摘要
在广播和通信领域最新概念中,星座旋转作为一种分集技术被应用于DVB-T2标准。对于旋转星座采用基于硬判决的二维迭代LLR解映射算法进行了一些简化,但由于硬判决带来了误码传播,并且首次软信息计算仍较为复杂。提出了两种改进方案,分别从误码性能和运算复杂度方面对原算法进行了改进。仿真结果表明,信道条件较为恶劣时,改进方法在性能上优于原系统。
Constellation rotation as a diversity technology of new concept in the field of broadcast and communication is used in DVB-T2 standard. The two-dimension iterative LI~ solution for rotated QAM constellation based on hard decision simplified calculation, but due to the hard decision to bring the error propagation, and the judgment for the first time operation is more complex. Two improved schemes are presented in this paper, respectively im- proing from the aspects of BER performance and computation complexity. The simulation results show that under bad channel conditions, improving methods on the performance is better than that of the original system.
出处
《电视技术》
北大核心
2014年第7期130-132,213,共4页
Video Engineering
关键词
旋转星座
解映射
软信息
constellation rotation
demapping
soft information
