A method for testing communication quality of medium coverage nodes and a method for establishing communication links

Abstract

The present invention discloses a method for testing the communication quality of a dielectric-covered node and a method for establishing a communication link, comprising the following steps: S1, model establishment; S2, parameter adjustment, using a fixed single variable to adjust the model parameters, the model parameters including the dielectric coverage thickness of the dielectric model and the spacing between the transmitting node model and the receiving node model; S3, running a simulation, recording the communication results, and analyzing and judging whether the communication status of the environmental monitoring node is good; S4, based on the communication results of S3, re-adjusting the parameters, repeating steps S2 and S3 in sequence, testing multiple times, and obtaining a set of dielectric coverage thickness values ​​corresponding to the node spacing range of the node model that meets the communication conditions, as well as a set of node spacing values ​​corresponding to the dielectric coverage thickness range. The present invention is directed to testing point-to-point communication performance in coal-rock covered media, and improves the efficiency of reestablishing communication links between nodes.

Description

Technical Field

[0001] The present invention relates to the field of wireless communication technology, and more particularly to a method for testing the communication quality of a medium coverage node and a method for establishing a communication link. Background Art

[0002] Disasters such as underground coal mine gas explosions can destroy pre-deployed wireless sensor monitoring networks, severely impacting environmental monitoring nodes. Some environmental monitoring nodes may cease functioning due to structural damage or component damage. Others, while less severely affected, may be covered by coal, rock, or other media. In these situations, node communication becomes a challenge. Furthermore, post-disaster network reconstruction can be difficult to detect. This hinders node discovery, the first step in network reconstruction.

[0003] Therefore, understanding the survival of environmental monitoring nodes after a disaster and the communication between surviving nodes is crucial. Conducting field experiments at a real-world site would be both labor-intensive and resource-intensive, resulting in significant waste of experimental materials. Furthermore, surface experiments cannot accurately replicate the conditions of a mine disaster. Therefore, conducting research using simulation is a relatively ideal approach.

[0004] Currently, there is no communication simulation for nodes in coal and rock overburden. Therefore, this paper proposes a simulation method based on network simulation software to determine the relationship between coal and rock overburden thickness and node communication distance. This method aims to provide a basis for node discovery during post-disaster network reconstruction and provide information support for emergency rescue. Summary of the Invention

[0005] The purpose of the present invention is to disclose a method for testing the communication quality of medium-covered nodes and a method for establishing a communication link. By constructing a post-disaster node simulation framework and adjusting parameters, the relationship between coal and rock coverage thickness, node spacing and communication conditions is obtained, and a simulation method is constructed to reduce the waste of resources and the inconvenience of ground experiments, provide data support for the reconstruction of communication links between ground nodes, and improve reconstruction efficiency.

[0006] To achieve the above object, the present invention provides a method for testing the communication quality of a medium coverage node, comprising the following steps:

[0007] S1, model establishment, select the medium type covered by the environmental monitoring node and the communication method between the environmental monitoring node, preliminarily select the medium coverage thickness value of the environmental monitoring node, and build a network model based on network simulation software for communication testing of the environmental monitoring node;

[0008] S2, parameter adjustment, uses a fixed single variable method to adjust the model parameters, including the medium coverage thickness of the medium model and the distance between the sending node model and the receiving node model;

[0009] S3, run the simulation, record the communication results, and analyze and judge whether the communication status of the environmental monitoring node is good based on the communication results under a single simulation;

[0010] S4, based on the communication results of S3, readjust the parameters, repeat steps S2 and S3 in sequence, and test multiple times to obtain the set of medium coverage thickness values ​​corresponding to the node spacing range of the node model that meets the communication conditions and the set of node spacing values ​​corresponding to the medium coverage thickness range.

[0011] As a further improvement of the present invention, the network model includes:

[0012] The sending node model has a sensor for environmental monitoring and is capable of sending environmental monitoring signals;

[0013] A receiving node model, used to receive the environmental monitoring signal sent by the sending node model;

[0014] a medium model, coupled with the sending node model, for transmitting medium properties;

[0015] and a radio model for data communication between the sending node model and the receiving node model.

[0016] As a further improvement of the present invention, the medium is any one or more of different types of coal, rock, coal rock mass and granular solid media in non-coal fields.

[0017] As a further improvement of the present invention, the medium is a coal rock medium model, and the coal rock medium model includes a coal rock medium definition and a coal rock model construction. The coal rock medium definition includes the definition of the coal rock material parameters resistivity, relative dielectric constant and relative magnetic permeability, and the coal rock model construction includes the construction of the coal rock medium position, shape and material.

