A highly stable wireless network transmission system and method for use in coal mining

Abstract

This invention relates to the field of industrial wireless communication technology, specifically a highly stable wireless network transmission system and method for use in coal mining. The system includes a broadcast determination module, a path activation module, a hop point selection module, a link construction module, and a transmission output module. This invention collects the power status and channel response records of underground equipment and constructs broadcast initiation conditions. It can determine the trigger for communication broadcasts based on energy consumption and response effectiveness, thereby initiating path probing operations under the dual protection of acceptable power levels and communication activity. It evaluates the performance of responding devices based on signal strength, remaining power, and hop distance, and accurately selects recommended paths using normalization and multi-parameter sorting algorithms, effectively achieving channel load balancing and inter-device collaborative communication. Furthermore, it selects hop point device combinations based on the consistency of signal change trends, enhancing path stability and time continuity.

Description

Technical Field

[0001] This invention relates to the field of industrial wireless communication technology, and in particular to a highly stable wireless network transmission system and method for use in coal mining. Background Technology

[0002] The field of industrial wireless communication technology involves building wireless communication networks in industrial environments to achieve efficient data transmission and coordinated control among devices, systems, and personnel. This includes ensuring the stability of wireless communication signals, optimizing network coverage, anti-interference design in harsh environments, controlling transmission latency and reliability, and adapting communication protocols for specific industrial scenarios.

[0003] Among them, the wireless network transmission system applied to coal mining refers to the data communication between mining equipment, monitoring terminals and dispatch centers in the underground environment, in order to solve the problems of complex communication environment, multiple interference sources, and severe signal attenuation and frequent communication interruptions caused by the closed terrain structure in the mining operation area.

[0004] In downhole environments, existing technologies primarily rely on fixed communication paths between devices for data forwarding, lacking dynamic assessment mechanisms for device energy consumption and channel stability. This leads to some devices passively participating in communication broadcasting even when power is insufficient or channel activity is reduced, easily causing path interruptions or data packet loss. Furthermore, the path selection process fails to integrate multi-dimensional indicators such as signal quality, energy consumption, and hop distance prediction, resulting in path recommendations that often lack accuracy and timeliness. In cases of severe signal fluctuations or sudden interference, frequent link switching or node response delays can easily occur. In addition, due to the lack of similarity analysis of the signal trajectories between adjacent devices over time, it is difficult to identify hop combinations with consistent signal trends and stable communication in a timely manner, leading to fluctuation risks in the link structure. This, in turn, affects the continuity of downhole communication and the system's adaptability to complex operating environments. Summary of the Invention

[0005] The purpose of this invention is to overcome the shortcomings of the existing technology and propose a highly stable wireless network transmission system and method for use in coal mining.

[0006] To achieve the above objectives, the present invention adopts the following technical solution: a highly stable wireless network transmission system for coal mining, the system comprising:

[0007] The broadcast determination module collects the power status and channel response records of the underground relay wireless transmission equipment, compares them with the upper limit of average power consumption and the threshold of the number of channel responses within a specified broadcast period, and constructs a broadcast start identifier.

[0008] The path activation module generates a corresponding broadcast control command based on the broadcast initiation identifier, activates the response process of the downhole adjacent communication devices, sorts the adjacent communication devices that respond to the broadcast control command, and obtains the recommended path for the devices.

[0009] The jump point filtering module filters adjacent communication devices used for data forwarding as relay communication devices based on the device recommended path, judges the consistency of the data trajectory of the signal strength of adjacent devices in the relay communication device sequence over time, and generates a jump point path sequence.

[0010] The link construction module establishes an underground wireless communication link structure through the jump point path sequence, instructs the relay communication device to collect communication status information, and obtains a path communication status dataset.

[0011] The transmission output module obtains the wireless network transmission result based on the path communication status dataset and all status information of the relay communication device during the transmission process.

[0012] The present invention improves upon the following: the broadcast initiation identifier includes a trigger condition status, a broadcast execution identifier, and a path determination result; the broadcast control command includes a channel scheduling command, a response activation information, and a path detection flag; the device recommended path includes a list of responding devices, a path hop count sorting, and a channel feedback set; the hop point path sequence includes a relay device sequence structure, a signal trajectory continuity relationship, and path hop order information; and the wireless network transmission result includes a link topology structure, a device status summary, and a communication process data record.

[0013] The present invention is improved in that the broadcast determination module includes:

[0014] The power identification submodule collects power status data of the downhole relay wireless transmission equipment, obtains the energy consumption data set of the same type of equipment in the current cycle in the working area, extracts the maximum value in the set as the upper limit of the average power consumption, and makes a numerical range judgment based on the upper limit and the collected power status to generate a power status comparison result.

[0015] The channel recording submodule collects channel response records of underground relay wireless transmission equipment within a specified broadcast period, extracts the number of channel responses in each period and compares them with a set response count threshold to filter valid channel response records.

[0016] The threshold comparison submodule determines whether the two data points simultaneously reach the set standards of the average power consumption limit and the channel response count threshold based on the power status comparison result and the valid channel response record. If both conditions are met, a broadcast start flag is generated.

[0017] The present invention is improved in that the path activation module includes:

[0018] The instruction generation submodule, based on the broadcast start identifier, determines that the state is broadcastable, and then the current downhole relay wireless transmission device issues an instruction to construct broadcast control information and sets control parameters to trigger the path detection process, thereby generating broadcast control instructions.

[0019] The device response submodule, based on the broadcast control command, activates the downhole adjacent communication devices within the current device communication range to execute the response process, and collects three parameters returned by the device during the response process: received signal strength, power status and predicted jump distance, to generate a path evaluation parameter set;

[0020] The path ranking submodule, based on the path evaluation parameter set, performs normalization processing on the three parameters respectively, and ranks the paths corresponding to each downhole adjacent communication device according to the preset evaluation criteria using the TOPSIS ranking algorithm, and selects the recommended path for the device based on the ranking results.

