to a second-level period. The valid values ​​in the digital quantity are extracted and timestamps are embedded to generate second-level valid data.

2. The second-level gas data transmission method as described in claim 1, characterized in that, The capacitor array is composed of multiple sub-arrays. The input terminal of the capacitor array is connected to the signal conditioning circuit of the gas sensor through gold-plated pins, and its output terminal is connected to the analog switch through a low-impedance ribbon cable. Each subarray consists of at least eight high-precision ceramic capacitors connected in parallel, each subarray receives a single gas analog signal, and the output of each subarray is connected in series with a magnetic bead inductor.

3. The second-level gas data transmission method as described in claim 2, characterized in that, The analog switch includes a CMOS analog switch chip, and the input channels of the CMOS analog switch chip correspond one-to-one with the sub-array; The output of the CMOS analog switch chip is connected in series with a π-type filter and is electrically isolated from the input of the analog-to-digital converter through an optocoupler isolation chip. A first sampling resistor is connected in parallel to the common terminal of the CMOS analog switch chip. The first sampling resistor is used to acquire the conduction status signal of the input channel.

4. The second-level gas data transmission method as described in claim 1, characterized in that, The main controller integrates a hardware acceleration module for encapsulation and processing; wherein... The hardware acceleration module includes a frame structure generator and data alignment circuitry; The frame structure generator concatenates the frame type identifier, timestamp, valid data segment, and checksum according to a preset sequence. The data alignment circuit directly maps the second-level valid data collected by the sensor to the corresponding fields in the protocol frame, replacing the software encapsulation process with hardware logic.

5. The second-level gas data transmission method as described in claim 1, characterized in that, The current channel deployment uses time-space gating logic; wherein... The time-space gating logic includes a channel state detection circuit, which monitors the differential voltage signal of the RS485 bus in real time. When it detects a connection response signal sent by the host computer, it automatically generates a clock enable level until the current second-level data frame transmission is completed. The duration of the clock enable level is dynamically determined by the bit width and transmission rate of the RS485 bus protocol frame.

6. The second-level gas data transmission method as described in claim 5, characterized in that, The current channel also deploys security gating logic and state linkage circuitry; wherein... The security gating logic is used to generate a frame transmission status signal when the channel state detection circuit detects a differential voltage signal; The status linkage circuit receives the frame transmission status signal and the host computer connection response signal from the RS485 bus. When both the frame transmission status signal and the host computer connection response signal are at a valid level, the clock gating enable terminal is locked through the safety gating logic until the frame transmission completion signal is fed back and the lock is released. During this period, the execution of any clock disable command is prohibited.

7. A second-level gas data transmission system, applicable to the second-level gas data transmission method of any one of claims 1 to 6, the system comprising: Gas signal acquisition module: used to acquire simulated gas concentration signals in a smoldering fire environment in real time through gas sensing devices; wherein, the sampling frequency is positively correlated with the gas concentration; Second-level data segmentation module: used to segment the gas concentration analog signal into second-level data through a segmentation circuit and a first clock signal to generate second-level valid data; wherein, the first clock signal represents the trigger signal at the initial moment of the periodic increase of gas concentration, and the second-level valid data is an effective digital signal representing the gas concentration state within one second. Data upload module: Used by the main controller to control the hardware mapping and encapsulation of second-level valid data according to the frame structure, and generate second-level data frames for the current channel; when the current channel is connected to the host computer, the second-level valid data is transmitted to the host computer.

8. A second-level gas data transmission device, applicable to the second-level gas data transmission method according to any one of claims 1 to 6, the device comprising: Gas sensing devices are deployed in the fire monitoring area to collect simulated gas concentration signals; A multi-stage RC filter network is electrically connected to the output of the gas sensing device and filters and amplifies the gas concentration analog signal. The segmentation circuit is electrically connected to the output of a multi-stage RC filter network and performs second-level data segmentation on the filtered and amplified gas concentration analog signal. The main controller is electrically connected to the segmentation circuit and controls the segmentation circuit to perform second-level data segmentation according to the first clock signal, and obtain the second-level valid data after the second-level data segmentation; The 4G network communication module is electrically connected to the output of the main controller and wirelessly connected to the host computer. The RS485 communication interface is electrically connected to the output of the main controller and the input of the host computer. The power supply circuit is electrically connected to the main controller, multi-stage RC filter network, segmentation circuit, 4G network communication module, and RS485 communication interface, respectively.

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