中文摘要：

为了提高环境监测传感网系统（WSNs）的性能，研究了传感网系统的数据传输战略；针对系统节点之间链路质量不稳定会造成丢包现象，采用重传机制提高数据传输可靠性会增加数据包的延迟和带来额外的能量开销的问题，提出了一种基于系统最低寿命的重传机制。首先，基于节点位置信息和链路相关性对节点进行分簇；其次，基于分簇节点丢包统计信息和接收信号强度指示（RSSI）综合评估链路质量；最后，根据综合评估获得的链路质量信息以及系统要求寿命和节点剩余时间，提出一种满足最低寿命要求的重传方法（EasiAR）。实际实验表明，EasiAR能够在保证系统最低寿命要求的前提下，提高数据传输的可靠性，并降低数据包的传输延迟。

英文摘要：

To improve the performance of wireless sensor networks for environment monitoring, the networks＇ data transmission strategies were studied, and a retransmission mechanism considering the minimum system life was proposed to solve the problems of packet loss caused by the unstable link quality among nodes as well as increasement of packet delay and additional energy cost caused by adopting retransmission to improve the reliability of data transmission. The research was conducted according to the steps below. Firstly, the nodes were clustered based on their location information and link relevance. Secondly, the link quality was assessed comprehensively based on the statistics of packet loss and the receive signal strength indicator （RSSI） in intra-cluster nodes. Finally, according to the link quality information from the comprehensive assessment, as well as the lifetime requirement of the system and the remaining work time of the node, a retransmission method （EasiAR） meeting the requirement of minimum lifetime of the system was proposed. The practical experiments indicate that EasiAR can achieve reliable packet transmission and reduce transmission delay while ensuring minimum lifetime of the system.