  Electronic health monitoring is one of the major applications of wireless
body area networks (WBANs) that helps with early detection of any abnormal
physiological symptoms. In this paper, we propose and solve an optimization
problem that maximizes the energy efficiency (EE) of WBAN consisting of sensor
nodes (SNs) equipped with energy harvesting capabilities communicating with an
aggregator. We exploit the structure of the optimization problem to provide a
sub-optimal solution at a lower computational complexity and derive the
mathematical expressions of upper and lower bounds of the source rates of the
SN. The simulation results reveal that the optimal allocation of the source
rate to energy critical SNs improves the system performance of WBAN in terms of
energy efficiency during different everyday activities.
