Performance Evaluation of Equalizers and Different Diversity Techniques using OFDM

In this paper, we analyzed the performance of different diversity techniques, which can be easily applied with orthogonal frequency division multiplexing (OFDM) systems with different equalizing methods. Orthogonal frequency division multiplexing is well known to be a useful technique for high rate data transmission over a frequency selective fading channel. However, for coherent detection of OFDM signals, fading compensation techniques are required to mitigate amplitude and phase distortions due to the multi-path channel fading. The fading compensation technique becomes even more crucial when QAM is used for OFDM systems. A channel estimation technique using periodically inserted pilot symbols in the data stream is well known to provide a reliable way to mitigate the distortions.