  The explosive demands for high quality mobile video services have caused
heavy overload to the existing cellular networks. Although the small cell has
been proposed to alleviate such a problem, the network operators may not be
interested in deploying numerous base stations (BSs) due to expensive
infrastructure construction and maintenance. The unmanned aerial vehicles
(UAVs) can provide the low-cost and quick deployment, which can support
high-quality line-of-sight communications and have become promising mobile BSs.
In this paper, we propose a quality-of-experience (QoE)-driven UAV-enabled
pseudo-analog wireless video broadcast scheme, which provides mobile video
broadcast services for ground users (GUs). Due to limited energy available in
UAV, the aim of the proposed scheme is to maximize the minimum peak
signal-to-noise ratio (PSNR) of GUs' video reconstruction quality by jointly
optimizing the transmission power allocation strategy and the UAV trajectory.
Firstly, the reconstructed video quality at GUs is defined under the
constraints of the UAV's total energy and motion mechanism, and the proposed
scheme is formulated as a complex non-convex optimization problem. Then, the
optimization problem is simplified to obtain a tractable suboptimal solution
with the help of the block coordinate descent model and the successive convex
approximation model. Finally, the experimental results are presented to show
the effectiveness of the proposed scheme. Specifically, the proposed scheme can
achieve over 1.6dB PSNR gains in terms of GUs' minimum PSNR, compared with the
state-of-the-art schemes, e.g., DVB, SoftCast, and SharpCast.
