Algorithms of channel SVD estimation in MIMO-OFDM systems: Evaluation and comparison

The previously proposed first-order perturbation-based algorithm and linear constrained least mean square (LMS) based algorithm for channel matrix singular value decomposition (SVD) in multiple - input multiple - output (MIMO) orthogonal frequency division multiplexing (OFDM) systems are evaluated and compared in this paper from orthogonality, signal to noise plus interference ratio (SINR) and bit error rate (BER) view points. Due to approximations made in the perturbation-based algorithm to reduce its complexity, studies show that the estimates of the right and left singular matrices do not become unitary in this algorithm. This phenomenon causes more spatial interference and therefore the perturbation-based algorithm has less performance in comparison with the LMS-based algorithm at high SNRs.