Designing Low-Complexity Detectors Based on Seysen´s Algorithm

Lattice reduction (LR) has been applied to linear equalizers and decision feedback equalizers to improve their performance. Recently, Seysen´s algorithm (SA) has been proposed as an alternative LR method to the well-documented LLL algorithm. In this paper, we first provide a tree-search implementation method of SA which enables flexible performance-complexity trade-offs. Based on this tree structure, SA-aided hard-output and soft-output detectors are proposed to enhance performance. The diversity and complexity of the proposed methods are also studied. Thorough comparisons of SA and other LR algorithms are provided. Our analysis of complexity and numerical simulations provide insights that are useful to system designers.