Low Complexity MMSE-SQRD Signal Detection Based on Iteration
WU Di, RU Guobao†, GAN Liangcai, YU Xuechun, LIU QiSchool of Electronic Information, Wuhan University, Wuhan 430072, Hubei, China
Aiming at the problem of high computational complexity of Vertical-BLAST (V-BLAST) algorithm in Multiple-Input Multiple-Output-Orthogonal Frequency Division Multiplexing (MIMO-OFDM) system signal detection, this paper first uses Sorted QR Decomposition (SQRD) iterative operation instead of matrix inversion to reduce the computational complexity of the algorithm, and then considering that the algorithm is greatly affected by noise, Minimum Mean Square Error (MMSE) criterion is used to weaken the noise effect. At the same time, in order to reduce the noise and computational complexity, MMSE and SQRD are com-bined, which can not only reduce the noise and computational complexity, but also obtain the sub-optimal detection order, thus improving the detection performance of the MIMO-OFDM system. Finally, the numerical simulation of the MMSE-SQRD detection algorithm is carried out. The results show that the Eb/No of MMSE-SQRD algorithm is 2 dB greater than that of the MMSE algorithm and the computational complexity is under the conditions that and the BER is 10–2. The detection algorithm satisfies the demand of short wave and wideband wireless communication.
Key words:Multiple-Input Multiple-Output-Orthogonal Frequency Division Multiplexing (MIMO-OFDM); Minimum Mean Square Error (MMSE); Sorting Orthogonal-Triangular Decoding (SQRD) algorithm; the MMSE-SQRD algorithm
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