[0021] The present invention is improved in that the jump point filtering module includes:

[0022] The candidate construction submodule filters downhole adjacent communication devices with data forwarding capabilities according to the recommended path order of the devices, and generates a candidate relay sequence;

[0023] The trajectory extraction submodule collects a continuous data sequence of the received signal strength changing over time between each adjacent device in the candidate relay sequence, and generates a set of signal change trajectories;

[0024] The consistency judgment submodule inputs the continuous data sequence of the received signal strength of each pair of adjacent devices in the signal change trajectory set as a function of time into the longest common subsequence algorithm, compares the structural similarity between adjacent trajectories, filters the device combinations with consistent change trends, and generates a jump point path sequence.

[0025] The present invention is improved in that the link construction module includes:

[0026] The path establishment submodule establishes an underground wireless communication link structure from the broadcasting device to the receiving device terminal according to the jump point arrangement order of the jump point path sequence, and generates a communication link structure.

[0027] The instruction issuing submodule sends communication status acquisition instructions to all relay communication devices according to the node order in the communication link structure, configures acquisition task items and specifies the execution order, and generates a status acquisition task set.

[0028] The status acquisition submodule integrates the data collected by each relay communication device in the status acquisition task set, including its own transmission time, response delay fluctuation, signal holding time, and data error rate during the communication process, to generate a path communication status dataset.

[0029] The present invention is improved in that the transmission output module includes:

[0030] The jump point combination submodule extracts the jump point sequence relationship and corresponding status of each relay communication device in the path communication status dataset, associates and combines the transmission response information between device jump points, and generates a jump point combination structure set.

[0031] The structure assembly submodule calls the jump point combination structure set, maps the jump point sequence and state parameter combination to the underground wireless network topology, and constructs the transmission structure model.

[0032] The result generation submodule calls the transmission structure model to organize and summarize the hop sequence and parameter structure in the path, and outputs the valid path segment content according to the connected hop status structure in the underground wireless network topology, thereby generating the wireless network transmission result.

[0033] A highly stable wireless network transmission method for use in coal mining, wherein the method is based on the aforementioned highly stable wireless network transmission system for coal mining, and includes the following steps:

[0034] S1: Collect the power status and channel response records of the underground relay wireless transmission equipment, compare them with the upper limit of average power consumption and the threshold of the number of channel responses within a specified broadcast period, and construct a broadcast start identifier;

[0035] S2: Generate a corresponding broadcast control command based on the broadcast start identifier, activate the response process of the downhole adjacent communication device, sort the adjacent communication devices that respond to the broadcast control command, and obtain the recommended path for the device;

[0036] S3: Based on the recommended path of the device, select adjacent communication devices for data forwarding as relay communication devices, determine the consistency of the data trajectory of the signal strength of adjacent devices in the relay communication device sequence as a function of time, and generate a jump point path sequence;

[0037] S4: Establish an underground wireless communication link structure through the jump point path sequence, and instruct the relay communication device to collect communication status information to obtain the path communication status dataset;

[0038] S5: Based on the path communication status dataset and combined with all status information of the relay communication device during the transmission process, obtain the wireless network transmission result.

[0039] Compared with the prior art, the advantages and positive effects of the present invention are as follows:

[0040] In this invention, by collecting the power status and channel response records of underground equipment and constructing broadcast initiation conditions, communication broadcast triggering judgment can be made based on energy consumption and response effectiveness. Thus, path probing operations are initiated under the dual guarantee of acceptable power range and communication activity. The merits of responding equipment are evaluated based on signal strength, remaining power, and hop distance. Recommended paths are accurately selected using normalization and multi-parameter sorting algorithms, effectively achieving channel load balancing and inter-device collaborative communication. Furthermore, hop point device combinations are selected based on the consistency of signal change trends, enhancing path stability and time continuity. Then, by integrating hop point relationships and process parameters through inter-node communication response status, link structure mapping and result generation are achieved, thereby constructing a highly robust communication path that adapts to changes in the underground environment. This effectively reduces the communication failure rate under signal interference, improves the overall data integrity and link persistence during path forwarding, solves the signal attenuation problem caused by uneven distribution of underground communication equipment, complex interference, and enclosed structure, and enhances the adaptability of the underground wireless transmission system to dynamic environments and the response efficiency of real-time scheduling. Attached Figure Description

[0041] Figure 1 This is a system module diagram of the present invention;

[0042] Figure 2 This is a system framework diagram of the present invention;

[0043] Figure 3 This is a schematic diagram illustrating the principle of the broadcast determination module of the present invention;

[0044] Figure 4 This is a schematic diagram illustrating the principle of the path activation module of the present invention;

[0045] Figure 5 This is a schematic diagram illustrating the principle of the jump point filtering module of the present invention;

[0046] Figure 6 This is a schematic diagram illustrating the principle of the link construction module of the present invention;

[0047] Figure 7 This is a schematic diagram of the transmission output module of the present invention. Detailed Implementation

[0048] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0049] Please see Figure 1 This invention provides a technical solution: a highly stable wireless network transmission system for use in coal mining, comprising:

[0050] The broadcast determination module collects the power status and channel response records of the underground relay wireless transmission equipment, compares them with the upper limit of average power consumption and the threshold of the number of channel responses within a specified broadcast period, and constructs a broadcast start identifier.

[0051] The path activation module generates corresponding broadcast control commands based on the broadcast initiation identifier, activates the response process of downhole adjacent communication devices, sorts the adjacent communication devices that respond to the broadcast control commands, and obtains the recommended path for the devices.

[0052] The jump point filtering module filters adjacent communication devices used for data forwarding as relay communication devices based on the device recommended path, judges the consistency of the data trajectory of the signal strength of adjacent devices in the relay communication device sequence over time, and generates a jump point path sequence.

[0053] The link construction module establishes the underground wireless communication link structure through the jump point path sequence, and instructs the relay communication equipment to collect communication status information to obtain the path communication status dataset.

[0054] The transmission output module obtains the wireless network transmission result based on the path communication status dataset and all status information of the relay communication device during the transmission process.

[0055] The broadcast initiation identifier includes the trigger condition status, broadcast execution identifier, and path determination result; the broadcast control command includes the channel scheduling command, response activation information, and path detection flag; the device recommended path includes the response device list, path hop count sorting, and channel feedback set; the hop point path sequence includes the relay device sequence structure, signal trajectory continuity relationship, and path hop order information; and the wireless network transmission result includes the link topology, device status summary, and communication process data record.

