In the last few years, mostly in the urban areas, there is tremendous growth in the cellular traffic. Heterogeneity, high specification devices and increasing user density in the cellular networks have become major issues. Recent studies and researches are mainly relying on efficient modeling and analysis of such high demanding networks. This paper addresses the effect of deploying small cells (SCs) on an existing homogeneous and heterogeneously distributed macro cellular network. The effect on average user throughput for two scenarios are discussed - (i) when users are served by macro BS only and, (ii) when users are served by macro BS along with SCs deployed by applying k-means algorithm. For analysis of the distributions we consider the allocation of 1-resource block (RB) per user and 50-RB per user in the cell. A homogeneous Poisson Point Process (PPP) which generates entities in a uniform manner, is used for modeling the homogeneous distribution. The spatial heterogeneity is obtained by adopting Cox process ( also known as doubly stochastic poison process, DSPP) which allows uneven distribution of entities in space. The simulated results and plotted graphs depicts that, average user throughput gets increased gradually with deployment of 2, 4, 6, and 8-SCs in the macro cell.