| Orthogonal frequency division multiplexing (OFDM) has advantages such as robustness against multipath delay spread, high bandwidth efficiency and simple hardware implementation which has attracted a lot of attentions in recent years. It has broad applications in the fields of digital audio broadcasting, digital television and wireless local area networks. However, one of the drawbacks of OFDM is that it is sensitive to synchronization offset. The ideal system performance can be obtained only if the precision of the frequency/timing synchronization is higher. This problem is researched in this paper.In this paper, we first introduce the basic principles of OFDM, then we analyze and research the reason of carrier frequency offset as well as the influence on the system. Bases on this analysis, we deeply research and simulate the algorithms of timing and frequency synchronization in OFDM from two aspects (bases on the pilot symbols method and non-data-aided (blind) method).Both the theroy analysis and simulation results show that although the blind algorithm has high bandwidth efficiency and synchronization precise, yet the computational complexity is rather high, which is difficult to realize in practice. In the end the algorithms involved are compared and concluded. |
PDF Full Text Request