  In this paper, we study the cell planning problem for a two-tier cellular
network containing two types of base stations (BSs)-- i.e. with fiber backhaul,
referred to as wired BSs (W-BSs), and BSs with wireless backhaul, referred to
as unwired-BSs (U-BSs). In-band full-duplex wireless communications is used to
connect U-BSs and W-BSs. We propose an algorithm to determine the minimum
number of W-BSs and U-BSs to satisfy given cell and capacity coverage
constraints. Furthermore, we apply our proposed non-dominated sorting genetic
algorithm II (NSGA-II) to solve both cell planning and joint cell and backhaul
planning problem to minimize the cost of planning, while maximizing the
coverage simultaneously. Additionally, the considered cell planning program is
developed into an optimization by including the problem of minimizing the cost
of fiber backhaul deployment. In order to analyze the performance of the
proposed algorithm, we study three different deployment scenarios based on
different spatial distributions of users and coverage areas. The results show
the superiority of our proposed NSGA-II algorithm for both cell planning and
joint cell and backhaul planning to other well-known optimization algorithms.
The results also reveal that there is a trade-off between cell deployment costs
and SINR/rate coverage, and W-BSs are placed in congested areas to consume less
resources for wireless backhauls. Similarly, a trade-off between cell and fiber
deployment costs and SINR/rate coverage is observed in planning. We show that
for realistic scenarios desirable solutions can be selected from the Pareto
front of the introduced multi-objective problem based on given cellular
operator policies.
