Abstract
Telecom companies in the different generations resorted to different tools to conquer connectivity issues like coverage, throughput and quality of service. The success is driving new services of diversified requirements and more traffic which dictates a continuous increase in data rates and improved performance. This work reviews the different technology tools used to meet rates and traffic requirements of the past and the present with a look into their role in future networks. The coming fifth generation (5G), in particular, is confronted by a number of antonym challenges of capacity, spectrum, energy, connectivity, performance, complexity, and cost. Suggested tools proposed to meet these challenges and the way they act to do so are reviewed and compared to current and past solutions. The tools discussed are the use of millimetric waves, massive multiple input multiple output antenna systems, indoor-outdoor separation, ultra-dense cooperative networks, and the increased reliance on users' terminals. The major constructional differences and tools differences between current and future 5G are finally emphasized.