A simply-differential low-complexity primary synchronization scheme for 3GPP LTE systems

In this paper, downlink primary synchronization for LTE systems is investigated, including time synchronization and sector identification. The proposed scheme exploits the Primary Synchronization Signal which is generated from known Zadoff-Chu sequences. Unlike the conventional schemes, in which time synchronization is first processed then the demodulated OFDM symbols are cross-correlated with the known Zadoff-Chu sequences for sector identification, the proposed scheme simultaneously achieves both tasks. To this aim, the received signal is differentially auto-correlated and compensated with a frequency offset whose value depends on the used Zadoff-Chu sequence. The same metric allows detecting both the symbol timing and the sector identifier. Simulation results, carried in additive white Gaussian noise and Rayleigh multipath channels, show the efficiency and reliability of the proposed primary synchronization scheme. We note that, compared to former methods, the proposed one not only leads to performance enhancement but also realizes a considerable complexity reduction.