Addressing the Quality-of-Service (QoS) requirements of users is crucial for
service providers to improve the network performance. Furthermore, the
transformation from the network-centric to user-centric service paradigm
requires service providers to focus on improving the Quality-of-Experience
(QoE) which is expected to become an important objective in Next Generation
Cellular Networks (NGCNs). Managing QoE is not only a technical issue but also
a marketing ability to improve profitability. An efficient strategy to improve
the profitability is to apply price differentiation for different service
levels. Unmanned Aerial Vehicle Base Stations (UAV-BSs) are envisioned to be an
integral component of NGCNs and they create opportunities to enhance the
capacity of the network by dynamically moving the supply towards the demand
while facilitating services that cannot be provided via other means
efficiently. However, building a reliable wireless backhaul link via optimized
resource allocation is a key issue for the placement of UAV-BSs. In this paper,
we consider a UAV-BS and a terrestrial network of Macro-cell Base Stations
(MBSs) that the UAV-BS rely on for backhauling. The problem is to determine the
3D location of the UAV-BS and the bandwidth allocations to each user to
maximize the profitability of service provided in terms of achievable data rate
levels. We develop a Mixed Integer Non-Linear Programming (MINLP) formulation
of the problem. To overcome the high complexity, we propose a novel search
algorithm that is very efficient in terms of solution quality and time. The
analysis performed through numerical evaluations reveal that offering multiple
data rate options to users improves the QoE and at the same time allows the
service providers to increase the total profit.