Ethanol perm-selective PDMS/PVDF composite membranes were prepared by curing polydimethylsiloxane (PDMS) with various cross-linking reagents,such as tetraethoxylsilane(TEOS),γ-aminopropyltriethoxylsilane(APTEOS), phe...Ethanol perm-selective PDMS/PVDF composite membranes were prepared by curing polydimethylsiloxane (PDMS) with various cross-linking reagents,such as tetraethoxylsilane(TEOS),γ-aminopropyltriethoxylsilane(APTEOS), phenyltrimethoxylsilane(PTMOS) and octyltrimethoxylsilane(OTMOS) as well.The cross-linking density and surface properties of the PDMS active layer were adjusted by varying cross-linking reagents.The pervaporation performance of PDMS membranes cured with different cross-linking reagents was investig...展开更多
针对TM、TC、AOS、Proximity-1四种空间数据链路协议的应用局限性,对CCSDS(国际空间数据系统咨询委员会)提出的统一空间数据链路协议(Unified Space Data Link Protocol,USLP)规范进行分析,介绍了USLP传输帧主导头和数据域中各个字段的...针对TM、TC、AOS、Proximity-1四种空间数据链路协议的应用局限性,对CCSDS(国际空间数据系统咨询委员会)提出的统一空间数据链路协议(Unified Space Data Link Protocol,USLP)规范进行分析,介绍了USLP传输帧主导头和数据域中各个字段的设计驱动,以及与其他空间数据链路协议的差异。对于服务数据单元信道复用传输需求,梳理了物理信道、主信道、虚拟信道、多路复用访问信道的服务类型,明确了数据传输服务、信道复用、信道标识、服务数据单元之间的关联关系。以遥测遥控数据空间链路传输为例,分析了USLP的适用性和推荐设置。展开更多
In view of the low ranging efficiency of the conventional fixed frame-length algorithm in the inter-satellite link,an adaptive frame-length algorithm is proposed. The frame length is adjusted adaptively according to t...In view of the low ranging efficiency of the conventional fixed frame-length algorithm in the inter-satellite link,an adaptive frame-length algorithm is proposed. The frame length is adjusted adaptively according to the results of ranging and velocity measuring to improve ranging efficiency. Buffers which enable the frame length to be selected discretely and adaptively are introduced to avoid frequent hopping of the frame-length.Frame length marker is created to automatically identify the frame-length for frame synchronization procedures in receivers. The feasibility and the validity of the proposed algorithm to improve the efficiency of ranging are verified through both theoretic analysis and simulation,and the efficiency improves up to 88% when there are five buffers. This improvement can be further enhanced by increasing the number of buffers. Proper allocation of inter-satellite buffers is required to make a balance between the ranging efficiency and the system complexity.展开更多
Wireless power transfer via inductive link is becoming a popular choice as an alternate powering scheme for biomedical sensor electronics. Spiral printed circuit board (PCB) inductors are gaining attractions for wirel...Wireless power transfer via inductive link is becoming a popular choice as an alternate powering scheme for biomedical sensor electronics. Spiral printed circuit board (PCB) inductors are gaining attractions for wireless power transfer applications due to their various advantages over conventional inductors such as low-cost, batch fabrication, durability, manufacturability on flexible substrates, etc. In this work, design of a multi-spiral stacked solenoidal inductor for biomedical application in 13.56 MHz band is presented. Proposed stacking method enhances the inductance density of the inductor for a given area. This paper reports an optimization technique for design and implementation of the PCB inductors. The proposed scheme shows higher inductance and better figure-of-merit values compared to PCB inductors reported in literature, which are desirable for wireless power transfer system.展开更多
在5G时代,无线信息与能量协同传输(Simultaneous Wireless Information and Power Transfer,SWIPT)通信受到人们的广泛关注。研究基于SWIPT技术的半双工中继协作系统,分析了由一个源、多个射频能量收集中继和多个目的地所组成的两跳协...在5G时代,无线信息与能量协同传输(Simultaneous Wireless Information and Power Transfer,SWIPT)通信受到人们的广泛关注。研究基于SWIPT技术的半双工中继协作系统,分析了由一个源、多个射频能量收集中继和多个目的地所组成的两跳协作网络下行系统性能。为兼顾传输性能与实现复杂度,设计了一种基于门限选择算法的链路选择方案,并探索不同的系统关键参数对SWIPT系统性能的影响。在功率分割(PS)协议下,考虑解码转发(DF)和放大转发(AF)两种中继策略,对选择方案进行传输容量和中断概率的性能分析,给出了功率分配因子对传输容量和中断性能的影响,数值仿真结果表明,将最佳功率分配因子设置在0.3,能够较好地兼顾系统中断概率和传输容量。同时还与传统的单中继通信场景进行了比较分析,以验证所设计的链路选择方案的有效性。展开更多
基金supported by the Major State Basic Research Program of China(No.2009CB623404)National NaturalScience Foundation of China(Nos.20736003,20676067)+2 种基金National High Technology Research and Development Programof China(No.2007AA06Z317)Foundation of Ministry of Education of China(No.20070003130)Foundation of theState Key Laboratory of Chemical Engineering(SKL-ChE-08A01).
