This paper considers an underwater acoustic sensor network with one mobile surface node to collect data from multiple underwater nodes,where the mobile destination requests retransmission from each underwater node ind...This paper considers an underwater acoustic sensor network with one mobile surface node to collect data from multiple underwater nodes,where the mobile destination requests retransmission from each underwater node individually employing traditional automatic-repeat-request(ARQ) protocol.We propose a practical node cooperation(NC) protocol to enhance the collection efficiency,utilizing the fact that underwater nodes can overhear the transmission of others.To reduce the source level of underwater nodes,the underwater data collection area is divided into several sub-zones,and in each sub-zone,the mobile surface node adopting the NC protocol could switch adaptively between selective relay cooperation(SRC) and dynamic network coded cooperation(DNC) .The difference of SRC and DNC lies in whether or not the selected relay node combines the local data and the data overheard from undecoded node(s) to form network coded packets in the retransmission phase.The NC protocol could also be applied across the sub-zones due to the wiretap property.In addition,we investigate the effects of different mobile collection paths,collection area division and cooperative zone design for energy saving.The numerical results showthat the proposed NC protocol can effectively save energy compared with the traditional ARQ scheme.展开更多
Since mobile nodes such as autonomous underwater vehicles can effectively expand network coverage,underwater acoustic networks with mobile nodes have attracted more and more attention in recent years.To ensure the tim...Since mobile nodes such as autonomous underwater vehicles can effectively expand network coverage,underwater acoustic networks with mobile nodes have attracted more and more attention in recent years.To ensure the timely access of a mobile node without disturbing the normal transmission of data packets from static nodes,a sequence-scheduled and query-based medium access control protocol is proposed in this paper.The underwater nodes with data packets to be transmitted reply with a control packet for channel reservation after receiving the broadcast control packet of the buoy,then the reserved nodes transmit their data packets as the order calculated by the buoy.We develop a mechanism to adjust the transmission order of the control packets sent by the underwater nodes in the handshake phase to reduce the collision and guarantee the success rate of reservation,and a query is initiated when the reserved control packet of the mobile node is not received by the buoy in the handshake to respond to the data transmission request of the mobile node in time.Simulations show that the maximum nodal throughput of the proposed MAC protocol increases by at least 20%and the access delay of the mobile node decreases by about 90%,compared to the two reference protocols.Besides,the average access probability of the mobile node in the proposed protocol is more than 90%.展开更多
Wireless technology for underwater communication possesses a wide range of potential application, but it is still a relatively unexplored area in many aspects concerning modems physical design. A step towards future d...Wireless technology for underwater communication possesses a wide range of potential application, but it is still a relatively unexplored area in many aspects concerning modems physical design. A step towards future deployment of underwater networks is the reduction of power consumption. Therefore, asynchronous wakeup systems need to be integrated within the physical layer design while avoiding the use of additional transducers. This paper offers a practical and generic solution to adapt data reception and transmission together with asynchronous wakeup sub-systems in acoustic underwater modem architectures using a low power and low cost solution. The proposal has been implemented in a real prototype with success.展开更多
针对水声传感器网络中移动定位算法的误差和鲁棒性问题,提出两种蒙特卡罗移动定位算法:CRMCL(Circular Ring Monte Carlo Localization)和PRMCL(Particle Swarm Optimization for Circular Ring Monte Carlo Localization).CRMCL利用1...针对水声传感器网络中移动定位算法的误差和鲁棒性问题,提出两种蒙特卡罗移动定位算法:CRMCL(Circular Ring Monte Carlo Localization)和PRMCL(Particle Swarm Optimization for Circular Ring Monte Carlo Localization).CRMCL利用1跳锚节点构建圆形采样区域和圆环过滤器.通过定义样本密度得到合理的样本数,论证圆环参数与过滤区域面积的关系.通过仿真实验得到合理的圆环参数,并以此构建高效的过滤器,降低定位误差.PRMCL使用粒子群算法优化CRMCL过滤后的样本,降低了无效样本的数目,增强了算法的鲁棒性.仿真表明,在不需要额外硬件的情况下,CRMCL和PRMCL比蒙特卡罗及其改进算法误差小、鲁棒性强.展开更多
