CA-MAC: A Hybrid context-aware MAC protocol for wireless body area networks

Reliability and energy efficiency enhancement in wireless body area networks for e-health

“…`However, due to the unknown exact time of the occurrences of the deep fade, re-transmitted packets will still suffer from the same deep fade problems as the original packets and therefore will not guarantee successful packets delivery, which will still be an issue at the expense of power consumption. Yan and Liu in [7] proposed a hybrid superframe based MAC protocol (CA-MAC) which comprises three parts: the beacon frame, the contention-based period that adopts the slotted CSMA/CA and which changes dynamically according to the level of fading in the channel, and the third part is the contention free period, which follows the TDMA mechanism. CA-MAC allocates transmission bandwidth, according to the traffic context and the channel status respectively.…”

Context awareness in WBANs: a survey on medical and non-medical applications

“…The so-called CA-MAC protocol was introduced in [6] to satisfy different traffic loads and to address time-varying channel conditions caused by frequent body movements. A hybrid of contention and TDMA-based approaches was used.…”

A Review of Protocol Implementations and Energy Efficient Cross-Layer Design for Wireless Body Area Networks

“…Steady state monitoring, for example EEG or blood glucose transmissions, could yield channel priority to heart rate and ECG sensor data which depending on the criticality of the patient, could be classified as high priority. Liu et al [48] presented Context Aware MAC (CA-MAC) that is able to adopt different transmission strategies depending on the variation of patient activity, vital life signs, or environment status. The protocol is designed around hybrid frame structure , channel aware adjustment of access mechanisms , and traffic aware adjustment of transmission priority .…”

“…The focus on this main challenge is likely to remain a key area of ongoing research due to the limitations of energy supply and longevity requirements especially for embedded nodes. Context aware protocols that differentiate between steady state and emergency traffic provide an interesting insight but further research is needed to move this area forward form the modeling/simulation arena to real life practical applications [48,50]. …”