WO2016072838A1

WO2016072838A1 - A system and method for next hop selection in a wireless sensor network

Info

Publication number: WO2016072838A1
Application number: PCT/MY2015/050136
Authority: WO
Inventors: Harjinthar Singh PRETU; Su Jin Lim; Zeldi Suryady KAMALURRADAT; Ettikan Kandasamy Karuppiah; Mohamed Farid NOOR BATCHA
Original assignee: Mimos Berhad
Priority date: 2014-11-04
Filing date: 2015-10-30
Publication date: 2016-05-12
Also published as: MY177521A

Abstract

The system (100, 200) and method (300) of the present invention provides for next hop selection in a wireless sensor network. The system (100, 200) of the present invention comprising at least one sensor node (102) for sensing and transmitting sensing information through the wireless sensor network to a specified destination; and at least one sensor Gateway (104) for routing sensor information. The at least one sensor node (102) further comprising at least one Neighbor Discovery Module (210) for transmitting and receiving packets to discover neighbor nodes; at least one Measurement Module (212) for measuring network resources between sensor node and its neighboring nodes; at least one Prediction Module (216) for determining network resources between sensor node and its neighboring nodes without any measurement; and at least one Next Hop Selection Module (214) for selecting next hop route upon predicting most suitable neighboring node. The present invention speeds up the selection of cluster head in wireless sensor networks in order to reduce latency, reduce computation and to minimize excessive power consumption in transmission signals in a non-direct power supply nodes.

Description

A SYSTEM AND METHOD FOR NEXT HOP SELECTION IN A WIRELESS SENSOR

NETWORK

FIELD OF INVENTION

The present invention relates to a system and method for next hop selection in a wireless sensor network. In particular, the invention relates to systems and methods by speeding the selection of cluster head in wireless sensor networks in order to reduce latency, reduce computation and to minimize excessive power consumption in transmission signals in a non-direct power supply nodes.

BACKGROUND ART

In the process of a routing protocol, the next best hop is required to be selected for routing the data in a wireless network. There are several nodes in a network path leading to its destination, the Gateway. The best cluster head is to be selected from a group of nodes in a routing protocol in a wireless network wherein every node against n nodes is required to be checked which results in latency in converging, high volume of data exchange, high computation and excessive power usage for a sensor network. At present, existing cluster head selection mechanisms are based on signal strength, location measurement or power ratio. Mobility of the nodes caused topology reconstruction which might incur larger power consumption due to the computation cost while the memory consumption for routing protocol in large scale network also imposed a serious issue.

United States Patent Publication No. 201 10055424 A1 (US '424 Publication) entitled: Routing Method for Network and Sensing System relates to a routing method for a network, especially to a routing method for a wireless sensor network based on the multi-hop algorithm by considering the energies and covering areas. The invention as claimed in the US '424 Publication provides a full set of routing protocol for network and sensing system Further, in the US '424 Publication, cluster head selection from a group of nodes is based on calculation in each node wherein a first weighting value is calculated to select the cluster head. United States Patent No. 7,555,468 B2 (US '468 Patent) entitled Neural Network-based node mobility and network connectivity prediction for Mobile Ad Hoc Radio Network relates to an adaptable mobile communications networks and particularly, to an ad-hoc mobile network for adaptable wireless communications in an unstructured environment such as a tactical battlefield. The invention as claimed in the US '468 Patent utilizes prediction algorithm and implements ANN (Artificial Neural Network) prediction to estimate and predict link life between each node and its neighbors.. Further, in the US '468 Patent, self managed ad hoc communications network is employed, wherein the nodes manage node mobility within the network.

In a MDPI Journal on Sensor entitled: A Fuzzy Relevance-Based Cluster Head Selection Algorithm for Wireless Mobile Ad-Hoc Sensor Networks; by Chongdeuk Lee and Taegwon Jeong; published on 18 May 201 1 (Lee et. al.), a multi-hop network algorithm is implemented in a wireless sensor network by utilizing prediction algorithm. Fuzzy Relevance-based Cluster head selection Algorithm (FRCA) is utilized to select cluster head for clustering in wireless mobile sensor networks. Further, Lee et. al. discloses that the next hop selection is based on the shortest path wherein the distance cost between nodes is measured from the cluster head to member nodes.

SUMMARY OF INVENTION

The present invention relates to a system and method for next hop selection in a wireless sensor network which utilizes network metrics prediction with optimum link quality selection via neighbor discovery for message routing, measurement cost and power consumption. In particular, the invention relates to systems and methods which enable dynamic cluster head selection.

