双迭代级联译码的Turbo V-BLAST结构

Double-Iterated Concatenated Decoding for Turbo V-BLAST System

垂直贝尔实验室分层空时(V-BLAST)方案能有效提高系统的信道容量而成为研究的热点。但多发送天线造成了接收信号的空间干扰,这严重造成了误比特(误帧)系统性能的下降。在接收端,采用了迫零(Zero-forcing)排序的迭代混合干扰消除(HybirdInterferenceCancellation,HIC)算法,相比迫零排序的串行干扰消除(SerialInterferenceCancellation,SIC)算法,在降低复杂度的同时提高系统性能。干扰消除后的软信息经过Turbo迭代译码,得到的硬判决信息可以反馈回到V-BLAST的迭代ZF-HIC干扰检测,进行系统级联迭代。因此,文中的TurboV-BLAST结构具有双迭代级联的多迭代环特征。仿真证明能很大程度上改进系统的BER和FER,是一种理想的系统结构。

Vertical Bell Lab＇s Layered Space Time （V-BLAST） scheme improves greatly system channel capacity, however multi-transmit antennas introduce space interference, which degrades sharply BER （FER） performance. In order to overcome effectively the space interference, an iterative ordered Zero-Forcing Hybird Interference Cancellation （ZF-HIC） algorithm is adopted. Compared to conventional Zero-Forcing Serial Interference Cancellation （ZF-SIC） algortithm, ZF-HIC provides better BER and FER performance with a lower computational complexity. Soft-information after ZF-HIC detector is sent to Turbo iterative decoding and the resulting hard decision-information can be sent back to V-BLAST detector again to further update and improve the performance of ZF-HIC detector. So, the Turbo V-BLAST has the double-iterated concatenated decoding structure. The simulation results are presented to verify its advantages.