Reduced Complexity Stack-Based Limited Tree Searching Algorithm for V-BLAST Systems

The vertical Bell Labs layered space-time (V-BLAST) architecture is considered as an efficient technology for achieving high spectral efficiency in a rich-scattering environment. In this paper, we propose a computationally efficient near-optimal detection algorithm for V-BLAST systems. The proposed scheme employs QR decomposition (QRD) of the channel matrix and stack-based limited tree searching method. To reduce computational complexity, especially in low SNRs, the number of branches required for the extension of the tree structure is conditionally chosen according to the channel condition and SNR. The new algorithm requires a fraction of an effort to achieve a near-optimal performance in comparison with other near-optimal detection schemes