The Research On Synchronization Technology Of Long Term Evolution Downlink

LTE as lead the direction of future communication development, OFDM technology with high spectrum efficiency, high data transfer rate and the advantages of resistance to multipath interference, has become the key technologies of LTE downlink, Multicarrier characteristics of OFDM technology, however, also make the LTE system becomes more sensitive, As a result, the influence of the synchronization performance of LTE system at the receiving end is particularly important, This article mainly through OFDM synchronization algorithm of two aspects of timing synchronization and carrier frequency offset estimation, to research of the synchronization performance of LTE downlink link.First, this thesis introduces the historical background and developing process of LTE, domestic and foreign development present situation, research purpose and meaning, Introduces the principle, the basic principle of OFDM synchronization and synchronization performance will affect the performance of the system.Secondly, this thesis mainly studied the classical algorithms based on training sequence synchronization algorithm SC algorithm, Minn algorithm and Park algorithm, and the synchronization algorithm based on cyclic prefix is classic algorithm ML algorithm. Using the simulation results, analysis the advantages and disadvantages of the existence of several classical algorithms. Mainly puts forward a new synchronization algorithm based on training sequences, improved a synchronization algorithm based on cyclic prefix, Through the simulation analysis, two new proposed algorithm synchronization performance than the classical algorithm of synchronization performance are improved.Finally, this thesis studied and analyzed the OFDM synchronization fast algorithm, introduced using the symmetric conjugate fast training symbol synchronization algorithm and the use of repeated symmetric conjugate training symbol synchronization fast algorithm, and on the basis of two kinds of fast synchronization algorithm, the improved measures are put forward.Through the simulation analysis, the improved algorithm performance is larger than in the past.