基于对移动通信宽带化的认识,3GPP组织启动了LTE(Long Term Evolution)演进项目。LTE-Advanced作为LTE的进一步演进版本,提出了很多新的关键技术,协作式多点传输(Coordinated Multiple Point(CoMP)Transmission/Reception)技术就是其中...基于对移动通信宽带化的认识,3GPP组织启动了LTE(Long Term Evolution)演进项目。LTE-Advanced作为LTE的进一步演进版本,提出了很多新的关键技术,协作式多点传输(Coordinated Multiple Point(CoMP)Transmission/Reception)技术就是其中之一。该技术通过多个小区之间的联合调度或协作传输,降低邻区干扰,提高用户接收信号质量。文中通过对多小区协作系统传输模型的分析,设计并搭建了多小区协作系统仿真平台,主要包括网络拓扑结构,Wraparound,大/小尺度衰落,链路干扰分析,自适应调制编码,预编码方案。在不同模式下,对系统进行了仿真与分析,结果表明该系统可以有效提高小区平均和小区边缘的频谱效率。展开更多
To further improve delay performance in multi-cell cellular edge computing systems,a new delay-driven joint communication and computing resource BP(backpressure)scheduling algorithm is proposed.Firstly,the mathematica...To further improve delay performance in multi-cell cellular edge computing systems,a new delay-driven joint communication and computing resource BP(backpressure)scheduling algorithm is proposed.Firstly,the mathematical models of the communication delay and computing delay in multi-cell cellular edge computing systems are established and expressed as virtual delay queues.Then,based on the virtual delay models,a novel joint wireless subcarrier and virtual machine resource scheduling algorithm is proposed to stabilize the virtual delay queues in the framework of the BP scheduling principle.Finally,the delay performance of the proposed virtual queue-based BP scheduling algorithm is evaluated via simulation experiments and compared with the traditional queue length-based BP scheduling algorithm.Results show that under the considered simulation parameters,the total delay of the proposed BP scheduling algorithm is always lower than that of the traditional queue length-based BP scheduling algorithm.The percentage of the reduced total delay can be as high as 51.29%when the computing resources are heterogeneously configured.Therefore,compared with the traditional queue length-based BP scheduling algorithms,the proposed virtual delay queue-based BP scheduling algorithm can further reduce delay in multi-cell cellular edge computing systems.展开更多
Coordinated multi-point transmission/reception, CoMP, technique converts the interference signal into the useful information by controlling the interfering signals among adjacent cells. Theoretically, it is a breakthr...Coordinated multi-point transmission/reception, CoMP, technique converts the interference signal into the useful information by controlling the interfering signals among adjacent cells. Theoretically, it is a breakthrough from the traditional interference limited non-cooperative single point transmission system, improving link reliability and enhancing the data rate. CoMP is regarded as one of the most essential and effective techniques in eliminating the inter-cell interference, boosting cell edge throughput and overall system throughput. CoMP technique has obvious advantages in TDD(time division duplexing) cellular mobile system; the necessary channel state information for CoMP can be easily obtained through channel reciprocity property in TDD system. CoMP scheme in TDD system and likely problems are analyzed in this paper, and it is shown by system simulations that the significant gain can be achieved.展开更多
文摘基于对移动通信宽带化的认识,3GPP组织启动了LTE(Long Term Evolution)演进项目。LTE-Advanced作为LTE的进一步演进版本,提出了很多新的关键技术,协作式多点传输(Coordinated Multiple Point(CoMP)Transmission/Reception)技术就是其中之一。该技术通过多个小区之间的联合调度或协作传输,降低邻区干扰,提高用户接收信号质量。文中通过对多小区协作系统传输模型的分析,设计并搭建了多小区协作系统仿真平台,主要包括网络拓扑结构,Wraparound,大/小尺度衰落,链路干扰分析,自适应调制编码,预编码方案。在不同模式下,对系统进行了仿真与分析,结果表明该系统可以有效提高小区平均和小区边缘的频谱效率。
基金The National Natural Science Foundation of China(No.61571111)the Incubation Project of the National Natural Science Foundation of China at Nanjing University of Posts and Telecommunications(No.NY219106)
文摘To further improve delay performance in multi-cell cellular edge computing systems,a new delay-driven joint communication and computing resource BP(backpressure)scheduling algorithm is proposed.Firstly,the mathematical models of the communication delay and computing delay in multi-cell cellular edge computing systems are established and expressed as virtual delay queues.Then,based on the virtual delay models,a novel joint wireless subcarrier and virtual machine resource scheduling algorithm is proposed to stabilize the virtual delay queues in the framework of the BP scheduling principle.Finally,the delay performance of the proposed virtual queue-based BP scheduling algorithm is evaluated via simulation experiments and compared with the traditional queue length-based BP scheduling algorithm.Results show that under the considered simulation parameters,the total delay of the proposed BP scheduling algorithm is always lower than that of the traditional queue length-based BP scheduling algorithm.The percentage of the reduced total delay can be as high as 51.29%when the computing resources are heterogeneously configured.Therefore,compared with the traditional queue length-based BP scheduling algorithms,the proposed virtual delay queue-based BP scheduling algorithm can further reduce delay in multi-cell cellular edge computing systems.
文摘Coordinated multi-point transmission/reception, CoMP, technique converts the interference signal into the useful information by controlling the interfering signals among adjacent cells. Theoretically, it is a breakthrough from the traditional interference limited non-cooperative single point transmission system, improving link reliability and enhancing the data rate. CoMP is regarded as one of the most essential and effective techniques in eliminating the inter-cell interference, boosting cell edge throughput and overall system throughput. CoMP technique has obvious advantages in TDD(time division duplexing) cellular mobile system; the necessary channel state information for CoMP can be easily obtained through channel reciprocity property in TDD system. CoMP scheme in TDD system and likely problems are analyzed in this paper, and it is shown by system simulations that the significant gain can be achieved.
