Research And Implementation Of Symbol Timing Synchronization In UFMC System

As one of the 5G candidate waveforms,UFMC has the advantages of strong out-band rejection,good robustness against time-frequency offset,supporting for selection of CP,high utilization rate of fragment spectrum and so on,which make it become the most competitive multi-carrier technique among many other candidate waveforms.However,UFMC as a kind of multi-carrier technique,whose system performance must be affected by timing offset.In order to reduce the impact of timing offset on UFMC system performance,this thesis proposes a timing offset estimation method for receiving signals to achieve the symbol timing synchronization of UFMC system.Thus,this thesis makes an in-depth study about symbol timing synchronization algorithm in UFMC system,and the main work can be summarized as follows:Firstly,this thesis gives the detailed mathematical derivation process of UFMC system and introduces the key technologies in the system.In addition,the influence of timing offset on UFMC system performance is analyzed and the analysis results show that the timing offset will result in the reduction of the system SINR.Decreasing,it can be seen that the importance of symbol timing synchronization algorithm for UFMC system.Besides,the classical symbol timing synchronization algorithm in UFMC system has the disadvantages of low utilization of training symbols,low accuracy of timing estimation and poor anti-noise performance.In order to solve this problems,this thesis adopts the method of inserting ZC sequence on even carrier,and inserting 0 on odd carrier to generate symbol which has two identical data segments,and redesign the symbol according to the characteristics which is the corresponding addition of data segment in the header and end with L-1 length is equal to the length in the middle of L-1 length to generate new training symbol.Then using the new training symbol structure,the corresponding timing measure function formula can be given to complete the improvement of algorithm.The improvement of training symbol utilization rate and the elimination of the platform effect of the improved algorithm this thesis proposed enhances the anti-noise performance and improves the accuracy of the algorithm,respectively.Finally,the UFMC receiver is built on the software radio platform,and the symbol timing synchronization algorithm proposed in this thesis is designed and implemented at the same time.Under the normal working conditions of the transmitter,the corresponding test is used to verify the feasibility and reliability of the improved algorithm proposed in this thesis.The test results show that the symbol timing synchronization algorithm proposed in this thesis can show good performance in practical applications and can be verified with theoretical simulation results.