Analysis of subchannel reusable probability and capacity for frequency-reused femtocell networks under frequency partitioning strategy

Femtocell is a promising technology to improve network performance with low-power and cost-beneficial small base stations. However, the interference-limited reality in femtocell networks makes interference and resource management the key to achieving the benefits of femtocell networks. In this paper, the following contributions are made step by step: first, on the basis of the interference temperature model (ITM) in cognitive radio (CR) technique and the network architecture of the third generation partnership project (3GPP) long term evolution advanced (LTE-A), the problem model of optimizing the capacity of the femtocell-reused subchannel is established under the frequency partitioning strategy, jointly considering the average interference constraint and the instantaneous interference constraint. Second, utilizing the convex theory, optimal power allocation of the femtocell-reused subchannel is derived. Third, under Rayleigh fading channel, closed-form expressions of the subchannel reusable probability and capacity are derived. At last, numerical results are conducted to confirming our analytical results, which could provide theoretical guidance for frequency resource allocation of femtocell network deployments.