  In this paper, we investigate network-assisted full-duplex (NAFD) cell-free
millimeter-wave (mmWave) massive multiple-input multiple-output (MIMO) systems
with digital-to-analog converter (DAC) quantization and fronthaul compression.
We propose to maximize the weighted uplink and downlink sum rate by jointly
optimizing the power allocation of both the transmitting remote antenna units
(T-RAUs) and uplink users and the variances of the downlink and uplink
fronthaul compression noises. To deal with this challenging problem, we further
apply a successive convex approximation (SCA) method to handle the non-convex
bidirectional limited-capacity fronthaul constraints. The simulation results
verify the convergence of the proposed SCA-based algorithm and analyze the
impact of fronthaul capacity and DAC quantization on the spectral efficiency of
the NAFD cell-free mmWave massive MIMO systems. Moreover, some insightful
conclusions are obtained through the comparisons of spectral efficiency, which
shows that NAFD achieves better performance gains than co-time co-frequency
full-duplex cloud radio access network (CCFD C-RAN) in the cases of practical
limited-resolution DACs. Specifically, their performance gaps with 8-bit DAC
quantization are larger than that with 1-bit DAC quantization, which attains a
5.5-fold improvement.
