Energy Efficiency of Relay Operation in Millimeter-Wave Mobile Broadband Systems

The growing mobile data demand has led to the investigation of millimeter-wave (mm-wave) band which makes the communication systems can achieve multi-gigabit data rate. Due to the high attenuation phenomenon of mm-wave, however, the mm-wave system contains the ``dead zones'' where users cannot receive mobile data. To cover dead zones, deployment of relay stations becomes an important issue for constructing mm-wave systems. In addition, according to growing interests on green communication, energy efficiency of the communication system becomes another important issue. In spite of that importance, there is no study about energy efficiency of relaying in the mm-wave system. In this paper, we model the mm-wave systems considering relay operation. And then, we analyze energy efficiency of relay operation compared to direct transmission of the systems. Finally, the numerical results show that the relay operation makes better energy efficiency than direct transmission in certain criteria.