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.