基于资源块星座图的稀疏码多址接入码本设计

SCMA codebook design based on resource block constellation

针对基于多维母星座图的典型稀疏码多址接入(SCMA, sparse code multiple access)码本设计方法存在设计复杂度高和资源块上星座点之间的最小欧氏距离难以确定的问题,提出了一种基于资源块星座图的SCMA码本设计方法。所提方法通过将多维母星座图的设计转化为二维资源块星座图的设计,降低了星座图的设计复杂度;从资源块星座图出发的码本设计方法能最大化资源块上星座点之间的最小欧氏距离,较之由多维母星座图得到用户码本的设计方法性能更好。仿真结果表明,基于资源块星座图的SCMA码本设计方法相较基于多维母星座图的典型码本设计方法,系统的误比特率(BER, bit error rate)性能有较显著的改善。

Aiming at the problems of typical sparse code multiple access codebook design scheme based on multidimensional mother constellation that the complexity is high and the minimum Euclidean distance between constellation points on resource blocks is difficult to determine,a SCMA codebook design scheme based on resource block constellation was proposed.By converting the design of multidimensional mother constellation into the design of two-dimensional resource block constellation,the design complexity of constellation was reduced.And the codebook design scheme starting from resource block constellation could maximize the minimum Euclidean distance between constellation points on resource blocks,which was better than the design method in which user codebooks were obtained from multi-dimensional mother constellation.Simulation results show that the proposed SCMA codebook design scheme based on resource block constellation can significantly improve the BER performance of system compared with the typical codebook design scheme based on multidimensional mother constellation.