Date Added: Nov 2010
The paper is concerned with the study of the cross-tier interference between the femtocell and macrocell layers of a mobile communications network. The main point of interest is consisted by the interference generated by the femtocell to the macrocell user. A mixed indoor-outdoor environment is analyzed and the corresponding problems identified. A solution is proposed consisted in using the existing security alarm system in order to control the transmit power and radiation pattern of the femtocell, performing in this way cross-tier interference mitigation.