  System-centric modeling and analysis are of key significance in planning and
optimizing cellular networks. In this paper, we provide a mathematical analysis
of performance modeling for LTE networks. The system model characterizes the
coupling relation between the cell load factors, taking into account
non-uniform traffic demand and interference between the cells with arbitrary
network topology. Solving the model enables a network-wide performance
evaluation in resource consumption. We develop and prove both sufficient and
necessary conditions for the feasibility of the load-coupling system, and
provide results related to computational aspects for numerically approaching
the solution. The theoretical findings are accompanied with experimental
results to instructively illustrate the application in optimizing LTE network
configuration.
