阅读说明：本技术 二维无线传感器网络覆盖漏洞的修复方法 (Two-dimensional wireless sensor network coverage hole repairing method ) 是由 张玖雅 卫琳娜 郭会 吴宣够 于 2019-08-29 设计创作，主要内容包括：本发明公开一种二维无线传感器网络的漏洞修复方法,涉及无线传感器网络领域,包括如下步骤：1)激活无线传感器网络中移动节点,计算二维无线传感器网络中各覆盖漏洞的最大面积,以及修复各覆盖漏洞需要的移动节点的个数；2)移动节点选择移动的目标覆盖漏洞；3)移动节点选择移动路径,并按照选择的移动路径移动至目标覆盖漏洞的边界节点处；4)到达目标覆盖漏洞附近的移动节点计算其在目标覆盖漏洞中的相对位置并进行漏洞修复；本发明能在本地端完成,节点之间通信较少,且移动距离相对较短,无需节点位置坐标即可修复网络中的覆盖漏洞。(The invention discloses a vulnerability repairing method of a two-dimensional wireless sensor network, which relates to the field of wireless sensor networks and comprises the following steps: 1) activating mobile nodes in the wireless sensor network, calculating the maximum area of each coverage hole in the two-dimensional wireless sensor network, and the number of the mobile nodes required for repairing each coverage hole; 2) the mobile node selects a moving target coverage hole; 3) the mobile node selects a moving path and moves to a boundary node of the target coverage hole according to the selected moving path; 4) calculating the relative position of the mobile node in the target coverage hole and repairing the hole by the mobile node reaching the vicinity of the target coverage hole; the method can be completed at a local end, the communication among the nodes is less, the moving distance is relatively short, and the coverage hole in the network can be repaired without the position coordinates of the nodes.)

1. A method for repairing a two-dimensional wireless sensor network coverage hole is characterized by comprising the following steps:

1) activating mobile nodes arranged in the two-dimensional wireless sensor network, calculating the maximum area of each coverage hole in the two-dimensional wireless sensor network, and repairing the number of the mobile nodes at least needed by each coverage hole;

2) the mobile node selects a moving target coverage hole;

3) the mobile node selects a moving path and moves to a boundary node of the target coverage hole according to the selected moving path;

4) and calculating the relative position of the mobile node reaching the boundary node of the target coverage hole in the target coverage hole and repairing the coverage hole.

2. The two-dimensional wireless sensor network coverage hole repairing method according to claim 1, wherein the method for calculating the coverage hole area in step 1) is to calculate the perimeter of each coverage hole by combining the known number of boundary nodes of each coverage hole with the induction radius of the node, and calculate the maximum area of each coverage hole according to the principle that the area of a circle is the largest in the same perimeter;

when the maximum area of the coverage hole calculated by the area of the circle is defined, the coverage hole is recorded as a coverage hole circle;

the area formula of the coverage hole circle is:

L＝(n/k)*2*sr (1-1)

R＝L/(2*pi) (1-2)

S＝pi*R^2 (1-3)

wherein n is the number of boundary nodes covering the vulnerability, L is the perimeter of the vulnerability, k is the coverage of the two-dimensional wireless sensor network, sr is the sensing radius of the nodes, R is the radius of a vulnerability covering circle, S is the area of the vulnerability covering circle, and pi is the circumferential rate;

then the number N of mobile nodes required by the coverage hole circle with the repair area S is at least the ratio of the area of the coverage hole circle to the area of the mobile node induction, that is:

。

3. the two-dimensional wireless sensor network coverage hole repairing method according to claim 1, wherein the step 2) of selecting a moving target coverage hole for any mobile node comprises the following steps:

(1.1) any mobile node is marked as A, finding out neighbor nodes capable of communicating within five hops of A, and recording the sequence of the neighbor nodes and the id of each neighbor node;

(1.2) when the neighbor nodes within the five hops of A comprise the boundary nodes of the coverage holes, the communication between the A and the coverage holes is successful;

(1.3) after the communication of the five-hop neighbor nodes of all the mobile nodes is finished, sequencing the mobile nodes which are successfully communicated with each coverage hole according to the hop count of the nodes, selecting the first N sequenced mobile nodes according to the area of a coverage hole circle, and sending a return message which comprises a node id which is passed by the communication, the hop count between the mobile node and the coverage hole, and a boundary node id for the communication between the mobile node and the coverage hole; the information of the mobile nodes sequenced after N is reserved for standby;

(1.4) when the mobile node receives a single coverage hole and returns a message according to a reverse path of the received information sent by the mobile node, the mobile node directly selects the coverage hole as a target coverage hole and moves to a boundary node of the target coverage hole; when the mobile node receives the return messages of a plurality of coverage holes, the mobile node selects the coverage hole with the more recent node hop number as a target coverage hole and moves to the boundary node of the target coverage hole;

