Abstract-The Overlapping Layers (OL) scheme proposed in our previous work provides a solution to balance the load of cluster heads at different layers in the PMRC-based wireless sensor networks. However, in the OL scheme, the layer boundary and the overlap range are static through the network lifetime. The network lifetime is still limited by some nodes which have only one candidate cluster head. To overcome this limitation, in this paper, we propose the Minimum Overlapping Layers (MOL) scheme with gradually changed layer boundary through network lifetime and its variant, the MOL with Initial Overlap (MOLIO) scheme. The simulation results of the OL, MOL, and MOLIO schemes show that the MOL scheme significantly prolongs the network lifetime than the OL scheme for most transmission ranges and the MOLIO scheme achieves better results than the MOL scheme at larger transmission ranges. Index Terms-Wireless sensor networks, overlapping layers, PMRC I. INTRODUCTION Due to the benefits of low cost, rapid deployment, selforganization capability and cooperative data processing, wireless sensor networks (WSNs) have been proposed as a practical solution for a wide range of applications [1], such as military surveillance and habitat monitoring, etc. Since the power supply for each sensor node is usually extremely limited, energy efficiency is the primary challenge of WSNs. Previous research shows that clustered structure [3] and multi-hop routing [1] [2] achieve better energy efficiency for large scale wireless sensor networks. In [8], a highly scalable network architecture, named as Progressive Multi-hop Rotational Clustered (PMRC) structure is proposed for constructing large scale WSNs. In the PMRC structure, sensor nodes are partitioned into layers according to their distance to the sink node. A cluster is composed of nodes located in the same layer and cluster head in the upper layer closer to the sink node. The cluster head is responsible for forwarding data to its upstream layer. As traffic load is concentrated on the cluster heads closer to the sink node, these cluster heads will deplete their power faster, which limit the lifetime of the whole network. This is referred as the bottleneck problem of the PMRC-based WSN. In the literature, several schemes have been proposed to solve the bottleneck problem in WSNs. In [6] , an Unequal Clustering (UCS) modeling is proposed to balance energy consumption of cluster heads in multi-hop WSNs. This work is focused on a heterogeneous network where cluster heads
As introduced in Section 1, in MOL-enabled REF PMRC-based WSNs, the layer boundary between neighbor layers is dynamically changed during network lifetime.
Minimum Overlapping Layers and Its Variant for Prolonging Network Lifetime in PMRC-Based Wireless Sensor Networks
2009 6th IEEE Consumer Communications and Networking Conference
2009 6th IEEE Consumer Communications and Networking Conference
Computer Science