阅读说明：本技术 一种基于加权距离及紧凑路由的数据传输方法 (Data transmission method based on weighted distance and compact routing ) 是由 于珊平 武祎 冯立辉 高瑞雪 陈佩雨 夏兆宇 辛喆 韩航程 李向梅 王瑞 卢继华 于 2021-06-15 设计创作，主要内容包括：本发明涉及一种基于加权距离及紧凑路由的数据传输方法,属于无线网络路由及数据传输技术领域。所述方法初始化节点各参数后,依据距离、带宽、信道质量及能量的线性叠加计算加权距离,发送查询信号并建立路由；采集信息并进行编码封装后受控制模块控制,经数据传输模块进行传输；判决节点是否有邻居节点、是否有足够多能量以及邻居是否还有其他邻居节点来决定数据传输还是该邻居节点从路由表中删除；当节点间距离变动即节点移动、信道、带宽及能量变动时,路由表会相应修改。所述方法的加权距离为混合动态加权,大大降低了运算量；采用紧凑路由与数据传输,大大提升了传输效率；同时有利于避免信息泄露和侦听,提高了信息传输的安全性。(The invention relates to a data transmission method based on weighted distance and compact routing, and belongs to the technical field of wireless network routing and data transmission. After initializing each parameter of the node, calculating a weighted distance according to linear superposition of distance, bandwidth, channel quality and energy, sending an inquiry signal and establishing a route; the information is collected, encoded and packaged, then controlled by a control module, and transmitted by a data transmission module; judging whether the node has a neighbor node, whether the node has enough energy and whether the neighbor has other neighbor nodes to decide data transmission or delete the neighbor node from the routing table; when the distance between nodes changes, i.e. the nodes move, the channel, the bandwidth and the energy change, the routing table is modified accordingly. The weighting distance of the method is mixed dynamic weighting, so that the operation amount is greatly reduced; compact routing and data transmission are adopted, so that the transmission efficiency is greatly improved; meanwhile, information leakage and interception are avoided, and the safety of information transmission is improved.)

1. A data transmission method based on weighted distance and compact routing is characterized in that: the data transmission system supported by the method comprises a plurality of nodes, wherein each node comprises a node initialization module, a control module, a routing table establishing module, an information acquisition and packaging module, a routing selection module, a judgment module, a data transmission module, a data packet discarding module and a routing table updating module;

the control module comprises a core control unit, a driving unit and a power supply unit; the information acquisition and packaging module comprises an information acquisition unit and an information coding unit; the information acquisition unit comprises a positioning unit and a sensor group; the sensor group comprises a temperature sensor, a photosensitive sensor, a smoke sensor, a sound sensor, a combustible gas sensor and a CO concentration sensor; the data transmission module comprises a data transmission unit and a wireless communication unit;

the routing module comprises a weighted distance calculation unit and a neighbor selection unit; the routing table establishing module comprises a neighbor node information collecting unit and a current node routing table establishing unit; the information acquisition and packaging module comprises an information acquisition unit and an information coding unit; the routing table updating module comprises a routing information adding unit, a routing deleting unit and a routing modifying unit; the judgment module comprises a one-hop neighbor judgment unit, a neighbor energy judgment unit, a two-hop neighbor judgment unit, a neighbor purpose judgment unit and a node movement judgment unit;

the connection relationship between each module and each unit in the data transmission system is as follows:

the node initialization module is connected with the routing module; the routing module is respectively connected with the routing table establishing module, the routing table updating module and the judging module; the information acquisition and encapsulation module is connected with the routing table updating module and the data transmission module; the decision module is respectively connected with the routing table updating module, the routing selection module, the data transmission module and the data packet discarding module, and the information acquisition and encapsulation module and the data transmission module are respectively connected with the control module; the core control unit of the control module is respectively connected with the driving unit, the power supply unit, the information coding unit of the information acquisition and packaging module and the wireless communication unit of the data transmission module;

the connection relationship between the unit and each module is as follows:

an information acquisition unit in the information acquisition and encapsulation module is connected with an information coding unit, and the information coding unit is connected with a routing information adding unit; the node initialization module is connected with the weighted distance calculation unit; the weighted distance calculation unit is respectively connected with the routing table establishment module and the routing modification unit; the routing table establishing module is connected with the neighbor selecting unit;

the neighbor selection unit is connected with the one-hop neighbor judgment unit and the neighbor energy judgment unit; the one-hop neighbor judgment unit is connected with the data packet discarding module; the neighbor energy judging unit is connected with the two-hop neighbor judging unit and the route deleting unit; the two-hop neighbor judgment unit is connected with the data transmission unit in the data transmission module and the neighbor destination judgment unit; the node movement judgment unit is connected with the weighted distance calculation unit;

