CN105357732A - Wireless sensor network edge node recognition method independent of position information - Google Patents

Wireless sensor network edge node recognition method independent of position information Download PDF

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Publication number
CN105357732A
CN105357732A CN201510915450.8A CN201510915450A CN105357732A CN 105357732 A CN105357732 A CN 105357732A CN 201510915450 A CN201510915450 A CN 201510915450A CN 105357732 A CN105357732 A CN 105357732A
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node
hop neighbor
wireless sensor
sensor network
present
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CN105357732B (en
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刘文怡
赵利辉
王红亮
董和磊
苏淑靖
何志英
谭秋林
沈三民
张斌
熊继军
崔永俊
刘俊
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North University of China
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    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04W—WIRELESS COMMUNICATION NETWORKS
    • H04W40/00—Communication routing or communication path finding
    • H04W40/24—Connectivity information management, e.g. connectivity discovery or connectivity update
    • H04W40/246—Connectivity information discovery
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04W—WIRELESS COMMUNICATION NETWORKS
    • H04W84/00—Network topologies
    • H04W84/18—Self-organising networks, e.g. ad-hoc networks or sensor networks

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  • Computer Networks & Wireless Communication (AREA)
  • Signal Processing (AREA)
  • Mobile Radio Communication Systems (AREA)

Abstract

The invention provides a wireless sensor network edge node recognition method independent of position information. The method comprises the steps: firstly determining a 1-hop neighbor node and a 2-hop neighbor node of a current node; determining a 2-hop neighbor of the current node and determining whether the combination set of the 1-hop neighbor and 2-hop neighbor can form a closed loop or not; determining the shortest path tree T of a control node in the closed loop; determining the current node to be an edge node if the depth of the shortest path tree T is less than 3, or else, compressing the closed loop; and judging the current node to be the edge node if the compressed closed loop comprises the 2-hop neighbor node of the current node. The method can precisely recognize a boundary node in a wireless sensor network through employing node connection information and a node surrounding enclosing thought, achieves the recognition of the edge of the wireless sensor network and the edge node of a coverage hole under the condition of no node coordinate position information based on the connection information between nodes, and irons out a defect that a conventional recognition algorithm needs node position information. The recognition precision is greater than 90%.