(1.5) when all the mobile nodes receiving the return message have moved to the boundary nodes of the corresponding target coverage holes, each coverage hole respectively detects whether the number of the mobile nodes positioned at the boundary nodes is enough to repair the coverage holes: when the coverage loophole detects that the number of the mobile nodes positioned at the boundary node of the coverage loophole is enough to repair the coverage loophole, releasing the stored node information; and (3) when the coverage hole detects that the number of the mobile nodes positioned at the boundary node of the coverage hole is not enough to repair the coverage hole, sequentially sending return messages to the mobile nodes sequenced after N according to the sequencing in the step (1.3), and waiting for the subsequent mobile nodes to move to the boundary node corresponding to the coverage hole until the number of the mobile nodes positioned at the boundary node of the coverage hole is enough to repair the coverage hole.

4. The two-dimensional wireless sensor network coverage hole repairing method according to claim 3, wherein in the step (1.1), the neighbor nodes capable of communicating within five hops of the node A are: a, three one-hop neighbor nodes in active communication meet the requirement that an angle formed between two adjacent one-hop neighbor nodes and a mobile node is close to or equal to 120 degrees, and A sends node information including node id to the three one-hop neighbor nodes and determines whether the three one-hop neighbor nodes are the mobile node or not;

the three one-hop neighbor nodes respectively forward node information, any one-hop neighbor node communicates to find two one-hop neighbor node forwarding node information and simultaneously forwards own node information, and the one-hop neighbor nodes and the two one-hop neighbor nodes of the one-hop neighbor nodes form a position relation close to or equal to 120 degrees pairwise; the two one-hop neighbor nodes respectively repeat the process steps of three one-hop neighbor node communication forwarding node information;

and after the node information of the A continuously sends the five-hop neighbor nodes, or meets the boundary node in the sending process, or meets other mobile nodes in the sending process, the node information is forwarded.

5. The two-dimensional wireless sensor network coverage hole repairing method according to claim 1, wherein when the moving path of the mobile node is selected in the step (3), whether the moving direction is correct or not is judged according to the signal strength of the path node id on the moving path sensed by the mobile node by using the known path node id in the return message, and the moving path is adjusted.

6. The two-dimensional wireless sensor network coverage hole repairing method according to claim 1, wherein in the step (4), the process that the mobile node calculates the relative position of the mobile node in the coverage hole and performs hole repairing is coordinate-free sequential surrounding type coverage hole repairing, including repairing the first mobile node and partially repairing the rest of the mobile nodes;

the first mobile node repair process is: forming an array of boundary nodes covering the loophole according to an adjacent sequence, wherein the first mobile node at least covers the intersection point of two boundary node induction ranges of any adjacent serial numbers of the array formed by the target loophole; the first mobile node is positioned on the perpendicular bisector of the connecting line of any two adjacent boundary nodes;

the partial repairing process of the rest mobile nodes is as follows: when any one of the other mobile nodes repairs the coverage hole, judging whether the induction range of the previous mobile node and the next boundary node with the sequence number has an intersection point or not;

when the induction range of the last mobile node and the next boundary node with the sequence number has no intersection point, any mobile node in the other mobile nodes at least covers the intersection point of the induction range of the next boundary node with the sequence number and the larger group number in the boundary nodes selected when the last mobile node in the target coverage loophole repairs the coverage loophole, and the intersection point is marked as a first intersection point; and covering the intersection point of the sensing ranges of the boundary nodes with larger group numbers in the two boundary nodes selected when the previous mobile node and the previous mobile node repair the coverage hole, and marking as a second intersection point; the mobile node is positioned on a perpendicular bisector of the first intersection point and the second intersection point;

when the induction range of the last mobile node and the next boundary node with the sequence number has an intersection point, any one of the other mobile nodes at least covers the intersection point of the induction ranges of the last mobile node and the next boundary node with the sequence number and is marked as a third intersection point; and covering the intersection point of the induction ranges of two adjacent boundary nodes with the sequence numbers of the two boundary nodes selected when the target coverage hole and the last mobile node repair the coverage hole, and marking as a fourth intersection point; the mobile node is located on a midperpendicular of the third and fourth intersection points.

7. The method for repairing the coverage hole of the two-dimensional wireless sensor network according to claim 1, wherein the criteria for the mobile node to successfully repair the coverage hole in the step 4) are as follows: the distances between all the mobile nodes which select to repair the coverage hole and the distance between the mobile nodes and the boundary nodes of the coverage hole are less than 2 sr.