Adaptive ICI cancellation for OFDM communication systems in time-varying multipath fading channels

• Main Authors: Wen-Sheng Hou, 侯文生
• Other Authors: Bor-Sen Chen
• Format: Others
• Language: en_US
• Published: 2000
• Online Access: http://ndltd.ncl.edu.tw/handle/42339645404553359860

博士 === 國立清華大學 === 電機工程學系 === 89 === In orthogonal frequency division multiplexing (OFDM) systems, a loss of the subchannel orthogonality due to the time-varying multipath fading leads to interchannel interference (ICI). In this study, we address the ICI suppression for multicarrier detection with less noise enhancement by using a parallel canceling scheme of the frequency-domain equalization technique. In this technique, the equalization of the received OFDM signal is achieved by using the assumption that the channel impulse response (CIR) varies in a linear fashion during a block period. In order to avoid performance deterioration due to unreliable initial estimation in the parallel cancellation scheme, a cost function with proper weighting of the design criterion is introduced to improve the performance of the proposed equalizer. The proposed equalizer consists of a prefilter and an ICI cancellation filter. Each filter performs different functions. The prefilter compensates the multiplicative distortion. The ICI cancellation filter is proposed to remove the effects of ICI by a parallel cancellation scheme. Finally, the performance of the proposed equalizer is analyzed and compared with that of other equalizers.