A Novel Proportionally Fair Spectrum Allocation in Two Tiered Cellular Networks

Heterogeneity in cellular networks leads to a complex scenario wherein several tiers co-exist. For closed access scenario in such a heterogeneous network, the inter-tier interference has an impact on the overall network throughput. The impact becomes severe with increasing base station density in the interfering tiers. Here, we present a method of orthogonal spectrum allocation for two tiered cellular networks such that each tier gets improvement in mean throughput over the co-channel deployment. We have formulated the problem as a novel proportionally fair spectrum allocation and prove that a unique Nash Bargaining Solution exists. Necessary conditions for the existence of optimal bandwidth partioning is also derived.