Efficient Spread Pilot Based Synchronization Method for Linear Precoded OFDM Systems

In this paper, we propose a novel and efficient joint carrier and sampling frequency offset estimation algorithm based on 2D spread pilots for digital video broadcasting (DVB) systems. The first advantage of the proposed algorithm is the use of the same pilot symbols for both channel estimation and synchronization. A gain in term of spectral efficiency is obtained compared to the DVB-T/H system for which different pilot symbols are defined for channel estimation and synchronization. The second advantage is that all the subcarriers convey a part of the pilot information contrary to the DVB-T/H system where only a few pilot subcarriers are used for CFO and SFO estimations. Consequently, the proposed system provides a diversity gain for both CFO and SFO estimations. Finally, the performance evaluated over a realistic channel model shows the efficiency of our technique which turns out to be a promising frequency synchronization approach for future DVB systems.