Heterogeneous networks(HetNets)consisting of macro cells with very large antenna arrays and a secondary tier of small cells with a few antennas each can well tackle the contradiction of large coverage of the network a...Heterogeneous networks(HetNets)consisting of macro cells with very large antenna arrays and a secondary tier of small cells with a few antennas each can well tackle the contradiction of large coverage of the network and high data rate at the hot spots.However,it is not permissible to assign orthogonal pilot sequences for all the supported users due to the large number.Hence,we propose a pilot reduction scheme based on the heterogeneous system configurations and the unique topology of this HetNet.The reusing of pilot sequences causes the presence of the contaminated channel state information(CSI) and results in receivers' Quality of Service(QoS) outage.With the contaminated CSI,we provide an energy-efficient beamforming based on minimizing the total power consumption while keeping the QoS constraints satisfied and restricting the QoS outage probability below a given specification.By applying the approach of Bernstein approximation and semi-definite relaxation,we transform the original intractable chance constrained program to a convex problem conservatively.Numerical results show that the average power consumption of the proposed beamforming for our pilot reduction scheme is close to that of the perfect CSI case.Since our scheme will greatly compress the length of pilot sequence especially for those highly densified network with large number of small cells,it will be crucially helpful to put such two-tier massive multiple-input and multiple-output(MIMO) systems into practice.展开更多
Y2001-62954-110 0116855DS-CDMA系统中的波束形成性能的折衷特性研究= Investigation of the trade-off characteristics of beamform-ing performance in DS-CDMA system[会,英]/Chang,T.G.& Kim,J.H.//2000 IEEE 52nd VehicularT...Y2001-62954-110 0116855DS-CDMA系统中的波束形成性能的折衷特性研究= Investigation of the trade-off characteristics of beamform-ing performance in DS-CDMA system[会,英]/Chang,T.G.& Kim,J.H.//2000 IEEE 52nd VehicularTechnology Conference,Vol.1.—110～115(PC)研究了蜂房式DS-CDMA系统用的波束形成(BF)性能的折衷行为。介绍了DS-CDMA接收机的基带波束形成结构和信号-干扰-噪声比(SINR)降低情况。报道了波束形成性能模拟结果。参7Y2001-62954-122 0116858采用自适应盖博扩展的新天线系统中的不稳定干扰删除器=Non-stationary interference exciser in smart an-tenna systems using an adaptive Gabor expansion[会,展开更多
基金supported in part by the "863" Program of China No. 2014AA01A704National Natural Science Foundation of China No.61171080
文摘Heterogeneous networks(HetNets)consisting of macro cells with very large antenna arrays and a secondary tier of small cells with a few antennas each can well tackle the contradiction of large coverage of the network and high data rate at the hot spots.However,it is not permissible to assign orthogonal pilot sequences for all the supported users due to the large number.Hence,we propose a pilot reduction scheme based on the heterogeneous system configurations and the unique topology of this HetNet.The reusing of pilot sequences causes the presence of the contaminated channel state information(CSI) and results in receivers' Quality of Service(QoS) outage.With the contaminated CSI,we provide an energy-efficient beamforming based on minimizing the total power consumption while keeping the QoS constraints satisfied and restricting the QoS outage probability below a given specification.By applying the approach of Bernstein approximation and semi-definite relaxation,we transform the original intractable chance constrained program to a convex problem conservatively.Numerical results show that the average power consumption of the proposed beamforming for our pilot reduction scheme is close to that of the perfect CSI case.Since our scheme will greatly compress the length of pilot sequence especially for those highly densified network with large number of small cells,it will be crucially helpful to put such two-tier massive multiple-input and multiple-output(MIMO) systems into practice.
文摘Y2001-62954-110 0116855DS-CDMA系统中的波束形成性能的折衷特性研究= Investigation of the trade-off characteristics of beamform-ing performance in DS-CDMA system[会,英]/Chang,T.G.& Kim,J.H.//2000 IEEE 52nd VehicularTechnology Conference,Vol.1.—110～115(PC)研究了蜂房式DS-CDMA系统用的波束形成(BF)性能的折衷行为。介绍了DS-CDMA接收机的基带波束形成结构和信号-干扰-噪声比(SINR)降低情况。报道了波束形成性能模拟结果。参7Y2001-62954-122 0116858采用自适应盖博扩展的新天线系统中的不稳定干扰删除器=Non-stationary interference exciser in smart an-tenna systems using an adaptive Gabor expansion[会,
