Communications is one of the most critical factors in disaster recovery process. However, after a major disaster, existing communications infrastructures may be heavily damaged or even completely unusable. It is neces...Communications is one of the most critical factors in disaster recovery process. However, after a major disaster, existing communications infrastructures may be heavily damaged or even completely unusable. It is necessary that communicationsare to be promptly restored to the disaster area, which is the goal of our national project. The project aims to build three tiers wireless mesh network from remaining wireless access points in order to provide communications services to the disaster area. This work introduces a unique multiple tiers wireless mesh network project. In addition, this work also illustrates merits in optimizing the number of mesh routersin order to achieve the optimum performance by presenting both theoretical and simulation results of a specific scenario of multiple tiers wireless mesh network.展开更多
近年来,北斗导航系统建设逐渐完善,北斗三号区域短报文通信(Reginal Short Message Communication, RSMC)服务已进入行业应用越来越广的关键时期。WiFi信号与北斗三号RSMC出站信号频率接近,在实际使用过程中,2个系统可能存在兼容性问题...近年来,北斗导航系统建设逐渐完善,北斗三号区域短报文通信(Reginal Short Message Communication, RSMC)服务已进入行业应用越来越广的关键时期。WiFi信号与北斗三号RSMC出站信号频率接近,在实际使用过程中,2个系统可能存在兼容性问题。针对WiFi信号干扰对北斗三号RSMC出站信号性能的影响问题,介绍了北斗三号RSMC出站信号的空口特性,分析了WiFi信号对北斗三号RSMC出站信号的带外干扰和带内干扰,基于等效载噪比的分析方法,从载噪比损失方面对干扰的强度做了仿真分析,并给出了改进方法。研究结果为WiFi和北斗区域短报文服务兼容并存提供技术基础。展开更多
文摘Communications is one of the most critical factors in disaster recovery process. However, after a major disaster, existing communications infrastructures may be heavily damaged or even completely unusable. It is necessary that communicationsare to be promptly restored to the disaster area, which is the goal of our national project. The project aims to build three tiers wireless mesh network from remaining wireless access points in order to provide communications services to the disaster area. This work introduces a unique multiple tiers wireless mesh network project. In addition, this work also illustrates merits in optimizing the number of mesh routersin order to achieve the optimum performance by presenting both theoretical and simulation results of a specific scenario of multiple tiers wireless mesh network.
文摘近年来,北斗导航系统建设逐渐完善,北斗三号区域短报文通信(Reginal Short Message Communication, RSMC)服务已进入行业应用越来越广的关键时期。WiFi信号与北斗三号RSMC出站信号频率接近,在实际使用过程中,2个系统可能存在兼容性问题。针对WiFi信号干扰对北斗三号RSMC出站信号性能的影响问题,介绍了北斗三号RSMC出站信号的空口特性,分析了WiFi信号对北斗三号RSMC出站信号的带外干扰和带内干扰,基于等效载噪比的分析方法,从载噪比损失方面对干扰的强度做了仿真分析,并给出了改进方法。研究结果为WiFi和北斗区域短报文服务兼容并存提供技术基础。
