Research And Implementation Of Time-domain Synchronization Algorithm In Burst OFDM System

Orthogonal frequency division multiplexing(OFDM) is a preferred data modulationtechnique for achieving high spectral efficiency and combating fading in high data-ratewireless communication. While the OFDM data is transmitted as one symbol, so in order toreduce the effect of inter-symbol interference(ISI), the correct start of symbol should be gotfrom the received signals to. And the high spectral efficiency and the robust transmission ofOFDM system are based on the orthogonal properties of the subcarriers, so if frequencyoffset is generated, the orthogonal properties of subcarriers will be lost and that will causeinter-channel interference(ICI). The ISI and ICI resulting from synchronizational offset maylead to the deterioration of the bit error rate(BER) performance of OFDM system or evencommunication failure. Therefore, the performance of synchronization exerts a directinfluence on data transmission in OFDM system. In this paper, the algorithm and hardwaredesign of synchronization in burst OFDM system are studied and the scheme of them aregiven.First, the basic principle of OFDM system is introduced in detail, and the effect offrequency offset, timing offset and sampling offset on OFDM system are discussed througha detailed theoretical analysis and simulation. Then the algorithms of frame detection,symbol timing synchronization and the estimation and correction of frequency offset areanalysed, and an algorithmic scheme of the whole synchronization in time domain based onthe training series’s delayed auto-correlation is proposed. The BER performance is proved tosatisfy the require of communication system after simulation and verification. Compared toother synchronization scheme it needs much less arithmetic. At last, the hardware design andoptimization of the synchronization scheme proposed above are given, and the hardware costis reduced apparently by multiplexing of some submodules, recurrence operation,simplification and approximation of some formulas. The area and power comsumption are analyzed through the EDA tool and the synthesized results show that the area and powerconsumption of the design are decreased by over30percent compared to related references.