Distributed cross-layer resource allocation for statistical QoS provisioning in femtocell networks

In this paper, we study the cross layer design and optimization for delay quality-of-service (QoS) provisioning in spectrum sharing femtocell networks. Our goal is to find the optimal resource allocation policy to maximize the throughput for each femtocell user, addressing the co-channel interference problem in the physical layer and the individual statistical delay-QoS guarantee problem from the upper layers. The statistical delay-QoS requirement is characterized by the QoS exponent. By integrating the concept of effective capacity, the cross-layer optimization problem is formulated as an effective capacity maximization game. With partial dual decomposition, this game is solved through a hierarchical structure. Specifically, we derive the optimal power allocation policy for femtocell users and design a distributed algorithm to obtain the Nash Equilibrium (N.E.). Numerical results show that the proposed policy can efficiently improve the performance of the networks.