[0056] Please see Figure 2 and Figure 3 The broadcast determination module includes:

[0057] The power identification submodule collects power status data of the downhole relay wireless transmission equipment, obtains the energy consumption data set of the same type of equipment in the current cycle in the working area, extracts the maximum value in the set as the upper limit of the average power consumption, and makes a numerical range judgment based on the upper limit and the collected power status to generate a power status comparison result.

[0058] First, the power status data of the underground relay wireless transmission equipment is collected. This process primarily involves real-time monitoring of the equipment's current operating voltage and current using power sensors installed on the equipment, generating a data sequence of voltage and current changes over time. For example, voltage and current values ​​are recorded every 10 minutes. Next, similar equipment is identified in the current work area and categorized using equipment identification codes. Power data for the same time period is extracted. Finally, the total power consumption for each equipment cycle is extracted and aggregated to form an energy consumption data set. During the aggregation process, the cycle power consumption of each equipment needs to be calculated using the formula: Energy = Voltage × Current × Time. For example, if a piece of equipment has a voltage of 12 volts and a current of 2 amps, the cycle power consumption is calculated as follows: Energy = Voltage × Current × Time. If the period is 10 minutes, the energy consumed is calculated as 12 multiplied by 2 and then multiplied by 10 minutes to convert it to the energy consumption per hour. Then, the energy consumption values ​​of all devices in the set are compared, and the maximum energy consumption value is selected as the upper limit of the average energy consumption. This upper limit is the maximum reference energy consumption value among similar devices in this period. Then, the current energy status value of the collected devices (e.g., the value obtained by multiplying voltage and current by running time) is compared with this maximum value. If the current energy of the device is lower than 50% to 70% of the maximum value, it is judged as a low energy status. If it is between 70% and 90%, it is a medium energy status. If it exceeds 90%, it is a high energy status. Based on the judgment result, the energy status comparison conclusion of the current device is output.

[0059] The channel recording submodule collects channel response records of underground relay wireless transmission equipment within a specified broadcast period, extracts the number of channel responses in each period and compares them with a set response count threshold to filter valid channel response records.

[0060] First, channel response records are collected for the underground relay wireless transmission equipment within a specified broadcast period. The broadcast period is generally set to 5 minutes. The equipment sends a broadcast signal at the beginning of the period, and other devices receive it and send response signals at fixed time intervals. The system records the timestamps of the received responses and forms a response log. The log record structure includes fields such as the sending device ID, receiving device ID, response time, and response signal strength. Then, the number of valid channel responses in each broadcast period is extracted. The judgment criterion is that the received signal strength in the same broadcast period is higher than a certain reference strength value (such as -80dBm) and the time interval does not exceed the set value (such as 1 second). After counting the number of valid responses, it is compared with a pre-set response count threshold. This threshold can be obtained through previous experimental testing. For example, 10 times is set as the threshold. That is, if the number of responses in a certain period is 12, it is a valid period. If it is less than 10, it is an invalid period. The valid record filtering logic is: the period with more than or equal to 10 responses in each period is included in the valid response record, and the others are discarded, forming a filtered valid channel response record dataset.

[0061] The threshold comparison submodule determines whether the two data points simultaneously reach the set standards of the average power consumption limit and the channel response count threshold based on the power status comparison result and the valid channel response record. If both conditions are met, a broadcast start flag is generated.

[0062] First, the status is determined based on the power status comparison results. The power value is extracted and compared with the maximum power consumption limit to determine whether the current range has reached the upper limit standard. For example, if the maximum power consumption is 24 watt-hours and the current device power is 22 watt-hours, the power is in a high range and can be marked as reaching the power limit standard. Then, the valid channel response records in the current period are obtained. If the number of valid responses in the record period is 12 and the response threshold is 10, it means that the channel response set threshold standard has been reached. The judgment logic is: the current period simultaneously meets the conditions that the power status is high and the number of channel response records is higher than or equal to the set threshold. After these two conditions are met, the system is triggered to generate a broadcast start flag. The broadcast start flag is a binary flag bit "1" or "0" output by the system. In this example, both conditions are met, so the broadcast flag output is "1". This output signal will be sent to the upper-level broadcast control module for further broadcast triggering.

[0063] Please see Figure 2 and Figure 4 The path activation module includes:

[0064] The instruction generation submodule, based on the broadcast start flag, determines that the state is broadcastable. Then, the current downhole relay wireless transmission device issues an instruction to construct broadcast control information and sets control parameters to trigger the path detection process, thereby generating broadcast control instructions.

[0065] From the moment the downhole relay wireless transmission device receives the broadcast start flag, if it determines that the flag indicates a broadcastable state, it enters the instruction generation process. The device first extracts basic network parameters such as its own work area number, device unique identifier, and current system time. These parameters serve as the data foundation for constructing broadcast control information. Then, the device sets control parameters based on the communication environment characteristics of the work area, including the target distance for path detection, the maximum number of jumps, the minimum threshold value of the received signal strength, and the response waiting time. The specific values ​​of these parameters are usually derived from the statistical analysis of historical communication records in this well section and the calculation of conventional distances between devices. For example, if there are many communication obstacles in the area, it is necessary to appropriately increase the allowed number of jumps and extend the response time to ensure that the communication equipment can respond effectively. The device combines the above basic parameters and control parameters and encapsulates them into broadcast control information through a preset structure format. This information indicates the path detection task, parameter settings, and expected behavior of the receiving device. Finally, the device sends the control information through its wireless communication module, generates the corresponding broadcast control command, and completes the instruction broadcasting process.

[0066] The device response submodule, based on broadcast control commands, activates the downhole adjacent communication devices within the current device communication range to execute the response process, and collects three parameters returned by the device during the response process: received signal strength, power status, and predicted jump distance, to generate a path evaluation parameter set;

[0067] After the broadcast control command reaches the communication range, all adjacent downhole communication devices within the current device's wireless coverage area initiate a response process. Each adjacent device first determines the validity of the control command and its compatibility with its own status. Upon confirmation, it activates the signal strength detection module to measure the power level of the received signal. This measurement process involves the electrical signal received by the antenna being amplified and detected by the output circuit, and then the signal strength value is obtained through amplitude conversion. Simultaneously, the power sensor within the device begins collecting current voltage and current data. The power value is calculated using the formula "Power = The calculation is performed by multiplying the voltage by the current by the running time. For example, if the voltage is 12 volts, the current is 1 amp, and the running time is 10 minutes, the time needs to be converted to hours before multiplication to obtain the remaining power of the device. Then, combined with the signal jump history and actual distance change data recorded in the device's records, the predicted jump distance is estimated. This distance is usually calculated and accumulated by combining the communication delay difference between devices with the propagation speed of sound waves or electromagnetic waves. The three collected results, namely the received signal strength, power status, and predicted jump distance, are integrated into a path evaluation parameter set. The device will return this parameter set to the broadcast source device within a preset feedback window period.

