Fair Resource Allocation With Interference Mitigation and Resource Reuse for LTE/LTE-A Femtocell Networks

Abstract

Joint consideration of interference, resource utilization, fairness and complexity issues is generally lacking in existing resource allocation schemes for Long Term Evolution (LTE)/LTE-Advanced femtocell networks. To tackle this, we employ a hybrid spectrum allocation approach whereby the spectrum is split between the macrocell and its nearby interfering femtocells based on their resource demands, while the distant femtocells share the entire spectrum. A multi-objective problem is formulated for resource allocation between femtocells and is decomposed using a lexicographic optimization approach into two subproblems. A reasonably low-complexity greedy algorithm is proposed to solve these subproblems sequentially. Simulation results show that the proposed scheme achieves substantial throughput and packet loss improvements in low-density femtocell deployment scenarios while performing satisfactorily in high-density femtocell deployment scenarios with substantial complexity and overhead reduction. The proposed scheme also performs nearly as well as the optimal solution obtained by exhaustive search.

Dynamic Resource Management for LTE-Based Hybrid Access Femtocell Systems

“…Furthermore, we assume that a set of PRBPs has been allocated to each femtocell and cochannel interference between femtocells has been mitigated. This assumption can be made valid by using the frequency reuse scheme in [19], which divides the system bandwidth into several frequency bands and allocates these bands to femtocells in such a way that no two adjacent femtocells share the same frequency band; or by using the resource allocation scheme in [20], which allocates resources to femtocells based on the resource demands and interference conditions of the femtocells.…”

“…In LTE-based cellular systems, the second term of the right-hand side of (20) can be estimated based on the CQI feedback from the corresponding UE and the power allocation information of the previous TTI. From the KKT conditions, the following must hold:…”

“…It is obvious from (20) that λ can only be non-zero for any feasible power allocation which satisfies constraint (5c), which implies that…”

Energy efficient resource allocation in two-tier OFDMA networks with QoS guarantees

“…Therefore, by satisfying (9), the transmitting power of FUEs does not disturb the MUEs QoS significantly. In addition, each user requires a data rate which needs to be satisfied by the constraint that is imposed in (8), where C k,u,n is defined in (2).…”

“…In addition, femtocells can boost network performance in terms of high data rate services due to the close proximity of femtocell user equipment (FUEs) to their indoor installed FBS [6], [7]. Although femtocells are beneficial to both operators and users, many technical challenges associated with femtocell deployment arise such as high interference level in the network, radio resource utilization, fairness and complexity [8]. Moreover, energy saving methods attract the attention of researchers for next generation wireless networks such as 4G and 5G [9].…”