An analysis of wireless backhaul for picocell base stations in heterogeneous networks

In a wireless heterogeneous network (HetNet), picocell base stations are deployed by the operators to enhance the network capacity and coverage area. From the perspective of the operators, deployment of the picocell base stations needs to consider minimizing the backhaul cost without degrading the service to users. Multiple picocell base stations can be deployed in areas where signal from the macro base stations does not reach well and backhaul (such as wired or microwave link) links can be established between the picocell base station and the macrocell base station. In case wireless links between picocell base stations are to be established, a careful design is required for both channel allocation and placement of the pico cell base stations. In this paper, we develop a mathematical model to analyze the placement of the picocell base stations so that the minimum data rate requirement is guaranteed in the worst-case scenario of interference in the wireless links between the picocell base stations. The model is validated through simulations considering both fading and non-fading channel conditions.