Topology Based Performance Analysis of IEEE 802.15.4 for Wireless Sensor Networks

Wireless Local Area Networking standard (Wi-Fi) and the WPAN standard (Bluetooth and Zigbee) products utilize the same unlicensed 2.4 GHz ISM band. Co-existence between such wireless technologies within the same frequency spectrum is crucial to ensure that each wireless technology maintains and provides its desired performance requirements. Wireless Personal Area Networks are formed using tiny sensor devices which have several resource constraints. A new standard IEEE 802.15.4 was uniquely designed to suit personal wireless networks requirement consuming low power, provides low data rate and low cost. In this paper, an effort is made to analyze the performance of IEEE 802.15.4 in heterogeneous simulation environment. The simulation in NS2 is carried out for three types network topology with varying network density. To cover all the scenarios, we have considered scatternet, piconet and peer to peer topologies. Both beacon and non beacon enabled experiments are carried out on different traffic type. It is already known fact that IEEE 802.15.4 outperforms than IEEE 802.11 in terms of routing overhead and also power consumption. In this paper, we also discuss the reasons that could degrade the overall network performance as well as association efficiency.