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Wireless body sensor networks (WBSN) are a particular type of wireless sensor networks (WSN)
that are becoming an important topic in the technological research community. Advances in the
reduction of the power consumption and cost of these networks have led to solutions mature enough
for their use in a broad range of applications such as sportsman or health monitoring.
The development of those applications has been stimulated by the finalization of the IEEE 802.15.4
standard, which defines the medium access control (MAC) and physical layer (PHY) for low-rate
wireless personal area networks (LR-WPAN). One of the MAC schemes proposed is slotted Carrier
Sense Multiple Access with Collision Avoidance (CSMA/CA). This project analyzes the performance of
this MAC, based on a state-of-the-art analytical model for a star topology, which captures the behavior
of the MAC using two Markov chain models; the per-node state model and the channel state model.
More importantly, we extend this model to include acknowledged traffic. The impact of including
acknowledgments is evaluated in terms of energy consumption, throughput and latency.
The performance predicted by the analytical model has been extensively verified with simulations
using the ns-2 IEEE 802.15.4 contributed module. Throughput, energy consumption and latency
analysis is performed. Additionally, we have simulated a statistical channel model describing the radio
channel behavior around the human body to calculate the packet error rate (PER) found in a typical
WBSN under the aforementioned standard. This PER is then introduced into our analytical model.