Abstract: To solve the problem that multi-hops decrease the reliability in wireless sensor network with chain topology, the reliability indexes such as link reliability, energy availability for nodes, instantaneous reliability and average time without failure are presented and analyzed. The models of composite channel fading and energy for sensor nodes are established. Based on the established models, theoretical expressions of the relevant reliability index are derived. Based on the analysis on energy imbalance between the nodes, the program of initial energy is distributed. The simulation results verify the correctness of the theory. It provides a new theoretical support for analysis on the reliability of wireless sensor networks and reliability assessment or prediction.

Key words: chain topology, wireless sensor network, network reliability, channel fading model

摘要： 针对链状拓扑无线传感网络中存在的多跳过程严重降低网络可靠性的问题，提出并分析了基于多次重传策略的网络无线链路可靠性、节点能量可用性、瞬时可靠性及平均无故障时间等可靠性指标。针对契合实际的应用场景，建立了包含路径衰落和阴影衰落的复合信道模型及传感器节点的能量模型。基于所建立的模型，推导出相关可靠性指标的理论表达式。基于对节点间耗能不均衡问题的分析，提出了节能的初始能量分配方案。仿真结果验证了理论分析的正确性，为无线传感网络可靠性影响因素的分析及拓扑网络可靠性评估与预测提供了新的理论支撑。

关键词: 链状拓扑, 无线传感器网络, 网络可靠性, 信道衰落模型