Wang Congcong, Feng Chunyan, Yang Yang, Guo Caili, Jia Bowen
Opt Express. 2022 Dec 19;30(26):45988-46000. doi: 10.1364/OE.470468.
Ordered successive interference cancellation (OSIC) detection has been investigated to mitigate the high spatial correlation for multiple-input multiple-output (MIMO) visible light communication (VLC) systems. However, existing OSIC schemes have to perform reordering and matrix inversion for each detected symbol, which may lead to high complexity when a large number of symbols are transmitted. In this work, a joint design of ordered QR decomposition precoding and SIC detection (OQR-SIC) is proposed for MIMO VLC systems. This work jointly investigates OQR precoding and SIC detection to reduce the detection complexity while alleviating spatial correlation issue for MIMO VLC systems. In OQR-SIC, with the upper triangular matrix obtained by QR decomposition, the SIC detector can detect the symbol sequentially without reordering and matrix inversion calculations. To improve the system data rate, we further optimize the ordering of the columns of the channel matrix before QR decomposition and the power allocation of transmitted signals under the constraints of dimming control, total electrical power and reliable SIC detection. Simulation results demonstrate that the proposed OQR-SIC achieves 2 dB and 9.8 dB signal-to-noise ratio gains compared to conventional QR-SIC in 4 × 4 and 9 × 9 MIMO VLC systems, respectively, when the bit error rate is 10.
为了减轻多输入多输出（MIMO）可见光通信（VLC）系统中的高空间相关性，人们对有序连续干扰消除（OSIC）检测进行了研究。然而，现有的OSIC方案必须对每个检测到的符号进行重新排序和矩阵求逆，当传输大量符号时，这可能会导致高复杂度。在这项工作中，针对MIMO VLC系统提出了一种有序QR分解预编码和连续干扰消除检测（OQR-SIC）的联合设计。这项工作联合研究了OQR预编码和连续干扰消除检测，以降低检测复杂度，同时缓解MIMO VLC系统的空间相关性问题。在OQR-SIC中，利用通过QR分解得到的上三角矩阵，连续干扰消除检测器可以顺序检测符号，而无需重新排序和矩阵求逆计算。为了提高系统数据速率，我们在调光控制、总电功率和可靠的连续干扰消除检测的约束下，进一步优化了QR分解之前信道矩阵列的排序和发射信号的功率分配。仿真结果表明，当误码率为10时，在4×4和9×9 MIMO VLC系统中，与传统的QR-SIC相比，所提出的OQR-SIC分别实现了2 dB和9.8 dB的信噪比增益。
