Weight based channel selection towards 5G in the unlicensed spectrum

The growth of the wireless and mobile communication data traffic has brought severe challenges to the present telecommunication systems. To meet the ever-increasing mobile traffic demand in the next 5th generation (5G) communication systems, deploying 5G in the unlicensed spectrum (5G-U), has been regarded as a promising technology. The Third Generation Partnership Project (3GPP) has specified the standardization of the Licensed Assisted Access (LAA) and its extension enhanced LAA (eLAA), to opportunistically transmit in the unlicensed spectrum. The LAA/eLAA systems share unlicensed spectrum resource with other networks, e.g., the Wi-Fi systems. In this article, we analyze the coexistence between the eLAA and the Wi-Fi systems in the unlicensed spectrum. We firstly establish the system model where the eLAA coexists with the Wi-Fi systems. Then, we theoretically derive and figure out the unfairness in the multi-channel occupancy rate between the eLAA and the Wi-Fi systems. After that, we propose a weight based channel selection method to improve the fairness of the coexistence. The numerical results demonstrate that by avoiding contentions and declining collisions, our method not only enhances the fairness, but also improves the overall unlicensed spectrum usage rate.