Power control and localization of wireless body area networks using semidefinite programming

Wireless Body Area Network (WBAN) is a promising solution for Healthcare applications. However, how to mitigate the interference between WBANs is still challenging. In this paper, we propose a new method to mitigate the interference between WBANs using geometric programming (GP), which is a special optimization that can be transformed to convex optimization. To make sure that all receivers in WBANs can receive the signals sent from their pairwise transmitters, we require that the signal to interference and noise ratio (SINR) for each WBAN must be more than a given threshold. Then we can optimize the overall transmission power to save energy. We also propose to use convex optimization to solve location problem of WBANs based on their received signal strength indicators (RSSI). We set three WBANs to be anchor nodes with known locations, calculate the approximate distance between the transmitters, and then solve the convex problem to get the location for all other WBANs. The effectiveness of the proposed methods has been demonstrated through numerical simulations.