the data transmission method based on the weighted distance and the compact route comprises two parts, namely route establishment and data transmission;

the route establishment comprises the following steps:

step 1, a node initialization module initializes node ID, bandwidth, maximum transmission distance, energy, signal sending times and maximum sending times;

step 2, the weighted distance calculation unit calculates the mixed weighted distance based on the distance, the bandwidth, the channel quality and the energy, and sends the calculated mixed weighted distance to the routing table establishment module;

wherein, the weighted distance is calculated according to the distance, the bandwidth, the channel quality and the energy multiplied by the coefficient for weighting;

step 3, the node judges whether the signal sending times reaches the upper limit, if so, the routing table is established, if not, the neighbor node information collection unit sends bandwidth, ID and energy inquiry signals to the periphery, and the signal sending times is added by 1;

step 4, after sending the query signal, if no feedback signal is received, skipping to step 3, otherwise, if a feedback signal is received, performing corresponding operation according to information including the node ID, the address, the bandwidth and the energy, which is fed back to the current node by the neighbor node receiving the signal, specifically: if the current node receives the feedback information, the routing information adding unit adds the encapsulated information into a routing information table, namely, the current node routing table establishing unit records the ID, the address, the bandwidth and the energy of the neighbor node in the routing table, and then jumps to the step 3;

the neighbor nodes refer to nodes of the current node within the transmission distance and electric quantity allowable range;

the routing table establishing module sends the established routing table to the neighbor selecting unit, and the neighbor selecting unit selects neighbor nodes with weighted distances in the routing table ordered from small to large;

the data transmission comprises the following steps:

step A, an information acquisition and packaging module acquires information and encodes and packages the information;

the information acquisition unit finishes information acquisition, and the information coding unit finishes coding the acquired information;

the coding mode includes, but is not limited to, parity check, CRC check, and channel coding;

b, judging whether the node has a neighbor node by a one-hop neighbor judgment unit, and if not, discarding the data packet; if yes, jumping to the step C;

discarding the data packet is completed by a data packet discarding module;

the one-hop neighbor judgment unit is used for inquiring whether a routing table has a neighbor node or not;

c, judging whether the neighbor nodes have enough energy to transmit data packets or not by the neighbor energy judging unit, if not, deleting the route by the route deleting unit, and if so, jumping to the step D;

the route deleting unit is used for deleting the route information;

d, judging whether the neighbor has other neighbor nodes by a two-hop neighbor judgment unit, if so, transmitting data by a data transmission unit or a wireless transmission unit in the data transmission module, and if not, jumping to the step E;

the two-hop neighbor judgment unit is used for judging whether the neighbor has other neighbor nodes or not; the data transmission unit is positioned in a data transmission module, and the data transmission module is used for transmitting the current data block;

e, judging whether the neighbor node is a destination node or not by a neighbor destination judgment unit, and if so, transmitting the data packet to the destination node; if not, deleting the neighbor node from the routing table;

the neighbor destination judging unit is used for judging whether the neighbor node is a destination node or not;

in addition, the node movement judging unit judges whether the node moves, and if the node moves, the route modifying unit is used for modifying the energy and the distance information in the routing table.

2. The data transmission method according to claim 1, wherein the data transmission method comprises: the number of nodes is greater than or equal to 5.

3. The data transmission method according to claim 1, wherein the data transmission method comprises: the node initialization module comprises a node ID initialization unit, a bandwidth initialization unit, a maximum transmission distance initialization unit and an energy initialization unit.

4. The data transmission method according to claim 1, wherein the data transmission method comprises: the positioning unit realizes accurate positioning of the node; the temperature, light-sensitive and smoke sensors in the sensor group are used for environment detection; the data transmission module transmits data to other nodes through the wireless communication unit.

5. The data transmission method according to claim 1, wherein the data transmission method comprises: the information coding unit codes the detected environment information and the position information; the driving unit is used for moving the node; the power supply unit supplies power to the whole system; the control unit realizes the regulation and control of other units and modules, and the information acquisition and packaging module and the data transmission module are controlled by the control module.

6. The data transmission method according to claim 1, wherein the data transmission method comprises: the routing module selects a neighbor node based on routing query; the weighted distance calculation unit calculates the weighted distance based on the distance, the bandwidth, the channel quality and the energy in a weighted manner; the route establishing unit establishes a new route table; the neighbor selection unit selects a neighbor having the smallest weighted distance from the routing table.

