
Low‐complexity MMSE‐based integrated equalisation for MIMO systems with HARQ
Author(s) -
Park S.
Publication year - 2017
Publication title -
electronics letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.375
H-Index - 146
eISSN - 1350-911X
pISSN - 0013-5194
DOI - 10.1049/el.2017.0400
Subject(s) - minimum mean square error , mimo , computational complexity theory , algorithm , computer science , hybrid automatic repeat request , mathematics , control theory (sociology) , statistics , telecommunications , channel (broadcasting) , telecommunications link , artificial intelligence , control (management) , estimator
Low‐complexity minimum‐mean‐square error (MMSE)‐based integrated equalisation (IEQ) for multiple‐input multiple‐output (MIMO) systems with hybrid automatic repeat request (HARQ) is proposed. In the proposed MMSE‐based IEQ, the calculations of the MMSE filtering vector for each symbol in the conventional MMSE‐based IEQ are newly derived in a simplified form. This not only allows the proposed IEQ to have the same MMSE filtering vector to the conventional IEQ but it also allows the matrix size to be inverted and the number of matrix inversions are also significantly decreased. Therefore, without sacrificing the error performance, the proposed IEQ requires a significantly lower computational complexity than the conventional IEQ as the number of inputs increases. Furthermore, the proposed IEQ can outperform the MMSE‐based iterative equalisation with the log‐likelihood ratio‐level combining in terms of both error performance and computational complexity.