基于天基干扰绘图的星地一体化系统频谱共享研究

Study of spectrum sharing in integrated satellite-terrestrial system based on space-based interference cartography

针对未来星地一体化系统中新入低轨道地球卫星(LEO)组件的用频需求和现任地面组件聚合干扰影响的问题,面向天基认知系统提出频谱感知和频谱数据库辅助的交织模式频谱共享方案。首先,针对低轨认知系统节点稀疏分布属性对频谱感知和干扰绘图带来的负面影响,提出“认知节点位置”概念。其次,研究低轨认知系统的双门限混合频谱感知和干扰绘图的机制,构建频谱数据库。最后,面向多状态虚拟网络模型,提出卫星组件上行频谱共享方案,实现LEO组件和地面组件之间的同频共存工作。仿真结果表明,所提双门限混合感知和干扰绘图能以较低密度的低轨认知节点实现高可靠性的频谱空间态势认知;所提基于频谱数据库和交织模式的LEO组件协作接入方案可以实现与地面组件的频谱共享,且不会显著增加LEO组件的端到端时延。

To deal with the spectrum demand of new low earth orbit satellite(LEO)communication component and the aggregate interference generated by incumbent terrestrial component in future integrated satellite-terrestrial system,a novel space-borne spectrum-sensing(SS)and spectrum-database assisted spectrum-sharing scheme with interweave model for LEO cognitive system was proposed.Firstly,considering the adverse impact of the sparse distribution of LEO cognitive node(CN)on SS and interference cartography(IC),the concept of cognitive node position was put forward.Secondly,the spectrum-DB was built based on dual-threshold hybrid SS and IC with LEO cognitive system.Finally,a spectrum-sharing scheme with multi-state virtual network(MSVN)was designed,which could make the coexistence be-tween terrestrial component and uplink of LEO component available.Simulation results indicate that the spec-trum-database approach based on the proposed dual-threshold hybrid SS and IC can support the spectrum awareness of high reliability with relatively low-density LEO CN,and that the proposed cooperative access scheme based on spec-trum-database and interweave model for LEO component can share spectrum with terrestrial one,but not significantly increase the end-to-end delay of LEO component.