Symbol Synchronization Algorithm Based on Pseudo-superimposed Zadoff-Chu in Advanced-LTE

In LTE system, maximum likelihood algorithm based on cyclic prefix is used to accomplish the symbol and slot synchronization. Zadoff-Chu sequences finish frame synchronization and cell search. But in low signal-to-noise ratio AWGN channels and multi-path fading channels, the maximum likelihood peak values are not stable in the right place due to high noise effects, multi-path delays and Doppler effects respectively. In this paper a Pseudo-superimposed Zadoff-Chu sequence has been proposed. Zadoff-Chu sequence is inserted equip-spaced as reference signals in frequency domain, after IFFT reference signals have been transformed into several periodic sequences in time domain. These sequences have good auto-correlation as well as in frequency domain. In contrast to existing synchronization schemes, the proposed architecture has the advantage of better synchronization accuracy and higher data throughput since it doesn't need extra superimposed data in frequency domain or in time domain.