在M2M 通信中，终端节点大部分是由能量受限的电池供电，因此研究节点的能耗问题对延长通信的寿命至关重要. 为此，研究M2M 通信中具有认知能力的终端节点如何利用相互之间的协同传输来降低能量消耗. 由于次级用户的通信受限于授权信道的频谱可用性，传统的基于香农信道容量的中继分配不再适用，于是采用有效
信道容量(effective channel capacity, ECC) 的概念，同时考虑节点的剩余能量，利用匹配算法设计出最优中继分配策略. 仿真结果表明，该中继分配策略具有低能耗和公平性上的优势.
In machine-to-machine (M2M) communications, terminal nodes are mostly powered by batteries
that are energy constrained. Therefore energy consumption of the nodes is a crucial issue for the life of communications.
This paper studies how the terminal nodes with cognitive ability can use cooperative transmission
among each other to reduce energy consumption. As communications of secondary users are limited to the
available authorized channel spectrum, the traditional relay assignment based on Shannon channel capacity
is not applicable. Using the concept of effective channel capacity (ECC) and taking into account the nodes’
residual energy, we propose an optimal relay assignment strategy by using a matching algorithm. Simulation
results show that the proposed assignment strategy has advantages in low energy consumption and fairness.
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