A signal detection algorithm is proposed for the orthogonal frequency division multiplexing (OFDM) sys- tem in the presence of fast time-varying channel. The channel is represented by a piece-wise linear variant mod...A signal detection algorithm is proposed for the orthogonal frequency division multiplexing (OFDM) sys- tem in the presence of fast time-varying channel. The channel is represented by a piece-wise linear variant model with normalized Doppler frequency of less than 0.2. The channel parameters are extracted through ISI/ICI (inter-symbol in- terference/inter-carrier interference) cancellation and circular convolution reconstruction. Meanwhile, an improved OFDM symbol detection algorithm is also proposed based on circular convolution reconstruction. The channel state in- formation in the OFDM symbol duration can be obtained accurately from the adjacent two block pilots in a linear model. The simulation results show that the proposed method can not only track the channel variation, but also promise better performance gain in the OFDM symbol detection. Furthermore, the bit error ratio (BER) is close to the perform- ance with the perfect channel state information.展开更多
基金supported by the National Natural Science Foundation of China(Nos.61032002,71020107027,71001075,and 60902026)Chinese Important National Science & Technology Specific Projects(No.2011ZX03001-007-01)
文摘A signal detection algorithm is proposed for the orthogonal frequency division multiplexing (OFDM) sys- tem in the presence of fast time-varying channel. The channel is represented by a piece-wise linear variant model with normalized Doppler frequency of less than 0.2. The channel parameters are extracted through ISI/ICI (inter-symbol in- terference/inter-carrier interference) cancellation and circular convolution reconstruction. Meanwhile, an improved OFDM symbol detection algorithm is also proposed based on circular convolution reconstruction. The channel state in- formation in the OFDM symbol duration can be obtained accurately from the adjacent two block pilots in a linear model. The simulation results show that the proposed method can not only track the channel variation, but also promise better performance gain in the OFDM symbol detection. Furthermore, the bit error ratio (BER) is close to the perform- ance with the perfect channel state information.