[0068] The path ranking submodule, based on the path evaluation parameter set, performs normalization processing on the three parameters respectively, and ranks the paths corresponding to each downhole adjacent communication device according to the preset evaluation criteria using the TOPSIS ranking algorithm, and selects the recommended path for the device based on the ranking results;

[0069] The path ranking submodule performs a multi-index comprehensive ranking based on the path evaluation parameter set returned by adjacent downhole communication devices to select the optimal broadcast path device. This process uses the TOPSIS method, based on three key evaluation indicators: received signal strength, power status, and predicted hop distance. The dimensions of these indicators are first standardized, and then vector distance and relative proximity are calculated.

[0070] The three evaluation indicators are as follows:

[0071] Received signal strength, denoted as , is a positive indicator, representing the strength of the broadcast signal received by the device, measured in decibels and milliwatts (dBm).

[0072] Battery status, denoted as This is a positive indicator, representing the device's current remaining power, measured in watt-hours (Wh). This value is directly measured by the device.

[0073] Predicted jump distance, denoted as , is a negative indicator, with the unit being meters (m), representing the physical distance between the device and the relay broadcasting equipment; the shorter the distance, the better.

[0074] The normalization formula is as follows:

[0075] For positive indicators (i.e.) , ): ,in ;

[0076] For negative indicators: ;

[0077] in, : Indicates the current device to be evaluated is in the _th ... The original values ​​of each indicator; : indicates that the device is in the Normalized values ​​for the indicators; : indicates the first The device in the The original values ​​of the indicators; : The sum of the squares of the original values ​​of all equipment under this indicator; : Represents the square and square root used in normalization, serving to standardize the scale; : Indicates the total number of adjacent communication devices underground; : Indicates the "received signal strength" indicator; : Indicates the "battery status" indicator; : The original value of the jump distance of the device to be evaluated; : The normalized value of the jump distance of this device. The smaller the jump distance, the better. The larger; : No. Original jump distance values ​​for each device; The minimum jump distance among all devices; The maximum jump distance among all devices; : The squared value of the reverse distance for each device; : The sum of the squares of the reverse jump distances of all devices; The total number of adjacent devices participating in the assessment.

[0078] After the normalized matrix is ​​constructed, two types of ideal reference vectors need to be constructed for distance calculation:

[0079] Ideal solution The combination of the maximum normalized values ​​of the three indicators represents the optimal combination of equipment paths. ;

[0080] Negative ideal solution The combination of the minimum normalized values ​​of the three indicators represents the worst-case path combination. ;

[0081] in, All equipment in the The maximum value in the normalized index represents the optimal performance; All equipment in the The minimum value among the normalized metrics represents the worst performance; The ideal solution is the set of all normalized indices that have reached their maximum values, representing the optimal equipment. The negative ideal solution is the set of all normalized indices that take the minimum value, representing the worst-case device; These correspond to received signal strength, battery status, and jump distance, respectively. : Represents the normalized value of the signal strength received by the current device. After normalization, it is a dimensionless value. The larger the value, the stronger the relative signal. : This represents the normalized value of the current device's battery status. It is a dimensionless value, and the larger the value, the more sufficient the battery power. : This represents the normalized value of the predicted jump distance of the current device. It is a dimensionless value. The larger the value, the shorter the distance between the device and the broadcast source (because this is a negative indicator, the normalization method has been adjusted in the opposite direction).

[0082] For each device, calculate the Euclidean distance between its normalized parameter vector and the ideal solution and the negative ideal solution:

[0083] Distance from the ideal solution: ;

[0084] Distance from the negative ideal solution: ;

[0085] in, The distance from the current device to the ideal solution; : The distance from the current device to the negative ideal solution; The current device is in the... The normalized value of the indicator; : No. Ideal solution reference value for each indicator; : No. The negative ideal solution reference value for each index; the squared differences are summed, and the square root is taken to measure the relative distance between the device and the reference solution. These correspond to received signal strength, battery status, and jump distance, respectively. The maximum value among the normalized received signal strengths of all devices, that is, the strongest signal strength of the device under ideal conditions. The maximum value among all devices' normalized power states, i.e., the device's most sufficient power value under ideal conditions. The maximum value among all normalized jump distances of all devices, that is, the normalized value corresponding to the shortest jump distance of a device under ideal conditions (due to reverse processing, the maximum value represents the best). The minimum normalized received signal strength among all devices, i.e., the normalized value of the device with the weakest signal. The minimum value among all devices' normalized power status, i.e., the normalized value of the device with the least remaining power. The minimum value among all normalized jump distances of all devices, that is, the normalized result of the device with the longest jump distance (the smallest value after normalization represents the worst path).

[0086] Based on the two types of distances mentioned above, calculate the relative proximity of each device. The score for the quality of the device path is as follows: ;

[0087] in, : This represents the path ranking score, ranging from 0 to 1; a larger value indicates a better path for that device; all devices are ranked according to... Sort by value from largest to smallest, and the device with the largest value is recommended as the priority broadcast path device.

[0088] This method comprehensively considers the three factors of signal, energy and switching cost of downhole communication equipment, ensuring that path selection takes into account stability, sustainability and efficiency.

[0089] Suppose there are three adjacent devices The original values ​​of its three indicators are as follows:

[0090] Received signal strength (unit: dBm): ;

[0091] Remaining battery power (unit: Wh): ;

[0092] Jump distance (unit: m): .

