基于免疫克隆算法的非均匀星座优化

针对在使用均匀调制星座时比特交织编码调制容量与香农容量差距较大的问题,提出使用免疫克隆算法进行非均匀星座优化。该算法分为两层迭代:外层迭代通过仿真误比特率性能得到当前星座的工作点(信噪比);内层迭代在外层迭代得到的工作点下通过克隆、变异、替换等操作得到新的星座。仿真结果表明,与均匀星座以及美国高级电视系统委员会发布的第三版地面数字电视标准中所采用的非均匀星座相比,该算法优化的星座可有效提升系统容量及误比特率性能。因此,提出的算法适合用于非均匀星座优化。

Non-Uniform Constellation Optimization Based on Immune Clone Algorithm

In order to reduce the gap between the BICM(bit interleaved coded modulation) capacity and the Shannon capacity when using uniform constellation,a novel immune clone algorithm is proposed for non-uniform constellation optimization in this paper.The algorithm consists of two layers of iteration.The outer iteration obtains the working point(signal-tonoise ratio) of the current constellation by simulating the bit error rate performance.The inner layer iteration obtains a new constellation by clone,mutation,and replacement under the working point obtained by the outer iteration.Simulation results show that,compared with the uniform constellation and the non-uniform constellation used in ATSC 3.0(Advanced Television Systems Committee),the constellation optimized by the proposed algorithm can provide higher BICM capacity and better bit error rate performance.Thus,the proposed algorithm is suitable for non-uniform constellation optimization.