Network Synchronization Among Femtocells
To successfully deploy femtocells overlaying the Macrocell as a two-tier that had been shown greatly benefiting communications quality in various manners, it requires to mitigate cross-tier interference between the Macrocell and femtocells, as well as intra-tier interference among femtocells. For this purpose, solutions for interference mitigation have been proposed for femtocells in literatures. However, an essential assumption of these solutions is that all femtocells and the Macrocell shall be synchronized. Such a (network) synchronization of the Macrocells and user deployed femtocells create diverse challenges from conventional synchronization among Macrocells.