Conference Paper

Hybrid spectrum sharing for coexistence of macrocell and femtocell

DOCOMO Beijing Commun. Labs. Co., Ltd., Beijing, China
DOI: 10.1109/ICCOMTA.2009.5349216 Conference: Communications Technology and Applications, 2009. ICCTA '09. IEEE International Conference on
Source: IEEE Xplore

ABSTRACT This paper investigates flexible spectrum sharing for coexistence of macrocell and femtocell. In such a networking environment, shared spectrum usage and partitioned spectrum usage are two options to be employed between them. After recognizing the pros and cons of these two usages, we propose hybrid spectrum sharing to take advantage of their merits. In our proposal, the femtocells embedded in macrocell are differentiated to inner and outer femtocells, which operate in partitioned spectrum usage and shared spectrum usage, respectively. Performance evaluation are given to justify our proposed method on improving overall spectrum utilization.

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    ABSTRACT: Spectrum sharing usage in two-tier networks miti- gates spectrum scarcity and contributes in satisfying the growing demands for wireless broadband. This paper addresses the Up- link cross-tier interference problem in femtocell system resulting from a spectrum underlay access between a primary system based on a macrocell base station, i.e eNodeB (eNB), with its macrocell user equipments (MUE), and a secondary system based on a femtocell base station, i.e Home eNodeB (HeNB), with its home femtocell user equipments (HUE). We propose a resilient solution to the near-far effect issue by utilizing the interfering macrocell information feedback through infrastructure network at the HeNB for interfered signal recovery of the symbols sent by the HUE. Our proposed method is evaluated by simulation and the results show that the MUE interference can be canceled. Index Terms—Macrocell, femtocell, two-tier networks, MMSE, Interference.


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