Priority based IEEE 802.15.4 MAC by varying GTS to satisfy heterogeneous traffic in healthcare application

Abstract

This work presents the design of IEEE 802.15.4, the Medium Access Control protocol to ensure that medical data must be delivered in time, along with satisfying QoS requirements of Wireless Body Sensor Network based healthcare applications. Here, we propose the allocation of Guaranteed Time Slots (GTS) as per the varying rate of heterogeneous data traffic sensed by different sensor nodes ensuring energy efficiency, low latency, high throughput etc. Due to the sudden critical condition of the patient, the sensor node with an abrupt increase in data rate is assigned the highest priority and allocated dynamically more GTS. We have simulated different scenarios representing the normal and critical conditions of patients using Castalia 3.3 and OMNeT++. The temporal variation incorporates the movement associated with body which results to capture the fading arises due to the changing environment and movement of the nodes. This gives the practical variation associated with the nodes. We have compared among six different data traffic handling techniques: first where no nodes are allocated any GTS, second where all nodes are allocated fixed number of GTS and third where we propose dynamic GTS allocation as per the varying rate of data traffic. These three conditions are tested with Temporal and noTemporal variation. We have performed the simulation with 8 nodes and 11 nodes. The results show that in proposed technique, there is a significant reduction in energy consumption by $$\approx 20\%$$ by varyGTS vonfiguration. The average of varyGTS, Temporal and varyGTS, noTemporal packets received is $$\approx 76\%$$ in 8 nodes and $$\approx 66\%$$ by varyGTS, noTemporal in 11 nodes within the 240 ms delay permissible in healthcare application.