Cell-free (CF) massive multiple-input-multiple-output (mMIMO) deployments are usually investigated with half-duplex (HD) nodes and high-capacity fronthaul links. To leverage the possible gains in throughput and energy efficiency (EE) of full-duplex (FD) communications, we consider a FD CF mMIMO system with practical limited-capacity fronthaul links. We derive closed-form spectral efficiency (SE) lower bounds for this system with maximum-ratio transmission/maximum-ratio combining (MRT/MRC) processing and optimal uniform quantization. We then optimize the weighted sum EE (WSEE) via downlink and uplink power control by using a two-layered approach: the first layer formulates the optimization as a generalized convex program (GCP), while the second layer solves the optimization decentrally using alternating direction method of multipliers. We analytically show that the proposed two-layered formulation yields a Karush-Kuhn-Tucker point of the original WSEE optimization. We numerically show the influence of weights on the individual EE of the users, which demonstrates the utility of WSEE metric to incorporate heterogeneous EE requirements of users. We also show that with low fronthaul capacity, the system requires a higher number of fronthaul quantization bits to achieve high SE and WSEE. For high fronthaul capacity, higher number of bits, however, achieves high SE and a reduced WSEE.

翻译：无细胞(CF)大规模多投入-多输出(MMIMO)部署通常以半双倍(HD)节点和高容量前导线连接方式进行调查。为了利用全倍(FD)通信的吞吐量和能源效率(EE)的可能收益,我们认为FD CF MMIMO系统具有实际有限能力前导线连接,我们从这个系统获得的封闭式光谱效率(SE)较低界限,有最高纬度传输/最大纬度混合(MRT/MRC)处理和最佳统一化。然后,我们通过下链接和上传电源控制优化加权和EEEEE(WEE)(EESE)(E)(E)(EE)(EE)(E)(E)(E)(E)(E)(E)(EE)(E)(EE)(E)(EE)(E)(E)(E(EE)(E)(E)(E)(E)(E) (P) (P) (M) (M) (M) (M) (M) (M(M) (M) (M(M) (M) (M) (M) (M(M) (M) (M) (M) (M) (M) (M(M) (M(M(M) (M) (M) (M) (M) (M) (M) (M) (M) (M) (M) (M) (M) (M) (M) (M) (M) (M) (M) (M(M(M) (M) (M) (M) (M) (M) (M) (M) (M) (M) (M) (M) (M) (M) (M) (M) (M) (M) (M) (M) (M) (M) (M(M(M) (M) (M) (M(M) (M) (M) (M) (M) (M) (M) (M) (M) (M) (M) (M) (M) (M) (M) (M) (M) (M) (M) (M) (M) (M) (