[0093] Received signal strength (Positive indicator):

[0094] Denominator = ;

[0095] ;

[0096] Remaining battery power (Positive indicator):

[0097] Denominator = ;

[0098] ;

[0099] Jump distance (Negative indicator):

[0100] First, calculate the intermediate quantities: ;

[0101] Calculate the inverted value: The converted value is: , The converted value is: , The converted value is: ;

[0102] Normalized denominator: denominator = ;

[0103] Normalization results: .

[0104] Constructing the ideal solution and the negative ideal solution:

[0105] Ideal solution ;

[0106] Negative ideal solution .

[0107] Calculate the distance to each device:

[0108] equipment :

[0109] ;

[0110] ;

[0111] equipment :

[0112] ;

[0113] ;

[0114] equipment :

[0115] ;

[0116] .

[0117] Calculate relative proximity :

[0118] .

[0119] Sort results (by) (from largest to smallest) : →First recommended path device, : →Second preferred path, : → This path is not recommended.

[0120] The demonstration showed the entire process of how downhole relay equipment uses the TOPSIS method to comprehensively consider three factors—signal strength, power status, and jump distance—to progressively calculate, score, rank, and determine the optimal communication path equipment.

[0121] First, normalization transforms evaluation indicators with different dimensions to a unified numerical scale, allowing signal strength, power status, and jump distance to participate in the calculation within the same evaluation system. Signal strength and power status are positive indicators, with higher values ​​representing better performance. Jump distance, a negative indicator, undergoes inverse transformation, resulting in a higher normalized value for shorter distances. After normalization, the system constructs an ideal solution representing the optimal path and a negative ideal solution representing the worst path, each composed of the best and worst normalized values ​​for each indicator across all devices. Then, the distances between each device and the ideal solution, as well as the negative ideal solution, are calculated to assess its position in the overall path evaluation. A relative proximity score is obtained by dividing the distance of each device from the negative ideal solution by the sum of its distances to both the ideal and negative ideal solutions; a score closer to one indicates that the path is closer to the ideal standard. The core significance of this calculation process is to quantitatively identify the downhole communication device with the most comprehensive advantages in terms of strong signal, sufficient power, and low jump cost among multiple path options.

[0122] Please see Figure 2 and Figure 5 The jump point filtering module includes:

[0123] The candidate construction submodule filters downhole adjacent communication devices with data forwarding capabilities according to the order of the recommended paths of the devices, and generates a candidate relay sequence;

[0124] After completing the path sorting and obtaining the priority scores of all downhole adjacent communication devices, the devices are ranked from highest to lowest score. The system then assesses the forwarding capability of the top-ranked devices one by one, based on two criteria: first, whether the device is currently online; and second, whether the remaining power meets the minimum forwarding power consumption requirement. For example, the minimum power consumption requirement can be set to more than twice the path hop power consumption. If a device's current power status value is greater than this threshold, it is determined to have data forwarding capability. The power consumption reference value involved in the assessment is the sum of the signal transmission and reception power in the path. The system calculates the energy consumption required for a single hop using the formula "Power Consumption Requirement = Transmit Power + Receive Power", and then compares the device's current power value with the power consumption requirement. If the requirement is met, the device is retained; otherwise, it is skipped and enters the next device evaluation process, thus selecting a group of devices that meet the forwarding conditions to form a candidate relay sequence.

[0125] The trajectory extraction submodule collects a continuous data sequence of the received signal strength between each adjacent device in the candidate relay sequence as a function of time, and generates a set of signal change trajectories.

[0126] The system selects all adjacent device combinations from the candidate relay sequence and collects communication data between each pair of devices, mainly recording the changes in received signal strength over a continuous time period. This recording process is completed by sampling once per unit time using the wireless channel measurement function. The signal strength changes over time are arranged sequentially to form a continuous data sequence, i.e., constructing a "signal trajectory". Each trajectory contains the signal fluctuations within a fixed time period. For example, the received signal strength is recorded every ten seconds and sorted in chronological order to form a time series. In trajectory extraction, time alignment must be ensured, i.e., the sampling time points of all adjacent devices are consistent to avoid errors caused by time offset. The system records the signal trajectory between each pair of adjacent devices as an independent sequence, forming a "signal change trajectory set". This trajectory set is the basic input for subsequent similarity comparison and jump point screening. Each record represents the communication signal status of a specific device pair within a specific time period.

[0127] The consistency judgment submodule inputs the continuous data sequence of the received signal strength of each pair of adjacent devices in the signal change trajectory set as a function of time into the longest common subsequence algorithm, compares the structural similarity between adjacent trajectories, filters the device combinations with consistent change trends, and generates the jump point path sequence.

[0128] This module selects downhole communication equipment combinations that exhibit consistent and stable behavior during signal transmission. Based on the signal strength variation trajectories between adjacent devices, it uses an improved Longest Common Subsequence (LCS) algorithm to measure structural similarity, outputting a sequence of jump point paths with consistent signal change trends. This module combines continuous time-series samples to construct trend and intensity scores, and then uses weighted fusion to derive a similarity score.

[0129] Suppose that for a pair of adjacent underground communication devices, the signal trajectories obtained by continuous sampling within a certain time window are as follows: sequence : Represents the change in received signal strength of the first device from time point 1 to T; sequence ; indicates the signal strength change of the second adjacent device within the same time period; where, : Represents the signal strength value of the first device at the t-th sampling time point, in decibels and milliwatts (dBm); : Represents the signal strength value of the second device at the t-th sampling time point.

[0130] The overall similarity S of the signal trajectories between two devices is defined as follows:

[0131] ;

[0132] in, Signal strength approximation function , : The signal strength of the first device at time point t; The signal strength of the second device at time t; The amplitude of the signal difference between the two devices at this point in time; : Maximum permissible signal strength difference, used to normalize the degree of difference, usually set by historical data, for example, 50dBm; The closer the value is to 1, the closer the signal strength of the two devices is at that point in time. Signal trend consistency function , The first device at the previous time point The signal strength; The second device was at the previous time point. The signal strength; The amplitude of signal change of the first device at two adjacent time points; The signal change amplitude of the second device within the same time span; if the signals of the two devices change in the same direction (i.e. both rising or both falling), their product is positive, then the trend is consistent, and the output is 1; if the directions are different (e.g. one rising and one falling), their product is negative, then the trend is inconsistent, and the output is 0. It measures the "directional synchronicity" of signal changes rather than the absolute value. : Represents the weight of signal strength proximity; : Represents the weight of the consistency of the signal's changing trend; both satisfy the following constraints: The value ranges from 0 to 1; when the underground communication environment is subject to significant interference and signal strength fluctuations are severe, the trend is more stable than the strength, and a larger value should be set in this case. ,For example , When the channel is stable but the distance is uneven or the equipment layout changes, the signal strength is more reliable and should be set to a higher value. ,For example , The weights can also be set by dynamically analyzing the standard deviation and rate of change of the slope of the signal. : Indicates the total number of sampling time points used for comparison; all signal strength samples are collected at fixed intervals to ensure and Corresponding to the same physical time

[0133] In a certain underground area, relay device M1 and its adjacent device M2 collected signal strength data at 5 consecutive time points, in dBm. The results are as follows: Signal trajectory of device M1 (sequence A): , Device M2 signal trajectory (sequence B): .

