为解决Turbo-OVCDM译码复杂度随码率指数增长的问题,提出了一种新的、通用的Turbo-OVCDM编译码方案.该方案包括1)在发送端由2个或多个Turbo-OVCDM低速率码的码字通过直接的叠加编码生成高速率码的码字;2)在接收端通过串行干扰抵消进行译码.与传统的由单个编码矩阵直接构造重叠码分复用方法相比,新方案的译码复杂度大大降低.性能仿真证实了新方案的可行性.
The decoding complexity of traditional type of Turbo-overlapped code division multiplexing( OVCDM) increases exponentially with the code rate. To solve this problem,a new Turbo-OVCDM coding and decoding approach was proposed. The maximum sum-rate achieving strategy in Gaussian multiple access channels was used to construct point-to-point coding scheme. Superposition of two or more TurboOVCDM codes and serial interference cancellation were applied for coding and decoding respectively.Numerical results demonstrate the feasibility of the proposed approach.