Yihenew, WondieBeza, Mengistu2022-02-142023-11-042022-02-142023-11-042021-12http://etd.aau.edu.et/handle/123456789/30032The increase in smart device numbers and also high-capacity demanding services has led to growth in wireless cellular data traffic. This forces mobile operators to increase network capacity to meet subscriber demand. In order to increase network capacity, one solution can be dense network with macro cell, however this has high deployment cost as well as running cost. Therefore, Heterogeneous cellular networks (HetNets) can be a solution to serve this high demand on mobile data traffic and minimize cost. HetNets consist of low power cells (micro / pico / femto cells) installed on the tier of well-planned macro base station (BSs). Due to random deployment of small BSs, the interference level in the network increases, especially in cell-edge areas, where two or more BSs compete for coverage and can transmit and receive from the same user equipment (UE) device. Interference is big challenge to capacity improvement and coverage enhancement, as well as for spectral efficiency and energy efficiency. To improve interference problem, operator need to deploy interference management techniques proposed in third Generation Partnership Project(3GPP), such as Inter Cell interference coordination eICIC, Further Inter Cell interference coordination (FeICIC), and Coordinated Multipoint (CoMP). This thesis mainly focuses on downlink inter-cell interference in LTE- A macro-pico scenario and uses eICIC to mitigate intercell interference in Addis Ababa, Bole area. Due to small coverage area of pico cell, cell range expansion has been introduced to encourage UEs offloading from macro cell to pico cell and also Almost Blank Subframes (ABS) to mute macro cell and reserve resource for pico cell users. Computer simulations are carried out using matlab code after carrying out network simulation in winprop. According to the observation, Pico cell users are experiencing interference from high-power macro nodes. Cell edge users are experiencing high interference from macro cell and their throughput is low without eICIC. Moreover, the simulation results demonstrate HetNet deployment improves overall system throughput but interference is an issue to be solved. The simulation result shows 70% increase in cell edge user performance by using eICIC.en-USHeterogeneous networkeICICcell range expansionalmost blank subframesThesis