Optimizing Transmission Power for Uplink Data in Cell-Free Wireless Body Area Networks

Wireless body area networks (WBANs) have recently become a topic of interest due to their large number of applications and the rapid development of individual gadgets and devices for medical purposes. The model in this study, called a "cell-free WBANs" scheme, is developed on the basis of a cell-free multiple-input multiple-output (MIMO) system where a lot of access points (APs) serve a number of sensors simultaneously. A new system model where the sensors are distributed around the body and communicate directly with APs rather than through a coordinator is proposed. The interference due to simultaneous signal transmission from multiple sensors is taken into consideration, and the transmission power control algorithm for uplink data is developed to enhance the spectrum efficiency of the system. According to simulation results, in all considered scenarios, the proposed system’s performance is considerably improved in comparison with the small-cell model.