This paper proposes second-order consensus protocols and gives a measure of the robustness of the protocols to the time-delays existing in the dynamics of agents with second-order dynamics. By employing a frequency do...This paper proposes second-order consensus protocols and gives a measure of the robustness of the protocols to the time-delays existing in the dynamics of agents with second-order dynamics. By employing a frequency domain method, it is proven that the information states achieve second-order consensus asymptotically for appropriate time-delay if the topology of the network is connected. Particularly, a nonconservative upper bound on the fixed time-delay that can be tolerated is found. The consensus protocols are distributed in the sense that each agent only needs information from its neighboring agents, which makes the proposed protocols scalable. It reduces the complexity of connections among agents significantly. Simulation results are provided to verify the effectiveness of the theoretical results for second-order consensus in networks in the presence of time-delays existing in the dynamics of agents.展开更多
摘要针对卫星少缆化互连发展需求,提出采用超宽带(Ultra-wide Band,UWB)技术构建星载无线网络替代传统有线传输方式。阐述了星载网络内部时钟与系统外部时钟的不同涵义,介绍并比较了不同机制的无线网络时间同步算法。基于UWB无线节点,采用泛洪时间同步协议(Flooding Time Synchronization Protocol,FTSP)实现无线节点网络内部与外部时钟的同步。搭建星型无线网络,在3种同步周期和4种同步时间表深度的条件下测试验证同步效果,结果表明内外部时钟的最大正负偏差可以维持在10μs以内。
摘要水声无线传感器网络(Underwater Acoustic Wireless Sensor Networks,UAWSN)由于复杂的水下环境,面临着节点能量有限、网络传播时延大及吞吐量较低等挑战。为解决这些问题,提出一种时隙状态翻转自适应水声传感网MAC协议(Time-slot State Flip Adaptive Media Access Control Protocol for Underwater Acoustic Sensor Networks,SSFA)。协议通过伪随机方式生成初始时隙调度,基于强化学习的思想根据网络状态自适应动态调整时隙调度计划,并通过冲突检测机制评估当前信道状况,以确定发送数据包的时机,减少了高动态、长时延水声传感网中的数据冲突和网络能耗,提高了网络整体的吞吐量。仿真实验结果显示,与Aloha、S-FAMA和UW-Seedex相比,SSFA协议在吞吐量方面平均提高了35.3%、140.5%和12.7%,在端到端时延方面平均降低了77.8%、40%和30.8%。
基金Supported by the National Natural Science Foundation of China (60574088, 60274014)
摘要This paper proposes second-order consensus protocols and gives a measure of the robustness of the protocols to the time-delays existing in the dynamics of agents with second-order dynamics. By employing a frequency domain method, it is proven that the information states achieve second-order consensus asymptotically for appropriate time-delay if the topology of the network is connected. Particularly, a nonconservative upper bound on the fixed time-delay that can be tolerated is found. The consensus protocols are distributed in the sense that each agent only needs information from its neighboring agents, which makes the proposed protocols scalable. It reduces the complexity of connections among agents significantly. Simulation results are provided to verify the effectiveness of the theoretical results for second-order consensus in networks in the presence of time-delays existing in the dynamics of agents.