Energy consumption analysis of modulation schemes in IEEE 802.15.6-based wireless body area networks

Abstract

Selection of the most energy-efficient modulation scheme is vital for wireless body area networks (WBANs) for improving the network lifetime. In this paper, we investigate the performance of various modulation schemes specified by IEEE 802.15.6 WBAN standard, in terms of energy consumed for successfully transferring one packet from the sensor node to the hub. Assuming a contention-free MAC protocol, we present an analytical model for computing the energy consumption for a given modulation scheme both for uncoded transmission as well as transmission using Bose-Chaudhuri-Hocquengham (BCH) codes; the coding scheme specified by IEEE 802.15.6 for WBAN. The following communication scenarios specific to a WBAN are considered: (i) in-body communication between invasive devices and hub and (ii) on-body communication among non-invasive devices and hub with line-of-sight (LOS) and non-LOS (NLOS) channels. The results show that the use of higher order differential phase shift keying (D8PSK)-based modulation schemes results in significant reduction of total energy consumption. When BCH codes with various code rate specifications are used, total energy consumption remains lower for the higher order modulation schemes. The energy consumption is further reduced when non-coherent frequency shift keying (NC-MFSK) is employed as an alternate modulation scheme instead of differential PSK schemes.