One aspect of the present invention provides a system (100, 200) for next hop selection in a wireless sensor network. The system comprising at least one sensor node (102) for sensing and transmitting sensing information through the wireless sensor network to a specified destination; and at least one sensor Gateway (104) for routing sensor information. The at least one sensor node (102) further comprising at least one Neighbor Discovery Module (210) for transmitting and receiving packets to discover neighbor nodes; at least one Measurement Module (212) for measuring network resources between sensor node and its neighboring nodes; at least one Prediction Module (216) for determining network resources between sensor node and its neighboring nodes without any measurement; and at least one Next Hop Selection Module (214) for selecting next hop route upon predicting most suitable neighboring node.

Another aspect of the invention provides that the at least one Neighbor Discovery Module (210) further comprising a routing table; said routing table is generated at each node and depicts the number of hops and cost per hop for each neighboring node. A further aspect of the invention provides that the at least one Prediction Module (216) for determining network resources between sensor node and its neighboring nodes without any measurement further having means for tabulating measured cost value in an arrangement of nodes to represent a network topology; removing nodes with only one neighbor in the arrangement of nodes; and forwarding resulting arrangement of nodes for generation of final arrangement of nodes.

Yet another aspect of the invention provides that the at least one Next Hop Selection Module (214) for selecting next hop route upon predicting most suitable neighboring node; the most suitable neighboring node is a node with a least predicted cost. Another aspect of the invention provides a method (300) for next hop selection in a wireless sensor network. The method (300) comprising steps of determining neighboring nodes by each sensor node (302); generating routing table at each node consisting of number of hops and cost per hop for each neighboring node by each sensor node (304); selecting sensor nodes of next hop and populating routing table generated at each node by each sensor node (306); measuring cost to reach neighboring nodes by each sensor node (308); tabulating measured cost value in an arrangement of nodes representing network topology (310); removing nodes with only one neighbor (312); performing completion of an arrangement of nodes on said arrangement by each sensor node (314); generating final arrangement of nodes by each sensor (316); and selecting node for next hop by routing packets to node with least predicted cost (318).

A further aspect of the invention provides that the step of performing completion of arrangement of nodes on said arrangement by each sensor node (314) further comprises steps of completing missing elements in said arrangement of nodes through interpolation (402); selecting lowest cost to fill the empty arrangement of nodes (404); splitting completed arrangement of nodes (406); and updating said arrangement of nodes matrix to reflect changes in the prediction by each sensor node (408). The present invention consists of features and a combination of parts hereinafter fully described and illustrated in the accompanying drawings, it being understood that various changes in the details may be made without departing from the scope of the invention or sacrificing any of the advantages of the present invention.

BRIEF DESCRIPTION OF ACCOMPANYING DRAWINGS

To further clarify various aspects of some embodiments of the present invention, a more particular description of the invention will be rendered by references to specific embodiments thereof, which are illustrated in the appended drawings. It is appreciated that these drawings depict only typical embodiments of the invention and are therefore not to be considered limiting of its scope. The invention will be described and explained with additional specificity and detail through the accompanying drawings in which: FIG. 1 .0 illustrates the general architecture of a wireless sensor network.

FIG. 2.0 illustrates the internal components of a sensor node of the present invention.

FIG. 3.0 is a flowchart illustrating the methodology of the present invention.

FIG. 4.0 is a flowchart illustrating the steps for performing completion of arrangement of nodes by each sensor node.

FIG. 5.0 illustrates the topology of a network diagram.

FIG. 6.0 illustrates the topology of a network diagram together with the mesh prediction.

FIG. 7.0 illustrates a diagram which shows the routing table with the nearest hop to each of the node.

FIG. 8.0 illustrates a diagram which shows multiple nodes that are the next hop for node 2.

FIG. 9.0 illustrates a diagram which shows the step to perform matrix completion algorithm for adaptive next hop selection.

FIGs. 10.0- 18.0 illustrate a diagram which shows the post deployment phase.

Tables 1 .0, 2.0, 3.0 and 4.0 provide the tabulation of the matrix completion algorithm. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

The present invention provides a system and method for next hop selection in a wireless sensor network. In particular, the present invention speed up the selection of cluster head in wireless sensor networks to reduce latency, reduce computation and to minimize excessive power consumption in transmission signals in a non-direct power supply nodes. Hereinafter, this specification will describe the present invention according to the preferred embodiments. It is to be understood that limiting the description to the preferred embodiments of the invention is merely to facilitate discussion of the present invention and it is envisioned without departing from the scope of the appended claims.

