Study and Implement in FPGA of DAGC in OFDM System
Yang Wan-lin · Modern Electronics Technique · 2009
The precision of IDFT/DFT is important for baseband demodulation in OFDM system is introduced.Based on analyzing the influence of input power on the precision of fixed DFT,DAGC technique is adopted ahead of DFT to resolve the aggravation of DFT output SNR,which is brought in by the large dynamic range of input signal.The analysis of theory,the result by simulating in Matlab and implementing in FPGA indicate that the proposed method is feasible,real time and simple,which can make the output SNR of DFT in the optimal range on request of base band demodulation in OFDM system.In the case of large input power,the proposed method with DAGC technique achieves a DFT output SNR increase of 24 dB by system simulation,comparing with the classic method which lessens the overflow error of DFT.