Design of Circular Structured One-dimensional Non-uniform Constellations with Better Performace

Adopting higher modulation order and spacing constellation symbols non-uniformly are two strategies in modern communication systems to meet increasing demand for data volume and to reduce the gap between bit-interleaved coded modulation (WM) capacity and Shannon limit. This paper proposes a certain circular structured constraint strategy to design one dimensional non-uniform constellations (1D-NUCs) with remarkable performance. This strategy also ensures low demapping complexity (especially for high order NUCs) which benefits applications in power-limited systems. Meanwhile, a computable expression of BICM capacity based on polar coordinates is derived to revise constellation designing scheme with the proposed constraint strategy. Through the revised designing scheme, a set of circular structured 1D-NUCs with order of 1024 are obtained and testified having the ability to provide higher shaping gain than the ones adopted by ATSC 3.0 with low complexity.