Research And Realization Of Synchronization Technology For OFDM Based On WLAN

OFDM (Orthogonal Frequency Division Multiplexing) is a kind of special multicarrier modulate way, which can combat Inter-Symbol Interference and multi-path fading efficiently and support high rate data transmission with high spectrum efficiency. Now it has become an attractive technology, which will became one of the key technology for next generation mobile communication. Which is also very promising in WLAN(Wireless Local Area Network).Firstly,the background,development, basic principle and application about IEEE802.11a protocol for OFDM based on WLAN are introduced; Then the importance of synchronization is described through introducing influence of sampling frequency error, symbol timing error and carrier wave frequency error. The keys of synchronization research are timing and carrier wave frequency synchronization arithmetic. And do a research about the arithmetic of using local data or utilizing the data's character. By comparing advantage and disadvantage of several arithmetic, give a better synchronization arithm etic for WLAN based on IEEE802.11a.And the hardware design for synchronization arithmetic is also an important aspect, the symbol timing synchronization arithmetic and FFT arithmetic which is 64 point complex number FFT based on block floating point.operation have been contrived by utilizing VHDL based on FPGA.The symbol timing circuit can process sixteen road signals simultaneously. Lastly a digital hardware system has been designed for WLAN, which can be used to finish transmitting and receiving function, including mainly FAGA ,A/D,D/A etc.