SmartBAN Downlink Performance Study: A Novel Transmission Framework for Reducing Delay and Energy Consumption

Abstract

The smart body area network (SmartBAN) is a recently proposed system for realizing low complexity and ultralow power body area network. In this paper, we present the first study on SmartBAN downlink delay and energy performances considering the emerging control/actuation applications in future e-health. A novel downlink transmission framework arising from our performance study is presented, which reduces the delay and energy consumption for downlink-dominated SmartBANs. In this paper, we first investigate the delay of the supplementary downlink mode (SDM) specified in the SmartBAN medium access control (MAC) protocol and propose an improved SDM (ISDM), showing that reordering the access periods in the SmartBAN MAC frame can effectively reduce the delay. To address the delay bottleneck in SDM and ISDM, we further propose limited-exhaustive (LEDM) and fully exhaustive (FEDM) downlink mechanisms. Then, based on SDM, ISDM, LEDM, and FEDM, energy-saving mechanisms in the SmartBAN downlink are discussed. Moreover, to critically evaluate the delay and energy-savings of LEDM and FEDM, we develop two embedded Markov chains that suit the SmartBAN beacon-enabled MAC. Finally, based on the above performances study, a novel downlink transmission framework that selects suitable transmission mechanism and access durations for delay-constraint SmartBAN applications is proposed. Extensive simulations show the effectiveness of our proposed mechanisms and transmission framework.