Pareto optimization for Radio-over-Fiber 4G base stations backhauling

In the context of radio cells densification, Radio-over-Fiber (RoF)-based mobile backhauling is considered as a promising solution for cost-effective and flexible Radio Access Units (RAUs) backhauling. In this paper, we recall the main characteristics of an innovative optical network architecture called GeRoFAN (Generic RoF Access Network) aiming to federate 4G radio cells. However, transporting multiple radio frequencies (RFs) over an analog RoF link is subject to crosstalk and intermodulation distortions that may decrease the wireless system capacity. Supported by an analytical modeling of the relevant optical layer limitations, we propose an impairment-aware radio cellular backhauling scheme for GeRoFAN able to maximize the radio cellular capacity while achieving an efficient use of optical resources. This optimization problem is solved through a multi-objective genetic algorithm exploiting the concept of Pareto front. For a given static traffic load, compared to other placement strategies (best fit, first fit and random fit), our algorithm achieves an excellent compromise between the rejection ratio of the wireless system and the number of required optical channels.