[0018] As a further improvement of the present invention, the network simulation software is OMNeT++.

[0019] As a further improvement of the present invention, in the model building process of step S1, a contact gap is set between the medium and the environmental monitoring node to achieve simulation construction of both complete coverage and incomplete coverage.

[0020] The present invention also discloses a method for establishing a communication link between multiple nodes under medium coverage, based on a method for testing the communication quality of nodes under medium coverage, comprising the following steps:

[0021] First, a discovery node without dielectric coverage is introduced. The first dielectric coverage node with which the discovery node can establish a communication connection is searched. When the discovery node and the first dielectric coverage node are connected, the coordinates of the discovery node are used as the coordinate origin, and the node antenna records the direction k of the discovery node at that time. Based on the time difference principle, the distance d between the discovery node and the first dielectric coverage node is calculated, d = (t2-t1)*v / 2, where t1 represents the time when the discovery node transmits the signal, t2 represents the time when the discovery node receives the signal, and v represents the propagation speed of electromagnetic waves.

[0022] Second, based on the results obtained in step S4, the coverage thickness range Rx of the first medium covering the node is preliminarily obtained according to the d value, and at the same time, the equation of the circle with the discovery node as the center is established as x 2 +y 2 =d 2 ;

[0023] The equation in the direction of the node covered by the first medium is y=kx;

[0024] By combining the two equations, we can find the coordinates of the node covered by the first medium;

[0025] Third, let the discovery node move in the opposite direction of the area where the first medium coverage node is located until the communication with the first medium coverage node is interrupted, and calculate the distance d2 at this time;

[0026] According to the result of step S4, the node coverage thickness range Ry corresponding to d2 can be known. Based on the intersection between Rx and Ry, the maximum coverage thickness value of the node covered by the first medium is obtained. According to the coordinates of the node covered by the first medium and the maximum coverage thickness value, the maximum communication range of the node covered by the first medium is finally determined.

[0027] Fourth, continue to use the discovery node to continue searching for other medium coverage nodes within the maximum communication range, and establish communication link connections between the first medium coverage node and other medium coverage nodes through the discovery node.

[0028] Compared with the prior art, the present invention has the following beneficial effects:

[0029] (1) A method for testing the communication quality of nodes covered by a medium, from model establishment, parameter adjustment, simulation operation to result analysis, provides a universal testing method within the INET framework, providing a reference for using this software for scientific research simulation. Moreover, the model constructed by this testing method eliminates redundant parts compared to the overall structure of the INET framework, saving computing resources. This invention is targeted at testing point-to-point communication performance in coal-rock covered media, eliminating the complex factors of ground experimental operations and preventing waste of post-experimental resources.

[0030] (2) A communication link construction method, compared with the discovery node performing arbitrary discovery work, uses the set of medium coverage thickness values ​​of the node model corresponding to the node spacing range and the set relationship between the node spacing value and the medium coverage thickness range. When the discovery node performs node discovery in the disaster area, due to the maximum communication range and neighbor table of the first medium coverage node, the efficiency of node discovery can be improved and the time of network reconstruction can be reduced. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 This is a network model framework diagram in a method for testing the communication quality of a medium coverage node according to the present invention;

[0032] Figure 2 It is a simulation construction of two situations of complete coverage and incomplete coverage between the medium and the environmental monitoring node in a medium coverage node communication quality test method of the present invention;

[0033] Figure 3 The present invention is a flowchart of a method for testing the communication quality of a medium coverage node. DETAILED DESCRIPTION

[0034] The present invention is described in detail below with reference to the various embodiments shown in the accompanying drawings, but it should be noted that these embodiments are not limitations of the present invention, and any equivalent transformations or substitutions in functions, methods, or structures made by ordinary technicians in this field based on these embodiments are all within the scope of protection of the present invention.

[0035] Please refer to Figures 1 to 3 A specific implementation of a medium coverage node communication quality testing method and a communication link establishment method of the present invention is shown.

