Energy efficiency performance of WiFi/WiMedia relaying in hybrid ad-hoc networks

Current and future mobile terminals (MTs) possess multiple radio interfaces, which provide high data rates and ubiquitous connectivity. The mentioned advances come on the expense of higher energy consumption due to the multiple interfaces. Cognitive radios and cooperative communications have been widely used in wireless communications for better spectrum usage. In this paper, we use these two disruptive technologies for the sake of reducing energy consumption of MTs. Towards this end, we construct a context-aware framework for choosing the best relay paths for MTs to maximize their energy saving. In this framework, MTs willing to communicate with the access point exchange context information with their nearby MTs and form cooperative cluster whenever it reduces their energy consumption. We investigate the energy efficiency performance of a cooperative relaying in a hybrid ad-hoc network scenario with multi-standard MTs while exploiting idle MTs as relay stations. Simulation results show that MTs can reduce up to 50% of their energy consumption in a lossy environment with heavy shadowing and multipath fading impairments.