Multiple-input multiple-output(MIMO)technology has been promoted to achieve high-speed data transmission.Compared to the orthogonal frequency division multiplexing(OFDM)based MIMO systems,the single-carrier scheme(SC)...Multiple-input multiple-output(MIMO)technology has been promoted to achieve high-speed data transmission.Compared to the orthogonal frequency division multiplexing(OFDM)based MIMO systems,the single-carrier scheme(SC)has attracted lots of attention due to its low peak-to-average ratio(PAPR)feature and is quite suitable for longdistance transmission.However,one of the significant challenges of SC-MIMO systems is the vast complexity of channel equalization and signal detection,especially for the inter-symbol interference(ISI)caused by the multipath channel.The single carrier frequency domain equalization-based minimum mean square error(SCFDE-MMSE)algorithm is proved to achieve satisfying performance.However,it involves large numbers of DFTs and large-scale matrix inversions,which is unacceptable for practical systems.In this paper,a low-complexity SCFDE-MMSE(LCSCFDE-MMSE)algorithm is proposed.Firstly,the characteristics of cyclic matrix and DFT cyclic shift are combined to reduce the number of DFTs.Secondly,SCFDE is transformed into a symbol-wise manner to avoid large-scale matrix inversions.Finally,a frequency-domain interpolation method is proposed to reduce the number of small-scale matrix inversions further.According to the evaluation results,the proposed LC-SCFDE-MMSE reduces the complexity of the traditional SCFDE-MMSE algorithm by more than one order of magnitude with less than 0.1 dB performance loss.展开更多
基金supported by National Natural Science Foundation of China(Grant Number:62371099).
文摘Multiple-input multiple-output(MIMO)technology has been promoted to achieve high-speed data transmission.Compared to the orthogonal frequency division multiplexing(OFDM)based MIMO systems,the single-carrier scheme(SC)has attracted lots of attention due to its low peak-to-average ratio(PAPR)feature and is quite suitable for longdistance transmission.However,one of the significant challenges of SC-MIMO systems is the vast complexity of channel equalization and signal detection,especially for the inter-symbol interference(ISI)caused by the multipath channel.The single carrier frequency domain equalization-based minimum mean square error(SCFDE-MMSE)algorithm is proved to achieve satisfying performance.However,it involves large numbers of DFTs and large-scale matrix inversions,which is unacceptable for practical systems.In this paper,a low-complexity SCFDE-MMSE(LCSCFDE-MMSE)algorithm is proposed.Firstly,the characteristics of cyclic matrix and DFT cyclic shift are combined to reduce the number of DFTs.Secondly,SCFDE is transformed into a symbol-wise manner to avoid large-scale matrix inversions.Finally,a frequency-domain interpolation method is proposed to reduce the number of small-scale matrix inversions further.According to the evaluation results,the proposed LC-SCFDE-MMSE reduces the complexity of the traditional SCFDE-MMSE algorithm by more than one order of magnitude with less than 0.1 dB performance loss.
