Content-aware spectrum and power allocation for video multicast in two-tier femtocell networks

Allocation of wireless spectrum and transmission power for video multicast in a two-tier femtocell network is a challenging problem because of network dynamics, variable video bit-rates, and heterogeneous clients who watch various videos as well as are at different locations. Since femtocells provide coverage using typical cellular system air interface, the co-channel interference may significantly limit the capacity improvement in this two-tier network. Hence, the focus of this work is to figure out an effective way to cope with the interference issue by allocating system resources (sub-channels and transmission power) efficiently for video multicast users. Prior works apply channel assignment or power control schemes by considering only characteristics of underlying wireless resources. We, however, note that for a video multicast user, the user perceived video quality is associated with not only the wireless channel condition but also the video content. Motivated by this observation, we propose a content-aware spectrum and power allocation scheme (CSPA), which considers both characteristics of underlying wireless resources and video contents. Through simulation, results show that CSPA is able to enhance the users´ watching video quality than other existing schemes; and the gap between CSPA and other schemes becomes larger when all users´ contents become more diverse.