16 Satyanarayana Chanagala, Zafar Jawed Khan, Sarath Kumar Annavarapu, K.Madhu Sudhana Rao, M.Srinivasa Sesha Sai International Journal of Innovations & Advancement in Computer Science IJIACS ISSN 2347 – 8616 Volume 6, Issue 9 September 2017 A Rate Capacity aware approach to maximize the Lifetime of Wireless Sensor Network Satyanarayana Chanagala KKR & KSR Institute of Technology and Sciences, Guntur (A.P) Zafar Jawed Khan Rajiv Gandhi College of Engineering, Research, and Technology, Chandrapur (MH) Sarath Kumar Annavarapu, K.Madhu Sudhana Rao, M.Srinivasa Sesha Sai KKR & KSR Institute of Technology and Sciences, Guntur (A.P) ABSTRACT: In recent times the lifetime of Wireless Sensor Networks (WSN) has attracted many researchers. As a result, many power aware algorithms have been designed with different strategies. These strategies are based on time scheduling techniques, Delay bound constraints, Data adoption techniques, Data aggregation, Mobile sinks, Query based approach, and Management of spare nodes depending on the levels of their residual energies. All the mentioned approaches are implemented simulators. Results obtained in terms of life extensions with simulators and practical deployments have shown major deviations. Lifetime extensions obtained with practical deployments is far less than that obtained with simulations, using the same strategies. Investigations have shown that a lower lifetime with practical deployment is due to premature exhaustion of the sensor node’s battery. The three important reasons for the early death of the battery is found to be an improper selection of sampling interval, the effect of the environment of sensor field, and transmitting the sensed data with improper transmission power level. These sensor node parameters have a direct impact on the Rate Capacity and Recovery effect, which are electro-chemistry related characteristics of the battery. In this paper, a practical approach is adopted to understand the impact of different transmission power levels on the lifetime of the sensor node and hence the wireless sensor network. In the process, an optimum value of the transmission power level of data packets is found which mitigates the Rate Capacity of the battery. With the optimized transmission power level, around23% improvement in the lifetime of the sensor node has been achieved. Keywords: Lifetime, Transmission power level, Rate capacity I.INTRODUCTION The chief constraint of a sensor node in WSN is its limited energy supply. When the sensor nodes are deployed in hazardous environments and impenetrable terrains, it is not possible to replace the exhausted batteries. Thus the lifetime of the sensor node depends on the lifetime of the battery. Therefore it is important to develop techniques to prolong the lifetime of the battery. The electrochemistry of the battery plays a major role in its lifetime. Apart from that, the sensor field environment also plays an important role in its longevity. Rate capacity and Recovery effect of the battery are studied with respect to the load. These two factors are related to sampling interval and transmission power level of the sensor node. When the current is drawn from the battery, the positive ions are consumed at electrolyte anode interface. And further, positive ions are supplied by the anode of the battery. If the current drawn is low to moderate, the inactive regions are uniformly distributed throughout the cathode. However, when the current drawn is higher, then the cathode outer surface gets covered with inactive sites. This results in unavailability of internal active sites. As a consequence, the battery gets drained out of most of its energy unused. Hence, an arbitrary selection of transmission power level of data packets may result in premature exhaustion of the battery. Therefore, there is a need to find an optimum transmission power level for the data transmitted so that the Rate capacity effect can be mitigated. The typical architecture of the WSN is as shown in Fig 1.