Summary: | 碩士 === 國立交通大學 === 電信工程系所 === 95 === The channel variation due to vehicle mobility produces frequency selective fading among OFDM symbols which makes the traditional one-tap equalizer can not be utilized. Moreover, the orthogonal property of OFDM subcarriers is destroyed and OFDM symbol experiences inter-carrier interference (ICI) that severely degrades the performance in high vehicle mobility environment. To reduce the problem, an iterative group based ICI cancellation method which applies sphere decoding and list sphere decoding (LSD) is proposed. At the receiver, subcarriers are partitioned into several groups, each group uses SD or LSD to generate the message information and pass it to other groups for ICI cancellation. The grouping procedure is used to reduce the computation complexity of the SD and LSD, and ICI cancellation procedure is used to make BER performance better.
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