Effects of Rayleigh Fading on Energy Level Performance of Adaptive Power Based WSN

Abstract

In this paper we propose an adaptive power based transmission scheme for WSN where transmit power is adapted depending on node density and channel condition so as to maintain the detection probability at a given level as demanded by sensing range. The sensing range as determined by detection probability depends on the nature of the propagation path, transmit power etc. In fixed transmit power scheme detection probability degrades with decrease in node spatial density. However it is important to keep the detection probability at a particular level considering the sensing range as poor detection probability results degradation in performance of the system. The impact of Rayleigh fading on detection probability and Bit Error Rate (BER) are investigated for a square grid sensor network. Energy consumption of fixed and adaptive transmit power scheme is analyzed for a given packet size. Further energy consumption for an optimal packet length which yields highest energy efficiency is evaluated for both fixed and proposed adaptive power based schemes.

Keywords

• Sensing range
• Wireless sensor networks (WSNs)
• Rayleigh fading
• Optimal packet size
• Detection probability