Energy efficiency is an important criterion for routing algorithms in the wireless sensor network. Cooperative routing can reduce energy consumption effectively stemming from its diversity gain advantage. To solve the...Energy efficiency is an important criterion for routing algorithms in the wireless sensor network. Cooperative routing can reduce energy consumption effectively stemming from its diversity gain advantage. To solve the energy consumption problem and maximize the network lifetime, this paper proposes a Virtual Multiple Input Multiple Output based Cooperative Routing algorithm(VMIMOCR). VMIMOCR chooses cooperative relay nodes based on Virtual Multiple Input Multiple Output Model, and balances energy consumption by reasonable power allocation among transmitters, and decides the forwarding path finally. The experimental results show that VMIMOCR can improve network lifetime from 37% to 348% in the medium node density, compared with existing routing algorithms.展开更多
User pairing strategy for virtual multi-input multi-output （VMIMO） has been widely studied to improve system throughput, but most studies are based on perfect channel state information （CSI） and uniform power allo...User pairing strategy for virtual multi-input multi-output （VMIMO） has been widely studied to improve system throughput, but most studies are based on perfect channel state information （CSI） and uniform power allocation. However, perfect CSI is very difficult or even impossible to obtain in practical system. Moreover power allocation has significant impact on algorithm performance. Therefore, in this paper, a low-complex joint user pairing and power allocation algorithm based on aggressive discrete stochastic optimization and Lagrangian dual solution is proposed for uplink VMIMO with imperfect CSI. Simulation results show that the proposed algorithm can achieve desirable throughput performance, and restrict inter-user interference （IUI） efficiently.展开更多
Abstract Wireless sensor networks （WSNs） have been paid more attention in recent years. However, energy efficiency is still a troublesome issue in real WSN applications. In this paper, we studied the performance of ...Abstract Wireless sensor networks （WSNs） have been paid more attention in recent years. However, energy efficiency is still a troublesome issue in real WSN applications. In this paper, we studied the performance of a virtual multiple-input multiple-output （VMIMO）-based communications architecture for WSN applications. By analyzing the bit error rate （BER） of each cooperative branch, we presented the closed-form expressions for optimal transmitting power （TP） scheme in K~ 1 VMIMO cluster-based system. Then, the impact of the number of cooperating nodes on energy efficiency with energy-per- useful-bit （EPUB） metric was studied. Performance enhancement of the strategy with optimal TP assignment was verified by extensive simulations under different scenes. A thorough explanation of optimally choosing the number of cooperating nodes was also delivered by the aid of simulation verifications.展开更多
针对多用户配对虚拟MIMO(multiple input multiple output)安全性差,对信道估计器依赖性强的问题,提出一种基于非相干空频码(non-coherent space frequency code,NSFC)和正交频分复用(orthogonal frequency division multiplexing,OFDM...针对多用户配对虚拟MIMO(multiple input multiple output)安全性差,对信道估计器依赖性强的问题,提出一种基于非相干空频码(non-coherent space frequency code,NSFC)和正交频分复用(orthogonal frequency division multiplexing,OFDM)的非协作式虚拟MIMO。在分析NSFC成对错误概率的基础上,给出能满足全分集阶数和最大编码增益的编码准则。为了获得平行子信道传输效果,利用信道循环矩阵奇异值分解(singular value decomposition,SVD)后得到的酉矩阵分别进行预编码和预解码。基于最优NSFC和OFDM预编解码,提出一种新颖的虚拟MIMO策略。该虚拟MIMO在收发两端均无需信道瞬时信息,以非协作方式在单天线内模拟多天线收发效果。理论和仿真分析结果表明,虚拟MIMO系统能有效逼近实际理想MIMO的系统容量和误比特率性能,显著降低了虚拟MIMO系统的检测门限。展开更多
基金supported by the National Basic Research Program of China (973 program) (Grant No.2012CB315805)the National Natural Science Foundation of China (Grant No.61472130 and 61572184)
文摘Energy efficiency is an important criterion for routing algorithms in the wireless sensor network. Cooperative routing can reduce energy consumption effectively stemming from its diversity gain advantage. To solve the energy consumption problem and maximize the network lifetime, this paper proposes a Virtual Multiple Input Multiple Output based Cooperative Routing algorithm(VMIMOCR). VMIMOCR chooses cooperative relay nodes based on Virtual Multiple Input Multiple Output Model, and balances energy consumption by reasonable power allocation among transmitters, and decides the forwarding path finally. The experimental results show that VMIMOCR can improve network lifetime from 37% to 348% in the medium node density, compared with existing routing algorithms.
基金supported by the National Natural Science Foundation of China (61271182)the National Natural Science Funds of China for Young Scholar (61001115)the National Science and Technology Major Project (2011ZX03001-007-03)
文摘User pairing strategy for virtual multi-input multi-output （VMIMO） has been widely studied to improve system throughput, but most studies are based on perfect channel state information （CSI） and uniform power allocation. However, perfect CSI is very difficult or even impossible to obtain in practical system. Moreover power allocation has significant impact on algorithm performance. Therefore, in this paper, a low-complex joint user pairing and power allocation algorithm based on aggressive discrete stochastic optimization and Lagrangian dual solution is proposed for uplink VMIMO with imperfect CSI. Simulation results show that the proposed algorithm can achieve desirable throughput performance, and restrict inter-user interference （IUI） efficiently.
文摘Abstract Wireless sensor networks （WSNs） have been paid more attention in recent years. However, energy efficiency is still a troublesome issue in real WSN applications. In this paper, we studied the performance of a virtual multiple-input multiple-output （VMIMO）-based communications architecture for WSN applications. By analyzing the bit error rate （BER） of each cooperative branch, we presented the closed-form expressions for optimal transmitting power （TP） scheme in K~ 1 VMIMO cluster-based system. Then, the impact of the number of cooperating nodes on energy efficiency with energy-per- useful-bit （EPUB） metric was studied. Performance enhancement of the strategy with optimal TP assignment was verified by extensive simulations under different scenes. A thorough explanation of optimally choosing the number of cooperating nodes was also delivered by the aid of simulation verifications.
文摘针对多用户配对虚拟MIMO(multiple input multiple output)安全性差,对信道估计器依赖性强的问题,提出一种基于非相干空频码(non-coherent space frequency code,NSFC)和正交频分复用(orthogonal frequency division multiplexing,OFDM)的非协作式虚拟MIMO。在分析NSFC成对错误概率的基础上,给出能满足全分集阶数和最大编码增益的编码准则。为了获得平行子信道传输效果,利用信道循环矩阵奇异值分解(singular value decomposition,SVD)后得到的酉矩阵分别进行预编码和预解码。基于最优NSFC和OFDM预编解码,提出一种新颖的虚拟MIMO策略。该虚拟MIMO在收发两端均无需信道瞬时信息,以非协作方式在单天线内模拟多天线收发效果。理论和仿真分析结果表明,虚拟MIMO系统能有效逼近实际理想MIMO的系统容量和误比特率性能,显著降低了虚拟MIMO系统的检测门限。
