基于四元素准正交设计的空时分组码

Space time block code based on quaternion quasi-orthogonal design

提出了一种基于四元素准正交设计的空时分组码,该种码满足准正交设计关系,可以通过极化天线进行满码率发射和接收.首先建立了信道模型,然后设计出发射天线数为4的四元素准正交空时分组码,采用快速最大似然译码算法进行译码,最后将其与天线数为4的传统准正交设计空时分组码分别进行了性能仿真.结果表明,所设计的四元素准正交设计空时分组码在不增加发射天线和接收天线的情况下,可以降低系统误码率,提高系统性能.分别采用BPSK,QPSK和8PSK,当SNR=10dB时,新码的误码率比准正交码分别降低0.5-1个数量级,而在SNR=15dB时,则分别降低约2个数量级.

A new kind of space time block code based on quatemion quasi-orthogonal design is introduced in this paper. The new code can be transmitted and received through dual-polarized antennas with full transmission rate. The channel model is formulated firstly, then this kind of space time block code for four transmit antennas is designed, and fast maximum likelihood sequence decoding method is adopted. Finally the new code is compared with the quasi-orthogonal space time block code for 4 transmit antennas. The simulation results show that the new code can decrease the bit error rate and improve the system performance with the same transmit and receive antennas. When SNR = 10 dB, the bit error rates of the new codes are decreased about 0. 5 to 1 order of magnitude compared with that of the old code for BPSK,QPSK and 8PSK, respectively. While SNR = 15 dB, the bit error rates of the new codes are decreased about 2 orders of magnitude.