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Wireless ad-hoc network comprises of numerous randomly and freely moving wireless devices that cooperatively form a network without any central administration or fixed infrastructure. A device can communicate with the other devices in the network that are in direct transmission range. In ad-hoc network routing protocols are classified into two types- Table driven (proactive) and On-Demand (reactive) routing protocols. The main purpose of table-driven routing schemes is to maintain the updated routing data about node’s connectivity within the network. The routing table maintains the latest information by periodically sending the messages to the neighbouring nodes. Cluster-head gateway switch routing (CGSR) (Thakur & Ganpati, 2015) and Dynamic Destination-Sequenced Distance-Vector Routing Protocol (DSDV) (Habib, Saleem, & Saqib, 2013) are the example of table-driven routing protocols. In on-demand protocols the overhead of maintaining updated routing information is reduced effectively. The routing information is accessed only when the device has data to send. For route discovery the node needs to broadcast packets which consume lots of bandwidth and energy. The efficiency of on-demand routing schemes is poor in large networks. Therefore, these protocols can be used in small network only. DSR, AODV are most popular example of on-demand protocols. (Habib, Saleem & Saqib, 2013). Nodes in ad-hoc networks have some crucial constraint, firstly the nodes are battery powered and have restricted capacity and secondly nodes deployed in the network are unattended therefore it is very complex to recharge or substitute them in the remote area (Rukpakavong, Guan, and Phillips, 2014). Hence, network lifetime is a key concern in mobile ad-hoc networks. Various power aware routing mechanism have been proposed and developed to preserve energy, prolonging the life span of its nodes and thus of the network itself. Various other metrics for preserving energy also considered viz. selecting shortest path from source to destination, remaining battery power, fair distribution of traffic load among the nodes and minimizing the total transmission power with a view to increase the network life span and link stability. Minimum battery cost routing (MBCR) (Singh, Woo & Raghavendra, 1998), min-max battery cost routing (MMBCR) (Sarkar & Majumder, 2014), maximum path lifetime routing (MPLR), power aware source routing (PSR) (Maleki, Dantu, and Pedram, 2002) and minimum drain rate (MDR) (Gomathi, Krishnamurthi, and Chbeir, 2006) algorithms takes power conservation as main objective. Most of the existing power aware methodologies consider only the minimum transmission cost and select the path which consume less power for communication that lead to the energy exhaustion of nodes on that path, hence affect network integrity and connectivity, therefore cause network partition.
In the worst scenario, the conventional routing protocols focuses only on the theoretical efficiency, neglecting the limited energy in wireless nodes. Some other power aware studies use residual energy to calculate the lifetime of nodes. The residual power of a node’s battery is dependent on the temperature of the node as well as on the output voltage.
These studies do not consider other environmental factors in which the node is operating such as temperature, ageing, charge cycles which greatly affects the lifetime of node. Therefore, inaccurate estimation of remaining capacity leads to the suboptimal path selection. A systematic method is proposed in this paper to diminish the undesirable effect. Under such dynamic circumstances, wireless devices are more at risk to failures caused by exterior environment actions and/or internal device problems than those in a guarded system. The unforeseen failure due to energy exhaustion restrict the node lifetime.
The goal of this work is to,
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Propose a new lifetime estimation model of a node for predicting the node lifetime according to current traffic condition considering the effect of varying temperature on residual battery capacity.
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Designing of power effective routing protocol that lead to increased network lifetime and performance.