Simplified Two-Dimensional Non-Uniform Constellation Demapping Algorithm for ATSC3.0

Non-uniform constellations (NUCs) have been adopted in digital broadcasting systems to reduce the shapping gap to the Shannon theoretical limit. Among NUCs, two-dimensional NUCs (2D-NUCs) provide better performance than one-dimensional NUCs (1D-NUCs), but bring higher complexity at the receiver. This paper proposes a simplified demapping algorithm for 2D-NUCs from ATSC3.0 (Advanced Television Systems Committee 3rd Generation), for low to medium code rates. Theoretical analysis and simulation results prove that the complexity of the proposed simplified demapper is reduced while the performance degradation is negligible, compared with the traditional demapper.