UWSP：水下无线传感器网络节点休眠协议

休眠机制是传感器网络节点节约能量、延长工作寿命的重要手段之一。现存的水下传感器网络MAC协议主要考虑提高网络传输性能，对休眠机制的研究和涉及较少，并且仅有的一些休眠策略存在着因节点工作时间较为分散而导致的节点休眠-唤醒频繁的问题。节点频繁唤醒不仅会浪费额外的能量来启动电路，折损硬件寿命，还会增加数据传输冲突的概率。针对水声网络信道的独特性质，提出了一个基于树形拓扑结构的水下传感器网络节点休眠算法，该算法能够有效缩短节点唤醒次数，延长休眠时间，并保证端到端的传播延迟不受休眠时间的影响。该算法无冲突也无需预约信道，保证了较高的网络流量。最后，通过仿真实验验证了算法的可用性和效能。

UWSP: sleeping algorithms for underwater sensor network

Sleeping scheme is one of the key means of saving energy for wireless sensor network. However, existing MAC protocols for underwater sensor network (UWSN) mainly focus on maximizing throughput but ignore sleeping schemes. Moreover, in existing sleeping schemes nodes wake up rapidly, which will loss the life of hardware, waste energy to open/close circuits, and increase collision probability. So, a tree topology based sleeping algorithm for UWSN was proposed, which utilizes the special characteristics of underwater acoustic channel. This algorithm could reduce wakeup frequency, prolong sleeping time and keep the end to end delay from being affected by sleeping time. This algorithm has no collision and no channel reservation and its usability and capability have been verified by simulation methods.