7. The data transmission method according to claim 1, wherein the data transmission method comprises: the neighbor energy judging unit is used for judging whether the neighbor nodes have enough energy to transmit data packets; the one-hop neighbor judgment unit is used for inquiring whether the routing table has a neighbor node or not; the two-hop neighbor judgment unit is used for judging whether the neighbor has other neighbor nodes; the neighbor destination judging unit is used for judging whether the neighbor node is a destination node or not.

8. The data transmission method according to claim 1, wherein the data transmission method comprises: the node movement judging unit is used for judging whether the node moves or not; the data transmission module is used for transmitting the current data block; the data packet discarding module is used for discarding the current data block; the routing information adding unit is used for adding the encapsulated information into a routing information table; the route deleting unit is used for deleting the route information; the route modifying unit is used for modifying the energy and distance information in the route table.

9. The data transmission method according to claim 1, wherein the data transmission method comprises: in step 2, calculating the weighted distance, specifically: a1+ a2 (1-available energy) + A3 (1-CSI channel quality) + a4 (1-bandwidth);

wherein a1+ a2+ A3+ a4 is 1, the existing energy is the percentage of the current node power relative to the nominal power, the CSI channel quality is the percentage of the current node channel quality relative to the ideal channel quality, and the bandwidth is the percentage of the current node bandwidth relative to the ideal bandwidth.

10. The data transmission method according to claim 1, wherein the data transmission method comprises: in step 1, the number of times of transmission of the initialization signal is 0, and the maximum number of times of transmission is set to be 5 or more.

Technical Field

The invention relates to a data transmission method based on weighted distance and compact routing, and belongs to the technical field of wireless network routing and data transmission.

Background

With the technical progress, the application of the wireless sensor network is more and more extensive, such as emergency, early warning and environmental monitoring. Sensor nodes are widely used in the industrial field due to the low cost, easy layout and low power consumption of many types of sensors. Sensor nodes are mostly placed in a mode of throwing by an airplane, and transmission efficiency can be greatly improved in severe conditions or field places.

Since the sensor network nodes usually use batteries to supply energy, in practical application, the node power supply is not updatable within a period of time, so that the survival time of the network is closely related to energy consumption. In addition, in an emergency application scene such as a forest fire scene, the transmission efficiency of the network plays a decisive role, and the influence of the transmission distance, the bandwidth and the channel quality on the network performance needs to be comprehensively considered. Based on this, experts and scholars at home and abroad carry out extensive research on weighted routing and cross-layer routing design, and expect to reduce network energy consumption by properly setting routing strategy search criteria and improve network transmission speed by cross-layer design.

In the existing research of weighted routing, most of the weighted routing only considers energy and shortest paths, and a large amount of summation, multiplication and division calculation is involved, so that the calculation amount is large, and the algorithm complexity is high. In the route research based on the channel characteristics, only the signal-to-noise ratio of the link is considered, and the influence of energy, bandwidth and the like is ignored. In the related cross-layer routing design, node switching, congestion and the minimum hop count are considered, and the physical Channel quality, namely, the State Information quality (CSI), is not considered.

Disclosure of Invention

The invention aims to provide a data transmission method based on a weighted distance and a compact route, aiming at the technical current situations that the existing weighted route has complicated weighted information calculation and is inflexible, thereby causing large time delay, and the transmission efficiency of cross-layer data transmission is low due to frequent switching of a physical layer and a link layer.

The core idea of the invention is as follows: after initializing each parameter of the node, calculating a weighted distance according to linear superposition of distance, bandwidth, channel quality and energy, sending an inquiry signal and establishing a route; the information is collected, encoded and packaged, then controlled by a control module, and transmitted by a data transmission module; judging whether the node has a neighbor node, whether the node has enough energy and whether the neighbor has other neighbor nodes to decide data transmission or delete the neighbor node from the routing table; when the distance between nodes changes, i.e. the nodes move, the channel, the bandwidth and the energy change, the routing table is modified accordingly.

