Interference Avoidance Techniques for Closed Access Small Cells Networks

This paper investigates the impact of small cells networks deployment in a typical residential environment. First we will present some aspects with regard to small cells coverage area when deployed in a macrocell sector area. Using the observations with regards to coverage we will further investigate the deployment of a residential femtocell network, implemented in closed access form. The paper proposes two algorithms in order to reduce the interference level at the macrocell user site, considering that the operator owns at least two carrier frequencies which will be used for both the macrocellular and femtocellular layers. The performances of the two proposed algorithms are presented in comparison with the case when no interference mitigation methods are implemented. The obtained results show a significant improvement in the signal to interference and noise ratio, obtained at the user location.