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Wireless mobile communication system has become an attractive technology and continues to evolve due to increasing demand for high data speed performance. In order to achieve high rate of data and to meet growing demand in mobile communication, large scale multiple antennas system involving the use of hundreds of antenna at the base station is regarded as a promising technology for next generation of wireless communication standard such as fifth generation (5G). However, due to multipath effect in wireless channel, the problem of severe attenuation in transmitted signal arises, which makes it very difficult for the receiver at base station (BS) to determine the optimum transmitted signal and thereby causing system performance metrics such as capacity to degrade. This paper presents maximizing receive capacity in large scale multiple input multiple out (or massive-MIMO) system based on maximal ratio combining (MRC) beamforming. The system is designed to mitigate multipath fading effect to improve system performance. The mathematic model of massive multiple antennas system channel was derived and maximum ratio combining technique was formulated. The entire system was modeled in MATLAB. Simulation results obtaining considering wireless communication over Rayleigh fading with varying number of base station antennas (M) using MRC indicated that system capacity for M = 128, 150, 200, 256, and 512 resulted in capacity of 29.53 bit/s/Hz, 30.36 bit/s/Hz, 31.85 bit/s/Hz, 33.12 bit/s/Hz, and 36.64 bit/s/Hz. Further simulations were conducted to compare the performance of MRC with selective combining (SC) and equal gain combining (EGC). The results of the comparison indicated that MRC outperformed SC and EGC. Therefore, the results of the developed system studied using typical parameters of 5G and implementing MRC to achieve improved performance in terms of capacity show it potential. |
