Research Of Energy Efficiency For D2D Communication Underlaying IMT-2020

In recent years, with the rapid development of mobile Internet and Internet of things, drastic increase in data traffic, an increasing number of devices accessing communication networks, the current cellular network needs to introduce new technologies to meet the needs of user experience. Device-to-Device(D2D) communication technology is an enhanced communication in cellular networks technology, which allows direct data communication within a certain distance of the two terminals, without a relay base station. D2 D communications can improve the spectrum efficiency, reducing the base load, reduce delays and Terminal transmit power, therefore, paid much attention.Introduction of D2 D disrupt communication in cellular networks, the need for interference management, common interference management include resource allocation and power control, in the previous study, throughput improvement is the goal of resource allocation and power control. For green communications considerations and the limitations of battery technology, the improvement in energy efficiency as this papers research goal, D2 D communications energy efficiency issues are studied.Content of this article is to study the problem of energy efficiency in resource allocation in two ways. In concentrated type resources distribution schema, consider a scene of single cell with more users, the energy efficiency expression of D2 D links reusing multiple cellular links is derived, introduced subchannel distribution variable to decide resources distribution for D2 D communications, with relaxation algorithm solution problem of D2 D links energy efficiency maximize, obtained best of subchannel distribution variable and transmission power, and by base station broadcast to all users in the cell. In the distributed resource allocation scheme, the problem of distributed resources allocation model as overlapping coalition formation game, through the coalition formation algorithm construction union, every user in a same union reuse the same spectrum resources. Power control for each Union is then modeled as non-cooperative game theory, proved the existence of Nash equilibrium, Nash equilibrium of power replacing the initial maximum transmitting power, to enhance the user’s energy efficiency.