Effects of channel estimation in adaptive loading gain of OFDM

Orthogonal Frequency Division Multiplexing (OFDM) modulation scheme is adopted by more and more wireless communication systems to help achieve reliable and high-rate data transmission Wideband wireless system based on OFDM are limited in their performance by the dips in the frequency spectrum of the multipath fading channel.Channel estimation is not only useful for demodulation of the transmitted data but also for implemention of loading scheme for the transmitter,since the performance of OFDM-based system can be augmented by the adaptive loading and power-allocation of the subcarriers. We simulated two kinds of channel estimation schemes and an adaptive loading algorithms, compared the effects of the channel estimation for loading gain. Simulation shows that the loading gain of adaptive algorithm can be improved ulteriorly through better channel estimation.