In order to achieve the purpose, the invention adopts the following technical scheme:

the data transmission system supported by the data transmission method based on the weighted distance and the compact routing comprises a plurality of nodes, wherein each node comprises a node initialization module, a control module, a routing table establishment module, an information acquisition and encapsulation module, a routing selection module, a judgment module, a data transmission module, a data packet discarding module and a routing table updating module;

the number of the nodes is more than or equal to 5;

the control module comprises a core control unit, a driving unit and a power supply unit; the information acquisition and packaging module comprises an information acquisition unit and an information coding unit; the information acquisition unit comprises a positioning unit and a sensor group; the sensor group comprises a temperature sensor, a photosensitive sensor, a smoke sensor, a sound sensor, a combustible gas sensor and a CO concentration sensor; the data transmission module comprises a data transmission unit and a wireless communication unit;

the node initialization module comprises a node ID initialization unit, a bandwidth initialization unit, a maximum transmission distance initialization unit and an energy initialization unit; the routing module comprises a weighted distance calculation unit and a neighbor selection unit; the routing table establishing module comprises a neighbor node information collecting unit and a current node routing table establishing unit; the information acquisition and packaging module comprises an information acquisition unit and an information coding unit; the routing table updating module comprises a routing information adding unit, a routing deleting unit and a routing modifying unit; the judgment module comprises a one-hop neighbor judgment unit, a neighbor energy judgment unit, a two-hop neighbor judgment unit, a neighbor purpose judgment unit and a node movement judgment unit;

the connection relationship between each module and each unit in the data transmission system is as follows:

the node initialization module is connected with the routing module; the routing module is respectively connected with the routing table establishing module, the routing table updating module and the judging module; the information acquisition and encapsulation module is connected with the routing table updating module and the data transmission module; the decision module is respectively connected with the routing table updating module, the routing selection module, the data transmission module and the data packet discarding module, and the information acquisition and encapsulation module and the data transmission module are respectively connected with the control module; the core control unit of the control module is respectively connected with the driving unit, the power supply unit, the information coding unit of the information acquisition and packaging module and the wireless communication unit of the data transmission module;

the connection relationship between the unit and each module is as follows:

an information acquisition unit in the information acquisition and encapsulation module is connected with an information coding unit, and the information coding unit is connected with a routing information adding unit; the node initialization module is connected with the weighted distance calculation unit; the weighted distance calculation unit is respectively connected with the routing table establishment module and the routing modification unit; the routing table establishing module is connected with the neighbor selecting unit;

the neighbor selection unit is connected with the one-hop neighbor judgment unit and the neighbor energy judgment unit; the one-hop neighbor judgment unit is connected with the data packet discarding module; the neighbor energy judging unit is connected with the two-hop neighbor judging unit and the route deleting unit; the two-hop neighbor judgment unit is connected with the data transmission unit in the data transmission module and the neighbor destination judgment unit; the node movement judgment unit is connected with the weighted distance calculation unit;

the functions of each module and each unit in the data transmission system are as follows:

the positioning unit realizes accurate positioning of the node; sensors in the sensor group, such as temperature, light sensitivity, smoke and the like, are used for environment detection; the data transmission module transmits data to other nodes through the wireless communication unit; the information coding unit codes the detected environment information and the position information; the driving unit is used for moving the node; the power supply unit supplies power to the whole system; the control unit regulates and controls other units and modules, and the information acquisition and packaging module and the data transmission module are controlled by the control module; the function of the routing module is to select neighbor nodes based on routing queries; the weighted distance calculation unit calculates the weighted distance based on the distance, the bandwidth, the channel quality and the energy in a weighted manner; the route establishing unit establishes a new route table; the neighbor selection unit selects a neighbor with the minimum weighted distance from the routing table; the neighbor energy judging unit is used for judging whether the neighbor nodes have enough energy to transmit data packets; the one-hop neighbor judgment unit is used for inquiring whether the routing table has a neighbor node or not; the two-hop neighbor judgment unit is used for judging whether the neighbor has other neighbor nodes; the neighbor destination judging unit is used for judging whether the neighbor node is a destination node or not; the node movement judging unit is used for judging whether the node moves or not; the data transmission module is used for transmitting the current data block; the data packet discarding module is used for discarding the current data block; the routing information adding unit is used for adding the encapsulated information into a routing information table; the route deleting unit is used for deleting the route information; the route modifying unit is used for modifying the energy and distance information in the route table.

