5 where ¯ K = P max C σ 2 , C is the path loss constant, r is the user distance from its serving BS, ψ and η denotes the shadowing and small scale fading coefficient between use r and BS on a given subcarrier, respectively, β is the path loss exponent, σ denotes the thermal noise at the receiver and ζ is the composite fading. Note that all users are assumed to be associated with their closest BS [6], [11], therefore r ≤ R . Each cell is divided into K concentric circular regions. Since path loss decays exponentially from cell center to cell edge, therefore, we consider discretization of cellular region in such a way that the path loss decay within each circular region remains constant or uniform. The main motivation for dividing the cell into a discrete set of circular regions relies on the fact that the channel statistics of the users located in a given circular region become relatively similar especially for large values of K . More explicitly, the characterization of the circular regions can be demonstrated as follows: where κ is the path loss decay within each circular region [dB]. Due to the exponential nature of the path loss, it varies rapidly near the cell center than at the cell edge, therefore, (i) each of the k th circular region bounded by two adjacent rings, i.e., r$_{k}$ and r$_{k}$$_{−}$$_{1}$ possess non-uniform width Δ$_{k}$ = r$_{k}$ − r$_{k}$$_{−}$$_{1}$ ; (ii) the number of circular regions are high in the cell center than at the cell edge; (iii) the average number of users located within k th circular region bounded by ring r$_{k}$ and r$_{k}$$_{−}$$_{1}$ are considered to be located at r$_{k}$ . Note that, this is an approximation which is required for deriving the analytically tractable model of ICI and in any case it is not required for the Monte-Carlo simulations. The average number of users in each ring k (for analysis) can then be given as: It is important to note that u$_{k}$ can be a fraction; therefore, we round off the fractional part of users. B. Main Steps of the Proposed Framework log$_{10}$ r$_{k}$ = κ + 10 β log$_{10}$ r$_{k}$$_{−}$$_{1}$ 10 β , r ≤ R (2) u$_{k}$ = U ( r 2 k − r 2 k − $_{1}$) R 2 k = 1 , 2 , · · · , K (3) In order to characterize the statistics of the uplink and downlink ICI for generalized fading channels and various scheduling schemes, the proposed framework mandates the following steps: i) Derive the distribution f$_{r}$$_{sel}$ ( r ) of the distance of the allocated user r$_{sel}$ in a given cell from its serving BS based on the deployed scheduling scheme. Without loss of generality, we assume the same scheduling scheme is implemented in all cells; therefore, f$_{r}$$_{sel}$ ( r ) remains the same for all cells.