With the massive propagation of the mobile phone traffic and demand for high data rate transmission has grown this day, the current cellular spectrum for bands less than 3 GHz is severely deficient and cannot convoy these requirements, which requires the search for suitable solutions for the application of the fifth generation 5G. The potential of millimetre-wave (mm-wave) to provide a high data rate (Gigabits per second) has attracted great interest to become a broadband candidate for the fifth generation of cellular communications networks. To increase the spectral efficiency of cellular networks, Massive multi-input multi output (MMIMO) is considered one of the most promising methods, by equipping the base station with antenna arrays with hundreds or thousands of active elements with the use of beamforming technology and conducting coherent processing on both sides of the transmitter and receiver. In this paper, two mm-wave frequencies(28GHz and 73GHz) have been compared in terms of spectrum efficiency using a massive MIMO using two beamforming methods: conjugate beamforming (CB) and zero-forcing (ZF).

5G overcame the severe shortage of cellular spectrum used by its predecessors by using millimeter-wave (mmWave) packets that provide broadband to 5G wireless networks. The problem of Inter User Interference (IUI) is also one of the most important and dangerous problems facing telecommunication networks. IUI is exacerbated, especially in the areas near the Tower as the narrow coverage area compared to the areas farthest from the Tower. As a result of this effect, our paper proposes a new model by taking a matrix of antennas at different heights and coordinating mmWave beams. Coordinated Multi-Point (CoMP) is the essential solution in 5G to improve throughput and coverage performance. As a result, millimeter wave technology was used in the proposed CoMP system. The new proposed system works to study the effect of the height of the antenna matrix on reducing IUI by calculating the peak capacity value on the user with different distances. In addition to the impact of the azimuth angle of arrival AoA (∅) on capacity when implementing each scenario. Simulation results show that the proposed system scheme with different heights of the antenna matrix can get a large capacity than a traditional system. Choosing the best antenna matrix height reduces interference and improves capacity. The highest improvement obtained is 53%.

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Multi-hop ad-hoc networks with chain and cross topologies proved to be an excellent solution for low-cost of computer networks. It provides quick and easy networking in all environments. In this paper, a model of multi-hop ad-hoc network is suggested, in addition, a new model for multi-hop wireless ad-hoc network with chain and cross-topologies are designed using Simevents tools, it takes into account the effect of the contention process and losses on the MAC layer. Finally a cross-layering algorithm called TCP Contention Control (TCC) algorithm is applied to the proposed model using Simevents tools to improve the throughput performance. The results show that the improved throughput percentage of chain and cross-topologies are equal to 33.5% and 49% respectively.

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