Mitigation of mutual interference in IEEE 802.15.4-based wireless body sensor networks deployed in e-health monitoring systems

One of the main issues experienced in wireless body sensor networks (WBSNs) is the destructive impacts of "mutual interference" caused by neighboring WBSNs on each other's performance. Research communities have proposed several approaches to mitigate the impacts of mutual interference on the reliability of data transmission and sensor's energy consumption. However, the proposed approaches came with a number of limitations, such as significant modification of the standard protocol or imposing a high level of complexity. In this paper, a range of schemes are proposed, and their performances are evaluated in the presence of mutual interference experienced in a dynamic environment.More specifically, we consider a situation where a large number of people (each individual covered with a number of sensors to fetch the human vital sign) are gathered at a sport centre to enjoy an event. In such a dynamic environment, people would highly likely experience mutual interference which would destructively impact on WBSN's performances and eventually would result in an unreliable medical outcome. A simulation study is conducted in which a set of schemes proposed that indicates a gradual improvement of WBSN's performances in terms of reliability of data transmission and sensor's energy consumption. Our obtained results show that the frequency-adaptation strategy combined with phase-adaptation approach significantly improves the performance of WBSNs in the presence of mutual interference in a dynamic environment. Moreover, an experimental study is carried out to examine the feasibility of implementing the predominant scheme on real-world sensor devices and to further support the outcome of the simulation study.