A Coexistence Model of IEEE 802.15.4 and IEEE 802.11b/g

IEEE 802.15.4 was developed to meet the needs for low-rate wireless communication. However, due to its low power, IEEE 802.15.4 is potentially vulnerable to interference by other wireless technologies having much higher power and working in the same industrial, scientific, and medical (ISM) band such as IEEE 802.11 b/g. The paper therefore focuses on the coexistence impact of IEEE 802.11 b/g on the IEEE 802.15.4. In this paper, we present a coexistence model of IEEE 802.15.4 and IEEE 802.11 b/g, which exposes the interactive behavior between these two standards and therefore accurately explains their coexistence performance. The model focuses on two aspects, namely power and timing. These two aspects jointly impose different impacts on the performance of IEEE 802.15.4 networks, depending on coexistence situations. To classify the coexistence situations, we introduce a concept of coexistence range, by extending the concept of sensing and interference ranges across different wireless standards. We characterize the coexistence behavior in each coexistence range and identify for each range the underlying coexistence mechanism and protocol interactions. Analytical models are proposed for the case of saturated traffic and simulation results are presented to validate the model.