Spectrum Allocation in Two-Tier Networks

Abstract-- Two-tier networks, comprising a conventional cellular network overlaid with shorter range hotspots (e.g. femtocells, distributed antennas, or wired relays), offer an economically viable way to improve cellular system capacity. The capacitylimiting factor in such networks is interference. The cross-tier interference between macrocells and femtocells can suffocate the capacity due to the near-far problem, so in practice hotspots should use a different frequency channel than the potentially nearby high-power macrocell users. Centralized or coordinated frequency planning, which is difficult and inefficient even in conventional cellular networks, is all but impossible in a twotier network. This paper proposes and analyzes an optimum decentralized spectrum allocation policy for two-tier networks that employ frequency division multiple access (including OFDMA). The proposed allocation is optimal in terms of Area Spectral Efficiency (ASE), and is subjected to a sensible Quality of S...

• Type: Journal
• Year: 2008
• Where: CORR
• Authors: Vikram Chandrasekhar, Jeffrey G. Andrews
• Keywords: Conventional Cellular Networks, CORR 2008, Education, Femtocells, Two-tier Networks