Mitigation of Signal Interference by Positioning FFT Window for OFDMA System

In today’s generation, there is a need for achieving high-data rate to compete with the standard applications like OFDMA. The high speed depends on how efficiently the spectrum is being used to transmit the data from transmitter to the receiver. Due to the time-dispersive nature of the fast fading channels, the signal may get faded when reaching the receiver. The signal formed by group of symbols travels via multiple paths to reach the receiver. The fading caused by multipath propagation is called the multipath fading. To reduce the signal interference, many equalization technique algorithms have been proposed [1]. Apart from equalization algorithms, FFT operation window can be positioned at the downlink module of OFDMA system ensuring all the symbols have been received at the receiver to reduce the interference and increase the SNR. ModelSim 10.2 and MATLAB have been used to simulate and compare the results. The simulation results of the proposed method show 4.8% significant improvement of SNR.

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