An adaptive MAC protocol for real-time and reliable communications in medical cyber-physical systems

摘要

With the increasing demands for high-quality health-care services, medical cyber-physical systems over wireless body sensor networks have emerged as a promising solution for vital life signals monitoring. These systems require the communication protocols to be both reliable and real-time in data transmissions. IEEE 802.15.4 can be regarded as the canonical protocols in this area owing to its low-power and low-cost features. However, it falls short of reliability and timeliness guarantees. To address this issue, we propose an adaptive MAC protocol based on IEEE 802.15.4, namely Ada-MAC. The proposed protocol combines schedule-based on time-triggered protocol and contention-based CSMA/CA mechanism. It can not only enable dynamic Guaranteed Time Slots allocation but also provide differentiated services for different nodes according to their data types. The proposed protocol is implemented on the OMNeT++ platform. Extensive simulations are conducted to evaluate the performance of Ada-MAC in comparison with the traditional IEEE 802.15.4 MAC. The results show the superiority of the proposed protocol in terms of reliability and timeliness.