Full-duplex (FD)-enabled relay networks represent a relevant solution to two critical needs of next-generation networks, namely, radio coverage extension and high spectral efficiency of wireless communications. Under practical conditions, however, the FD mode may not be the best operational setting for the relay; rather, operating in half-duplex may be more convenient when harsh channel conditions add up to self-interference. One of the fundamental challenges in the design of FD relay networks is thus how to determine the relay operational mode and the value of transmit power at both the relay and the data source, so that the achievable data rate is maximized as time varies. We address this problem in a two-hop, MIMO network, accounting for practical operational conditions in which the source is unaware of the symbols that the relay is transmitting. In light of the problem complexity, we also derive a lower-bound to the maximum achievable rate, which proves to be tight, especially for low-medium SNR values. We then tackle massive MIMO networks, and exploit our asymptotic analysis in the number of antennas to derive a low-complexity, yet highly efficient, operational mode and transmit power allocation scheme for a finite-size scenario.

中文翻译：

---

中继状态有限的MIMO全双工网络

支持全双工（FD）的中继网络代表了下一代网络的两个关键需求的相关解决方案，即无线电覆盖范围扩展和无线通信的高频谱效率。但是，在实际条件下，FD模式可能不是继电器的最佳操作设置；它可能是继电器的最佳设置。相反，当恶劣的信道条件加起来会产生自干扰时，以半双工方式操作可能会更方便。因此，FD中继网络设计的基本挑战之一是如何确定中继器的工作模式以及中继器和数据源上的发射功率值，以使随着时间的变化可实现的数据速率最大化。我们在两跳MIMO网络中解决了这个问题，考虑到实际操作条件，其中信号源不知道继电器正在传输的符号。考虑到问题的复杂性，我们还推导了一个可达到的最大速率的下限，这被证明是严格的，特别是对于中低SNR值。然后，我们处理大规模的MIMO网络，并在天线数量上进行渐近分析，以得出低复杂度但高效的操作模式，并针对有限大小的情况分配发射功率。