On the energy utilization for WSN based on BPSK over the Generalized-K shadowed fading channel

Abstract

Energy is a scarce resource in the battery-powered nodes of wireless sensor networks (WSNs). In this paper the energy utilization for WSN based on BPSK communications has been investigated over the Generalized-K shadowed fading channel. A comprehensive analysis is reported based on the various important performance metrics like: amount of fading, average bit error probability, outage probability and energy utilized per bit (EUB). Simulation results reveal that composite use of shadowing and fading degrade energy levels to a considerable extent and hence contribute in downsizing the network life-span. We have derived the EUB metric and performed its evaluation with respect to optimal transmit energy levels by varying fading and shadowing severity parameters. We also considered the impact of varying transmit energy levels on the outage probability and hence on transmit and EUB levels. Although, embedding of training sequences and re-transmissions do help in enhancing effective synchronization and improved reliability, but this is done at a cost of higher energy utilization. Under the given set of assumptions, it is observed that an decrease in fading by about 11 %, improves the EUB by about 7 %. With increase in outage probability by about 10 %, EUB improves by about 3 %. An increase in SNR by 6 % improves the EUB levels by about 7 %. The investigations reported in this paper may enable designers to optionally choose suitable parameters to make WSN communications energy-efficient.