Description

Do not rely on the wireless sensor network fringe node recognition methods of positional information
Technical field
The present invention relates to a kind of wireless sensor network fringe node recognition methods not relying on positional information, belong to wireless sensor network technology field.
Background technology
Under the driving of microelectromechanical systems and wireless communication technology, modern wireless sensor node has low cost of manufacture, it is low in energy consumption to use, volume is little and carry out the feature of short haul connection, it can the multiple physical environment of perception, has great potential using value in military and civilian field.The self-organizing type network that can carry out multi-hop communication that wireless sensor network is made up of the sensor node of One's name is legion, usually adopts airborne mode of shedding to be deployed in danger or region that nobody stands fast at performs monitoring task.
The key factor weighing wireless sensor network service quality is the network coverage, but due to the restriction of wireless sensor network disposition mode, node sheds the key factor that uneven formed covering cavity becomes its service quality of restriction, and unattended working method is that sensor node is very easy to suffer outside destroy and node power consumption and lost efficacy thus to produce more larger coverings empty.The service quality that the generation covering cavity not only constrains wireless sensor network causes monitoring unsuccessfully, and Monitoring Data cannot transmit or transmit mistake.Thus covering cavity is unavoidable problem in wireless sensor network investigation and application.
For the empty problem of covering, propose some corresponding solutions in existing research, existing fringe node recognition methods is divided three classes: based on node geo-location information, Corpus--based Method method and the method based on topology.But exist in current scheme and require high to network node degree, the problem that energy consumption is high and accuracy of identification is low.
Summary of the invention
In order to solve the deficiencies in the prior art, the invention provides a kind of wireless sensor network fringe node recognition methods not relying on positional information, utilize node link information and the wrapped thought of enclosing of node cycle accurately can identify boundary node in wireless sensor network, accuracy of identification reaches more than 90%.
The technical scheme that the present invention adopts for its technical problem of solution is: provide a kind of wireless sensor network fringe node recognition methods not relying on positional information, comprise the following steps:
(1) 1 hop neighbor node and the 2 hop neighbor nodes of each node in wireless sensor network are confirmed;
(2) using the node of in wireless sensor network as present node, search present node all 2 hop neighbor nodes,
(2a) judge that can all 2 hop neighbor nodes of present node form a closed hoop; If can, then enter step (3); Otherwise enter step (2b);
(2b) judge that can 2 hop neighbor nodes and the 1 hop neighbor node of present node form closed hoop, if can, enter step (5); Otherwise present node is boundary node, enter step (9);
(3) 12 hop neighbor of Stochastic choice present node are as Controlling vertex, take Controlling vertex as the 2 hop neighbor nodes generation shortest path tree Ts of root node for present node;
(4) if the degree of depth of shortest path tree T is less than 3, then present node is fringe node, enters step (9); Otherwise enter step (5) and start compression close ring;
(5) 2 hop neighbor nodes in closed hoop are selected, judge whether this 2 hop neighbor node meets the following conditions: this 2 hop neighbor node is 1 hop neighbor node of more than 21 hop neighbor nodes of present node simultaneously, and at least 2 nodes 1 hop neighbor node each other in described more than 21 hop neighbor nodes;
(6) if this 2 hop neighbor node meets step (5) described condition, then by more than 21 hop neighbor node city closed hoops of the present node described in step (5), the limit of the 2 hop neighbor nodes and connection thereof that meet step (5) described condition is deleted from closed hoop; The described 2 hop neighbor nodes meeting step (5) described condition are adhesion node; If this 2 hop neighbor node does not meet step (5) described condition, then enter step (8);
(7) step (5) is repeated to step (6) until each 2 hop neighbor nodes of closed hoop are finished;
(8) if the closed hoop after compression only comprises 1 hop neighbor node of present node, then present node is internal node; If closed hoop comprises 2 hop neighbor nodes of present node, then present node is fringe node;
(9) step (2) is repeated to step (8), until each node in wireless sensor network judges complete.
In step (1), 1 hop neighbor node and the 2 hop neighbor nodes of each node in wireless sensor network are confirmed: in wireless sensor network, each node comprises the request message of self ID and dump energy by broadcast transmission, and this node sending request message is broadcast node by following steps; Adjacent node is if receive the request message of this broadcast node, then adjacent node is in the communication range of broadcast node, and oneself is set to 1 hop neighbor node of broadcast node by adjacent node, returns to it response message comprising self ID and dump energy; Broadcast node checks after receiving response message whether adjacent node is present in the 1 hop neighbor table of oneself, if there is no then adjacent node is added into 1 hop neighbor table; After the threshold time arranged, broadcast node no longer receives response message, and sends exchange message to its all 1 hop neighbor node; Send the 1 hop neighbor table of oneself after neighbor node receives and exchanges message to broadcast node, broadcast node determines its 2 hop neighbor node according to this 1 hop neighbor table.
Broadcast node passes through its 2 hop neighbor node of following formulae discovery according to this 1 hop neighbor table:
N 2 ( S R N ) = ∪ S u ∈ N 1 ( S R N ) N 1 ( S u ) - N 1 ( S R N ) - { S R N } ... - - - ( 1 )
Wherein, S rNrepresent broadcast node, S urepresent S rN1 hop neighbor neighbor node, N 1(S rN) represent S rN1 hop neighbor set of node, N 2(S rN) represent S rN2 hop neighbor sets of node, N 1(S u) represent S u1 hop neighbor set of node, by 1 hop neighbor table obtain.
The present invention is based on the beneficial effect that its technical scheme has to be:
(1) present invention achieves when without when node coordinate positional information based on the network edge of the link information identification wireless sensor network between node and cover cavity fringe node, solve the defect that tional identification algorithm needs node location information;
