Research And Simulation Of Uplink AMC Technology Based On LTE System

In response to the challenges of broadband access technology and the high growth of wireless data communications,the 3GPP developed the LTE Project based on the third-generation broadband code division multiple access system.LTE is designed to create a new generation of wireless communication system that comprehensively supports high-performance data services with flexible bandwidth,high speed,high channel capacity,low delay and low cost.For this reason,LTE system changes the system architecture and takes Orthogonal Frequency Division Multiplexing(Orthogonal Frequency Division Multiplexing)and MIMO(Multiple Input Multiple Output,multi-antenna transceiver technology)as core technologies.At the same time,Hybrid automatic repeat request(Hybrid automatic repeat request)fault tolerance technology and AMC(Adaptive Modulation and Coding)technology are also adopted to further improve system performance and stability.Using AMC technology in LTE wireless communication system can not only resist the time-varying of the channel,but also overcome the impact of average path loss,slow decline and fast decline.The basic theory of AMC technology is to select the most appropriate up-link and down-link modulation and coding method according to the user's instantaneous channel quality status and current resources,so as to achieve the highest data throughput rate.The research in this thesis is carried out when the traffic level of a single UE is low at the far up-link point and MCS is too slow to adjust for multiple up-link transmission tests.It is found that the existing algorithm has some unreasonable parameters and process settings based on AMC procedure,which leads to poor traffic.Therefore,an optimization algorithm based on MAC was designed for the defects of existing algorithm.SINR and BLER were combined to adjust the MCS,and the process and parameters were properly configured and processed.Finally,the performance advantages of the algorithm were verified by building a simulation platform.