Faster-than-Nyquist (FTN) signaling is a non-orthogonal transmission technique offering a promising solution for future generations of communications. This paper studies the capacity of FTN signaling in multiple-input multiple-output (MIMO) channels for high acceleration factors. In our previous study [1], we found the capacity for MIMO FTN channels if the acceleration factor is larger than a certain threshold, which depends on the bandwidth of the pulse shape used. In this paper, we extend the capacity analysis to acceleration factors smaller than this mentioned threshold. In addition to capacity, we conduct peak-to-average power ratio (PAPR) analysis and simulation for MIMO FTN for varying acceleration factors for both Gaussian and QPSK symbol sets. Our analysis reveals important insights about transmission power and received signal-to-noise ratio (SNR) variation in FTN. As the acceleration factor approaches 0, if the transmission power is fixed, the received SNR diminishes, or if the received SNR is fixed, PAPR at the transmitter explodes.

翻译：超奈奎斯特（FTN）信号传输是一种非正交传输技术，为未来几代通信系统提供了一种前景广阔的解决方案。本文研究了高加速因子条件下多输入多输出（MIMO）信道中FTN信号传输的容量。在我们先前的研究[1]中，我们得到了当加速因子大于某一特定阈值（该阈值取决于所用脉冲波形的带宽）时MIMO FTN信道的容量。在本文中，我们将容量分析扩展至小于上述阈值的加速因子。除容量外，我们还针对高斯和QPSK符号集，对不同加速因子下的MIMO FTN系统进行了峰均功率比（PAPR）分析与仿真。我们的分析揭示了关于FTN系统中传输功率与接收信噪比（SNR）变化的重要见解。当加速因子趋近于0时，若传输功率固定，则接收信噪比下降；若接收信噪比固定，则发射机的峰均功率比急剧增大。