超密集网络下行传输局部按需协作的功率分配方法

Power Allocation Method for On-demand Local Cooperation in Downlink Transmission of Ultra Dense Wireless Network

针对超密集网络的下行传输,分析研究了频谱效率和功率分配方案,并基于对性能和复杂度的综合考量,提出了密集部署接入点(Access Point,AP)基于部分用户迫零和按需进行局部协作的功率分配方法。先假设每个AP知道用户的位置信息,且仅服务其附近的用户,利用迫零准则消除所服务用户之间的干扰,即部分用户迫零。功率分配则基于信道大尺度衰落进行。但可能存在无法满足部分用户最低通信需求的情况,需针对这部分用户形成局部协作簇,并对功率分配进行重新优化。仿真结果显示,该算法在避免了功率资源全局优化带来的高计算复杂度问题的同时,也保证了系统性能。

For the downlink transmission of ultra-dense wireless networks,this paper analyzes and studies the spectral efficiency and power allocation scheme,and based on the comprehensive consideration of performance and complexity,proposes a power allocation method for a single AP(Access Point)based on partial user zero-forcing and local cooperation on demand.First,it is assumed that each AP knows the location information of users,and only serves users nearby.Then,it uses the zero-forcing criterion to eliminate the interference among the served users,that is,some users are zero-forcing.After precoding,the power is allocated according to the large-scale fading factor of the channel,but some users in the ultra-dense wireless network cannot meet the minimum communication requirements.Therefore,it is necessary to form local cooperative clusters for these users,and use the optimization method to reallocate the power.Simulation results indicate that this algorithm not only avoids the high computational complexity caused by the global optimization of power resources,but also ensures the system performance.