Joint Relay Placement and Sub-carrier Allocation in Sustainable Wireless Networks

Abstract

Nowadays, the increasing concern on environmental protection has boosted the research of sustainable wireless networks construction. It is anticipated that wireless devices including BSs and RNs will be powered by green energy to sustain the operations of wireless networks. However, green energy is normally sustainable yet variable, which makes it challenging to exploit green energy sources in the deployment and management of a sustainable wireless network. In this chapter, the network planning and resource management issues are re-visited in the context of sustainable wireless networks based on statistical historic data. The objective is to deploy the minimal number of green RNs in the sustainable wireless networks, such that the harvested energy can fulfill the throughput requirement of users based on the cost threshold. To this end, we jointly consider the RN placement and sub-carrier allocation problem, and formulate it as a mixed integer non-linear programming (MINLP) problem. As the formulated problem is NP-complete, we propose two low-complexity heuristic algorithms, namely RNP-SA with top-down/bottom-up algorithms (RNP-SA-t/b) to solve it .