Cost-minimized design for TWDM-PONbased 5G mobile backhaul networks

Dense deployment of small cells would be required to provide for high capacity and universal access to future fifth-generation (5G) mobile networks. However, this would require cost-effective and reliable backhaul connectivity between these small cells. Time and wavelength division multiplexed passive optical networks (TWDM-PONs) are considered a promising choice for this purpose. In this paper,we consider the cost-minimized design of a backhaul network for a 5G mobile system using TWDM-PON. For this, equipment and deployment costs are considered, and the design is based on satisfying network constraints such as the maximum number of subscribers per optical line terminal and themaximumnumber of subscribers per wavelength. Considering the fact that many small cell base stations are dispersed over an extensive wireless coverage, a K-means clustering-based algorithm is proposed for the optimal solution. The strategies of using multistage remote nodes and cable conduit sharing are applied to further reduce the labor cost of trenching and laying fibers. Our simulation results show that the proposed approaches can substantially reduce the backhauling cost in comparison with the traditional intuitive random-cut sectoring approach.