Department of Electrical and Electronic Engineering, Yonsei University, Seoul 03722, Korea.
Samsung Electronics Company Ltd., Suwon 16677, Korea.
Sensors (Basel). 2021 May 7;21(9):3250. doi: 10.3390/s21093250.
Full-duplex (FD) is a promising technology for increasing the spectral efficiency of next-generation wireless communication systems. A major technical challenge in enabling FD in a real network is to remove the self-interference (SI) caused by simultaneous transmission and reception at the transceiver, and the SI cancellation performance depends significantly on the estimation accuracy of the SI channel. In this study, we proposed a novel partial SI channel training method for minimizing the residual SI power for FD massive multiple-input multiple-output (MIMO) systems. Based on an SI channel training framework under a limited training overhead, using the proposed scheme, the BS estimates only a part of the SI channel vectors, while skipping the channel training for the other remaining SI channel vectors by using their last estimates. With this partial training framework, the proposed scheme finds the optimal partial SI channel training strategy for pilot allocation to minimize the expected residual SI power, considering the time-varying Rician fading channel model for the SI channel. Therefore, the proposed scheme can improve the sum-rate performance compared with other simple partial training schemes for FD massive MIMO systems under a limited training overhead. Numerical results confirm the effectiveness of the proposed scheme for FD massive MIMO systems compared with the full training scheme, as well as other partial training schemes.
全双工（FD）是提高下一代无线通信系统频谱效率的一项有前途的技术。在实际网络中实现 FD 的主要技术挑战是消除收发器同时传输和接收引起的自干扰（SI），而 SI 消除性能在很大程度上取决于 SI 信道的估计精度。在这项研究中，我们提出了一种新的部分 SI 信道训练方法，用于最小化 FD 大规模多输入多输出（MIMO）系统的剩余 SI 功率。基于有限训练开销下的 SI 信道训练框架，在所提出的方案中，BS 仅估计部分 SI 信道向量，而通过使用其最后一次估计跳过其他剩余 SI 信道向量的信道训练。通过这种部分训练框架，所提出的方案找到了用于导频分配的最佳部分 SI 信道训练策略，以最小化考虑到 SI 信道的时变莱斯衰落信道模型的预期剩余 SI 功率。因此，与 FD 大规模 MIMO 系统中的其他简单部分训练方案相比，在所提出的方案可以在有限的训练开销下提高和率性能。数值结果证实了与全训练方案相比，所提出的方案在 FD 大规模 MIMO 系统中以及与其他部分训练方案相比的有效性。