The data transmission method based on the weighted distance and the compact route comprises two parts, namely route establishment and data transmission;

the route establishment comprises the following steps:

step 1, a node initialization module initializes a node ID, a bandwidth, a maximum transmission distance, energy, signal sending times and a maximum sending time, and specifically includes:

initializing the signal sending times to be 0, and setting the maximum sending times to be more than or equal to 5;

step 2, the weighted distance calculation unit calculates the mixed weighted distance based on the distance, the bandwidth, the channel quality and the energy, and sends the calculated mixed weighted distance to the routing table establishment module;

wherein, the calculation of the weighted distance is weighted according to the distance, the bandwidth, the channel quality and the energy multiplied by the coefficient, and specifically comprises the following steps: a1+ a2 (1-available energy) + A3 (1-CSI channel quality) + a4 (1-bandwidth);

wherein, a1+ a2+ A3+ a4 is 1, the existing energy is the percentage of the current node power relative to the nominal power, the CSI channel quality is the percentage of the current node channel quality relative to the ideal channel quality, and the bandwidth is the percentage of the current node bandwidth relative to the ideal bandwidth;

step 3, the node judges whether the signal sending times reaches the upper limit, if so, the routing table is established, if not, the neighbor node information collection unit sends bandwidth, ID and energy inquiry signals to the periphery, and the signal sending times is added by 1;

step 4, after sending the query signal, if no feedback signal is received, skipping to step 3, otherwise, if a feedback signal is received, performing corresponding operation according to information including the node ID, the address, the bandwidth and the energy, which is fed back to the current node by the neighbor node receiving the signal, specifically: if the current node receives the feedback information, the routing information adding unit adds the encapsulated information into a routing information table, namely, the current node routing table establishing unit records the ID, the address, the bandwidth and the energy of the neighbor node in the routing table, and then jumps to the step 3;

the neighbor nodes refer to nodes of the current node within the transmission distance and electric quantity allowable range;

the routing table establishing module sends the established routing table to the neighbor selecting unit, and the neighbor selecting unit selects neighbor nodes with weighted distances in the routing table ordered from small to large;

the data transmission comprises the following steps:

step A, an information acquisition and packaging module acquires information and encodes and packages the information;

the information acquisition unit finishes information acquisition, and the information coding unit finishes coding the acquired information;

the coding mode includes, but is not limited to, parity check, CRC check, and channel coding;

b, judging whether the node has a neighbor node by a one-hop neighbor judgment unit, and if not, discarding the data packet; if yes, jumping to the step C;

discarding the data packet is completed by a data packet discarding module;

the one-hop neighbor judgment unit is used for inquiring whether a routing table has a neighbor node or not;

c, judging whether the neighbor nodes have enough energy to transmit data packets or not by the neighbor energy judging unit, if not, deleting the route by the route deleting unit, and if so, jumping to the step D;

the route deleting unit is used for deleting the route information;

d, judging whether the neighbor has other neighbor nodes by a two-hop neighbor judgment unit, if so, transmitting data by a data transmission unit or a wireless transmission unit in the data transmission module, and if not, jumping to the step E;

the two-hop neighbor judgment unit is used for judging whether the neighbor has other neighbor nodes or not; the data transmission unit is positioned in a data transmission module, and the data transmission module is used for transmitting the current data block;

e, judging whether the neighbor node is a destination node or not by a neighbor destination judgment unit, and if so, transmitting the data packet to the destination node; if not, deleting the neighbor node from the routing table;

the neighbor destination judging unit is used for judging whether the neighbor node is a destination node or not;

in addition, the node movement judging unit judges whether the node moves, and if the node moves, the route modifying unit is used for modifying the energy and the distance information in the routing table.

Advantageous effects

Compared with the existing weighted routing and cross-layer data transmission method, the data transmission method based on the weighted distance and the compact routing has the following beneficial effects:

1. the weighting distance in the method overcomes the technical defects of summation and division in the existing method, the calculation amount of the existing weighting distance is very large, the calculation load is increased, and further the network delay is increased; in the method, the weighted distance is mixed dynamic weighting, so that the limitation that only energy and the shortest path are considered in the existing method is overcome, the energy weighting in the weighted distance does not relate to division, the weight is directly weighted according to normalized energy percentage, and the operation amount is greatly reduced;

2. the method is used for compact route establishment and data transmission, and fuses a physical layer and a link layer, namely: the data measured by the physical layer is verified, information transmission of the physical layer is omitted in the routing table, and the data is transmitted only through the routing, so that the transmission efficiency and the delivery rate of data packets are greatly improved; meanwhile, information leakage is avoided, network information is effectively prevented from being intercepted, and the safety of information transmission is improved.

