Adaptive geolocation based interference control for hierarchical cellular network with femtocells

This paper presents an adaptive interference control method to mitigate undesirable interference from femtocells to macrocell users in hierarchical cellular networks. Such mechanisms usually require over-the-air signalling for estimation of interference resulting significant bandwidth overhead. The proposed ‘Adaptive Interference Scaling’ (AIS) method uses geolocation information for femtocell power control for interference avoidance. In this approach, each femtocell calculates interference contributed to nearby macrocell users and adjusts the power to meet specific target signal-to-interference-plus-noise (SINR) level. Results from simulations show that AIS is able to increase the number of macrocell users achieving target data rates by up to 158% relative to baseline without adaptive control, while resulting in only 12.2% femtocell users receiving rates below the target. AIS achieves improved performance by using location information to calculate and limit the interference power contributed by femtocells to macrocell users, while allowing the network operator to set any desired target rates.