System Loss Model for Body-to-Body Networks in Indoor and Outdoor Environments

A system loss model for body-to-body networks in indoor and outdoor environments is proposed in this paper, based on measurements taken at 2.45 GHz. The influence of the type of environment, antenna visibility and user mobility on model parameters has been investigated. A significant impact of mutual antennas' placement and their visibility is shown. The proposed model fits well to empirical data, with the average root mean square error being 2.1 dB and the coefficient of determination being above 0.6 in the majority of cases. For designing purposes in generalised cases, it is recommended that the system loss exponent is set to 1.5, and the system loss at the reference distance is equal to 55.9 dB.

I. Introduction

A deep understanding of radio channel properties is extremely important when designing any kind of wireless system, including Body Area Networks (BANs), which are the body centric wireless communications where at least one of the communication devices is attached to the human body [1]. There may be many types of BANs, when taking the type of radio link into account. In this paper, a body-to-body (B2B) case is considered, in which communications take place between wearable devices on two independently moving users, and antennas on both sides of the radio link are influenced by the presence of users' bodies [2].