[0036] Example 1:

[0037] A method for testing the communication quality of a medium-covered node is characterized in that it includes the following steps: S1, model establishment, based on actual disaster situations, selecting the medium type covered by the environmental monitoring node and the communication mode between the environmental monitoring node, preliminarily selecting the medium coverage thickness value of the environmental monitoring node, and constructing a network model based on network simulation software for communication testing of the environmental monitoring node; S2, parameter adjustment, adjusting the model parameters by adopting a fixed single variable method, the model parameters including the medium coverage thickness of the medium model and the spacing between the sending node model and the receiving node model; S3, running the simulation, recording the communication results, and judging whether the communication situation of the environmental monitoring node is good based on the communication results under a single simulation; S4, based on the communication results of S3, readjusting the parameters, repeating steps S2 and S3 in sequence, and testing multiple times to obtain a set of medium coverage thickness values ​​of the node model corresponding to the node spacing range that meet the communication conditions, and a set of node spacing values ​​corresponding to the medium coverage thickness range.

[0038] The network model includes: a sending node model, which is used to send environmental monitoring signals of the environmental monitoring node, including temperature, impact force, temperature, humidity, methane gas and other signals; a receiving node model, which is used to receive the environmental monitoring signals sent by the sending node model; a medium model, which is covered on the sending node model by coupling with the sending node model; and a radio model, which is used for data communication between the sending node model and the receiving node model. The relationship between the four is that the sending node model, the receiving node model, the coal rock medium model (physical environment model) and the radio model are embedded in the big framework of the network model. At the same time, the radio model is coupled to the node model. The model part corresponds to specific modules such as Figure 2 As shown in the figure, the transmitting and receiving nodes are both SensorNodes, the radio model is 802.15.4 narrowband communication, and the physical environment involves coal-rock overlying media. The medium is a coal-rock medium model, which includes coal-rock medium definition and coal-rock model construction. The coal-rock medium definition includes coal-rock material parameters such as resistivity, relative permittivity, and relative permeability; coal-rock model construction includes the construction of the medium's position, shape, and material.

[0039] In order to completely construct the model, the sending node model can generate and send data packets at equal time intervals. The sending data packets have a destination address and a data packet byte length. The receiving node model can only be used to receive data packets.

[0040] The sending node model can generate and send data packets at equal time intervals. The sending data packets have a destination address and a data packet byte length. The receiving node model can only be used to receive data packets.

[0041] During the model building process of step S1, a contact gap is set between the medium and the environmental monitoring node to achieve simulation construction of both complete coverage and incomplete coverage.

[0042] The network model also includes a visualization model. The network simulation software is OMNeT++. As an open source software, OMNeT++ is widely used by scientific researchers for its modular and component-based features.

[0043] like Figure 3 The figure shows the process of the communication test method for coal rock covering nodes. Before simulation, it is necessary to first determine the communication mode of the node according to the simulation purpose. The present invention selects 802.15.4 narrowband communication. In addition, communication modes with other communication frequencies can be selected; then, the covering medium of the node is selected, its relevant material parameters are found, and the preliminary coverage thickness range is determined; finally, a preliminary result is required through theoretical analysis to compare with the simulation results.

[0044] Example 2:

[0045] The medium is any one or more of different types of coal, rock, coal rock mass, and non-coal granular solid media. The coal rock medium in the first embodiment is replaced with other media, and the 802.15.4 narrowband communication is replaced with other communication methods.

[0046] The present invention also discloses a communication link construction method, comprising the following steps: first, introducing a discovery node under a condition of no dielectric coverage, searching for a first dielectric coverage node that can form a communication connection with the discovery node, and when the discovery node is in communication connection with the first dielectric coverage node, taking the coordinates of the discovery node as the coordinate origin, and using the node antenna to record the direction k of the discovery node at this time; based on the time difference principle, obtaining the distance d between the discovery node and the first dielectric coverage node, d = (t2-t1) * v / 2, wherein t1 represents the time when the discovery node transmits a signal, t2 represents the time when the discovery node receives a signal, and v represents the propagation speed of electromagnetic waves; second, based on the result obtained in step S4, preliminarily obtaining the coverage thickness range Rx of the first dielectric coverage node according to the d value, and at the same time establishing a circle equation with the discovery node as the center as x 2 +y 2 =d 2; The equation in the direction area where the first medium coverage node is located is y=kx; by combining the two equations, the coordinates of the first medium coverage node can be obtained; third, let the discovery node move in the opposite direction of the direction area where the first medium coverage node is located until the communication with the first medium coverage node is interrupted, and calculate the distance d2 at this time; according to the result of step S4, the node coverage thickness range Ry corresponding to d2 can be known, and the maximum coverage thickness value of the first medium coverage node is obtained based on the intersection between Rx and Ry. According to the coordinates of the first medium coverage node and the maximum coverage thickness value, the maximum communication range of the first medium coverage node is finally determined; fourth, continue to use the discovery node to continue to search for other medium coverage nodes within the maximum communication range, and establish a communication link connection between the first medium coverage node and other medium coverage nodes through the discovery node.

