Conclusions and Future Directions

Abstract

In this brief, we aim at maximizing the network sustainability of wireless communication networks with green energy. The main content of this brief is shown as follows:

• We have investigated the green techniques and previous works related to sustainable wireless networks. Several research issues have been discussed including network planning, energy modeling and resource allocation. Moreover, the motivations and challenges related to these research issues have been highlighted.

• We have addressed the relay node placement and sub-carrier allocation (RNP-SA) issues, which have been jointly formulated into a mixed integer non-linear programming problem. Two low-complexity heuristic algorithms, namely RNP-SA with top-down/bottom-up algorithms (RNP-SA-t/b), have been presented to solve the RNP-SA problem . We have analyzed the time complexity of proposed algorithms, and our algorithms have shown good performance by numerical and simulation results.

• We have analyzed the characteristics of green energy by developing a generic analytical model. The closed-form solutions for the energy depletion probability and energy depletion duration have been derived. Based on the analysis, an adaptive resource management framework for relay path selection and admission control has been proposed. Extensive simulation results demonstrate that the network sustainability can be improved by mitigating the energy depletion probability and ensuring a large energy depletion duration of mesh APs.