Routing Research Based On IEEE 802.15.4

IEEE802.15.4 standard is developed by IEEE Association for Low-Rate Wireless Personal Network(LR-WPAN), and it defines the physical layer and MAC layer for LR-WPAN. The standard has many advantages, such as the simple structure, short transmission distance, low power, etc, so it is very suitable for wireless sensor networks.In wireless sensor networks, the energy of sensor nodes is limited and generally can not be supplied, so the routing protocol needs to be energy-efficient. Simultaneously, the number of sensor nodes is often ennormous and sensor nodes has the information on partial topology, so the routing protocols can only choose the appropriate path route based on the local network.In order to improve the performance of routing, this paper first optimizes the fixed duty-cycle of IEEE 802.15.4 and proposes a dynamic duty adaption scheme DSBA(Dynamic Superframeorder Beaconorder Adaption). In DSBA, two main parameters of duty cycle can be dynamically adjusted through comparing the number of current data frames with the one of data frames in the next period in order to improve the transmission performance. Next, in order to decrease the IEEE 802.15.4 beacon collision, an individual time division protocol-ITD based on IEEE802.15.4 is proposed. In ITD, the coordinator assigns the time division(TD) to each associated device so that different devices transmit a beacon frame at different time slice. In this way, the beacon collision is reduced and the transmission performance is improved. Last,based on the work on optimizing IEEE 802.15.4 performance, this paper proposes a routing scheme which can be achieved in the link layer in order to reduce the latency of route discovery, and encapsulating/decapsulating a message and lower the energy consumption caused by these operations..The performance of this scheme is evaluated and the data results show that this routing scheme substantially reduces the routing establishment delay and cost, and also lowers the energy consumption.