Drawings

FIG. 1 is a flow chart of route establishment in a data transmission method based on weighted distance and compact routing according to the present invention;

FIG. 2 is a flow chart of data transmission in a data transmission method based on weighted distance and compact routing according to the present invention;

FIG. 3 is a schematic diagram of route establishment, modification, data acquisition and data transmission of a system on which the data transmission method based on weighted distance and compact routing of the present invention relies;

FIG. 4 is a comparison graph of the implementation effect of the weighted distance calculation using only the shortest distance (4a) and considering the distance and energy (4b) when the data transmission method based on the weighted distance and the compact route is implemented according to the present invention;

fig. 5 is a diagram showing the implementation effect of the weighted distance calculation using only the shortest distance (5a) and considering the distance and channel quality (5b) when the data transmission method based on the weighted distance and the compact route is implemented according to the present invention;

fig. 6 is a diagram showing an implementation effect of calculating the weighted distance by using only the shortest distance (6a) and considering the distance and the bandwidth (6b) when the data transmission method based on the weighted distance and the compact route is implemented according to the present invention;

fig. 7 is a schematic diagram of a continuous 4-time simulation result in which the transmission distance, energy, and channel quality are comprehensively considered by the weighted distance when the data transmission method based on the weighted distance and the compact route is implemented.

Detailed Description

The following describes a data transmission method based on weighted distance and compact routing in detail with reference to specific embodiments and the accompanying drawings.

Example 1

This embodiment describes the flow of route establishment and data transmission in the data transmission method based on weighted distance and compact route and the specific implementation of the data transmission system in three operation modes.

The process of establishing the routing table is shown in fig. 1: initializing node ID, bandwidth, maximum transmission distance, energy, signal sending times and maximum sending times; calculating the actual distance to the destination node; mixing the weighted distance, and sending the calculated mixed weighted distance to a routing table establishing module; judging whether the signal sending times reach an upper limit, if so, finishing the establishment of a routing table, and if not, sending a bandwidth, ID and energy inquiry signal to the periphery by the neighbor node information collection unit, wherein the signal sending times are added by 1; after sending the query signal, if the query signal is not received, determining whether the number of signal sending times reaches an upper limit, otherwise, if the query signal is received, performing corresponding operations according to information including a node ID, an address, a bandwidth and energy, which is fed back to the current node by the neighbor node receiving the query signal, specifically: if the current node receives the feedback information, the routing information adding unit adds the encapsulated information into a routing information table, namely, the current node routing table establishing unit records the ID, the address, the bandwidth and the energy of the neighbor node in the routing table, and then judges whether the signal sending times reaches the upper limit; the neighbor nodes refer to nodes of the current node within the transmission distance and electric quantity allowable range; the routing table establishing module sends the established routing table to the neighbor selecting unit, and the neighbor selecting unit selects neighbor nodes with weighted distances in the routing table ordered from small to large.

The data transmission process is shown in fig. 2: collecting information and encoding and packaging the information; the encoding method includes, but is not limited to, parity check, CRC check, and channel coding. In specific implementation, the acquired sensor information is 32 bits by applying the method; wherein, 8 bit temperature; 8 bit humidity; 8 bits of light intensity; 8 bit smoke concentration; the four kinds of collected information are verified, and can also be elaborated after channel coding; the redundancy check mode may be one or a centralized combination of parity check, CRC check, interleaving, and channel coding. Such information transmission using compact routing transmits data only through the routing. The physical layer transmission link is omitted, and the transmission efficiency is greatly improved.

Then, a one-hop neighbor judgment unit judges whether the node has a neighbor node or not, and if not, the data packet is discarded; if yes, the neighbor selection unit selects the neighbor node with the minimum weighting distance, then the one-hop neighbor judgment unit inquires whether the neighbor node has enough energy to transmit the data packet, if not, the route is deleted through the route deletion unit, and if yes, the two-hop neighbor judgment unit is jumped in to perform corresponding operation; the route deleting unit is used for deleting the route information;

the operation process of the two-hop neighbor judgment unit is as follows: judging whether the neighbor has other neighbor nodes or not, if so, transmitting data through a data transmission unit or a wireless transmission unit in the data transmission module, otherwise, jumping to the operation of a neighbor destination judgment unit to judge whether the neighbor node is a destination node or not;

the two-hop neighbor judgment unit is used for judging whether the neighbor has other neighbor nodes or not; the data transmission unit is positioned in a data transmission module, and the data transmission module is used for transmitting the current data block;

wherein, the neighbor purpose decision unit operation bit: judging whether the neighbor node is a destination node, if so, transmitting the data packet to the destination node; if not, deleting the neighbor node from the routing table;

in addition, the node movement judging unit judges whether the node moves, and if the node moves, the route modifying unit is used for modifying the energy and distance information in the routing table.