[0047] In addition, it should be understood that although this specification is described in terms of implementation methods, not every implementation method contains only one independent technical solution. This narrative method of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment can also be appropriately combined to form other implementation methods that can be understood by those skilled in the art.

Claims

1. A method for testing the communication quality of a medium coverage node, characterized in that: The following steps are involved: S1, model establishment, select the medium type covered by the environmental monitoring node and the communication method between the environmental monitoring node, preliminarily select the medium coverage thickness value of the environmental monitoring node, and build a network model based on network simulation software for communication testing of the environmental monitoring node; S2, parameter adjustment, uses a fixed single variable method to adjust the model parameters, including the medium coverage thickness of the medium model and the distance between the sending node model and the receiving node model; S3, run the simulation, record the communication results, and analyze and judge whether the communication status of the environmental monitoring node is good based on the communication results under a single simulation; S4, based on the communication results of S3, readjust the parameters, repeat steps S2 and S3 in sequence, and test multiple times to obtain the set of medium coverage thickness values ​​corresponding to the node spacing range of the node model that meets the communication conditions and the set of node spacing values ​​corresponding to the medium coverage thickness range.

2. A method for testing the communication quality of a medium coverage node according to claim 1, characterized in that: The network model includes: The sending node model has a sensor for environmental monitoring and is capable of sending environmental monitoring signals; A receiving node model, used to receive the environmental monitoring signal sent by the sending node model; a medium model, coupled with the sending node model, for transmitting medium properties; and a radio model for data communication between the sending node model and the receiving node model.

3. A method for testing the communication quality of a medium coverage node according to claim 1, characterized in that: The medium is any one or more of different types of coal, rock, coal rock mass and non-coal granular solid media.

4. A method for testing the communication quality of a medium coverage node according to claim 3, characterized in that: The medium is a coal rock medium model, which includes a coal rock medium definition and a coal rock model construction. The coal rock medium definition includes the definition of the coal rock material parameters resistivity, relative dielectric constant and relative magnetic permeability. The coal rock model construction includes the construction of the coal rock medium position, shape and material.

5. A method for testing communication quality of a medium coverage node according to claim 1, characterized in that: The network simulation software is OMNeT++.

6. A method for testing communication quality of a medium coverage node according to claim 1, characterized in that: During the model building process of step S1, a contact gap is set between the medium and the environmental monitoring node to achieve simulation construction of both complete coverage and incomplete coverage.

7. A communication link construction method, based on the medium coverage node communication quality testing method according to claim 1, characterized in that: The following steps are involved: First, a discovery node without dielectric coverage is introduced. The first dielectric coverage node with which the discovery node can establish a communication connection is searched. When the discovery node and the first dielectric coverage node are connected, the coordinates of the discovery node are used as the coordinate origin, and the node antenna records the direction k of the discovery node at that time. Based on the time difference principle, the distance d between the discovery node and the first dielectric coverage node is calculated, d = (t2-t1)*v / 2, where t1 represents the time when the discovery node transmits the signal, t2 represents the time when the discovery node receives the signal, and v represents the propagation speed of electromagnetic waves. Second, based on the results obtained in step S4, the coverage thickness range Rx of the first medium covering the node is preliminarily obtained according to the d value, and at the same time, the equation of the circle with the discovery node as the center is established as x 2 +y 2 =d 2 ; The equation in the direction of the node covered by the first medium is y=kx; By combining the two equations, we can find the coordinates of the node covered by the first medium; Third, let the discovery node move in the opposite direction of the area where the first medium coverage node is located until the communication with the first medium coverage node is interrupted, and calculate the distance d2 at this time; According to the result of step S4, the node coverage thickness range Ry corresponding to d2 can be known. Based on the intersection between Rx and Ry, the maximum coverage thickness value of the node covered by the first medium is obtained. According to the coordinates of the node covered by the first medium and the maximum coverage thickness value, the maximum communication range of the node covered by the first medium is finally determined. Fourth, continue to use the discovery node to continue searching for other medium coverage nodes within the maximum communication range, and establish communication link connections between the first medium coverage node and other medium coverage nodes through the discovery node.

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