It has been reported that, through the evanescent near fields, the strongly coupled magnetic resonance is able to achieve an efficient mid-range Wireless Power Transfer (WPT) beyond the characteristic size of the reso...It has been reported that, through the evanescent near fields, the strongly coupled magnetic resonance is able to achieve an efficient mid-range Wireless Power Transfer (WPT) beyond the characteristic size of the resonator. Recent studies on of the relay effect of the WPT allow more distant and flexible energy transmission. These new developments hold a promise to construct a fully wireless Body Sensor Network (wBSN) using the new mid-range WPT theory. In this paper, a general optimization strategy for a WPT network is presented by analysis and simulation using the coupled mode theory. Based on the results of theoretical and computational study, two types of thin-film resonators are designed and prototyped for the construction of wBSNs. These resonators and associated electronic components can be integrated into a WPT platform to permit wireless power delivery to multiple wearable sensors and medical implants on the surface and within the human body. Our experiments have demonstrated the feasibility of the WPT approach.展开更多
为了提高认知无线携能通信(Simultaneous Wireless Information and Power Transfer,SWIPT)网络的频谱利用率并改善其能量受限情况,本文研究智能反射面(Intelligent Reflecting Surface,IRS)辅助的认知SWIPT网络,其中主用户网络以覆盖...为了提高认知无线携能通信(Simultaneous Wireless Information and Power Transfer,SWIPT)网络的频谱利用率并改善其能量受限情况,本文研究智能反射面(Intelligent Reflecting Surface,IRS)辅助的认知SWIPT网络,其中主用户网络以覆盖方式与次用户网络共享频谱,而次用户发射机同时为主用户发射机供能并与次用户接收机传输信息。提出次用户网络吞吐量优化算法,在满足次用户发射机的最大发射功率约束、主用户网络的最小吞吐量约束、总时隙约束以及智能反射面移约束的条件下,联合优化次用户发射机的波束成形矢量、时隙分配和智能反射面反射相移,最大化次用户网络吞吐量。该问题的优化变量相互耦合并且结构高度非凸,难以直接求解。所提算法采用交替优化、半正定松弛以及连续凸逼近方式,将原问题转化为三个子问题进行迭代求解。仿真结果表明与已有基准方案相比,所提算法能明显提高次用户网络的吞吐量。展开更多
In Wireless Sensor Networks (WSN), the lifetime of sensors is the crucial issue. Numerous schemes are proposed to augment the life time of sensors based on the wide range of parameters. In majority of the cases, the c...In Wireless Sensor Networks (WSN), the lifetime of sensors is the crucial issue. Numerous schemes are proposed to augment the life time of sensors based on the wide range of parameters. In majority of the cases, the center of attraction will be the nodes’ lifetime enhancement and routing. In the scenario of cluster based WSN, multi-hop mode of communication reduces the communication cast by increasing average delay and also increases the routing overhead. In this proposed scheme, two ideas are introduced to overcome the delay and routing overhead. To achieve the higher degree in the lifetime of the nodes, the residual energy (remaining energy) of the nodes for multi-hop node choice is taken into consideration first. Then the modification in the routing protocol is evolved (Multi-Hop Dynamic Path-Selection Algorithm—MHDP). A dynamic path updating is initiated in frequent interval based on nodes residual energy to avoid the data loss due to path extrication and also to avoid the early dying of nodes due to elevation of data forwarding. The proposed method improves network’s lifetime significantly. The diminution in the average delay and increment in the lifetime of network are also accomplished. The MHDP offers 50% delay lesser than clustering. The average residual energy is 20% higher than clustering and 10% higher than multi-hop clustering. The proposed method improves network lifetime by 40% than clustering and 30% than multi-hop clustering which is considerably much better than the preceding methods.展开更多
文摘It has been reported that, through the evanescent near fields, the strongly coupled magnetic resonance is able to achieve an efficient mid-range Wireless Power Transfer (WPT) beyond the characteristic size of the resonator. Recent studies on of the relay effect of the WPT allow more distant and flexible energy transmission. These new developments hold a promise to construct a fully wireless Body Sensor Network (wBSN) using the new mid-range WPT theory. In this paper, a general optimization strategy for a WPT network is presented by analysis and simulation using the coupled mode theory. Based on the results of theoretical and computational study, two types of thin-film resonators are designed and prototyped for the construction of wBSNs. These resonators and associated electronic components can be integrated into a WPT platform to permit wireless power delivery to multiple wearable sensors and medical implants on the surface and within the human body. Our experiments have demonstrated the feasibility of the WPT approach.
文摘为了提高认知无线携能通信(Simultaneous Wireless Information and Power Transfer,SWIPT)网络的频谱利用率并改善其能量受限情况,本文研究智能反射面(Intelligent Reflecting Surface,IRS)辅助的认知SWIPT网络,其中主用户网络以覆盖方式与次用户网络共享频谱,而次用户发射机同时为主用户发射机供能并与次用户接收机传输信息。提出次用户网络吞吐量优化算法,在满足次用户发射机的最大发射功率约束、主用户网络的最小吞吐量约束、总时隙约束以及智能反射面移约束的条件下,联合优化次用户发射机的波束成形矢量、时隙分配和智能反射面反射相移,最大化次用户网络吞吐量。该问题的优化变量相互耦合并且结构高度非凸,难以直接求解。所提算法采用交替优化、半正定松弛以及连续凸逼近方式,将原问题转化为三个子问题进行迭代求解。仿真结果表明与已有基准方案相比,所提算法能明显提高次用户网络的吞吐量。
文摘In Wireless Sensor Networks (WSN), the lifetime of sensors is the crucial issue. Numerous schemes are proposed to augment the life time of sensors based on the wide range of parameters. In majority of the cases, the center of attraction will be the nodes’ lifetime enhancement and routing. In the scenario of cluster based WSN, multi-hop mode of communication reduces the communication cast by increasing average delay and also increases the routing overhead. In this proposed scheme, two ideas are introduced to overcome the delay and routing overhead. To achieve the higher degree in the lifetime of the nodes, the residual energy (remaining energy) of the nodes for multi-hop node choice is taken into consideration first. Then the modification in the routing protocol is evolved (Multi-Hop Dynamic Path-Selection Algorithm—MHDP). A dynamic path updating is initiated in frequent interval based on nodes residual energy to avoid the data loss due to path extrication and also to avoid the early dying of nodes due to elevation of data forwarding. The proposed method improves network’s lifetime significantly. The diminution in the average delay and increment in the lifetime of network are also accomplished. The MHDP offers 50% delay lesser than clustering. The average residual energy is 20% higher than clustering and 10% higher than multi-hop clustering. The proposed method improves network lifetime by 40% than clustering and 30% than multi-hop clustering which is considerably much better than the preceding methods.