Low Complexity Parallel Symbol Detection for OTFS Modulation

Abstract

This article proposes a novel low-complexity parallel message passing (PMP) detection scheme for orthogonal time-frequency space (OTFS) modulation technology. The traditional message passing (MP) scheme is to detect message symbols individually. Due to a large number of loop nesting calculations in the process of MP symbol detection, the overall calculation time of the detection is relatively long, and its efficiency is lower. In the PMP scheme, all symbols are detected synchronously. This scheme optimizes the structure of the symbol detection algorithm, and can significantly shorten the detection time. A non-sparse channel coefficient matrix representation is revealed by us to achieve parallel detection. We derive the expression for the PMP algorithm, and then simulate the algorithm by two different mapping methods. Furthermore, we explore the symbol detection time required by the PMP algorithm in continuous multi-frame data and single-frame data transmission modes. The data shows that the performance of the PMP algorithm is more prominent when multiple data frames are transmitted continuously.