Parallel Realization Of Cell Search Algorithm Of TD-LTE Based On SB3500

Compared with the traditional mobile communication system,LTE can provide a peak downlink rate over 100Mbps.In addition,LTE has low system delay and supports high-speed mobility of the UE.After the UE is powered on,the first step is to select the appropriate cell to access network,and we call this step is cell search.After this step,the subsequent communication process could be carried out smoothly.Multi-core digital signal processor?DSP?and System-on-chip?SoC?are widely used in communication systems because of their flexible software compilation and the advantages of being able to handle large amounts of data.Therefore,it is of great significance to study the cell search algorithm of LTE system on multi-core DSP chips.The SB3500 baseband processor is a multi-core DSP processor capable of running the wireless protocols required by any common multi-mode,multi-function mobile platform.It's three four-thread DSP cores are capable of efficiently performing physical layer tasks.This article mainly studies the architecture of the SB3500 processor platform and the implementation of the LTE cell search module under this platform.This paper first introduces the basic concepts and key technologies of physical layer in LTE cell search,including synchronization algorithm of primary synchronization signal?PSS?,cyclic prefix?CP?decision algorithm,frequency offset estimation algorithm,and synchronization algorithm of secondary synchronization signal?SSS?.During the PSS synchronization,the received signal is first filtered down by 16 times,and then the filtered data is quickly correlated with the three local synchronization signals respectively to find the cell ID of physical layer--N_ID^?2?.Then we use the location of the synchronized PSS to determine the CP type.In the frequency offset estimation algorithm,this thesis uses the PSS found in the synchronization process of the primary synchronization signal to determine the frequency offset by solving the angle offset of the PSS.In the synchronization of the SSS,we can decouple the scrambling sequences which have been obtained by separating the odd sequence and the even sequence,respectively.Finally,we verify the feasibility of the algorithm on the MATLAB platform.Secondly we briefly introduce features and performance characteristics of SB3500 chip,as well as the advantages of the processing chip.At the same time,a detailed introduction to its software development principles and development process is given.Finally,we introduce the process of using SB3500 chip to fulfill the parallel implementation of the cell search.The data shows that the performance of the cell search algorithm based on this platform has been obviously improved.