[0134] The maximum allowable signal difference is set as follows: (dBm); Total number of time points T=5; Intensity weight Trend weight This indicates a greater emphasis on trend consistency. Because the trend function requires... Therefore, the calculation starts from... arrive There are a total of 4 time periods.

[0135] Second time point Difference: Intensity function: Direction of change: The product is 6 > 0. Weighted values: .

[0136] The third time point Difference: Direction of change: The product is 8 > 0. Weighted values: .

[0137] 4th time point Difference: Direction of change: The product is 6 > 0. Weighted values: .

[0138] 5th time point Difference: Direction of change: The product is 4 > 0. Weighted values: .

[0139] Sum the weighted scores for each moment, then divide by the number of segments:

[0140] ;

[0141] Similarity score The value is much higher than the set threshold of 0.75; it is determined that the signal change trajectories between the two devices are highly consistent; the combination of devices will be included in the jump point path sequence as a stable link connection.

[0142] The first formula calculates the similarity of signal strength between two devices at each time point; a higher value indicates greater similarity in the signals received by the two devices at the same time point. The second formula determines whether the signal change trends of the two devices are consistent between adjacent time points, i.e., whether they are simultaneously strengthening or weakening their signals. Only when the direction of change is the same are they considered to have consistent trends. These two results are multiplied by a set weighting coefficient, reflecting the emphasis on strength differences or trend synchronization in different scenarios. Then, the weighted results at all time points are summed and averaged to obtain an overall similarity score, which measures the consistency of the signal behavior of the two devices throughout the time series. A value close to one indicates high consistency, while a value close to zero indicates significant difference. The entire calculation process begins with collecting continuous signal data from the two devices, calculating the strength difference and direction of change point by point, obtaining an overall score through weighted fusion, and finally filtering out device combinations with consistent performance based on a set threshold. This is used to construct a jump point path sequence, enabling automatic identification and filtering of stable communication links.

[0143] Please see Figure 2 and Figure 6 The link building module includes:

[0144] The path establishment submodule establishes the underground wireless communication link structure from the broadcasting device to the receiving device terminal according to the jump point arrangement order of the jump point path sequence, and generates the communication link structure.

[0145] After obtaining the hop path sequence, the wireless communication link between the broadcast initiating device and the receiving device is constructed sequentially according to the order of each hop. The establishment process extracts the first node from the path sequence as the starting broadcast device, and connects each hop device in turn until the final node forms a complete path. During processing, the system confirms the communication capability between adjacent hops, including whether the two devices are within effective signal coverage and whether they have available communication channels. Under the premise that all hop conditions are met, all hop information, hop order, path length, average hop distance, and other parameters of the entire path are integrated into a communication link structure. The path length can be calculated by multiplying the number of hops by the average hop distance; for example, path length = number of hops multiplied by average hop distance. The output structure will serve as a reference template for subsequent task command issuance and status acquisition.

[0146] The instruction issuing submodule sends communication status acquisition instructions to all relay communication devices according to the node order in the communication link structure, configures the acquisition task items and specifies the execution order, and generates a status acquisition task set.

[0147] After the communication link structure is established, the order of each node is read. Starting from the initial broadcast device, status acquisition task commands are sent to the relay communication devices one by one according to the hop order recorded in the structure. Each command contains information such as device number, acquisition time, acquisition parameter type, and parameter sampling interval. The task is issued in a sequential trigger mode, that is, the next hop task is issued to the next device only after the previous device confirms receipt. Acquisition task items include transmission time, response time, and bit error rate, etc. Each task item is embedded in a unified format command packet and wirelessly transmitted by the communication module. The system will confirm the response status of each device. Unresponsive devices will retransmit once after a specified time window. All tasks are combined to form a complete status acquisition task set for path communication process performance analysis.

[0148] The status acquisition submodule integrates the data collected by each relay communication device in the status acquisition task set, including its own transmission time, response delay fluctuation, signal holding time, and data error rate during the communication process, and generates a path communication status dataset.

[0149] Upon receiving the instruction, each relay communication device initiates its internal data acquisition program to monitor its position in the communication link. The acquisition tasks include: the time taken for the device to complete data transmission (transmission time); the waiting fluctuation before the receiver confirms receipt (response delay fluctuation); the period during which the signal can be stably maintained during continuous communication (signal holding time); and the error rate during data transmission (bit error rate). Each parameter is obtained through the device's local recording module and signal analysis module. For example, bit error rate can be determined by comparing the difference in the number of bits between the transmitted data and the received confirmation data, using the formula: Bit error rate = Number of error bits divided by the total number of bits. Response delay fluctuation can be calculated by subtracting the transmission time from the reception time and then calculating the difference range multiple times, for example: Response delay fluctuation = Maximum response time minus Minimum response time. Signal holding time is the duration for which the continuous signal strength is greater than the minimum reception threshold. Transmission time is the total time required from the start of transmission to completion. The data collected from all devices is integrated to form a path communication status dataset.

[0150] Please see Figure 2 and Figure 7 The transmission output module includes:

[0151] The jump point combination submodule extracts the jump point sequence relationship and corresponding status of each relay communication device in the path communication status dataset, associates and combines the transmission response information between device jump points, and generates a jump point combination structure set.

