基于奇偶轮成簇和双簇首的非均匀分簇协议

针对无线传感器网络（WSN）存在"能量热区"和系统鲁棒性较差的问题，提出了一种基于奇偶轮成簇和双簇首的非均匀分簇协议（UCOD）。首先，优化竞争半径函数，使簇首分布更合理；其次，引入主副簇首机制，当主簇头能量低于设定的能量阈值时进入休眠，副簇头同时执行主副簇头功能以提高鲁棒性；然后，采用奇偶轮不同的成簇机制，奇数轮全局节点竞争簇首，偶数轮在奇数轮簇内选择簇首，减少节点入簇选择耗能；最后，将网络分级，节点根据位置、能量、转发次数和周围节点数在下一级选择中继节点。仿真结果表明，UCOD与分布式能量均衡非均匀分簇协议（DEBUC）和基于非均匀分簇的无线传感器网络分层路由协议（HRPNC）相比，网络生命周期延长了28.4%和13.7%，丢包率在簇首损坏50%的情况下降低了39.1和27.5个百分点。实验结果表明，UCOD能够有效提高能量效率和系统鲁棒性。

Uneven clustering protocol based on odd-even round clustering and double cluster head

According to the problem of "energy hotspot" and poor system robustness in Wireless Sensor Network (WSN), an Uneven Clustering protocol based on Odd-even round clustering and Double cluster head (UCOD) was proposed. Firstly, the competitive radius function was optimized to make the cluster head distribution more reasonable. Secondly, main and vice cluster head mechanism was introduced. The main cluster head slept when its energy was lower than the set energy threshold, and the vice cluster head carried out the functions of main and vice cluster heads to improve robustness. Then, different clustering mechanisms for odd and even rounds were adopted. In odd-numbered rounds, global nodes competed for cluster heads; and in even-numbered rounds cluster heads were selected in odd-numbered rounds; which could reduce nodes' energy consumption in cluster selection. Finally, the network was ranked and the node selected the relay node at the next level according to the location, energy, times of forwarding and the number of surrounding nodes. In the comparison experiments with DEBUC (Distributed Energy-Balanced Unequal Clustering routing protocol) and HRPNC (Hierarchical Routing Protocol for wireless sensor networks based on Non-uniform Clustering), the network cycle of UCOD was increased by 28.4% and 13.7% respectively, and the packet loss rate of UCOD was reduced by 39.1 and 27.5 percentage points at a cluster head damage of 50%. The experimental results show that UCOD can effectively improve energy efficiency and system robustness.