The number of mobile broadband subscribers is increasing along with mobile data traffic onrnthe Ethiopian mobile network. Mobile customers are facing dissatisfied service quality as thernnumber of subscribers is increasing due to resource sharing as well as increasing interference.rnTo improve service quality, network optimization and expansion work has been continuouslyrnperformed. In order to maximize network capacity and coverage, ethio telecom upgrading therncellular network by using Long Term Evolution Advanced (LTE-A), an indoor building solutionrnsystem, and adding base stations/transmitters. In such networks, Inter-Cell Interference (ICI)rnbecomes more challenging, which mainly affects network performance. So, to overcome thernaforementioned problem, operators are required to develop an effective approach that adoptsrndifferent interference mitigation techniques.rnThis thesis study presents a Coordinated MultiPoint (CoMP) transmission technique that canrnbe considered as an effective way to improve spectral efficiency and system throughput performance.rnThe thesis focused on downlink ICI mitigation in the LTE-A network within AddisrnAbaba. Comparative analyses and evaluations were performed for various CoMP and non-rnCoMP schemes. Taking into account performance metrics such as Signal to Interference plusrnNoise Ratio (SINR), spectral efficiency, and system throughput by performing radio propagationrnusing WinProp and system-level simulation using the static simulator Matlab.rnThe performance evaluation of the simulation study results obtained that the SINR gain improvesrn1.2dB and 1.4dB for the intra-site CoMP system, the Dynamic Point Blanking (DPB)rnCoMP system improves up to 3dB and 1.9dB, and the Joint Transmission (JT) CoMP systemrnimproves 3.7dB and 2.8dB for the cell edge and average users respectively. Spectral efficiencyrngain improved by 1.4bps/Hz, 2.4bps/Hz, and 3.2bps/Hz for intra-site CoMP, DPB CoMP, andrnJT CoMP scenarios, respectively. In addition, the throughput gain was achieved at 33% andrn15% for intra-site CoMP, 70%, and 45% for DPB CoMP, and 97% and 70% for JT CoMP forrnthe cell edge and average users, respectively. Therefore, the proposed interference mitigationrnsolutions have been proven to provide a significant performance improvement for the LTE-Arnnetwork and are worthy of deployment on the existing Addis Ababa LTE-A networks.