This paper proposes a virtual router cluster system based on the separation of the control plane and the data plane from multiple perspectives,such as architecture,key technologies,scenarios and standardization.To som...This paper proposes a virtual router cluster system based on the separation of the control plane and the data plane from multiple perspectives,such as architecture,key technologies,scenarios and standardization.To some extent,the virtual cluster simplifies network topology and management,achieves automatic conFig.uration and saves the IP address.It is a kind of low-cost expansion method of aggregation equipment port density.展开更多
The heterogeneous network with the separation of the control plane and user plane(C/U) is an evolutionary approach to the fifth generation(5 G) to achieve high system coverage and capacity. To minimize signaling load ...The heterogeneous network with the separation of the control plane and user plane(C/U) is an evolutionary approach to the fifth generation(5 G) to achieve high system coverage and capacity. To minimize signaling load of the core network when there is a macro base station(BS) failure in the control plane, a scheme of transferring the control of small cells under the coverage of the failure macro BS to the neighbor macro BSs is proposed. The average handover rates between small cells related to user mobilities, the extended coverage of the neighboring macro BSs under the constraint of transmitting power and the load balance index of the system are analyzed, based on which the formula of maximizing the handovers processed by macro BSs is constructed and further solved by the convex optimization methods. Simulation results indicate that the proposed scheme can effectively increase the total handovers processed by the macro BSs and thus reduce the signaling load of the core network.展开更多
星载激光测高技术应用于高分辨率光学立体测绘卫星,辅助航天摄影测量以提高卫星几何精度将成为一种重要的技术手段。针对复合测绘这一思路,文章基于有理函数模型(rational function model,RFM)进行立体定位研究。初步建立了高分辨率遥...星载激光测高技术应用于高分辨率光学立体测绘卫星,辅助航天摄影测量以提高卫星几何精度将成为一种重要的技术手段。针对复合测绘这一思路,文章基于有理函数模型(rational function model,RFM)进行立体定位研究。初步建立了高分辨率遥感卫星基于平面控制和高程控制数据分离的区域网平差模型,以天津地区"资源三号"卫星影像作为试验数据,并利用直接前方交会定位模型、RFM系统误差补偿模型、立体区域网平差模型对构建的模型进行精度验证。试验结果表明,基于平面控制和高程控制数据分离的区域网平差可以提高卫星影像的几何定位精度,且精度与其它模型相当,证明了平面高程控制数据分离进行RFM区域网平差的有效性和可行性。展开更多
基金supported by the Collaboration Research on Key Techniques of Future Network between China,Japan and Korea(2010DFB13470)~~
文摘This paper proposes a virtual router cluster system based on the separation of the control plane and the data plane from multiple perspectives,such as architecture,key technologies,scenarios and standardization.To some extent,the virtual cluster simplifies network topology and management,achieves automatic conFig.uration and saves the IP address.It is a kind of low-cost expansion method of aggregation equipment port density.
基金Supported by Basic Research Program of BJUT(No.040000546317525)National Natural Science Foundation of China(No.61571021)+1 种基金Foundation of Beijing Municipal Commission of Education(No.KM201610005004,KM201510005006)Beijing Postdoctoral Research Foundation(No.2018ZZ029)
文摘The heterogeneous network with the separation of the control plane and user plane(C/U) is an evolutionary approach to the fifth generation(5 G) to achieve high system coverage and capacity. To minimize signaling load of the core network when there is a macro base station(BS) failure in the control plane, a scheme of transferring the control of small cells under the coverage of the failure macro BS to the neighbor macro BSs is proposed. The average handover rates between small cells related to user mobilities, the extended coverage of the neighboring macro BSs under the constraint of transmitting power and the load balance index of the system are analyzed, based on which the formula of maximizing the handovers processed by macro BSs is constructed and further solved by the convex optimization methods. Simulation results indicate that the proposed scheme can effectively increase the total handovers processed by the macro BSs and thus reduce the signaling load of the core network.
文摘星载激光测高技术应用于高分辨率光学立体测绘卫星,辅助航天摄影测量以提高卫星几何精度将成为一种重要的技术手段。针对复合测绘这一思路,文章基于有理函数模型(rational function model,RFM)进行立体定位研究。初步建立了高分辨率遥感卫星基于平面控制和高程控制数据分离的区域网平差模型,以天津地区"资源三号"卫星影像作为试验数据,并利用直接前方交会定位模型、RFM系统误差补偿模型、立体区域网平差模型对构建的模型进行精度验证。试验结果表明,基于平面控制和高程控制数据分离的区域网平差可以提高卫星影像的几何定位精度,且精度与其它模型相当,证明了平面高程控制数据分离进行RFM区域网平差的有效性和可行性。