To handover or not to handover (as a secondary user): An energy efficiency perspective

Nowadays, most of the geographical areas are covered by multiple heterogeneous networks. Moving terminals within these areas usually switch from a network to another for different motivations, such as enhancing quality of service, improving throughput, reducing monetary cost, etc. Terminal switching, aka handover, may occur to a spectrum band where the terminal is unlicensed as implied in the cognitive radio concept. In such scenario, the terminal is served as a secondary user with a lower priority than licensed users. Moreover, such handover requires to obtain the necessary spectrum data by the terminal itself, which induces extra resources expenditure at the terminal-end, including time and energy. Thus, the decision to handover as a secondary user should be made by taking into account the available energy resources, especially, in view of the limited energy at the terminal end. In this article, we investigate this case from energy efficiency viewpoint, where we discuss all the involved factors that influence such handover decision.