LOW COMPLEXITY FINE TIMING SYNCHRONIZATION METHOD AND SYSTEM FOR STIMI

摘要

A method and system of fine timing synchronization for an OFDM signal. The OFDM signal is coarse timing synchronized, generating a synchronization sequence and a CFR (Channel Frequency Response). The synchronization sequence is removed. A correlation coefficient of the correlation between the CFR applied to a number of carriers and the number of carriers with different window shifts is calculated. The largest window shift corresponding to a downsampling factor is indicated by the lowest correlation coefficient greater than a threshold. The CFR is downsampled by the downsampling factor, and an inverse FFT is performed on the downsampled CFR with a reduced number of calculations reduced by the downsampling factor, transforming the CFR into a CIR. A fine timing synchronization position is determined from the CIR and is utilized by an FFT unit within an OFDM receiver to accurately receive OFDM symbols of the OFDM signal. Application to Satellite Terrestrial interactive Multi-service Infrastructure (STiMi)