Optimal Transmit Power and Packet Size in Wireless Sensor Networks in Shadowed Channel

Abstract- This paper investigates the effects of shadowing on the optimal transmit power required to sustain the network connectivity while maintaining a predefined maximum tolerable Bit Error Rate (BER) in a Wireless Sensor Networks (WSN). Optimization of transmit power is of great importance in WSN since sensor nodes are battery driven and optimization helps to increase battery life by reducing inter node interference significantly. An infinite Automatic Repeat Request (ARQ) model has been considered to assess the impact of shadowing and other network conditions on energy requirement for successful packet transmission in WSN. We also find the optimal packet length based on energy efficiency. Effects of shadowing on optimal packet size and energy efficiency in packetized data transmission are also investigated. Further energy consumption is minimized considering a variable packet length based transmission. Use of optimal packet size shows a significant reduction in energy spending