FIG. 1 .0 illustrates the general architecture of a wireless sensor network. As illustrated in FIG. 1 .0, a wireless sensor network (100) consists of a collection of sensor nodes (102) and sensor Gateway (104). The sensor nodes (102) consist of processing capability which contains multiple types of memory and communication units with various sensors and actuators. The sensor nodes communicate wirelessly in the network and self- organize upon deployment in an ad-hoc manner. The sensor nodes (102) sense and transmit sensing information through the wireless sensor network to a specified destination; and the sensor Gateway (104) routes sensor information.

Referring to FIG. 2.0, the internal components of a sensor node of the present invention is illustrated. The sensor node of the present invention further comprising a Neighbor Discovery Module (210) for transmitting and receiving packets to discover neighbor nodes; a Measurement Module (212) for measuring network resources between sensor node and its neighboring nodes; a Prediction Module (216) for determining network resources between sensor node and its neighboring nodes without any measurement; and a Next Hop Selection Module (214) for selecting next hop route upon predicting most suitable neighboring node. The most suitable neighboring node is a node with a least predicted cost. The Neighbor Discovery Module (210) further comprising a routing table; said routing table is generated at each node and depicts the number of hops and cost per hop for each neighboring node. The Prediction Module (216) further tabulates measured cost value in an arrangement of nodes to represent a network topology; removing nodes with only one neighbor in the arrangement of nodes; and forwarding resulting arrangement of nodes for generation of final arrangement of nodes. FIG. 5.0 illustrates the topology of a network diagram. In a routing process, the next best hop is to be selected for routing. As illustrated in FIG. 5.0, in order to reach the Gateway (G), each node is required to select the best path. FIG. 3.0 is a flowchart illustrating the steps of the methodology of the present invention and FIG. 4.0 is a flowchart illustrating the steps for performing completion of arrangement of nodes by each sensor node. As illustrated in FIG. 3.0, the method (300) for next hop selection in a wireless sensor network is initiated by determining neighboring nodes by each sensor node (302). In a wireless sensor node, nodes at one hop away from the source node are selected as neighboring node. The same procedure applies at other nodes. A routing table is generated at each node consisting of number of hops and cost per hop for each neighboring node by each sensor node (304). Thereafter, sensor nodes of next hop are selected and the generated routing table is populated at each node by each sensor node (306). Each node randomly measures the cost to reach neighboring nodes by each sensor node (308) and each node tabulates the measured cost value in an arrangement of nodes representing the network topology (310). Nodes with only one neighbor are removed from the arrangement of nodes as there is no selection of choice (312). Subsequently, each sensor node performs completion of an arrangement of nodes on said arrangement (314). As illustrated in FIG. 4.0, in order to perform completion of arrangement of nodes by each sensor node, missing elements in said arrangement of nodes are completed through interpolation (402). Thereafter, the lowest cost is selected to fill the empty arrangement of nodes (404). Completed arrangement of nodes are split (406) and the arrangement of nodes matrix are updated to reflect the changes in the prediction by each sensor node (408). Upon performing completion of nodes, the final arrangement of nodes are generated by each sensor (316) and the node for the next hop is selected by routing packets to node with least predicted cost (318). The arrangement of nodes is in matrix form.

FIG. 6.0 illustrates the topology of a network diagram together with the mesh prediction. As illustrated in FIG. 6.0, assumptions are made whereby node with only one neighbor at initial stage is assumed to be the leave node which will be eliminated in an arrangement of nodes. The arrangement of nodes between the nodes in the network is correlated. The link with the highest factor is selected. For example, as provided in the mesh prediction of Table 1 of FIG. 6, node 6 is the cluster head for node 2 as 2 is >6. Referring to FIG. 7.0, the routing table with the nearest hop to each of the node is illustrated. Routing table is constructed at each node to select the node at one hop away as their neighbor. In FIG.8.0, multiple nodes that are the next hop for node 2 are shown as 1 , 2, 3 and 4 in the diagrams that correspond to the routing table. FIG. 9.0 illustrates a diagram which shows the step to perform matrix completion algorithm for adaptive next hop selection wherein the possible next hop routes with the lowest cost factor is grayed. Neighboring nodes has only one hop selection. FIGs. 10.0- 18.0 illustrate a diagram which shows the post deployment phase. For examples, as illustrated in FIG. 10.0, node 1 is a leaf node which is connected to node 2 initially and remains unchanged. Node 2 is the cluster head for node 1 .