文摘Ethanol perm-selective PDMS/PVDF composite membranes were prepared by curing polydimethylsiloxane (PDMS) with various cross-linking reagents,such as tetraethoxylsilane(TEOS),γ-aminopropyltriethoxylsilane(APTEOS), phenyltrimethoxylsilane(PTMOS) and octyltrimethoxylsilane(OTMOS) as well.The cross-linking density and surface properties of the PDMS active layer were adjusted by varying cross-linking reagents.The pervaporation performance of PDMS membranes cured with different cross-linking reagents was investig...
文摘针对TM、TC、AOS、Proximity-1四种空间数据链路协议的应用局限性,对CCSDS(国际空间数据系统咨询委员会)提出的统一空间数据链路协议(Unified Space Data Link Protocol,USLP)规范进行分析,介绍了USLP传输帧主导头和数据域中各个字段的设计驱动,以及与其他空间数据链路协议的差异。对于服务数据单元信道复用传输需求,梳理了物理信道、主信道、虚拟信道、多路复用访问信道的服务类型,明确了数据传输服务、信道复用、信道标识、服务数据单元之间的关联关系。以遥测遥控数据空间链路传输为例,分析了USLP的适用性和推荐设置。
基金Supported by the National High Technology Research and Development Program of China(2013AA1548)
文摘In view of the low ranging efficiency of the conventional fixed frame-length algorithm in the inter-satellite link,an adaptive frame-length algorithm is proposed. The frame length is adjusted adaptively according to the results of ranging and velocity measuring to improve ranging efficiency. Buffers which enable the frame length to be selected discretely and adaptively are introduced to avoid frequent hopping of the frame-length.Frame length marker is created to automatically identify the frame-length for frame synchronization procedures in receivers. The feasibility and the validity of the proposed algorithm to improve the efficiency of ranging are verified through both theoretic analysis and simulation,and the efficiency improves up to 88% when there are five buffers. This improvement can be further enhanced by increasing the number of buffers. Proper allocation of inter-satellite buffers is required to make a balance between the ranging efficiency and the system complexity.
文摘Wireless power transfer via inductive link is becoming a popular choice as an alternate powering scheme for biomedical sensor electronics. Spiral printed circuit board (PCB) inductors are gaining attractions for wireless power transfer applications due to their various advantages over conventional inductors such as low-cost, batch fabrication, durability, manufacturability on flexible substrates, etc. In this work, design of a multi-spiral stacked solenoidal inductor for biomedical application in 13.56 MHz band is presented. Proposed stacking method enhances the inductance density of the inductor for a given area. This paper reports an optimization technique for design and implementation of the PCB inductors. The proposed scheme shows higher inductance and better figure-of-merit values compared to PCB inductors reported in literature, which are desirable for wireless power transfer system.
文摘在5G时代,无线信息与能量协同传输(Simultaneous Wireless Information and Power Transfer,SWIPT)通信受到人们的广泛关注。研究基于SWIPT技术的半双工中继协作系统,分析了由一个源、多个射频能量收集中继和多个目的地所组成的两跳协作网络下行系统性能。为兼顾传输性能与实现复杂度,设计了一种基于门限选择算法的链路选择方案,并探索不同的系统关键参数对SWIPT系统性能的影响。在功率分割(PS)协议下,考虑解码转发(DF)和放大转发(AF)两种中继策略,对选择方案进行传输容量和中断概率的性能分析,给出了功率分配因子对传输容量和中断性能的影响,数值仿真结果表明,将最佳功率分配因子设置在0.3,能够较好地兼顾系统中断概率和传输容量。同时还与传统的单中继通信场景进行了比较分析,以验证所设计的链路选择方案的有效性。
