Cost-Effective Migration towards C-RAN with Optimal Fronthaul Design

Centralized Radio Access Network (C-RAN) hasbeen recently proposed to increase network capacity, reduceenergy consumption, and improve scalability. However, C-RANrequires an extensive modification to the current infrastructure,which results in a considerable deployment cost. In this paper,we conduct a techno-economic study to evaluate the migrationcost of C-RAN, and we propose a methodology for cost andenergy efficient C-RAN deployment. We exploit the conceptof total cost of ownership, defined as the sum of capital andoperational expenditures. We formulate a Digital Unit (DU) poolplacement optimization problem as Mixed Integer Linear Programming(MILP), which minimizes the total cost of ownership.We compare the total cost of ownership of C-RAN to that ofthe existing infrastructure, under different deployment scenariossuch as greenfield and brownfield deployment of fiber and DUpool, and different cell sizes. The results show that the opticalinfrastructure plays a determinant role in the migration cost ofC-RAN. If greenfield fiber is assumed, the migration cost cannotbe compensated in a reasonable amount of time. If brownfieldfiber is assumed, the migration cost is considerably reduced, anda more feasible C-RAN deployment is achieved.QC 20170803