FIG. 3 is a schematic diagram of the composition and connection of a data transmission system upon which a data transmission method based on weighted distance and compact routing of the present invention relies;

the data transmission system supported by the data transmission method based on the weighted distance and the compact routing comprises a plurality of nodes, wherein each node comprises a node initialization module, a control module, a routing table establishment module, an information acquisition and encapsulation module, a routing selection module, a judgment module, a data transmission module, a data packet discarding module and a routing table updating module;

the data transmission system comprises a plurality of nodes, wherein each node comprises a node initialization module, a control module, a routing table establishment module, an information acquisition and encapsulation module, a routing selection module, a judgment module, a data transmission module, a data packet discarding module and a routing table updating module;

the number of the nodes is more than or equal to 5, and in a large-scale complex network such as a forest fire scene, the area range can reach thousands of hectares, and thousands of network nodes are needed. When the method is implemented specifically, the method is flexibly arranged according to the size of the environment scale; the maximum capacity of a node can be up to 20 ten thousand. The number of nodes can be as small as 5 in view of indoor environment monitoring.

The distribution space density range of the acquisition equipment is as follows: the forest space is 100 x 100 meters, and the arrangement of the acquisition devices is considered to be 5 to 20.

The control module comprises a core control unit, a driving unit and a power supply unit; the information acquisition and packaging module comprises an information acquisition unit, an information coding unit and an internal memory; the information acquisition unit comprises a positioning unit and a sensor group; the sensor group comprises a temperature sensor, a photosensitive sensor, a smoke sensor, a sound sensor, a combustible gas sensor and a CO concentration sensor; the data transmission module comprises a data transmission unit and a wireless communication unit;

the internal memory is used for storing environment and positioning information collected by the sensor group in each mode;

the node initialization module comprises a node ID initialization unit, a bandwidth initialization unit, a maximum transmission distance initialization unit and an energy initialization unit; the routing module comprises a weighted distance calculation unit and a neighbor selection unit; the routing table establishing module comprises a neighbor node information collecting unit and a current node routing table establishing unit; the information acquisition and packaging module comprises an information acquisition unit and an information coding unit; the routing table updating module comprises a routing information adding unit, a routing deleting unit and a routing modifying unit; the judgment module comprises a one-hop neighbor judgment unit, a neighbor energy judgment unit, a two-hop neighbor judgment unit, a neighbor purpose judgment unit and a node movement judgment unit;

the connection relationship between each module and each unit in the data transmission system is as follows:

the node initialization module is connected with the routing module; the routing module is respectively connected with the routing table establishing module, the routing table updating module and the judging module; the information acquisition and encapsulation module is connected with the routing table updating module and the data transmission module; the decision module is respectively connected with the routing table updating module, the routing selection module, the data transmission module and the data packet discarding module, and the information acquisition and encapsulation module and the data transmission module are respectively connected with the control module; the core control unit of the control module is respectively connected with the driving unit, the power supply unit, the information coding unit of the information acquisition and packaging module and the wireless communication unit of the data transmission module;

the connection relationship between the unit and each module is as follows:

an information acquisition unit in the information acquisition and encapsulation module is connected with an information coding unit, and the information coding unit is connected with a routing information adding unit; the node initialization module is connected with the weighted distance calculation unit; the weighted distance calculation unit is respectively connected with the routing table establishment module and the routing modification unit; the routing table establishing module is connected with the neighbor selecting unit; the neighbor selection unit is connected with the one-hop neighbor judgment unit and the neighbor energy judgment unit; the one-hop neighbor judgment unit is connected with the data packet discarding module; the neighbor energy judging unit is connected with the two-hop neighbor judging unit and the route deleting unit; the two-hop neighbor judgment unit is connected with the data transmission unit in the data transmission module and the neighbor destination judgment unit; the node movement judging unit is connected with the weighted distance calculating unit.

In specific implementation, 3a and 3b are respectively module connection diagrams of a supported transmission system, and 3b focuses on information acquisition, packaging and transmission; 3a focuses on route generation, modification and deletion; in specific implementation, the two figures 3a and 3b can be combined into one; the control module can further receive a control instruction transmitted from an external upper computer interface, so that not only can the selection and control of information acquisition and packaging, namely a coding mode be realized, but also the communication with each module in the 3a can be realized according to the instruction, and the functions of route display, planning and display are realized.

Example 2

The data transmission method has the following three operation modes:

1) fire hazard mode: the system is used for adjusting the working period of each module in the supported data transmission system to be less than or equal to 10 minutes by the core control unit according to the forest fire occurrence period, acquiring the sensor group and the positioning information, and reporting the information. In the specific implementation: at the emergency moment of a fire scene, after the initialization of the nodes is completed, the node movement judgment module judges once every minute, and sends a signal to the core control unit after the judgment is successful, so that the control positioning unit transmits the position information to the information coding unit, the information acquisition unit transmits the position information of the information joint node acquired every minute to the information coding unit for coding and packaging, a data packet is added into a routing table after coding, and the acquired information is transmitted to the remote control terminal for monitoring and displaying through the wireless communication unit in the data transmission module.

