准正交空时分组码可以对天线数大于2的复信号星座进行全速率的编码,但是准正交空时分组码采用成对最大似然译码(DML),其译码复杂性随信号星座数量呈指数增长。针对准正交空时分组码的这种缺点提出了一种快速最大似然译码(FML)算法。仿真及计算结果显示,在信号星座数较大时,采用快速最大似然译码方法可以在保证性能损失很小的前提下,使接收机的译码复杂性减少2~3个数量级,而且该方法可以推广到任意数量的发射天线。
Quasi-orthogonal space-time block codes can provide full rate of complex signal constellation when more than two antennas are used at transmitter. Quasi-orthogonal space-time block codes use double maximum likelihood (DML) decoding at receiver~ the decoding complexity increases exponentially. In order to overcome the disadvantage, therefore, a fast maximum likelihook decoding for quasi-orthogonal space-time block codes is proposed. Simulation and calculation results show that the fast detection algorithm can reduce the complexity about two or three quantity under the precondition that DML and the performance reduces slightly, when the signal constellation is large. This fast decoding algorithm may be employed in arbitrary transmitting antennas.