基于基站频谱借用的协作通信网负载均衡机制

Load Balancing Based on Spectrum Sensing by Station in Cooperative Networks

针对现有基于信道借用负载均衡技术需要基站间信息的频繁交互而增加网络信令开销和能量消耗问题,提出一种将频谱感知技术应用于协作通信网络负载均衡的机制。该机制中基站利用能量检测频谱感知技术实时感知网络的频谱空洞,生成可借用的频谱集合。基站出现资源耗尽时调用可借用频谱集合,选择目标用户,并根据目标用户是否有协作给用户借用频谱。若用户不存在协作,则以最大化联合频谱空闲率和频谱质量的效用函数为目标给用户借用直接链路的频谱;若用户存在协作,则在直接链路选择的基础上,以最大化效用函数进行频谱和协作用户的联合选择。仿真表明该机制在网络公平性性能上提升了0.5%~1.1%,在容量性能上提升了0.61%~1.4%,在资源利用率上提升了0.63%~1.4%。

Aiming at the problem,the existing load balancing technology based on channel borrowing requires frequent interaction between base stations to increase network signaling overhead and energy consumption. A mechanism which applies spectrum sensing technology was proposed to Cooperative networks based on Load Balancing. In the designed mechanism,the base station utilizes the spectrum sensing technology to detect the spectrum holes of the network,and then generates the available spectrum set. Once the spectrum resource of base station is exhausted,the base station will invoke the available spectrum set,and choose the target borrowing user.Then borrow spectrum to the user according to the conditions that whether the target borrowing user has cooperation in the base station. If the target borrowing user does not have cooperation in the serving cell,the bandwidth of the direct link is borrowed from the user,which can maximize the utility function of the combined spectrum idle rate and spectral quality. If the user has cooperative communication in the cell,based on the spectrum selection of direct communication link,the objective of the spectrum borrowing is to maximize the utility by choosing the optimal available spectrum and cooperative partner. Simulation shows that the mechanism in the network fairness performance increased by 0. 5% to 1. 1%,in the capacity of the performance increased by 0. 61% to 1. 4%,in the resource utilization rate increased by 0. 63% to 1. 4%.