旋转星座下极化准正交空时分组码及性能分析

Quasi-orthogonal polarization space time block codes with signal constellations rotation and performance analysis

设计了发射天线数分别为8和6、码率为3/4的极化准正交空时分组码,对星座图进行最佳角度旋转,接收机采用成对译码算法,并对未旋转—极化、旋转—极化、未旋转—传统、旋转—传统这4种准正交空时分组码进行了仿真比较。结果表明,在相同条件下,当采用双极化天线时,星座图旋转对系统误码率性能改善不明显;当采用单极化天线时,旋转对系统误码率性能改善明显。

A new kind of rate 3/4 space time block code based on quaternion quasi-orthogonal and the quasi-orthogonal polarization space time block code with signal optimal constellation rotation for eight and six transmit antennas were de- signed. The pair-wise decoding algorithm was adopted at the receiver. The simulation and comparison among polarization quasi-orthogonal, rotational polarization quasi-orthogonal, quasi-orthogonal and rotational quasi-orthogonal were given respectively. The results show that there is only a little improvement by signal constellations rotation when the dual-polarized antennas are used and there is a great improvement by signal constellations rotation when the sin- gle-polarized antennas are used for bit error rate performance at same conditions.