Abstract
The aging population and the high quality of life expectations in our society lead to the need of more efficient and affordable healthcare solutions. For this reason, this paper aims for the optimization of Medium Access Control (MAC) protocols for biomedical wireless sensor networks or wireless Body Sensor Networks (BSNs). The hereby presented schemes always have in mind the efficient management of channel resources and the overall minimization of sensors’ energy consumption in order to prolong sensors’ battery life. The fact that the IEEE 802.15.4 MAC does not fully satisfy BSN requirements highlights the need for the design of new scalable MAC solutions, which guarantee low-power consumption to the maximum number of body sensors in high density areas (i.e., in saturation conditions). In order to emphasize IEEE 802.15.4 MAC limitations, this article presents a detailed overview of this de facto standard for Wireless Sensor Networks (WSNs), which serves as a link for the introduction and initial description of our here proposed Distributed Queuing (DQ) MAC protocol for BSN scenarios. Within this framework, an extensive DQ MAC energy-consumption analysis in saturation conditions is presented to be able to evaluate its performance in relation to IEEE 802.5.4 MAC in highly dense BSNs. The obtained results show that the proposed scheme outperforms IEEE 802.15.4 MAC in average energy consumption per information bit, thus providing a better overall performance that scales appropriately to BSNs under high traffic conditions. These benefits are obtained by eliminating back-off periods and collisions in data packet transmissions, while minimizing the control overhead.
Highlights
The release of IEEE 802.15.4 for Low Rate Wireless Personal Area Networks (LR-WPAN) [1]represents a milestone in Wireless Sensor Networks (WSNs), and is the current standard of choice for most Body Sensor Networks (BSNs) studied scenarios
Analytical results of average energy consumption per information bit are presented in order to get a measure of the obtainable benefits of using this Distributed Queuing (DQ) medium access control (MAC) proposal compared to IEEE 802.15.4 MAC in extensive healthcare scenarios with a raising number of body sensors in the same area
When evaluating Distributed Queuing Medium Access Protocol (DQ MAC) protocol energy consumption per information bit in the same saturation conditions, we observed that DQ MAC energy efficiency is independent of the number of body sensors in the BSN, similar to the previous throughput analysis That is, because of the inherent behavior of DQ MAC of eliminating back-off periods and collisions in data transmissions by means of the distributed queuing system
Summary
The release of IEEE 802.15.4 for Low Rate Wireless Personal Area Networks (LR-WPAN) [1]. This functionality targets very low latency applications, but does not scale properly to highly dense BSNs (i.e., saturation conditions), since the number of dedicated slots would not be sufficient to accommodate more than seven body sensors at a time In such conditions, it is better to use the contention access mode, where the sparse data is statistically multiplexed. The model and analysis are similar in form to Bianchi’s [6], but here the key approximation in their model is the independence of the carrier sensing probability, which determines when nodes become active to listen to the channel Both analytical models in [7] and [8] show how the gross saturation throughput, expressed as the number of occupied slots for successful packet transmissions of size L (ignoring protocol over-head), drastically decreases as the number of sensors in the network increases. Analytical results of average energy consumption per information bit are presented in order to get a measure of the obtainable benefits of using this DQ MAC proposal compared to IEEE 802.15.4 MAC in extensive healthcare scenarios with a raising number of body sensors in the same area (i.e., high density area)
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
