Constellation Evolution Mother Codebook Design in SCMA

Abstract Sparse code multiple access (SCMA) is an emerging technology developed to meet the requirements of 5G and 6G communications and improve the spectral efficiency of systems. The key behind SCMA technology is the design of its codebook method, particularly the design of the mother codebook method, which forms the basis of excellent user codebook design. Considering the limitations of existing mother codebook methods, a constellation evolution mother codebook design method is proposed here. Odd and even constellations are derived using the proposed method, and a multi-dimensional rotation angle is established. Then, the excellent mother constellations (mother codebook) are reconstructed. The proposed mother codebook design method demonstrates excellent performance in terms of the bit error rate and is found to be superior to existing codebook methods. It can provide a universal mother codebook for user codebooks, thus yielding excellent codebooks for efficient SCMA applications and establishing a technical basis for efficient 5G and 6G applications.