3D MIMO在无线携能通信系统中的应用和优化设计

为了提高无线携能通信(SWIPT)的效率，在基站采用3维(3D)定向天线，通过动态调整天线下倾角，来开发垂直维度，从而增强SWIPT中能量和信息的传输效率。该文研究单小区多输入多输出(MIMO)SWIPT系统，基站和用户分别使用迫零(ZF)预编码和功率划分(PS)技术。构建以最小化发送功率为目标的优化问题，在信噪比(SNR)和获取功率的约束下，联合优化了天线下倾角，PS比和分配的功率。最佳PS比和最优功率分配以闭合表达式给出。仿真表明，所得到的优化解的性能优于具有可调下倾角的常规MIMO系统和不考虑垂直维度的2维(2D)方案。

Application and Optimal Design of 3D MIMO for Simultaneous Wireless Information and Power Transfer

In order to improve the Simultaneous Wireless Information and Power Transfer (SWIPT) efficiency, the Base Station (BS) employs the Three-Dimensional (3D) directional antennas and exploits the vertical domain by dynamically adjusting the antenna tilt. So the efficiency of energy and information transfer can be increased. The single-cell Multiple-Input Multiple-Output (MIMO) SWIPT system is studied where the BS applies Zero-Forcing (ZF) precoding and users use the Power Splitting (PS) technique. The optimization problem is formulated to minimize the transmit power subject to SNR and harvested power targets. And the antenna tilt, PS ratios and the allocated power of each user are jointly optimized. The optimal PS ratios and the optimal power allocation are given in closed-form expressions. Simulations show that the proposal outperforms conventional MIMO systems with an adjustable tilt and the Two-Dimensional (2D) scheme without considering the vertical domain.