[0152] After obtaining the path communication status dataset, the system begins extracting the hop order relationship of each relay communication device. During extraction, the system reads the position index value of each device in the link from the structure to reconstruct the hop order. Subsequently, the system further extracts parameters such as transmission time and response delay fluctuations for each device from the status data, comparing the transmission and response information between adjacent devices one by one and associating them. For example, it pairs the transmission time of the first device with the response time of the second device, subtracting the transmission time from the response time to obtain the propagation time between hops. The propagation time is calculated as: propagation time = response time - transmission time. If the difference is within an acceptable range, it is marked as a valid hop pair. After traversing the entire path, the system combines all hop pairs and their corresponding status parameters to form a hop pair structure set. Each pair contains structured content such as the hop start and end device numbers, transmission and response information, and error rate.

[0153] The structure assembly submodule calls the jump point combination structure set to map the jump point sequence and state parameter combination to the underground wireless network topology and builds the transmission structure model.

[0154] Using a set of hop point combinations as the input data source, and combining it with existing topology information in the underground wireless network, the system maps and assembles the hop point structure. First, the system identifies the relative position of each hop point pair within the topology and verifies the legality of its connection, such as confirming that its physical distance is within signal coverage and that there are no breaks in the hop link. After confirming the connection relationship is correct, the hop points are sequentially mapped to connecting segments between topology nodes, and state parameters are attached to the connection as edge weight attributes. For example, the bit error rate of a hop segment can be used as an edge stability indicator, while the signal hold time can be used as a basis for evaluating link persistence. If multiple hop segments constitute a continuous path, the system automatically assembles them sequentially into a transmission structure model. This model uses network nodes and hop segment attributes as basic units, including state association information and communication performance characteristics between nodes.

[0155] The result generation submodule calls the transmission structure model to organize and summarize the hop sequence and parameter structure in the path, and outputs the content of the valid path segment based on the status structure of the connected hops in the underground wireless network topology, thus generating the wireless network transmission result.

[0156] The system retrieves all hop sequence information and their associated state parameters from the assembled transmission structure model, and logically organizes and summarizes the entire path. During the organization process, the system categorizes all hop information according to device number order, extracts each valid path segment between the starting hop and the terminal hop, and summarizes parameters such as transmission time, response delay fluctuation, signal holding time, and bit error rate for each edge in the path segment. For example, path segment stability can be calculated using the average bit error rate (BER): average BER = sum of all hop segment BERs divided by the number of hop segments; link latency can be calculated by subtracting the first transmission time from the total response time of the path segment; link persistence is determined by using the shortest signal holding time as the lower limit of link stability. Finally, the system marks all selected valid path segments as usable paths and outputs their communication characteristic structure to form wireless network transmission result data, which is used to guide link maintenance and optimization adjustments.

[0157] A highly stable wireless network transmission method for coal mining, based on the aforementioned highly stable wireless network transmission system for coal mining, includes the following steps:

[0158] S1: Collect the power status and channel response records of the underground relay wireless transmission equipment, compare them with the upper limit of average power consumption and the threshold of the number of channel responses within a specified broadcast period, and construct a broadcast start identifier;

[0159] S2: Generate corresponding broadcast control commands based on the broadcast start flag, activate the response process of downhole adjacent communication devices, sort the adjacent communication devices that respond to the broadcast control commands, and obtain the recommended path for the devices;

[0160] S3: Based on the device recommended path, select adjacent communication devices for data forwarding as relay communication devices, determine the consistency of the data trajectory of the signal strength of adjacent devices in the relay communication device sequence over time, and generate a jump point path sequence;

[0161] S4: Establish the underground wireless communication link structure through the jump point path sequence, and instruct the relay communication equipment to collect communication status information to obtain the path communication status dataset;

[0162] S5: Based on the path communication status dataset and combined with all status information of the relay communication device during the transmission process, obtain the wireless network transmission result.

[0163] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention in any other way. Any person skilled in the art may make changes or modifications to the above-disclosed technical content to create equivalent embodiments that can be applied to other fields. However, any simple modifications, equivalent changes, and modifications made to the above embodiments based on the technical essence of the present invention without departing from the scope of the present invention shall still fall within the protection scope of the present invention.

Claims

1. A high-stability wireless network transmission system applied to coal mining of a mine, characterized in that, The system comprises: A broadcast determination module collects the power state and channel response record of the downhole relay wireless transmission device, compares the power average energy consumption upper limit and the channel response number threshold in the specified broadcast period, and constructs a broadcast start identifier; A path activation module generates a corresponding broadcast control instruction according to the broadcast start identifier, activates the downhole adjacent communication device response flow, sorts the adjacent communication devices responding to the broadcast control instruction, and obtains a device recommended path; A hop screening module screens the adjacent communication devices for data forwarding as relay communication devices according to the device recommended path, judges the data trajectory consistency of the signal strength of adjacent devices in the relay communication device sequence with time, and generates a hop path sequence; The hop screening module comprises: A candidate construction submodule screens downhole adjacent communication devices with data forwarding capability according to the arrangement order of the device recommended path, and generates a candidate relay sequence; A trajectory extraction submodule collects the continuous data sequence of the received signal strength of each adjacent device in the candidate relay sequence with time, and generates a signal change trajectory set; An consistency judgment submodule inputs the continuous data sequence of the received signal strength of each pair of adjacent devices in the signal change trajectory set with time into a longest common subsequence algorithm, compares the structural similarity between adjacent trajectories, screens device combinations with consistent change trends, and generates a hop path sequence; wherein the structural similarity between adjacent trajectories is compared using the formula: ； in, It is a signal strength approximation function. It was the first device at that point in time. signal strength, The second device at that time point signal strength, It is a signal trend consistency function. The first device at the previous point in time signal strength, The second device was at the previous point in time. signal strength, It represents the weight for the proximity of signal strength. It represents the weight of the consistency of the signal's changing trend. This indicates the total number of sampling time points used for comparison; A link construction module establishes a downhole wireless communication link structure through the hop path sequence, instructs the relay communication device to collect communication state information, and obtains a path communication state data set; A transmission output module obtains a wireless network transmission result according to the path communication state data set and in combination with all state information of the relay communication device in the transmission process.

