Performance and Fairness Enhancement in ZigBee Networks

II III Acknowledgements I would like to deliver my deepest appreciation to my instructors, Dr. Venkatesha Prasad Ranga Rao and Huaizhou Shi for their invaluable support, guidance and encouragement during the whole thesis project. I would like to express my gratitude to them for the time we spent together discussing the simulations and results. I am also very grateful to Dr.Cheng Guo for his guidance and suggestions. I also would like to express my sincere thanks to Diptanil Debbarma and Dr.Javad Vazifehdan who gave me lots of interesting and valuable suggestions for my thesis and other projects. I would like to thank Martin Jacobsson for his precious advices on the real life traffic in my simulations. I would also like to thank my supervisor Prof.dr.ir. Ignas Niemegeers for his help and guidance, who was also as a wonderful lecturer during my study. Additionally, I want to thank Dr.ir.Bert Jan Kooij for taking time to give feedback on my thesis. Furthermore, I would like to thank WMC group for giving me this precious opportunity to work on this interesting project and allowing me to work with all these wonderful people. I am very grateful to all my fellow students, for the pleasant and stimulating atmosphere. Last but not the least, I would like to thank my families for their support and encouragement. Also I want to say thank you to my friends who give me help during the whole project. Abstract ZigBee is a robust wireless communication standard which is based on IEEE 802.15.4. It can be implemented in various applications, for example, health care networks, smart home networks and plenty of sensor networks. However, the performance of ZigBee is also critically limited by low packet delivery ratio and unfairness on network accessing amongst nodes in ZigBee networks with large amount of nodes (more than 100 or so in our simulations). Therefore, how to fairly and efficiently access the network and deliver packets is one of the crucial issues in ZigBee networks. However, there are many different network parameters and different parameters would influence the performance and fairness in different manors. Hence, we have measured the influence of performance by different values of various network parameters in ZigBee networks, such as network depth, retransmission time, size of the network and traffic etc. The simulation results show that the packet delivery ratio and fairness amongst nodes are influenced much more significantly by …