This paper investigates the positioning of the pilot symbols, as well as the power distribution between the pilot and the communication symbols in the OTFS modulation scheme. We analyze the pilot placements that minimize the mean squared error (MSE) in estimating the channel taps. In addition, we optimize the average channel capacity by adjusting the power balance. We show that this leads to a significant increase in average capacity. The results provide valuable guidance for designing the OTFS parameters to achieve maximum capacity. Numerical simulations are performed to validate the findings.

翻译：本文研究了OTFS调制方案中导频符号的定位，以及导频与通信符号之间的功率分配问题。我们分析了能够最小化信道抽头估计均方误差（MSE）的导频放置方式。此外，通过调整功率平衡，我们优化了平均信道容量。研究表明，该方法可显著提升平均容量。所得结果为设计OTFS参数以实现最大容量提供了有价值的指导。数值仿真验证了研究结果。