Elements of information theory
Elements of information theory
Convex Optimization
An overview of the femtocell concept
Bell Labs Technical Journal - Next-Generation Wireline Access Networks
Uplink capacity and interference avoidance for two-tier femtocell networks
IEEE Transactions on Wireless Communications
Dynamic SLA negotiation using bandwidth broker for femtocell networks
ICUFN'09 Proceedings of the first international conference on Ubiquitous and future networks
Handover between macrocell and femtocell for UMTS based networks
ICACT'09 Proceedings of the 11th international conference on Advanced Communication Technology - Volume 1
OFDMA femtocells: a roadmap on interference avoidance
IEEE Communications Magazine
Efficient handoff algorithm for inbound mobility in hierarchical macro/femto cell networks
IEEE Communications Letters
Spectrum allocation in tiered cellular networks
IEEE Transactions on Communications
Interference mitigation using uplink power control for two-tier femtocell networks
IEEE Transactions on Wireless Communications
Hybrid spectrum usage for overlaying LTE macrocell and femtocell
GLOBECOM'09 Proceedings of the 28th IEEE conference on Global telecommunications
Access control mechanisms for femtocells
IEEE Communications Magazine
IEEE Communications Magazine
Wireless Personal Communications: An International Journal
Realistic Long Term Evolution Performance for Massive HeNB Residential Deployments
Wireless Personal Communications: An International Journal
Wireless Personal Communications: An International Journal
Hi-index | 0.00 |
Orthogonal frequency division multiplex-based femtocell networks in downlink with two-tier interference are considered in this paper. In order to satisfy the quality of service of macrocell users, a capacity maximization problem with the total and the upper power constraints by allocating power to subcarriers for a user in femtocell systems becomes important. In this paper, the optimal power allocation is derived by using the Lagrangian technique. Based on the analysis of the Karush-Kuhn-Tucker conditions, subcarriers can be classified into two sets with different power allocation strategies according to the upper power constraint. One set of subcarriers is allocated with upper power, and the other set of subcarriers is processed by using the waterfilling approach. A direct linear search scheme is presented to achieve the optimal performance by finding the threshold over the channel states of all subcarriers to determine the two sets. In order to reduce the computational load, a reduced complexity scheme is designed for the optimal solution by utilizing the relationship of the allocated power in the two sets of subcarriers. Unlike the schemes in iterative manners, a fast power allocation scheme with a near-optimal performance is also developed. Simulation results reveal that the proposed schemes outperform the existing scheme. The efficacy of the proposed schemes is demonstrated in the simulations.