Research And Implementation Of LTE-A Synchronization And MIMO Detection

Recently, mobile communication technology has been incorporated into people’sdaily life.4G communication system, such as LTE-A, is constantly driving the technicalinnovation in the entire field of wireless communication. With a large number ofemerging technologies joining in, especially multiple input multiple output (MIMO) andOrthogonal Frequency Division Multiplexing (OFDM),4G technical specification isgradually becoming mature.In this paper, Firstly the related technical background of the LTE-A system and thebasic concept of physical layer are briefly introduced. Then the paper focuses on thetwo directions of the cell search in the downlink and the MIMO detection. Cell searchuses the way of secondary synchronization to detect and obtain the detection of the cellinformation by detecting primary synchronization signal (PSS) and secondarysynchronization signal (SSS). The cell search process is an important guarantee of theLTE-A system to establish and maintain communications between the base station (BS)and user equipment (UE), and it’s also the basis of other’s demodulation operation.Synchronization performance directly affects the performance of the LTE-A system, sothe research into cell search process has an extremely important significance. Withoutincreasing transmitting power or transmission bandwidth, system channel’s throughputand quality can be exponentially improved by using MIMO to increase the number oftransmitting antenna and receiving antenna.Therefore，MIMO detection technology hasalso becoming one of researching hotspots currently.Matlab simulation, hardware architecture design and FPGA implementation havebeen done in cell search module. The algorithm simulation platform of the cell searchincluding PSS detection, SSS detection, the frequency offset estimation and CPdetection process, etc, has been builded with matlab firstly. An improved CP detectionalgorithm is proposed in this paper, which uses the method of sliding correlation toincrease the measuring accuracy of CP detection. While a SSS sequence detectionalgorithm is improved to reduce the amount of calculation of the SSS detection.Then,the paper designs and optimizes the hardware structure of Cell Search module according to the project requirements. In this article, Low-passed filter is replaced by CIC filterbank to reduce the resource consumption; the folding structural is used in PSS detection;CP detection module is improved by Sliding correlation; the decimal frequency offsetand PSS fine synchronous head are estimated together by multiple CP mode; etc. Thechannel estimation and equalization has been finished by using matlab platform forMIMO detection.Then the Pipeline structure of the LS channel estimation module andZF equalization module are designed on the basic of the project requirement.Finally, all of the hardware architectures are implemented on Xilinx’s Kintex-7series FPGA chip XC7K325T.