基于最佳虚拟网关的认知SCMA系统

Cognitive SCMA System Based on Optimal Virtual Gateway

在5G的海量机器类通信(mMTC)场景下,为解决频谱资源不足和网络拥塞问题,本文提出一种基于最佳虚拟网关的认知SCMA系统模型.该模型根据QoS要求和地理位置把机器类通信设备(MTCD)分成独立的集群,在每个集群中通过认知无线电技术感知可能提供空闲频谱资源的LTE用户,定义为虚拟网关,再根据满意度最大规则选出最佳虚拟网关,将最佳虚拟网关提供的频谱资源分为多个子载波组,并设计MTCD与子载波组的最优匹配算法,MTCD以SCMA(稀疏码多址接入Sparse Code Multiple Access)方式接入网络.仿真结果表明所提方案可有效提高系统的吞吐量.

In the massive machine type communication(mMTC)scenario of 5G,in order to solve the problem of insufficient spectrum resources and imperfect resource allocation,this paper proposes a cognitive SCMA system model based on the best virtual gateway.This model divides machine type communication devices(MTCDs)into independent clusters based on QoS requirements and geographic location.In each cluster,cognitive radio technology is used to perceive LTE(Long Time Evolution)users who may provide idle spectrum resources,which are defined as virtual gateways.Then the best virtual gateway is selected according to the rule of maximum satisfaction.The spectrum provided by the best virtual gateway is divided into multiple subcarrier groups,and design an optimal matching algorithm between MTCDs and subcarrier groups.MTCDs access the network through the SCMA mode.Simulation results show that the proposed scheme can effectively improve the throughput of the system.