Retransmission Algorithm for Channel Allocation in IEEE 802.15.4 LR-WPAN

摘要

IEEE 802.15.4 was developed for simple, low-power and low-cost wireless communication. It employs the slotted carrier sense multiple access with collision avoidance (CSMA/CA) for the contention mechanism. The blind backoff process in the slotted CSMA/CA will cause lower channel utilization. Sensor node performs backoff process immediately when the clear channel assessment (CCA) detecting busy channel. If a collision occurs, CSMA/CA algorithm executes retransmission operation. If packet retransmission fails for three times, this packet is dropped. However if this dropped packet has emergency information, the reliability of data transmission and Quality of Service (QoS) are reduce. In this paper, we design a retransmission algorithm for channel allocation in IEEE 802.15.4 LR-WPAN. To conduct performance analysis, we used an OPNET network simulator. A performance analysis shows that the proposed algorithm reduces the dropped packet and throughput, so proposed algorithm improves the reliability of data transmission and Quality of Service (QoS).