基于互满正交设计的差分空时分组码

Differential Space-Time Block Code Based on Amicable Orthogonal Design

本文针对多天线系统提出了基于互满正交设计的差分空时分组码(Amicable-orthogonal-design-based Dif-ferential Space-Time Block Code,ADSTBC).与已有的差分空时调制方法相比,ADSTBC对信号星图无任何限制,因而可采用高效的调制技术(如QAM、APSK等)提高频谱效率.基于平坦Rayleigh衰落信道,给出了具有线性复杂度的最大似然差分译码器(Maximum-Likelihood Differential Decoder,MLDD).若在ADSTBC中采用QAM星图,MLDD可进一步简化成独立地检测每一数据符号的实部和虚部,降低了实现代价;并且,随着QAM星图阶数的增加,MLDD用于检测单个数据符号的计算量将保持不变.

We present an amicable-orthogonal-design-based differential space-time block code (ADSTBC) for multiple antennas. Compared with the existing differential space-time modulation designs, our scheme imposes no restrictions on underlying signal constellation, and therefore can improve the spectral efficiency by exploiting efficient modulation techniques such as QAM, APSK etc. We then derive a maximum-likelihood differential decoder (MLDD) with linear complexity for flat Rayleigh fading channels. Particularly, when the QAM constellation is used in ADSTBC, MLDD can be further simplified to independently detect the real and imaginary parts of each data symbol, and accordingly the implementation cost can be greatly reduced. Moreover, the computational amount for detecting single data symbol is kept constant in MLDD while the order of the QAM constellation increases.