Method for power consumption reduction in a wireless linear network
The present disclosure relates to a clustering approach for sensor nodes of a wireless sensor network. This clustering approach, equal distance different members, balances the power burden amongst sensor nodes by deriving an optimal number of sensor nodes at each segment of a length. To this end, the present disclosure describes a linear wireless sensor network wherein the distance between adjacent cluster heads is equal while the number of and distance between sensor nodes in each cluster is different. A power consumption model is derived to aid in the determination of the optimal number of sensor nodes within each cluster. Following evaluation of the cluster approach in comparison with previously described approaches, the present disclosure is observed to improve network longevity and reduce power consumption by deliberately increasing the density of sensor nodes nearest a base station.
1. A method for reduction of power consumption and placement of transmitting nodes of a wireless network transmitting with a rotating cluster head strategy, comprising:
positioning a plurality of clusters, each cluster having a cluster head and a plurality of sensor nodes, of one or more transmitting nodes along a geometrically-linear path, each cluster of the plurality of clusters and each one of the one or more transmitting nodes of the plurality of clusters being aligned with the geometrically-linear path, wherein a distance between each cluster of the plurality of clusters is equal;
determining power consumption of a distal cluster of one or more transmitting nodes, positioned furthest from a proximal cluster of one or more transmitting nodes, wherein the power consumption of the distal cluster is based upon state variables of the one or more transmitting nodes;
determining a number of transmitting nodes in the distal cluster of one or more transmitting nodes based upon the power consumption of the distal cluster of one or more transmitting nodes, the number of transmitting nodes being determined to maximize lifetime;
determining power consumption of a subsequent cluster of one or more transmitting nodes, wherein the power consumption of the subsequent cluster of one or more transmitting nodes is based upon state variables of the one or more transmitting nodes; and
determining a number of transmitting nodes in the subsequent cluster of one or more transmitting nodes based upon the determined power consumption of the subsequent cluster of one or more transmitting nodes, the number of transmitting nodes being determined to maximize lifetime,
wherein lifetime is based upon initial capacity of a transmitting node battery, number of transmitting nodes in each cluster of the plurality of clusters, and power consumption of a head transmitting node of each cluster of the plurality of clusters.
2. The method of claim 1 , further comprising assigning equal distances between the one or more transmitting nodes within each cluster of the plurality of clusters.
3. The method of claim 1 , further comprising assigning each of the one or more transmitting nodes to one of the plurality of clusters, wherein each of the one or more transmitting nodes communicates only within an assigned cluster of the plurality of clusters.
4. The method of claim 1 , further comprising selecting a first head transmitting node of each cluster of the plurality of clusters.
5. The method of claim 4 , wherein the first head transmitting node of each of the plurality of clusters is configured to receive intra-cluster and inter-cluster transmissions and forward inter-cluster transmissions and the first head is one of the cluster heads.
6. The method of claim 4 , further comprising selecting a subsequent head transmitting node of each of the plurality of clusters, the subsequent head transmitting node selected when an energy level of the first head transmitting node reaches a predetermined level.
7. The method of claim 6 , wherein the predetermined level of the energy level comprises a minimum energy level required for transmission.
8. The method of claim 1 , wherein the number of transmitting nodes of a proximal cluster of the plurality of clusters is greater than or equal to the number of transmitting nodes of an adjacent, distal cluster of the plurality of clusters.
9. The method of claim 1 , wherein the state variables of the transmitting nodes include energy capacity, transmission power, and transmission range.
10. The method of claim 1 , wherein the number of transmitting nodes of each cluster of the plurality of clusters is bounded by an inequality expressed as
1
4
+
2
(
P
R
+
f
)
(
P
T
+
P
R
)
-
1
2
≤
k
*
≤
1
4
+
2
(
P
R
+
f
)
(
P
T
+
P
R
)
+
1
2
,
where k * is the number of transmitting nodes of each cluster, P T is transmission power, P R is receiving power, and f i is the power consumption of the head transmitting node of each cluster.