(2) the present invention is due to the lower deployment cost not needing node location information to reduce wireless sensor network, has expanded its range of application, such as the inferior environment that cannot obtain node location information;
(3) the present invention does not rely on positional information, effectively reduces node owing to locating the high energy consumption problem brought;
(4) the present invention does not need positioner, effectively reduces the volume of node;
(5) algorithm complex of the present invention is low, saves running time, and only need 2 hop node information can complete the accurate identification of edge node, accuracy of identification reaches more than 90%.
Accompanying drawing explanation
Fig. 1 is the initial schematic diagram of network configuration.
Fig. 2 is the 2 hop neighbor ring schematic diagrames that dotted line Controlling vertex builds.
Fig. 3 is the single 2 hop node schematic diagrames of closed hoop compression.
Fig. 4 is the schematic diagram after all qualified 2 hop nodes of closed hoop compression.
Fig. 5 is schematic flow sheet of the present invention.
Embodiment
Below in conjunction with drawings and Examples, the invention will be further described.
The invention provides a kind of wireless sensor network fringe node recognition methods not relying on positional information, with reference to Fig. 5, comprise the following steps:
(1) 1 hop neighbor node and the 2 hop neighbor nodes of each node in wireless sensor network are confirmed;
1 hop neighbor node and the 2 hop neighbor nodes of each node in wireless sensor network can be confirmed: in wireless sensor network, each node comprises the request message (Hello_request) of self ID and dump energy by broadcast transmission, and this node sending request message is broadcast node by following process; Adjacent node is if receive the request message of this broadcast node, then adjacent node is in the communication range of broadcast node, oneself is set to 1 of broadcast node and jumps (1hop) neighbor node by adjacent node, returns to it response message (Hello_response) comprising self ID and dump energy; Broadcast node checks after receiving response message whether adjacent node is present in the 1 hop neighbor table of oneself, if there is no then adjacent node is added into 1 hop neighbor table; After the threshold time arranged, broadcast node no longer receives response message, and sends exchange message (Hello_switch) to its all 1 hop neighbor node; Send the 1 hop neighbor table of oneself after neighbor node receives and exchanges message to broadcast node, broadcast node determines its 2 jumping (2hop) neighbor node according to this 1 hop neighbor table;
Broadcast node passes through its 2 hop neighbor node of following formulae discovery according to this 1 hop neighbor table:
N 2 ( S R N ) = ∪ S u ∈ N 1 ( S R N ) N 1 ( S u ) - N 1 ( S R N ) - { S R N } ... - - - ( 1 )
Wherein, S rNrepresent broadcast node, S urepresent S rN1 hop neighbor neighbor node, N 1(S rN) represent S rN1 hop neighbor set of node, N 2(S rN) represent S rN2 hop neighbor sets of node, N 1(S u) represent S u1 hop neighbor set of node, by 1 hop neighbor table obtain.
(2) using the node of in wireless sensor network as present node, search present node all 2 hop neighbor nodes,
(2a) judge that can all 2 hop neighbor nodes of present node form a closed hoop; If can, then enter step (3); Otherwise enter step (2b);
(2b) judge that can 2 hop neighbor nodes and the 1 hop neighbor node of present node form closed hoop, if can, enter step (5); Otherwise present node is boundary node, enter step (9);
(3) 12 hop neighbor of Stochastic choice present node are as Controlling vertex, take Controlling vertex as the 2 hop neighbor nodes generation shortest path tree Ts of root node for present node;
With reference to Fig. 1, choose node 15 as present node, its all 2 hop neighbor nodes can form a closed hoop, using node 32 as Controlling vertex, build shortest path tree T with its root node, its degree of depth is obviously greater than 3, with Controlling vertex 32 for starting point, DFS and shortest path thought or greedy algorithm is utilized to build the closed hoop of all 2hop nodes, i.e. the loop of dotted line signal in Fig. 2,32 → 34 → 35 → 38 → 39 → 40 → 41 → 42 → 18 → 2 → 9 → 12 → 13 → 32.
(4) if the degree of depth of shortest path tree T is less than 3, then present node is fringe node, enters step (9); Otherwise enter step (5) and start compression close ring;
With reference to Fig. 2, the degree of depth of shortest path tree T is obviously greater than 3, enters step (5).
(5) 2 hop neighbor nodes in closed hoop are selected, judge whether this 2 hop neighbor node meets the following conditions: this 2 hop neighbor node is 1 hop neighbor node of more than 21 hop neighbor nodes of present node simultaneously, and at least 2 nodes 1 hop neighbor node each other in described more than 21 hop neighbor nodes;
With reference to Fig. 2, node 35 is common 1 hop neighbor nodes of 1 hop neighbor node 33 and 37 of present node 15, and 33 and 37 1 hop neighbor nodes each other, so node 35 meets condition described in this step.
(6) if this 2 hop neighbor node meets step (5) described condition, then by more than 21 hop neighbor node city closed hoops of the present node described in step (5), the limit of the 2 hop neighbor nodes and connection thereof that meet step (5) described condition is deleted from closed hoop; The described 2 hop neighbor nodes meeting step (5) described condition are adhesion node; If this 2 hop neighbor node does not meet step (5) described condition, then enter step (8);
With reference to Fig. 3, delete 2 hop neighbor nodes 35 and two limits thereof of present node, the limit of deletion is indicated by the solid line, and new limit of inserting is represented by dashed line.
(7) step (5) is repeated to step (6) until each 2 hop neighbor nodes of closed hoop are finished;
With reference to Fig. 4, repeat said process, as shown in Figure 4, after compression around present node closed hoop be: 32 → 34 → 33 → 37 → 36 → 16 → 17 → 11 → 10 → 14 → 32.
(8) if the closed hoop after compression only comprises 1 hop neighbor node of present node, then present node is internal node; If closed hoop comprises 2 hop neighbor nodes of present node, then present node is fringe node;
Closed hoop due to present node in Fig. 4 15 also comprises 2 hop neighbor nodes 32, so node 15 is fringe node.
(9) step (2) is repeated to step (8), until each node in wireless sensor network judges complete;
As shown in Figure 4, another can also be found to cover cavity: 1 → 2 → 3 → 4 → 5 → 6 → 1.

