【摘要】 通过引入多电平振幅调制和变换矩阵方法,提出了一种基于多幅值调制的差分正交空时分组码方案。该方案可克服通常基于PSK调制的单幅值差分空时码(DSTC,differential space-time coding)在高频带利用率下由于星座符号间的最小距离减小所带来的性能下降,而且可用于编码矩阵是非方阵情况,避免了已有方案仅适合于方阵码矩阵。与已有单幅值DSTC相比,所提方案有着高的频谱效率和编码增益,且可实现线性译码复杂度和高的码率。此外,还给出了所提方案级联信道编码时的性能。仿真结果表明所提方案与已有单幅值DSTC方案相比,有着较低的误比特率,而且信道编码后的所提多幅值DSTC也好于相应的单幅值DSTC。更多还原

【Abstract】 By introducing multiple levels quadrature amplitude modulation and matrix transform method,a multiple am-plitudes differential space-time coding(DSTC) scheme was developed.The scheme can avoid the performance loss of conventional DSTC schemes based on PSK modulation in high spectrum efficiency,and it can be applied to non-square code matrix.Compared with conventional PSK based single amplitude DSTC schemes,the developed scheme has higher spectrum efficiency by carrying information not only on phases but also on amplitudes.Moreover,it has linear decoding complexity,and higher code rate.Also,the performance of our DSTC scheme concatenated with channel codes was given.The simulations results show that our scheme has lower BER when compared with single amplitude DSTC schemes.And multiple amplitudes DSTC concatenated with channel coding also outperform corresponding single amplitude DSTC.更多还原