On Energy Level Performance of Adaptive Power Based WSN in Presence of Fading

We propose an adaptive power based transmission scheme for WSN (Wireless Sensor Networks) where transmit power is adapted depending on node density and channel conditions so as to maintain a desired level of signal detection probability at a receiving node as demanded by sensing range. In existing Fixed Transmit Power Scheme (FTPS), detection probability degrades with decrease in node spatial density leading to reduction in sensing range. We investigate the performance of the proposed Adaptive Transmit Power Scheme (ATPS) for a square grid WSN under multipath fading. Further energy consumption for an optimal packet length which yields highest energy efficiency is evaluated for both fixed and proposed adaptive power based schemes. Impact of node density, packet length and Rician fading on energy efficiency for both the ATPS and FTPS scheme is also shown.