Image Transfer using OFDM System with AWGN and Rayleigh Fading Channel
Keywords:
Channel Equalizer, Adaptive Equalizer, Least Mean Square, Slow Fading, Frequency Selective FadingAbstract
In even promising multicarrier OFDM technologies; the various phenomena such as multipath wave propagation, time dispersion, and fading introduce errors like intersymbol interference (ISI), and other distortions into the signals transmitted over wireless channel. This paper, therefore, investigates the effect of these phenomenon on images transferred through an OFDM based wireless communication system including QPSK modulation, AWGN and Rayleigh fading channels and LMS equalization. The quality of the received image passed through AWGN and Rayleigh fading channels is compared with the original image. At last, the performance improvement in slow Rayleigh fading channel is done using linear equalization with LMS algorithm. The results show significant improvement in error-performance of digital image transmission. It is observed that in AWGN channel, the image is degraded by random noise; and in Rayleigh fading channel, the image is degraded by random noise, block noise, and ISI.
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