Claims (3)

1. do not rely on a wireless sensor network fringe node recognition methods for positional information, it is characterized in that comprising the following steps:
(1) 1 hop neighbor node and the 2 hop neighbor nodes of each node in wireless sensor network are confirmed;
(2) using the node of in wireless sensor network as present node, search present node all 2 hop neighbor nodes,
(2a) judge that can all 2 hop neighbor nodes of present node form a closed hoop; If can, then enter step (3); Otherwise enter step (2b);
(2b) judge that can 2 hop neighbor nodes and the 1 hop neighbor node of present node form closed hoop, if can, enter step (5); Otherwise present node is boundary node, enter step (9);
(3) 12 hop neighbor of Stochastic choice present node are as Controlling vertex, take Controlling vertex as the 2 hop neighbor nodes generation shortest path tree Ts of root node for present node;
(4) if the degree of depth of shortest path tree T is less than 3, then present node is fringe node, enters step (9); Otherwise enter step (5) and start compression close ring;
(5) 2 hop neighbor nodes in closed hoop are selected, judge whether this 2 hop neighbor node meets the following conditions: this 2 hop neighbor node is 1 hop neighbor node of more than 21 hop neighbor nodes of present node simultaneously, and at least 2 nodes 1 hop neighbor node each other in described more than 21 hop neighbor nodes;
(6) if this 2 hop neighbor node meets step (5) described condition, then by more than 21 hop neighbor node city closed hoops of the present node described in step (5), the limit of the 2 hop neighbor nodes and connection thereof that meet step (5) described condition is deleted from closed hoop; The described 2 hop neighbor nodes meeting step (5) described condition are adhesion node;
(7) step (5) is repeated to step (6) until each 2 hop neighbor nodes of closed hoop are finished;
(8) if the closed hoop after compression only comprises 1 hop neighbor node of present node, then present node is internal node; If closed hoop comprises 2 hop neighbor nodes of present node, then present node is fringe node;
(9) step (2) is repeated to step (8), until each node in wireless sensor network judges complete.
2. the wireless sensor network fringe node recognition methods not relying on positional information according to claim 1, it is characterized in that: in step (1), 1 hop neighbor node and the 2 hop neighbor nodes of each node in wireless sensor network are confirmed: in wireless sensor network, each node comprises the request message of self ID and dump energy by broadcast transmission, and this node sending request message is broadcast node by following process; Adjacent node is if receive the request message of this broadcast node, then adjacent node is in the communication range of broadcast node, and oneself is set to 1 hop neighbor node of broadcast node by adjacent node, returns to it response message comprising self ID and dump energy; Broadcast node checks after receiving response message whether adjacent node is present in the 1 hop neighbor table of oneself, if there is no then adjacent node is added into 1 hop neighbor table; After the threshold time arranged, broadcast node no longer receives response message, and sends exchange message to its all 1 hop neighbor node; Send the 1 hop neighbor table of oneself after neighbor node receives and exchanges message to broadcast node, broadcast node determines its 2 hop neighbor node according to this 1 hop neighbor table.
3. the wireless sensor network fringe node recognition methods not relying on positional information according to claim 2, is characterized in that: in step (1), and broadcast node utilizes 1 hop neighbor table of this node by its 2 hop neighbor node of following formulae discovery:
Wherein, S rNrepresent broadcast node, S urepresent S rN1 hop neighbor neighbor node, N 1(S rN) represent S rN1 hop neighbor set of node, N 2(S rN) represent S rN2 hop neighbor sets of node, N 1(S u) represent S u1 hop neighbor set of node, by 1 hop neighbor table obtain.
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CN109257763A (en) * 2018-10-22 2019-01-22 安徽工业大学 The judgment method of wireless sensor two-dimensional network boundary node
CN111683376A (en) * 2020-06-02 2020-09-18 中北大学 Optimized deployment method for nodes of field collaborative irrigation communication network
CN113988628A (en) * 2021-10-28 2022-01-28 中国银行股份有限公司 ATM position determining method and system

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Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN109195174A (en) * 2018-08-29 2019-01-11 安徽工业大学 A kind of boundary node determination method based on regional area projection
CN109195174B (en) * 2018-08-29 2021-07-09 安徽工业大学 Boundary node judgment method based on local area projection
CN109257763A (en) * 2018-10-22 2019-01-22 安徽工业大学 The judgment method of wireless sensor two-dimensional network boundary node
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CN111683376A (en) * 2020-06-02 2020-09-18 中北大学 Optimized deployment method for nodes of field collaborative irrigation communication network
CN111683376B (en) * 2020-06-02 2022-06-24 中北大学 Optimized deployment method for nodes of field collaborative irrigation communication network
CN113988628A (en) * 2021-10-28 2022-01-28 中国银行股份有限公司 ATM position determining method and system
CN113988628B (en) * 2021-10-28 2024-10-15 中国银行股份有限公司 ATM (automatic teller machine) position determining method and system

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