A review of techniques to avoid cross-Tier and co-Tier interference in femtocell networks

Femtocell networks are the proposed solution for deployment in homes that enables an indoor mobile user to achieve high speed downloading from the internet and make good quality voice calls. a femtocell network also provides relief to an overloaded macrocell network by servicing mobile users at home,those without the femtocell network have to be served by the macrocell. however,like all wireless networks,femtocell networks suffer from the problem of interference. this interference can be divided into two types,cross-tier (between femtocells and macrocells) and co-tier (between femtocells). the avoidance or management of these two types of interference is crucial to the proper functionality of a femtocell,i.e. to provide high data rate and high quality voice calls to indoor mobile users. several techniques have been proposed in literature to avoid these types of interference. these are cognitive radio,resource allocation,power control,q-learning and access control. the findings in the review indicate that,interference avoidance techniques such as cognitive radio,power control and q-learning outperforms the resource allocation and access control interference avoidance techniques in terms of high efficiency and low/moderate complexity.