Research And Realization On OFDM Synchronization Techniques

In this paper, we first introduce the history and development of digital audio broadcasting and present a design and implementation of synchronization for OFDM(orthogonal frequency-division multiplexing) system based on Eureka147DAB standard. We describe the synchronization technique in several keys including symbol timing, carrier frequency offset estimation and sampling clock offset estimation. For symbol timing synchronization techniques, we first study the interference caused by coarse symbol timing offset, fine symbol timing offset, sampling clock offset, and then analyze some typical algorithms. After indicated their deficient, some new algorithms for Eureka147DAB are presented. For carrier frequency offset synchronization techniques, some effect caused by fine carrier frequency offset and integer carrier frequency offset have been pointed out through simulation and analysis, and a new fine carrier recovery algorithm is proposed. For sampling clock synchronization, the effects of sampling clock offset on system performance are analyzed with computer simulation results. Different from the previous literatures, a new method for sampling clock offset estimation is introduced. Above all, through a comprehensive description and Matlab simulation, this paper introduces a whole synchronization scheme suit for Eureka147DAB, and discusses the hardware synchronizer using FPGA and DSP on general hardware platforms.