Reduced-complexity performance-lossless (quasi-)maximum-likelihood detectors for S-QAM modulated MIMO systems

Abstract

Proposed is a simplified branch metric calculation method for the (quasi-)maximum-likelihood (ML) detector for square quadrature amplitude modulation (S-QAM) aided multiple-input and multipleoutput (MIMO) multiplexing systems while retaining identical performance to the respective one. The key idea of the proposed method is to exploit the geometric property of the S-QAM constellation, so that the branch metric calculation for all the constellation points can be calculated in an incremental way from any constellation point mainly through addition and bit-shift, thus significantly reducing the computational complexity of the ML detector. © 2013 The Institution of Engineering and Technology.