Characterization of the On-Body Path Loss at 2.45 GHz and Energy Efficient WBAN Design for Dairy Cows

Wireless Body Area Networks (WBANs) provide promising applications in the healthcare monitoring of dairy cows. The characterization of the path loss between on-body nodes constitutes an important step in the deployment of a WBAN. In this paper, the path loss between nodes placed on the body of a dairy cow was determined at 2.45 GHz. FDTD simulations with two half-wavelength dipoles placed 20 mm above a cow model were performed using a 3-D electromagnetic solver. Measurements were conducted on a live cow to validate the simulation results. Excellent agreement between measurements and simulations was achieved and the obtained path loss values as a function of the transmitter-receiver separation were well fitted by a lognormal path loss model with a path loss exponent of 3.1 and a path loss at reference distance (10 cm) of 44 dB. As an application, the packet error rate and the energy efficiency of different WBAN topologies for dairy cows (i.e., single-hop, multi-hop, and cooperative networks) were investigated. The analysis results revealed that exploiting multi-hop and cooperative communication schemes decreases the packet error rate and increases the optimal payload packet size. The analysis results revealed that exploiting multi-hop and cooperative communication schemes increases the optimal payload packet size and improves the energy efficiency by 30%.