2. The high-stability wireless network transmission system applied to coal mining of claim 1, characterized in that: The broadcast start identifier includes trigger condition state, broadcast execution identifier, and path determination result, the broadcast control instruction includes channel scheduling command, response activation information, and path detection flag, the device recommended path includes response device list, path hop number order, and channel feedback set, the hop path sequence includes relay device sequence structure, signal trajectory continuity relationship, and path jump order information, and the wireless network transmission result includes link topology structure, device state summary, and communication process data record.

3. The high-stability wireless network transmission system applied to coal mining of claim 1, characterized in that: The broadcast determination module comprises: A power recognition submodule collects the power state data of the downhole relay wireless transmission device, obtains the energy consumption data set of the same type device in the current period in the working area, extracts the maximum value in the set as the power average energy consumption upper limit, performs numerical interval judgment according to the upper limit and the collected power state, and generates a power state comparison result; A channel record submodule collects the channel response record of the downhole relay wireless transmission device in the specified broadcast period, extracts the channel response number in each period from the channel response record, compares the extracted channel response number with the set response number threshold, and screens the channel response effective record; The threshold comparison submodule judges whether the two data reach the set standards of the upper limit of the average energy consumption and the threshold of the channel response times simultaneously according to the comparison result of the power state and the valid record of the channel response, and generates a broadcast start identifier if both conditions are met.

4. The high-stability wireless network transmission system applied to coal mining of claim 1, characterized in that: The path activation module comprises: An instruction generation submodule generates a broadcast control instruction by issuing an instruction from the current downhole relay wireless transmission device to build broadcast control information and setting a control parameter for triggering a path detection process based on the broadcast start identifier after judging that it is in a broadcastable state. A device response submodule activates downhole adjacent communication devices within the current device communication range to execute a response process based on the broadcast control instruction, collects three parameters of received signal strength, power state and predicted jump distance returned by the devices in the response process, and generates a path evaluation parameter set. A path sorting submodule sorts the three parameters respectively by normalizing them based on the path evaluation parameter set, sorts the path corresponding to each downhole adjacent communication device according to a preset evaluation standard through a TOPSIS sorting algorithm, and selects a device recommended path according to the sorting result.

5. The high-stability wireless network transmission system applied to coal mining of claim 4, characterized in that: The path evaluation parameter set is sorted according to the path corresponding to each downhole adjacent communication device, and the formula is as follows: ； ； calculating the Euclidean distance between each device normalized parameter vector and the ideal solution and the Euclidean distance between the ideal solution and the negative ideal solution ; wherein, represents a normalized value of a current device received signal strength, represents a normalized value of a current device battery status, represents a normalized value of a current device predicted hop distance, is a maximum value of all device normalized received signal strengths, is a maximum value of all device normalized battery statuses, is a maximum value of all device normalized hop distances, is a minimum value of all device normalized received signal strengths, is a minimum value of all device normalized battery statuses, is a minimum value of all device normalized hop distances. According to the Euclidean distance between each device normalized parameter vector and the ideal solution and the Euclidean distance between the positive and negative ideal solutions using the formula: ； calculating a path score for each downhole abutment communication device .

6. The high-stability wireless network transmission system for use in coal mining according to claim 1, characterized in that: The link construction module comprises: A path establishment submodule establishes a downhole wireless communication link structure from the broadcast device start to the receiving device terminal according to the hop arrangement order of the hop point path sequence, and generates a communication link structure body. An instruction issuing submodule sends a communication state collection instruction to all relay communication devices according to the node order in the communication link structure body, configures a collection task item and specifies an execution order, and generates a state collection task set. A state collection submodule integrates the transmission time, response delay fluctuation, signal holding time and data error code of each relay communication device in the state collection task set, and generates a path communication state data set.

7. The high-stability wireless network transmission system for use in coal mining according to claim 1, characterized in that: The transmission output module comprises: A hop point combination submodule extracts the hop point order relationship and corresponding state of each relay communication device in the path communication state data set, associates and combines the transmission response information between device hops, and generates a hop point combination structure set. A structure assembly submodule calls the hop point combination structure set, maps the hop point order and state parameters to the downhole wireless network topology structure, and constructs a transmission structure model. A result generation submodule calls the transmission structure model, sorts and summarizes the hop point sequence and parameter structure in the path, and outputs the valid path segment content according to the connected hop point state structure in the downhole wireless network topology structure, and generates a wireless network transmission result.

8. A high-stability wireless network transmission method applied to coal mining of a mine, characterized in that, The application of the high-stability wireless network transmission system for coal mining according to any one of claims 1-7 comprises the following steps: S1: Collect the power state and channel response record of the downhole relay wireless transmission device, compare with the upper limit of the average energy consumption and the threshold of the channel response times in the specified broadcast period, build a broadcast start identifier; S2: generating a corresponding broadcast control instruction according to the broadcast start identifier, activating a downhole adjacent communication device response process, and sorting adjacent communication devices responding to the broadcast control instruction to obtain a device recommended path; S3: screening adjacent communication devices for data forwarding as relay communication devices according to the device recommended path, judging the consistency of data trajectories of signal strength changes with time of adjacent devices in the relay communication device sequence, and generating a hop point path sequence; arranging downhole adjacent communication devices with data forwarding capability according to the device recommended path to generate a candidate relay sequence; collecting continuous data sequences of signal strength changes with time between each adjacent device in the candidate relay sequence to generate a signal change trajectory set; inputting continuous data sequences of signal strength changes with time of each pair of adjacent devices in the signal change trajectory set into a longest common subsequence algorithm, comparing the structural similarity between adjacent trajectories, screening device combinations with consistent change trends, and generating a hop point path sequence; wherein the structural similarity between adjacent trajectories is compared using the formula: ； in, It is a signal strength approximation function. It was the first device at that point in time. signal strength, The second device at that time point signal strength, It is a signal trend consistency function. The first device at the previous point in time signal strength, The second device was at the previous point in time. signal strength, It represents the weight for the proximity of signal strength. It represents the weight of the consistency of the signal's changing trend. This indicates the total number of sampling time points used for comparison; S4: establishing a downhole wireless communication link structure through the hop point path sequence, instructing relay communication devices to collect communication state information, and obtaining a path communication state data set; S5: obtaining a wireless network transmission result according to the path communication state data set and combining all state information of the relay communication devices in the transmission process.

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