Research On Channel Estimation And Synchronization Algorithm In Direct Detection FOFDM System

FOFDM get extensive attention from communications industry for its high spectrum efficiency and simple digital design.Compared with OFDM,the channel spacing of FOFDM is half as OFDM.Compared with the DDO-OFDM system,DDO-FOFDM system with same simple structure is easy to implement,but it reduces the complexity of digital design.This paper will make a further research about how to accurately fulfill the synchronization and the channel estimation of FOFDM symbol.The research results are as follows:The idea about OFDM symbols as the training sequence used in FOFDM system is researched and put forward.In FOFDM system,training sequence is OFDM symbol,using cross-correlation between a local training sequence and received signal to find out the starting position of the training sequence,so as to achieve synchronization effect.The interpolation about the method of channel estimation is researched and put forward.About channel estimation,as a result of OFDM symbols use as training sequence in this paper,and transmission of data is FOFDM symbols,so the OFDM symbol channel spacing is twice as FOFDM symbol.A interpolation is made about channel response for training sequence,each with a value between two frequency points,finally get FOFDM symbol corresponding channel response.For putting forward ideas,making a simulation and experiment,which verify the validity of the idea.