Complexity analysis of matrix decomposition algorithms for linear MIMO detection

MIMO is a key technology to achieve the thousand fold data rate requirement for next generation communication system. The linear MIMO system is becoming more attractive as the antenna dimension is increasing and due to the advent of advanced MIMO techniques, such as massive MIMO. In this paper, we presented the complexity analysis of matrix decomposition algorithm that is needed to invert the Gramian matrix of a linear MIMO detector. We analyzed the complexity of four different matrix decomposition in this work, two variants of QR, Cholesky and LDL decomposition. The analysis is done for three different antenna configurations. We also presented the detection method using the decomposition algorithms and provided the hard output simulation results.