| Recently, large amount of emerging indoor users, especially the large amount of indoor data users, together with wall penetration, bring new challenges to the 4G technology and the conventional macro-cellular network model can hardly satisfy indoor user demand with seamless access to high speed applications. As a plug-and-play, self-configured and self-optimized home base station to handle the indoor coverage issues, the femtocell quickly becomes popular among wireless operators, communication equipment manufacturers, as well as the academia society. This paper studies the OFDMA based macro/femtocell tiered network resource management solutions, with main focus on resource allocation and interference suppression:The first part describes the trend of broadband wireless communications networks, and explores the current research progress with femtocells both in domestic and foreign; the second part explores the upper bound of IMT-Advanced based macro/femtocell tiered network capacity using the joint scheduling and optimization strategies targeting at weighted sum capacity maximization, and proposes 3 low-complexity solutions; the third part studies effective radio resource management approaches with objective to approximate the capacity boundary and to address interference issues of the macro/femtocell tiered networks. Finally, based on the cutting-edge grasp, it is forecast that in the future, more meaningful exploration would be carried on the femtocell with aspects like energy saving, multi-network collaboration, and intelligent networking. |