2) The environment perception mode comprises the following steps: the core control unit adjusts the data transmission period to be half an hour to sense the environment and the positioning information transmitted by the sensor group once in the mode; the node movement judging module judges that the period is adjusted to be in the unit of hours, when one period is over or when the environment information acquired by the node is abnormal, such as the temperature information is larger than a certain threshold value, the core control unit sends a data transmission instruction to the information acquisition and packaging module, encodes and packages the information acquired by the sensor group, adds the data packet into the routing table and then transmits the data packet to the terminal.

3) Static mode: the core control unit adjusts the power supply unit to be in a low-consumption mode in the mode, and the data transmission module and the driving module are in a dormant state. And only when the core control unit receives an information acquisition instruction, the core control unit commands the driving unit to start to operate, the positioning unit carries out accurate positioning, and the information acquisition and packaging module carries out information encoding, packaging and transmission. When the instruction is not received, all the modules are in a dormant state, and the information acquisition and packaging module stores acquired information in the modules until the instruction is received and then performs data transmission.

In order to be close to the actual information transmission condition, the simulation is added with as many nodes as possible, a source node and two destination nodes are arranged, and data transmission simulation of 4 weighted distances is carried out, wherein the destination nodes are displayed in a hexagonal star shape.

(1) Simulation examples and results are shown in fig. 4. In fig. 4, the weight a1 of the transmission distance is set to 1, and when the effects of energy, channel quality and bandwidth are not considered, the simulation result is as shown in fig. 4a, and the source node at the lower right of the figure will select the transmission path according to the shortest distance principle. After considering both distance and energy, the simulation result is shown in fig. 4b, which is a graph that the transmission distance is increased compared with fig. 4a because the existing energy of the distant node is higher and is more dominant in the weight part.

Although the transmission distance may be increased after adding energy considerations, the reliability of the method is significantly enhanced. If only the shortest distance principle is followed, once the energy of a certain node on a path is too low or zero, the node fails, and finally transmission failure is caused, which greatly affects the transmission efficiency, and especially in a large-scale network such as a forest, the reduction of the transmission efficiency obviously attacks the network performance.

(2) When the weight a1 of the transmission distance is set to 1, and the effect of energy, channel quality and bandwidth is not considered, the simulation result is shown in fig. 5a, and the source node above the graph will select the transmission path according to the shortest distance principle. After considering both the distance and the channel quality, the simulation result is shown in fig. 5b, and the transmission distance is increased because the channel quality of the remote node is higher and more dominant in the weight part. Although the transmission distance of fig. 5b is increased, the transmission success rate of the data packet can be ensured by increasing the weight of the channel quality, and multiple simulations show that the transmission success rate of the single path of fig. 5a is 15% and the transmission success rate of the single path of fig. 5b is 30%.

(3) When the weight a1 of the transmission distance is set to 1, and the influence of other parameters is not considered, the simulation result is shown in fig. 6a, and the source node above the graph will select the transmission path according to the shortest distance principle. And after simultaneously considering the distance and the bandwidth, the simulation result is shown as 6b, and the transmission distance and the hop count are not obviously changed. But the total bandwidth of the 6b transmission path increases and the calculation weight becomes more dominant. Although there is no significant difference in the transmission distance between the two figures, the larger bandwidth of the 6b figure makes the transmission speed faster.

(4) If the influence of transmission distance, energy and channel quality is considered comprehensively during simulation, the energy value of the node is reduced and the occupied weight of the node is reduced after multiple transmissions, so that routing switching is caused, and the link transmission efficiency is improved. Fig. 7a, 7b, 7c and 7d show the results of four consecutive transmissions, it can be seen that the change in energy results in a change in the transmission path, and even that the data is transmitted to a different destination node.

In conclusion, compared with the traditional method, the data transmission method provided by the invention overcomes the defects of low node energy, short network survival time, reduced transmission efficiency and even link transmission failure in the traditional method. The high efficiency and the reliability of data transmission are ensured, and the survival time of the sensor network is prolonged.

While the foregoing is directed to the preferred embodiment of the present invention, it is not intended that the invention be limited to the embodiment and the drawings disclosed herein. Equivalents and modifications may be made without departing from the spirit of the disclosure, which is to be considered as within the scope of the invention.