Priority-based medium access control for wireless body area networks with high-performance design

Abstract

The wireless body area network (WBAN) has attracted considerable attention. Two main problems exist in WBANs: 1) the quality of service (QoS) requirements and 2) the energy efficiency of data transmission. To solve the above problems, in this paper, we carefully design the sensor priority according to the importance degree, sampling rate, timeout condition, and remaining energy. Then, considering the priority of the node and the channel factors, a utility function is introduced to characterize the value of a node transmitting data frames in a specific time period. Next, we model the time slot allocation problem, where the objective is to maximize the total utility of the data transmission of all nodes in a specified period of time by adjusting the transmission time and the transmission duration of each node. Finally, according to the problem model, we propose a time slot allocation scheme based on a greedy strategy, which effectively reduces the time complexity of the direct solution to the problem. In this scheme, nodes with higher priority are arranged to transmit data frames in the time slots with better channel conditions. The experimental results show that the proposed scheme achieves substantial improvements in QoS and energy efficiency relative to the comparison schemes.