Partial GSM spectrum reuse for femtocells

In this paper the feasibility of femtocells partially reusing GSM spectrum is investigated. Due to the increasing scarcity and cost of spectrum, partial spectrum reuse by secondary networks is being considered to improve spectral efficiency. Additionally, new revenue streams can be extracted from existing resources by utilising partial spectrum reuse. The partial reuse of spectrum depends largely on the ability of the secondary network to mitigate the negative interference impact upon the primary network. This can be achieved by the establishment of acceptable interference criteria. This paper presents a solution to the problem of meeting the interference criteria with regards to frequency allocation and power configuration within the femtocell network. We demonstrate that these solutions can be applied successfully to allow for partial spectrum reuse in the GSM band. Furthermore we present an analysis of both the theoretical performance of femtocells and the resulting impact on the macrocellular network.