3 optimal solution. Motivated by the above discussed facts, we consider the problem of optimized resource allocation in the uplink of multi-cell OFDMA networks. Firstly, we compute an upper bound (UB) and lower bound (LB) to the optimal average network throughput. Also, we study the effect of ICI on the performance of the near-optimal single cell resource allocation scheme proposed in [2] which leads to another simple lower bound. Simulation results show that this lower bound is slightly loose but can be computed easily. Since the computation of the optimal solution is exhaustive, we then propose a centralized sub-optimal resource allocation scheme which uses a geometric programming (GP) based power control phase in conjunction with a heuristic subcarrier allocation phase. The proposed scheme possesses an iterative and computationally intensive subcarrier allocation phase. However, it can serve as an effective benchmark for the less complex schemes even without the power control phase. Furthermore, the power control phase is discussed in this paper for both high and general signal to interference plus noise ratio (SINR) regimes. Finally, we propose and evaluate less complex centralized and distributed schemes that are suitable for practical implementation. The rest of the paper is organized as follows: In Section II, the system model is defined and problem is formulated. In Section III, the bounds are derived and their complexity is analyzed. In Section IV and Section V, the proposed centralized and distributed schemes are explained. Section VI presents numerical results followed by concluding remarks in Section VII. Notation : Throughout the paper, we denote the sets of real and complex vectors of N elements by R N and C $^{N}$, respectively. Matrices are represented using boldface upper case letters while bold face lower case letters are used for vectors. N (0 , σ $^{2}$) represents a zero mean Gaussian random variable with variance σ $^{2}$. A network of L cells with a set of K users in each cell l is considered. Full reuse of the spectrum is assumed in all the cells (i.e., frequency reuse =1). Each base station (BS) is assumed to have N orthogonal subcarriers, and each subcarrier can be allocated to a single user per cell. II. SYSTEM MODEL AND PROBLEM FORMULATION DRAFT March 19, 2018