基金supported in part by National Key Research and Development Program of China under Grants No.2016YFC1400200 and 2016YFC1400204National Natural Science Foundation of China under Grants No.41476026,41676024 and 41376040Fundamental Research Funds for the Central Universities of China under Grant No.220720140506
文摘This paper considers an underwater acoustic sensor network with one mobile surface node to collect data from multiple underwater nodes,where the mobile destination requests retransmission from each underwater node individually employing traditional automatic-repeat-request(ARQ) protocol.We propose a practical node cooperation(NC) protocol to enhance the collection efficiency,utilizing the fact that underwater nodes can overhear the transmission of others.To reduce the source level of underwater nodes,the underwater data collection area is divided into several sub-zones,and in each sub-zone,the mobile surface node adopting the NC protocol could switch adaptively between selective relay cooperation(SRC) and dynamic network coded cooperation(DNC) .The difference of SRC and DNC lies in whether or not the selected relay node combines the local data and the data overheard from undecoded node(s) to form network coded packets in the retransmission phase.The NC protocol could also be applied across the sub-zones due to the wiretap property.In addition,we investigate the effects of different mobile collection paths,collection area division and cooperative zone design for energy saving.The numerical results showthat the proposed NC protocol can effectively save energy compared with the traditional ARQ scheme.
基金This work was supported by National Basic Research Program of China(No.2018YFC1405904).
文摘Since mobile nodes such as autonomous underwater vehicles can effectively expand network coverage,underwater acoustic networks with mobile nodes have attracted more and more attention in recent years.To ensure the timely access of a mobile node without disturbing the normal transmission of data packets from static nodes,a sequence-scheduled and query-based medium access control protocol is proposed in this paper.The underwater nodes with data packets to be transmitted reply with a control packet for channel reservation after receiving the broadcast control packet of the buoy,then the reserved nodes transmit their data packets as the order calculated by the buoy.We develop a mechanism to adjust the transmission order of the control packets sent by the underwater nodes in the handshake phase to reduce the collision and guarantee the success rate of reservation,and a query is initiated when the reserved control packet of the mobile node is not received by the buoy in the handshake to respond to the data transmission request of the mobile node in time.Simulations show that the maximum nodal throughput of the proposed MAC protocol increases by at least 20%and the access delay of the mobile node decreases by about 90%,compared to the two reference protocols.Besides,the average access probability of the mobile node in the proposed protocol is more than 90%.
文摘Wireless technology for underwater communication possesses a wide range of potential application, but it is still a relatively unexplored area in many aspects concerning modems physical design. A step towards future deployment of underwater networks is the reduction of power consumption. Therefore, asynchronous wakeup systems need to be integrated within the physical layer design while avoiding the use of additional transducers. This paper offers a practical and generic solution to adapt data reception and transmission together with asynchronous wakeup sub-systems in acoustic underwater modem architectures using a low power and low cost solution. The proposal has been implemented in a real prototype with success.
文摘针对水声传感器网络中移动定位算法的误差和鲁棒性问题,提出两种蒙特卡罗移动定位算法:CRMCL(Circular Ring Monte Carlo Localization)和PRMCL(Particle Swarm Optimization for Circular Ring Monte Carlo Localization).CRMCL利用1跳锚节点构建圆形采样区域和圆环过滤器.通过定义样本密度得到合理的样本数,论证圆环参数与过滤区域面积的关系.通过仿真实验得到合理的圆环参数,并以此构建高效的过滤器,降低定位误差.PRMCL使用粒子群算法优化CRMCL过滤后的样本,降低了无效样本的数目,增强了算法的鲁棒性.仿真表明,在不需要额外硬件的情况下,CRMCL和PRMCL比蒙特卡罗及其改进算法误差小、鲁棒性强.