Tables 1 .0, 2.0, 3.0 and 4.0 provide the tabulation of the matrix completion algorithm. As provided in Table 1 .0, nodes with only one neighboring hop are removed as there is no need for calculation. Further, as provided in Table 2.0, missing elements cannot be handled by Singular Value Decomposition (SVD). SVD is used for initialization to decompose distance matrix, D into two smaller matrices X, Y. Since missing elements cannot be handled by SVD, row-column interpolation is performed wherein

Cost_in,_x). The present invention provides a system and method which overcomes the current problem by speeding the selection of cluster head in wireless sensor networks in order to reduce latency, reduce computation and to minimize excessive power consumption in transmission signals in a non-direct power supply nodes. The prediction protocol technique is introduced in the present invention wherein a network metrics prediction with optimum link quality selection via neighbor discovery for message routing, measurement cost and power consumption enables dynamic cluster head selection. As described above, each node will select its optimum neighbor to transmit the message to the destination node (i.e. the Gateway). Unless the context requires otherwise or specifically stated to the contrary, integers, steps or elements of the invention recited herein as singular integers, steps or elements clearly encompass both singular and plural forms of the recited integers, steps or elements. Throughout this specification, unless the context requires otherwise, the word "comprise", or variations such as "comprises" or "comprising", will be understood to imply the inclusion of a stated step or element or integer or group of steps or elements or integers, but not the exclusion of any other step or element or integer or group of steps, elements or integers. Thus, in the context of this specification, the term "comprising" is used in an inclusive sense and thus should be understood as meaning "including principally, but not necessarily solely".

It will be appreciated that the foregoing description has been given by way of illustrative example of the invention and that all such modifications and variations thereto as would be apparent to persons of skill in the art are deemed to fall within the broad scope and ambit of the invention as herein set forth.

Claims

1 . A system (100, 200) for next hop selection in a wireless sensor network comprising:

at least one sensor node (102) for sensing and transmitting sensing information through the wireless sensor network to a specified destination; and

at least one sensor Gateway (104) for routing sensor information characterized in that

the at least one sensor node (102) further comprising:

at least one Neighbor Discovery Module (210) for transmitting and receiving packets to discover neighbor nodes;

at least one Measurement Module (212) for measuring network resources between sensor node and its neighboring nodes;

at least one Prediction Module (216) for determining network resources between sensor node and its neighboring nodes without any measurement; and

at least one Next Hop Selection Module (214) for selecting next hop route upon predicting most suitable neighboring node.

2. A system (200) according to Claim 1 , wherein the at least one Neighbor Discovery Module (210) further comprising a routing table; said routing table is generated at each node and depicts the number of hops and cost per hop for each neighboring node.

3. A system (200) according to Claim 1 , wherein the at least one Prediction Module (216) for determining network resources between sensor node and its neighboring nodes without any measurement further having means for:

tabulating measured cost value in an arrangement of nodes to represent a network topology;

removing nodes with only one neighbor in the arrangement of nodes; and forwarding resulting arrangement of nodes for generation of final arrangement of nodes. A system (200) according to Claim 1 , wherein the most suitable neighboring node is a node with a least predicted cost.

A method (300) for next hop selection in a wireless sensor network comprising steps of:

determining neighboring nodes by each sensor node (302);

generating routing table at each node consisting of number of hops and cost per hop for each neighboring node by each sensor node (304);

selecting sensor nodes of next hop and populating routing table generated at each node by each sensor node (306);

measuring cost to reach neighboring nodes by each sensor node (308); tabulating measured cost value in an arrangement of nodes representing network topology (310);

removing nodes with only one neighbor (312);

performing completion of an arrangement of nodes on said arrangement by each sensor node (314);

generating final arrangement of nodes by each sensor (316); and selecting node for next hop by routing packets to node with least predicted cost (318).

A method (300) according to Claim 5, wherein performing completion of arrangement of nodes on said arrangement by each sensor node (314) further comprises steps of:

completing missing elements in said arrangement of nodes through interpolation (402);

selecting lowest cost to fill the empty arrangement of nodes (404);

splitting completed arrangement of nodes (406); and

updating said arrangement of nodes to reflect changes in the prediction by each sensor node (408).