相比于陆地无线传感器网络, 水下传感器网络拥有更大的传播时延, 导致许多已经比较成熟的MAC协议不能直接应用于水下。提出了基于压缩感知的水下传感器网络预约多址接入协议, 充分利用水下环境中的长传播时延, 使网络中各节点能够在时间和空间上对信道资源进行共用, 实现多个用户同时进行信道预约, 提高了信道的利用率。在考虑多用户分集基础上, 该协议使成功预约到信道的用户可以利用有限的全部带宽资源进行高速传输, 以此来提高整个网络的吞吐性能。仿真结果表明, 与传统的RTS/CTS方案相比, 该协议具有更高效的信道预约能力, 更高的数据传输效率, 以及更好的吞吐性能。
Compared with the terrestrial wireless sensor networks, underwater sensor network has a longer propagation delay. Thus, the existing MAC protocols for wireless sensor network can not be directly applied in underwater environment. This paper proposed a channel reservation multiple access protocol based on compressed sensing (CS) in underwater sensor networks. The novel scheme made full use of the long propagation delay in the underwater environment, in order that each node could share the channel resource in both time and space dimension. By virtue of the newly arisen CS theory, the scheme achieved simulta-neously channel reservation for multiple users and improved channel utilization of the underwater sensor networks. By taking multiuser diversity into consideration, it admitted the best users whose channel access requests to take advantage of the limited bandwidth for high-speed transmission, leading to an improved system throughput for the entire network. Simulation results show that, compared to the traditional RTS/CTS scheme, the proposed protocol has higher channel reservation capability, higher data transmission efficiency, and best throughput performance.